HomeMy WebLinkAboutOrd 2675 - EXHIBIT B: 2021 King County Stormwater Pollution Prevention Manual (Dated July 2021)
Stormwater Pollution
Prevention Manual:
Best Management Practices for
Commercial, Multifamily and
Residential Properties
July 2021
Department of Natural Resources and Parks
Water and Land Resources Division
Stormwater Services Section
King Street Center, KCS-NR-5600
201 South Jackson Street, Suite 5600
Seattle, WA 98104
206-477-4800 TTY Relay: 711
www.kingcounty.gov/stormwater
www.kingcounty.gov/sppm
Foreword
The King County (SPPM) was developed to comply
with requirements of the Federal Clean Water Act–National Pollutant Discharge
Elimination System (NPDES) Program and the State Puget Sound Water Quality
Management Plan–Stormwater Program. The intent of these programs is to maintain and
improve the quality and beneficial uses of our water resources. The widespread
implementation of best management practices (BMPs) is regarded as one of the best
solutions to achieving this goal. This manual provides detailed information for businesses,
residents, managers, and owners of property in unincorporated King County, and describes
the actions we are all required to take to reduce the contamination of stormwater, surface
water (e.g., streams and lakes), and groundwater.
Note: This manual replaces the King County , Best
Management Practices for Businesses, dated April 2016.
Acknowledgements
f:
Bob Bernhard, Source Control Program Manager (2021-present)
Cynthia Hickey, Source Control Program Manager(2009-2021)
Alison Schweitzer, Program/Project Manager
The authors would like to thank David Batts, Cameron Chapman, Jeanne Dorn, Marilyn
Guthrie, Abby Hawley, Lou Leet, Edward McFarlin, Doug Navetski and Mark Wilgus for
their valuable input.
Clarification of Manuals
The ion (www.kingcounty.gov/sppm) presents
pollution prevention practices for all property owners in unincorporated King County. Use
the (www.kingcounty.gov/swdm)for
construction projects that require King County permits and have stormwater quantity and
quality control requirements. Redevelopment or property improvements on existing sites
may require structural BMPs. Structural BMPs are found in this manual as well as the
KCSWDM.
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Table of Contents
1.0Overview....................................................................................................................................................1
1.1About This Manual............................................................................................................................. 1
1.2Best Management Practices (BMPs) ........................................................................................... 1
1.3Exemptions ........................................................................................................................................... 2
1.4Step by Step Approach ..................................................................................................................... 2
1.5Activities That May Result in Structural Improvements .................................................... 4
1.6Other Agency Requirements .......................................................................................................... 6
1.7Your Stormwater Drainage System............................................................................................ 7
2.0Stormwater problems ........................................................................................................................... 9
2.1Stormwater Runoff ............................................................................................................................ 9
2.2Storm Drains That Lead to Lakes and Streams ...................................................................... 9
2.3Polluting is Against the Law........................................................................................................... 9
2.4Ways You May Be Polluting ........................................................................................................... 9
2.5Pollutants ............................................................................................................................................10
2.5.1Oils, Greases, and Fuels............................................................................................................10
2.5.2Metals .............................................................................................................................................10
2.5.3Sediments ......................................................................................................................................10
2.5.4Oxygen–Demanding Substances ..........................................................................................11
2.5.5Nutrients........................................................................................................................................11
2.5.6Toxic Organic Compounds ......................................................................................................11
2.5.7Fecal Bacteria..............................................................................................................................12
2.5.8pH.....................................................................................................................................................12
3.0Commercial and Multifamily BMPs ...............................................................................................13
3.1Pollution Prevention Practices ...................................................................................................13
3.2BMP Activity Sheets ........................................................................................................................16
A-1:Required BMPs for All Properties with Commercial Activities .................. 17
A-2:Outdoor Storage of Liquid Materials in Stationary Tanks ............................ 19
A-3:Storage of Liquid Materials in Portable Containers........................................ 21
A-4:Outdoor Storage of Soil, Sand, and Other Erodible Materials ..................... 23
A-5:Storage and Use of Pesticides and Fertilizers .................................................... 25
A-6:Storage of Contaminated Soils ................................................................................. 31
A-7:Food and Beverage Manufacturing and Storage .............................................. 32
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A-8:Storage of Solid Waste and Food Wastes (Including Cooking Grease) ....35
A-9:Storage of Scrap and Recycling Materials (Including Auto Recycling
Facilities) ......................................................................................................................... 37
A-10:Treatment, Storage or Disposal of Dangerous Wastes .................................. 39
A-11:Cleaning or Washing of Tools and Equipment .................................................. 40
A-12:Cleaning of Washing of Food Service Areas and Equipment ....................... 42
A-13:Vehicle Washing and Steam Cleaning...................................................................43
A-14:Interior Washing Operations (Including Mobile Contractors) ................... 45
A-15:Washing of Buildings, Rooftops, and Other Large Surfaces ......................... 46
A-16:Truck or Rail Loading and Unloading of Liquid or Solid Material ............. 48
A-17:Stationary Fueling Operations ................................................................................. 49
A-18:Vehicle and Equipment Repair and Maintenance ............................................ 53
A-19:Concrete and Asphalt Production and Recycling............................................. 55
A-20:Concrete and Asphalt Application.......................................................................... 57
A-21:Manufacturing and Post-Processing of Metal Products ................................ 59
A-22:Painting, Finishing, and Coating of Vehicles, Products and Equipment..61
A-23:Wood Treatment and Preserving........................................................................... 63
A-24:Commercial Composting............................................................................................ 64
A-25:Chemical Applications – Other Than Landscaping .......................................... 66
A-26:Landscaping Activities, Vegetation Management, and Irrigation .............. 68
A-27:Clearing and Grading of Land for Small Construction Projects .................. 73
A-28:Demolition of Buildings ............................................................................................. 74
A-29:Building Repair, Remodeling and Construction............................................... 76
A-30:Marine Activities ........................................................................................................... 78
A-31:Parking Lots, Driveways and Outside Storage Areas...................................... 85
A-32:Sidewalk Maintenance ................................................................................................ 87
A-33:Swimming Pool and Spa Cleaning and Maintenance ...................................... 88
A-34:Animal Waste ................................................................................................................. 90
A-35:Keeping Livestock in Stables, Pens, Pastures or Fields.................................. 92
A-36:Logging and Log Yards ............................................................................................... 95
A-37:Mining and Quarrying of Sand, Gravel, and Other Materials ....................... 96
A-38:Well, Utility, Directional and Geotechnical Drilling ......................................... 97
A-39:Roof Vents and Fugitive Emissions ....................................................................... 99
A-40:Street Deicing Operations ....................................................................................... 101
A-41:Wheel Wash and Tire Bath Track Out Control ................................................ 102
A-42:Potable Water Line Flushing, Water Tank Maintenance and Hydrant
Testing............................................................................................................................ 103
A-44:Dust Control for Commercial Operations.......................................................... 105
A-45:Maintenance of Public and Private Utility Corridors and Facilities ........ 107
A-46:Color Events.................................................................................................................. 109
A-47:Older Stationary Fueling Operations .................................................................. 112
A-48:Mobile Fueling of Vehicles and Heavy Equipment ........................................ 116
A-49:Nurseries and Greenhouses ................................................................................... 119
4.0Residential (Non-Commercial) BMPs ........................................................................................ 122
R-1:Residential Automobile and Boat Washing...................................................... 123
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R-2:Residential Storage of Solid Waste and Food Wastes (Garbage)............. 125
R-3:Residential Vehicle Repair and Maintenance.................................................. 126
R-4:Residential Hazardous Waste Use, Storage and Disposal ........................... 127
R-5:Residential Gardening, Lawn Care, Irrigation and Fertilizer
Application….. .............................................................................................................. 128
R-6:ResidentialHome Maintenance and Repair ..................................................... 130
R-7:Residential Swimming Pool and Hot Tub Maintenance..............................132
R-8:Residential Animal Waste ....................................................................................... 134
R-9:Residential Dock Washing....................................................................................... 137
5.0Information Sheets ............................................................................................................................ 140
Catch Basin Inserts ....................................................................................................................... 141
Containment .................................................................................................................................... 145
Controlling and Collecting Contaminated Runoff ............................................................. 148
Covering. ........................................................................................................................................... 151
Disposal............................................................................................................................................. 153
Drainage Maintenance Contractors....................................................................................... 157
Oil/Water Separator .................................................................................................................... 162
Spill Response and Cleanup Plan............................................................................................ 164
Water Quality Treatment BMPs.............................................................................................. 170
6.0Technical Assistance ......................................................................................................................... 173
6.1General BMP Selection................................................................................................................ 173
6.2Sanitary Sewer and Septic Systems Resources .................................................................174
6.3Waste Management and Recycling......................................................................................... 174
6.4Land Use, Fire Code, and Building Code Requirements ................................................. 177
6.5Erosion Control Practices .......................................................................................................... 177
6.6Air Quality........................................................................................................................................ 178
6.7Environmental Organizations .................................................................................................. 179
6.8Quick Phone References.............................................................................................................180
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1.0OVERVIEW
1.1About This Manual
King County’s water resources – its streams, lakes, wetlands, groundwater, and Puget
Sound – play an important role in the quality of life we enjoy. They provide us with
recreation and drinking water, support tourism, salmon and multiple other fish species,
and are used extensively in industry. These waters, however, are vulnerable to pollution
from a wide variety of human activities.
Many of our water pollution problems are due in large part to pollutants washed off of land
by storms. The quality of “stormwater” from residential properties, public facilities,
commercial and industrial businesses, and agricultural lands is an increasing concern
nationwide. The amount of pollution from any one place may not be significant by itself, but
cumulative effects to water quality can be significant.
The federal Clean Water Act mandates that cities and counties control the quality of
stormwater runoff through implementation of pollution prevention measures. To meet the
requirements of the Clean Water Act and to sustain our quality of life, the King County
Council passed King County Water Quality Code (KCC 9.12) in November 1992.
This manual applies to all activities in unincorporated King County that have the potential
to contribute pollutants to stormwater runoff or to receiving waters directly. Stormwater
runoff may seep into the ground, drain to a storm drain or a drainage ditch, or flow over the
ground. Regardless of the way runoff leaves the site, it can end up in a stream, river, lake,
wetland, groundwater, or Puget Sound.
King County Water Quality Code (KCC 9.12) requires the use of best management practices
(BMPs) described in this manual. The manual includes:
Stormwater BMPs for commercial, industrial, public, and multifamily residential
activities (Chapter 3).
Stormwater BMPs for single family residential properties (Chapter 4).
Information on how to implement many stormwater BMPs (Chapter 5).
Additional resources (Chapter 6)
1.2Best Management Practices (BMPs)
The methods of protecting the quality of stormwater, surface water (e.g., streams and
lakes) and groundwater, are called best management practices (BMPs). BMPs encompass a
variety of managerial, operational, and structural measures that will reduce the amount of
contaminants in stormwater and improve the quality of our water resources.
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BMPs are separated into two broad categories: source control and treatment. Sourc
prevent contaminants from entering water bodies or stormwater runoff.
Some source control BMPs are operational, such as checking regularly for leaks and drips
from equipment or vehicles, covering materials that have the potential to add pollutants to
surface water, and educating employees about site clean–up procedures. Other source
control BMPs are structural, including roofs, berms, and fueling pads.
are activities that treat stormwater to remove pollutants although no
treatment BMP can remove 100 percent of the contaminants.
It is more efficient, effective, and economical to prevent the contamination ofstormwater
than to treat it.
1.3Exemptions
You are exempt from implementing equivalent BMPs in this manual if you:
Have obtained and are complying with a permit under the National Pollutant
Discharge Elimination System (NPDES) Stormwater Permit Program.
Implement and maintain a farm management plan developed by the King
Conservation District (KCD) and approved by King County Department of Natural
Resources and Parks.
Implement BMPs in compliance with KCC 21A.30, which addresses animal and
livestock keeping practices.
Engage in forest practices, with the exception of Class IV general forest practices.
These exemptions are only from the requirements of this manual. If you are exempted for
one or more of the reasons listed above, King County assumes that you are implementing
the appropriate BMPs. If you have not implemented BMPs, or they are not effectively
addressing the discharge of contaminants, then you will be required to comply with this
manual. The following is a step–by–step approach to BMP compliance.
1.4Step by Step Approach
1. - If you are not exempt due to an above listed reason, then
you must comply with the BMPs in this manual.
2. -Determine which activities in this manual are
applicable to your property using the BMP Identification Worksheet. Review the
applicable BMP activity sheets which can be found in Chapter 3 of this manual and
on our website at www.kingcounty.gov/sppm.
You will need to be familiar with the stormwater drainage system on your site.
3. - You can have a free on–site consultation with a staff member
from King County Stormwater Services who will walk through your site, discuss
conditions and necessary BMPs, and provide assistance with implementation. To
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request an on–site consultation, call King County Stormwater Services at 206–477–
4811.
4. -
Discharges from internal floor drains, appliances, industrial processes, and sinks
and toilets that are connected to the nearby stormwater drainage system can cause
significant stormwater pollution. These discharges must go to the sanitary sewer
system, a holding tank, an on–site process water treatment system or a septic
system.
For information on how to check for illicit connections refer to BMP activity sheet A-
1: Required BMPs for All Properties with Commercial Activities. You can also get
help from your local sewer utility. If you find out that your internal drains are
improperly connected to the stormwater drainage system, they will need to be
removed, permanently plugged, or connected to the sanitary sewer, septic system,
on–site treatment system under certain conditions, or a holding tank.
–
non–
–
5.- Look at the property as a whole to
determine how the BMPs you implement will work together. There may be
acceptable BMPs that are not listed in the manual. Be creative in assessing your own
needs and the constraints that you may face on your property.
6.- First, implement the BMPs
that do not require extensive construction. Examples include having spill control
and cleanup materials on site, using drip pans or drop cloths when conducting day
to day activities, and sweeping instead of hosing down an area to a storm drain.
7.Necessary - Second, implement the
structural source control BMPs that may require a building permit or require larger
capital expenditures. Examples include constructing a building to enclose a work
activity that is currently in the open, or building a containment area.
8. - If a treatment BMP is determined to be necessary
for your site, you must have an acceptable design prepared and approved by King
County Water and Land Resources Division (WLRD). You may be required to use the
(KCSWDM) when designing and receiving
approval of treatment BMPs. Once the design has been approved by WLRD and a
permit issued (if necessary) from the King County Department of Local Services,
Permitting Division (Permitting), construction may begin.
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9. -Keep copies of the activity sheets and other documentation on
implementing BMPs. Records may be used to illustrate compliance with this manual.
10. - Business owners and property managers must ensure
employees are maintaining all applicable BMPs in Chapter 3. Employee education
should be a continuous process for effective BMP implementation. Single family
residential properties are also required to maintain all applicable BMPs in Chapter
4.
1.5Activities That May Result in Structural
Improvements
There are a number of activities that may require structuresand/or specific drainage
configurations in order to protect stormwater and maintain compliance with King County
Water Quality Code 9.12. Roof structures, wheel washes, cement pads, shutoff valves,
containment berms and indoor mop sinks are all examples of things that need to be in place
prior to commencing the activity. These may require building permits and other approvals
prior to construction. For information contact Permitting at 206-296-6600 or
DPERWebInquiries@kingcounty.gov.
Below are some highlighted activities and BMP activity sheets that provide more detail:
Structural improvements: paved composting and storage pads, leachate collection system,
lined collection ponds, contaminated stormwater collection and treatment, and wheel wash
system
BMP activity sheet A-24: Commercial Composting
Structural improvements: roofed enclosures, containment, wastewater collection, storage,
and disposal system
BMP activity sheet A-7: Food and Beverage Manufacturing and Storage
Structural improvements: Portland cement pads, roofs, spill control devices, trench drains,
and oil/water separators
BMP activity sheet A-17: Stationary Fueling Operations
BMP activity sheet A-47: Older Stationary Fueling Operations
Structural improvements: berms, covering and erosion control measures
BMP activity sheet A-4: Outdoor Storage of Soil, Sand and Other Erodible Materials
BMP activity sheet A-49: Nurseries and Greenhouses
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Structural improvements: wash racks connected to sanitary sewer or separate infiltration
area, and manure containment areas
BMP activity sheet A- 35: Keeping Livestock in Stables, Pens, Pastures or Fields
Structural improvements: wheel wash system and track–out control, and catch basin
inserts
BMP activity sheet A-41: Wheel Wash and Tire Bath Track Out Control
Structural improvements: wheel wash system and track–out control, berms, containment
areas, covering, paving, catch basin inserts, and treatment systems
BMP activity sheet A-41: Wheel Wash and Tire Bath Track Out Control
Structural improvements: roofs or other covering, and stormwater collection and
treatment system
BMP activity sheet A-21: Manufacturing and Post–Processing of Metal Products
Structural improvements: permitted and enclosed paint booths
BMP activity sheet A-22: Painting, Finishing and Coating of Vehicles, Products, and
Equipment
Structural improvements: indoor sinks for mat and rack washing, and mop and wastewater
disposal
BMP activity sheet A-8: Storage of Solid and Food Wastes (Including Cooking
Grease)
BMP activity sheet A-12: Cleaning or Washing of Food Service Areas and Equipment
Structural improvements: secondary containment, roofed structures, and spill control
devices
BMP activity sheet A-2: Storage of Liquid Materials in Stationary Tanks
BMP activity sheet A-3: Storage of Any Liquid Materials in Portable Containers
Structural improvements: road stabilization
BMP activity sheet A-45: Maintenance of Public and Private Utility Corridors and
Facilities
5
Structural improvements: dedicated wash pads, sewer connection, holding tanks and catch
basin inserts
BMP activity sheet A-11: Cleaning or Washing of Tools and Equipment
BMPactivity sheet A-13: Vehicle Washing and Steam Cleaning
Structural improvements: paved, contained, and covered storage and processing areas
BMPactivity sheet A-23: Wood Treatment and Preserving
1.6Other Agency Requirements
Please note that other federal, state, and local agencies enforce regulations that may relate
to your implementation of BMPs. Consult the following entities for guidance on the listed
activities:
Drainage requirements, and construction BMPs for erosion and sediment control for
new development and redevelopment
Land use regulations protecting environmentally sensitive areas and public health
and safety
Storage and handling of flammable, combustible, and hazardous materials
nce)
Raising and keeping of livestock
-
Acceptance of process water or contaminated stormwater to sanitary sewers
–Hazardous
Acceptance of household hazardous waste from residents and qualifying small
quantity generators
–
Solid waste
6
Septic systems (on–site septic systems)
Structural pesticide applicators
National Pollutant Discharge Elimination System (NPDES) permits
Discharge of process wastewater to surface water
Underground storage tanks
Spill prevention and control plans
Dangerous waste generators
Groundwater quality protection
Oil spill prevention and cleanup plans (with U.S. Environmental Protection Agency)
Pesticide applications
Nutrient management plans
Fugitive dust
Outside painting
Spray booths
Transfer of petroleum products on Puget Sound
1.7Your Stormwater Drainage System
If you have a set of plans/blueprints of your site and the associated stormwater drainage
system, familiarize yourself and your employees with drainagepatterns and drainage
structure location. If you do NOT have a set of plans for the property, prepare a rough
sketch to familiarize yourself and your employees with your on–site stormwater drainage
system to aid in the implementation of BMPs. See the following page for an example. The
sketch should include the following:
Drainage structures—such as storm drains/catch basins, pipes, ditches, ponds, and
vaults
Buildings
Storage structures/sheds
Storage areas
Places/points where stormwater leaves your site
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Example of a stormwater drainage system sketch with additional site elements (e.g.,
buildings, storage areas, stormwater drainage flow and exits)
If you have any questions call King County Stormwater Services at 206–477–4811.
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2.0STORMWATER PROBLEMS
2.1Stormwater Runoff
In vegetated areas (e.g., forests, fields, and wetlands) rainwater seeps slowly into the
ground. However, when rain falls on paved and other hard, impervious surfaces it runs off
quickly and is conveyed by pipes and ditches directly to water bodies (e.g., lakes, wetlands,
and streams). This water, including snowmelt, that flows across the land is called
stormwater runoff. Stormwater runoff collects pollutants when it hits the ground and
carries it to stormwater drainage systems, surface waters and ultimately to Puget Sound.
For example, stormwater runoff from parking lots picks up oil and grease dripped from
cars, asbestos from worn brake linings and zinc from tires. Pesticides, herbicides, and
fertilizers are washed off from landscaped areas, and soils are washed away from
construction sites. Any substance found on the ground can contaminate stormwater runoff.
2.2Storm Drains That Lead to Lakes and Streams
Stormwater drainage systems are designed to decrease the chance of flooding in developed
areas. The stormwater drainage system collects stormwater runoff from catch basins
(storm drains), roof downspouts, footing drains, and other inlets. The stormwater is then
conveyed to the nearest surface water—such as a wetland, lake, stream or to Puget Sound.
In urban areas, the stormwater drainage system consists primarily of drains and
underground pipes. In rural areas, the stormwater drainage system may be in the form of
ditches. Drainage systems are meant to carry only unpolluted stormwater to the nearest
natural body of water.
In areas that are served by sanitary sewer, interior drains—including toilets, floor drains
and process water—lead to the sanitary sewer system and end up at a wastewater
treatment plant where the wastewater is treated before being discharged into Puget Sound.
In areas that do not have sanitary sewer the interior drains go to an on-site sewage
treatment system, known as an on–site septic system (OSS). The wastewater is treated
naturally and infiltrates on site.
2.3Polluting is Against the Law
The Washington State Water Pollution Control Law (RCW 90.48) and the King County
Water Quality Code (KCC 9.12) prohibit the discharge of pollutants to stormwater drainage
systems, surface waters, and groundwater. Pollution can cause harmful algal blooms,
lesions and tumors in fish and other animals, destruction of fish spawning areas, damage
habitat for plants and animals, and impairment of recreational activities.
2.4Ways You May Be Polluting
Many people know that it is illegal to dump toxic chemicals or other material directly down
a storm drain but some of the more common pollution generating activities include:
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Washing tools and equipment outside
Hosing down your work area, driveway, or sidewalk
Blowing leaf litter and sediment into the street
Spilling oil or grease on pavement without cleaning it up
Not repairing leaking vehicles
Digging without taking steps to prevent erosion
Washing vehicles even with “environmentally safe” or “green” cleaners
2.5Pollutants
Any substance that can render water harmful to people, fish, or wildlife or impair
recreation or other beneficial uses of water is considered a pollutant. The broad categories
of pollutants and their effects on fish and wildlife are described below.
2.5.1Oils, Greases, and Fuels
Oils and greases have many common sources: driveways, streets, highways, parking lots,
food waste storage areas, heavy equipment and machinery storage areas, and places where
pesticides have been applied. The familiar sight of a rainbow–colored puddle or stream of
water in parking lots, driveways, and street gutters is a reminder of the presence of oils and
greases in stormwater runoff. Oils and greases can be petroleum–based (motor oil) or
food–related (cooking oils). Oil and grease are known to be toxic to aquatic organisms even
at relatively low concentrations. They can coat fish gills, prevent oxygen from entering the
water, and clog drainage facilities.
2.5.2Metals
Many metals, including lead, copper, zinc, and cadmium, are commonly found in urban
runoff. Metals can contaminate surface water and groundwater, and can accumulate in
sediments causing health problems for fish and animals that eat from the bottom of lakes,
streams, and Puget Sound. This in turn harms the people who consume the fish caught in
contaminated areas. Industrial areas, scrap yards, paints, pesticides, and fallout from
automobile emissions are typical sources of metals in runoff.
2.5.3Sediments
Sediment, often originating as soil particles, sand, and clay, is the most common pollutant
in stormwater runoff by volume and weight. Excess sediment turns stream and lake water
cloudy, making them less suitable for recreation, fish life, and plant growth. Sediment is of
particular concern in fish–bearing streams where it can smother fish eggs, destroy habitat
for insects (a food source for fish), and cover prime spawning areas. Sediment can also clog
storm drains, leading to increased private and public maintenance costs and flooding
problems.
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Sediment is also of concern because many other pollutants—including polychlorinated
biphenyls (PCBs), oils, metals, bacteria, and nutrients—tend to attach to soil particles.
Construction sites and exposed earth are generally the greatest contributors of sediment in
surface waters. Other sources include erosion from agricultural lands, pressure washing
and sandblasting operations, loose dirt and debris tracked out to roads by equipment and
vehicles, and dirt and grit from parking lots, driveways, and sidewalks.
2.5.4Oxygen–Demanding Substances
Plant debris, yard waste, food waste, compost, sawdust, and some chemical wastes fall into
a category of water pollutants known as oxygen–demanding substances. Such substances
use dissolved oxygen in water when they decay or chemically react. If dissolved oxygen
levels in water become too low, aquatic animals become stressed or die. Salmon and trout
are particularly at risk because they need high dissolved oxygen levels to live.
Animal wastes, food wastes, yard waste and other miscellaneous organic matter carried by
stormwater runoff into surface water can lead to reduced oxygen levels. Slow–moving
waters are particularly susceptible to oxygen depletion because there is little aeration of
the water by turbulence. Therefore, oxygen that is depleted in slow–moving waters is not
replaced.
2.5.5Nutrients
Plants need nutrients (e.g., phosphorus and nitrogen) to grow but high levels can be
harmful to water quality. Excess nutrient levels can over–stimulate the growth of algae and
other aquatic plants, resulting in unpleasant odors, unsightly surface scum, and lowered
dissolved oxygen levels from plant decay. Nutrients are most likely to pose a problem in
slow moving water such as lakes or sluggish streams.
Some forms of algae are toxic to fish and other aquatic organisms and may even cause
death in animals that drink affected water. Algae can also cause taste and odor problems in
drinking water, foul–smelling odor in ponds and lakes, and problems with clogged water
intakes, drains, and pipes. Forms of nitrogen (ammonium), in combination with pH and
temperature variations, can cause water quality problems and be toxic to fish.
Fertilizers, animal wastes, failing septic systems, detergents, road deicing chemicals,
automobile emissions, eroded soils, and organic matter such as yard waste are all
contributors to excessive nutrient levels in urban, rural, and agricultural stormwater
runoff.
2.5.6Toxic Organic Compounds
Excessive application of toxic organic compounds—such as insecticides, herbicides,
fungicides, and rodenticides (all referred to as pesticides)—or the application of any of
these shortly before or during rainfall can result in the pesticide being carried from
agricultural lands, construction sites, parks, golf courses, and residential lawns and gardens
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to receiving waters. Many pesticide compounds are extremely toxic to aquatic organisms
and can cause fish kills.
Other toxic organic compounds—such as phenols, glycol ethers, esters, nitrosamines, and
other nitrogen compounds—also affect receiving waters. Common sources of these
compounds include wood preservatives, antifreeze, dry cleaning chemicals, cleansers, and
a variety of other chemical products. Like pesticides, these toxic organic compounds can be
lethal to aquatic organisms.
2.5.7Fecal Bacteria
Fecal bacteria in water may indicate the presence of pathogenic (disease–causing) bacteria
and viruses. Pet and other animal wastes, failing septic systems, livestock waste, and
fertilizers can all contribute fecal coliform bacteria. Bacterial contamination has led to
closures of numerous shellfish harvesting areas and swimming beaches in the Puget Sound
region.
2.5.8pH
The pH value of water is an indication of its relative acidity. The pH value can range from 0
to 14, with 6 to 8 being desirable for most bodies of water. A pH level outside this range
will adversely affect plant and animal life. Waters with very high (basic) or very low
(acidic) pH are corrosive to metal surfaces. There are several sources that can contribute to
change of pH in stormwater runoff, including industrial processes that discharge acidic
wastewater, solutions used in metal plating operations, acidic chemicals used in printing
and graphic art businesses, cement used in concrete products and concrete pavement, and
chemical cleaners used in homes and businesses.
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3.0COMMERCIAL AND MULTIFAMILY
BMPS
3.1Pollution Prevention Practices
The eight pollution prevention practices listed below are measures that should be
considered at all times for improving pollution control. They are not required but should be
incorporated in your BMP implementation plan. Application of these pollution prevention
practices may reduce or eliminate the need for more complicated or costly BMPs.
1.Locate activities as far as possible from surface drainage paths
2.Avoid the activity or reduce its occurrence
3.Use less material
4.Use the least toxic materials available
5.Create and/or maintain vegetated areas near activity locations
6.Recycle as much as possible
7.Educate others about stormwater pollution prevention
8.Implement treatment BMPs
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Complete a BMP Identification Worksheet to identify activities you conduct.Interpret the
categories broadly. Activity sheet numbers correspondto BMP Activity Sheets in Chapter 3.
WORKSHEET
IndoorsOutdoors
Storage
A-1 Required BMPs for All Properties with Commercial Activities
A-2 Outdoor Storage of Liquid Materials in Stationary Tanks
A-3 Storage of Liquid Materials in Portable Containers
A-4 Outdoor Storage of Soil, Sand and Other Erodible Materials
A-5 Storage and Use of Pesticides and Fertilizers
A-6 Storage of Contaminated Soils
A-7 Food and Beverage Manufacturing and Storage
A-8 Storage of Solid Wastes and Food Wastes (Including Cooking
Grease)
A-9 Storage of Scrap and Recycling Materials (Including Auto
Recycling Facilities)
A-10 Treatment, Storage or Disposal of Dangerous Wastes
A-31 Parking Lots, Driveways and Outside Storage Areas
Washing
A-11Cleaning or Washing of Tools and Equipment
A-12 Cleaning or Washing of Food Service Areas and Equipment
A-13 Vehicle Washing and Steam Cleaning
A-14 Interior Washing Operations (Including Mobile Contractors)
A-15 Washing of Buildings, Rooftops and Other Large Objects
A-32 Sidewalk Maintenance
A-41 Wheel Wash and Tire Bath Track Out Control
A-16 Truck or Rail Loading and Unloading of Liquid or Solid Materials
A-17 Stationary Fueling Operations
A-18 Vehicle and Equipment Repair and Maintenance
14
A-47 Older Stationary Fueling Operations
A-48 Mobile Fueling of Vehicles and Heavy Equipment
A-19 Concrete and Asphalt Production and Recycling
A-20 Concrete and Asphalt Application
A-21 Manufacturing and Post–Processing of Metal Products
A-22 Painting, Finishing and Coating of Vehicles, Products, and
Equipment
A-23 Wood Treatment and Preserving
A-24 Commercial Composting
A-25 Chemical Applications–Other Than Landscaping
A-37 Mining and Quarrying of Sand, Gravel, and Other Materials
A-39 Roof Vents and Fugitive Emissions
A-44 Dust Control for Commercial Operations
Landscaping
A-26 Landscaping Activities, Vegetation Management, and Irrigation
Construction
A-27 Clearing and Grading of Land for Small Construction Projects
A-28 Demolition of Buildings
A-29 Building Repair, Remodeling and Construction
A-30 Marine Activities
Other
A-33 Swimming Pool and Spa Cleaning and Maintenance
A-34 Animal Waste
A-35 Keeping Livestock in Stables, Pens, Pastures or Fields
A-36 Logging and Log Yards
A-38 Well, Utility, Directional and Geotechnical Drilling
A-40 Street Deicing Operations
Potable Water Line Flushing, Water Tank Maintenance and
A-42
Hydrant Flushing
A-45 Maintenance of Public and Private Utility Corridors and Facilities
A-46 Color Events
A-49 Nurseries and Greenhouses
15
3.2BMP Activity Sheets
The BMPs in this chapter are required for commercial, industrial, agricultural, public, and
multifamily residential activities conducted in unincorporated King County.
King County’s goal is to reduce pollution through education and prevention efforts,
emphasizing source control BMPs before treatment. If the implemented BMPs are not
enough to prevent contamination of stormwater, additional measures will be required.
Every property in the county has unique characteristics and drainage systems. The BMPs
used on each property depend on the type of stormwater drainage system, slope, ground
cover and pollution generating activities occurring on site. The activity sheets offer
flexibility in BMP selection and recognize the wide variety of site conditions that may be
encountered. For manufacturing and commercial activities not addressed in these activity
sheets refer to the Washington State Department of Ecology
, Volume IV (https://ecology.wa.gov/Regulations-
Permits/Guidance-technical-assistance/Stormwater-permittee-guidance-
resources/Stormwater-manuals)for the required Operational and Structural Source
Control BMPs.
16
A-1:Required BMPs for All Properties with Commercial
Activities
The following best management practices (BMPs) are required for all commercial,
industrial, agricultural, public, and residential properties with commercial activities in
unincorporated King County.
In addition to implementing required BMPs listed herein, property owners must maintain
drainage facilities to meet King County Standards, as required by King County Code
9.04.120.
BMPs are required by King County Water Quality Code 9.12. If the BMPs included here are
not enough to prevent contamination of stormwater, you will be required to take additional
measures.
Required BMPs
Evaluate the condition of the catch basin by checking the amount of sediment in the
bottom of the catch basin (sump). Catch basins must be cleaned out when the solids,
trash and debris in the sump reaches one–half of the depth between the bottom of
the sump and the bottom of the lowest inflow or outflow pipe connected to the catch
basin or is at least 6 inches below thispoint.
Clean and maintain catch basins annually. Sites with activities generating sediments
and other debris will have to inspect and clean out their catch basins more often.
Frequent sweeping of paved parking and storage areas will save time and money in
maintaining the stormwater drainage system.
Hire a professional drainage contractor to inspect and maintain your stormwater
drainage system or clean the system yourself. If there is sediment or other debris in
the drainage pipes, then a professional contractor must be hired to flush or jet out
the pipes. Confined space entry should only be conducted by individuals trained to
do so. For information on confined spaces refer to www.osha.gov/confined-spaces
Soak up small amounts of floating oil with absorbent pads. The pads and
nonhazardous sediments can be bagged up and disposed of as solid waste. Up to
one cubic yard of nonhazardous solid material may be disposed of as solid waste in
your regular garbage. For additional information please call King County Solid
Waste Division at 206-477-4466. If you exceed this threshold hire a professional
drainage contractor. For information on how to use absorbent pads please watch
Seattle Public Utility’s video Your
(https://www.youtube.com/watch?v=NeH98Rx7dOE).
All of the solids and stagnant water collected from catch basin sumps must be
disposed of properly. None of the sump contents can be flushed into the catch basin
outflow pipe. Contractors who perform catch basin clean-out services are required
to follow appropriate disposal requirements.
17
Other components of the stormwater drainage system (e.g., ponds, tanks, and
bioswales) must also be maintained. If this maintenance is beyond your ability,
contractors are available to complete this work.
Stencil or apply catch basin/storm drain markers adjacent to storm drains to help
prevent the improper disposal of pollutants. If the catch basin grate is stamped with
warnings against polluting, then additional marking may not be required if there is
no evidence of pollutants being dumped or washed into the storm drain.
When painting stencils or installing markers, temporarily block the storm drain
inlet so that no pollutants are discharged from labelling activities.
Maintain the legibility of markers and signs.
Contact King County Stormwater Services at 206-477-4811 for a free stencil or
catch basin marker.
Connections to the stormwater drainage system that convey substances other than
stormwater are prohibited.
Illicit connections must be removed immediately, permanently plugged or re–
plumbed.
If the connection is re-plumbed, the line must discharge to the proper receiver, such
as the sanitary sewer, a septic system, an on–site treatment system, or a holding
tank for off–site disposal. There are restrictions on what can be disposed of to the
sanitary sewer and septic systems. Contact your sewer authority or Public Health –
Seattle and King County.
Unknown connections may require additional investigation to determine where all
stormwater and non–stormwater discharges go. This may include smoke, dye or
chemical testing, or closed-circuit television inspection. Contact King County
Stormwater Services at 206-477-4811 for further assistance.
Drainage facilities must meet the standards and requirements set forth in King
County’s Surface Water Design Manual for continual performance, operation, and
maintenance.
Additional Information
, Chapter 5: Information Sheets
Catch Basin Inserts
o
Disposal
o
Drainage Maintenance Contractors
o
Oil/Water Separator
o
-477-kingcounty.gov/stormwater
18
A-2:Outdoor Storage of Liquid Materials in Stationary
Tanks
The following best management practices (BMPs) apply to the outdoor storage of liquid
materials in stationary containers and indoor storage where the potential exists to flow
outside.
This does not apply to underground storage tanks or to businesses permitted by the
Washington State Department of Ecology to treat, store or dispose of dangerous wastes.
Storage of reactive, combustibles or flammable liquids must comply with the King County
Fire Code (KCC 17).
pollutants.
BMPs are required by King County Water Quality Code 9.12. If the BMPs included here are
not enough to prevent contamination of stormwater, you will be required to take additional
measures.
Required BMPs
Store and contain liquid materials so if the tank leaks, the contents will not get into
the stormwater drainage system, surface waters or groundwater. This requires
secondary containment or using a double–walled tank.
Place small, gravity–fed farm fuel tanks without secondary containment on flat and
open ground so that a spill or leak will not run downhill toward creeks, ditches, floor
drains or drain tiles before it can be contained and cleaned up.
Place tanks securely on stable ground.
Label all containers with the product name and associated hazards (e.g., flammable,
corrosive, toxic or reactive).
Install a spill control device (e.g., an oil/water separator or down–turned elbow) in
the catch basins that collect runoff from the tank storage area if the liquid is oil, gas,
or other material that separates from and floats on water.
Place drip pans or absorbent materials under taps and at all potential drip and spill
locations during filling and unloading of tanks. Properly dispose of collected liquids
and absorbent materials. Turn over empty drip pans when not in use of move under
cover.
Have spill cleanup materials/spill kit near the tanks and any liquid transfer areas.
Post a spill plan and keep contact information current.
Train all employees on spill response methods and procedures.
Required Routine Maintenance
Sweep and clean paved storage areas as needed. Do not hose down the area to a
storm drain.
19
Check tanks and sumps/catch basins regularly for leaks and spills. Collect and
dispose of all spilled liquids.
Inspect spill control devices regularly and remove floating oil and debris.
Collect and properly dispose of stormwater that collects in containment areas.
Additional Information
, Chapter 5: Information Sheets
Containment
o
Disposal
o
Oil/Water Separator
o
Spill Response and Cleanup Plan
o
–477–
kingcounty.gov/stormwater.
20
A-3:Storage of Liquid Materials in Portable Containers
The following best management practices (BMPs) apply to the outdoor storage of liquid
materials in portable containers and indoor storage where the potential exists to flow
outside.
Storage of reactive, combustibles or flammable liquids must comply with the King County
Fire Code (KCC 17). The local fire district must be consulted for limitations on clearance of
roof covers over containers used to store flammable materials.
BMPs are required by King County Water Quality Code 9.12. If the BMPs included here are
not enough to prevent contamination of stormwater, you will be required to take additional
measures.
Required BMPs
Place tight–fitting lids on all containers.
Enclose or cover the containers.
Raise containers off the ground with a spill containment pallet or similar method to
contain the material in the event of a spill or accident.
Place drip pans or absorbent materials under all potential drip and spill locations
during filling and unloading of containers. Properly dispose of collected liquids and
used absorbent materials. Turn over empty drip pans when not in use or move
under cover.
Do not use metal drums for liquid chemicals that are corrosive.
Label all containers with the product name and associated hazards (e.g., flammable,
corrosive, toxic or reactive).
Have spill cleanup materials/spill kit located nearby.
Have a spill plan with current contact information.
Train all employees on spill response methods and procedures.
Required Routine Maintenance
Sweep and clean the container storage areas as needed. Do not hose down the area
to the stormwater drainage system.
Routinely check containers and replace any compromised ones. Check nearby catch
basins to ensure nothing spilled into them. Dispose of all spilled liquids properly.
Inspect spill control devices routinely and properly remove and dispose of
accumulated oil and debris.
21
Storage of reactive, combustible, or flammable liquids must comply with the King
County Fire Code. The local fire district must be consulted for limitations on
clearance of roof covers over containers used to store flammable materials.
Additional Information
, Chapter 5: Information Sheets
Containment
o
Disposal
o
Spill Response and Cleanup Plan
o
–477–
kingcounty.gov/stormwater.
22
A-4:Outdoor Storage of Soil, Sand, and Other Erodible
Materials
The following best management practices (BMPs) apply to both permanent and temporary
sites. Contact between outside bulk materials and stormwater can cause leaching and
erosion of stored materials.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Cover and contain the stockpiled materials unless the material cannot wash into the
stormwater drainage system or surface waters and cannot be blown away by the
wind.
Covers must be in place at all times when the stockpile is not in active use.
Do not hose down the contained stockpile area to the stormwater drainage system.
For stockpiles greater than 5 cubic yards of erodible or water-soluble materials—
such as soil, road deicing salts, compost, unwashed sand and gravel, sawdust, and
bark—and for outside storage areas for solid leachable materials—such as freshly
treated lumber and metal products (excluding aluminum)—choose one or more of
the following BMPs:
Store in a building or paved and bermed covered area;
o
Place temporary plastic sheeting (e.g., polyethylene, polypropylene, Hypalon,
o
or equivalent) over the material;
Pave the area and install a drainage system. Place curbs or berms along the
o
perimeter of the area to prevent the run-on of uncontaminated stormwater
and to collect and convey all the runoff to treatment. Slope the paved area in
a manner that minimizes the contact between stormwater and leachable
materials (e.g., compost, logs, bark, wood chips);
For large uncovered stockpiles, implement containment practices at the
o
perimeter of the site and at any storm drains as needed to prevent erosion
and discharge from the stockpiled material off-site or to a storm drain.
Ensure that no direct discharge of contaminated stormwater to storm drains
exists without conveying runoff through an appropriate treatment BMP.
Catch basin inserts are not appropriate treatment for compost or road de-
icing salts.
Required Routine Maintenance
23
Sweep paved surfaces to collect solid materials. Do not hose down area to the
stormwater drainage system.
Check covers over the stockpiles to ensure they are still functioning properly.
Inspect and maintain catch basin inserts.
Additional Information
Manual, Chapter 5: Information Sheets
Catch Basin Insert
o
Containment
o
Covering
o
Manual, Appendix D: Construction Stormwater
Pollution Prevention Standards (Erosion Control Practices)
–477–
kingcounty.gov/stormwater.
24
A-5:Storage and Use of Pesticides and Fertilizers
The following best management practices (BMPs) apply to the storage and use of pesticides
and fertilizers. Pesticides include herbicides, rodenticides, insecticides, and fungicides.
Washington pesticide law requires most businesses that commercially apply pesticides to
the property of another to be licensed as a Commercial Applicator from the Washington
State Department of Agriculture.
For irrigation, landscaping, and vegetation maintenance, please refer to activity sheet A-26:
Landscaping Activities, Vegetation Maintenance, and Irrigation.
pollutants.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs: Storage
Store pesticides and fertilizers in impervious containment areas that prevent water
from coming into contact with the product.
Containment areas must be secured to prevent unauthorized personnel from
coming into contact with the materials.
Containers and bags must be covered, intact, and off the ground. If a container or
bag has been opened (including tears and punctures) or is showing signs of leakage,
secondary containment is also required.
Immediately clean up any spilled fertilizer or pesticides. Sweep paved storage areas
as needed. Collect and dispose of spilled materials. Do not hose down the area.
Keep pesticide and fertilizer contaminated waste materials in designated covered
and contained areas.
Dispose of contaminated pesticide and fertilizer waste materials properly.
Store and maintain spill cleanup materials near the storage area.
Do not discharge spills, leaks or stormwater containing pesticides or fertilizers to
the stormwater drainage systems or to the sanitary sewer. Unused product,
stormwater contaminated with pesticides and/or fertilizers, and spilled material
must be collected and disposed of properly, according to the product label.
Required BMPs: Fertilizer Application
Never apply fertilizers if it is raining or about to rain. The longer the period between
fertilizer application and either rainfall or irrigation, the less fertilizer runoff occurs.
Determine the proper fertilizer application for the types of soil and vegetation
involved.
25
Follow manufacturers’ recommendations and label directions.
Train employees on the proper use and application of fertilizers.
Keep fertilizer granules off of impervious surfaces. Clean up any spills immediately.
Do not hose down any spilled pesticide or fertilizer to a storm drain, conveyance
ditch, or surface waters.
If possible, do not fertilize areas within 100 feet of water bodies including wetlands,
ponds, and streams.
Avoid fertilizer applications in stormwater drainage systems, including ditches
ponds and swales.
Unless approved by the local jurisdiction, do not apply fertilizer at commercial and
industrial facilities, to grass swales, buffer areas or filter strips if the area drains to
sensitive water bodies.
Apply fertilizers in amounts appropriate for the targetvegetation and at the time of
year that minimizes losses to surface and ground waters.
Supplemental BMPs: Fertilizer Application
Apply the minimum amount of slow-release fertilizer necessary to achieve
successful plant establishment.
Do not fertilize when the soil is dry or during a drought.
Test soils to determine the correct fertilizer application rates.
Evaluation of soil nutrient levels through regular testing ensures the best possible
efficiency and economy of fertilization.
Fertilization needs vary by site depending on plant, soil, and climatic conditions.
Choose organic fertilizers when possible.
Use slow-release fertilizers such as methylene urea, isobutylidene, or resin coated
fertilizers when appropriate, generally in the spring. Use of slow-release fertilizers
is especially important in areas with sandy or gravelly soils.
Time the fertilizer application to periods of maximum plant uptake. Washington
State Department of Ecology generally recommends application in the fall and
spring, although Washington State University turf specialists recommend four
fertilizer applications per year.
Do not use turf fertilizers containing phosphorous unless a soil sample analysis
taken within the past 36 months that indicates the soil of the established lawn is
deficient in phosphorus. For more information about restrictions on turf fertilizers
containing phosphorus, visit the Washington State Department of Agriculture’s
website https://agr.wa.gov/departments/pesticides-and-
fertilizers/fertilizers/fertilizers-containing-phosphorus
Required BMPs: Pesticide Application
All procedures shall conform to the requirements of Chapter 17.21 RCW and
Chapter16-228 WAC.
26
Train employees on proper application of pesticides and disposal practices.
Follow manufacturers’ application guidelines and label requirements.
Avoid excessive application of chemicals. Do not apply pesticides in quantities that
exceed the limits on the product’s Federal Insecticide, Fungicide, and Rodenticide
Act (FIFRA) label.
Conduct spray applications during weather conditions as specified on the label
requirements and applicable local and state regulations. Do not apply during rain or
immediately before expected rain (unless the label directs such timing).
Clean up any spilled pesticides immediately. Do not hose down to a storm drain,
conveyance ditch, or surface water.
Flag all sensitive areas including wells, creeks, and wetlands prior to spraying.
Post notices and delineate the spray area prior to the application, as required by the
local jurisdiction, or by the Washington State Department of Ecology.
Mix pesticides and clean the application equipment under cover in an area where
accidental spills will not enter surface or ground waters, and will not contaminate
the soil.
Follow the FIFRA label requirements for disposal. If the FIFRA label does not have
disposal requirements, the rinseate from equipment cleaning and/or triple-rinsing
of pesticide containers should be used as product or recycled into product.
Collect the equipment wash water (rinseate) and store it in a labelled leakproof
container with a lid. Reuse the wash water when making another spray mixture of
the same pesticide. Do not mix different pesticide wash waters. Do not dump the
wash water down a storm drain, to a conveyance ditch, surface water or to the
ground. Unused wash water will most likely be a regulated hazardous waste,
requiring special disposal.
The pesticide application equipment must be capable of immediate shutoff in the
event of an emergency.
Supplemental BMPs: Pesticide Application
Use manual pest control strategies, such as physically scraping moss from rooftops
and using rodent traps.
Remove weeds/vegetation in stormwater ditches, detention ponds and drainage
swales by hand or other mechanical means.
Use pesticides only as a last resort. Consider alternatives to the use of pesticides
such as:
Covering or harvesting weeds, substitute vegetative growth, and manual
o
weed control/moss removal.
Soil amendments, such as compost, that are known to control some common
o
diseases in plants, such as Pythium root rot, ashy stem blight, and parasitic
nematodes.
Implement a pest-use plan which should include at a minimum:
27
A list of selected pesticides and their specific uses.
o
Brands and formulations of the pesticides.
o
Application methods and quantities to be used.
o
Equipment useand maintenance procedures.
o
Safety, storage, and disposal methods.
o
Monitoring, record keeping, and public notice procedures.
o
Develop and implement an Integrated Pest Management (IPM) program if pests are
present. The following steps are adapted from Least
Lawns, written by Sheila Daar.
Step One: Correctly identify problem pests and understand their life cycle.
o
Learn more about the pest.
Observe it and pay attention to any damage that may be occurring.
Learn about the life cycle.
Many pests are only a problem during certain seasons, or can only be
treated effectively in certain phases of the life cycle.
Step Two: Establish tolerance thresholds for pests.
o
Decide on the level of infestation that must be exceeded before
treatment needs to be considered. Pest populations under this
threshold should be monitored but don’t need treatment.
Step Three: Monitor to detect and prevent pest problems.
o
Monitor regularly to anticipate and prevent major pest outbreaks.
Conduct a visual evaluation of the lawn or landscape's condition. Take
a few minutes before mowing to walk around and look for problems.
Keep a notebook, record when and where a problem occurs, then
monitor for it at about the same time in future years.
Specific monitoring techniques can be used in the appropriate season
for some potential problem pests, such as European crane fly.
Step Four: Modify the maintenance program to promote healthy plants and
o
dis-courage pests.
Review your landscape maintenance practices to see if they can be
modified to prevent or reduce the problem.
A healthy landscape is resistant to most pest problems. Lawn aeration
and over-seeding along with proper mowing height, fertilization, and
irrigation will help the grass out-compete weeds.
Correcting drainage problems and letting soil dry out between
waterings in the summer may reduce the number of crane-fly larvae
that survive.
Step Five: If pests exceed the tolerance thresholds:
o
28
Consider the most effective management options concurrent with
reducing impacts to the environment. This may mean chemical
pesticides are the best option in some circumstances.
Consider the use of physical, mechanical, or biological controls.
Study to determine what products are available and choose a product
that is the least toxic and has the least non-target impact.
Step Six: Evaluate and record the effectiveness of the control, and modify
o
maintenance practices to support lawn or landscape recovery and prevent
recurrence.
Keep records!
Note when, where, and what symptoms occurred, or when monitoring
revealed a potential pest problem.
Note what controls were applied and when, and the effectiveness of
the control.
Monitor next year for the same problems.
Conduct any pest control activity at the life stage when the pest is most vulnerable.
For example, if it is necessary to use a Bacillus thuringiens application to control
tent caterpillars, apply it to the material before the caterpillars cocoon or it will be
ineffective. Any method used should be site-specific and not used wholesale over a
wide area.
Choose pesticides categorized by the EPA as reduced risk, such as the herbicide
imazamox, and choose the least toxic pesticide available that is capable of reducing
the infestation to acceptable levels. The pesticide should readily degrade in the
environment and/or have properties that strongly bind it to the soil.
When possible, apply pesticides during the dry season so that the pesticide residue
is degraded prior to the next rain event.
If possible, do not spray pesticides within 100 feet of water bodies. Spraying
pesticides within 100 feet of water bodies including any drainage ditch or channel
that leads to open water may have additional regulatory requirements beyond just
following the pesticide product label. Additional requirements may include:
Obtaining a discharge permit from the Washington State Department of
o
Ecology.
Obtaining a permit from the local jurisdiction.
o
Using an aquatic labeled pesticide and adjuvant.
o
Once a pesticide is applied, evaluate its effectiveness for possible improvement.
Records should be kept showing the effectiveness of the pesticides applied.
Develop an adaptive management plan and annual evaluation procedure including:
(adapted from Daar’s )
A review of the effectiveness of pesticide applications.
o
29
Impact on buffers and sensitive areas, including potable wells. If individual or
o
public potable wells are located in the proximity of commercial pesticide
applications, contact the regional Ecology hydrogeologist to determine if
additional pesticide application control measures are necessary.
Public concerns.
o
Recent toxicological information on pesticides used/proposed for use.
o
Additional Information
Stormwate, Chapter 3: Commercial and Multifamily
BMPs
A-2: Outdoor Storage of Liquid Materials in Stationary Tanks
o
A-3: Storage of Liquid Materials in Portable Containers
o
A-26: Landscaping Activities, Vegetation Management, and Irrigation
o
, Chapter 5: Information Sheets
Containment
o
Covering
o
Disposal
o
For soils testing, contact the King Conservation District (425-282-1900 or
district@kingcd.org, a soils testing professional, or a Washington State University
Extension office, 206-205-3100.
Comply with WAC 16-228 (General Pesticide Rules) and WAC 16-229 (Secondary
and Operational Area Containment for Bulk Pesticides).
For more information, refer to the Pesticide Information Center Online (PICOL)
Databases at https://picol.cahnrs.wsu.edu/
–477–
kingcounty.gov/stormwater.
30
A-6:Storage of Contaminated Soils
The following best management practices (BMPs) apply to the storage and/or treatment of
contaminated soils such as those excavated during underground fuel tank removal or on-
site soil remediation.
The Washington State Department of Ecology regulates businesses engaged in this activity.
In addition, a permit from the Puget Sound Clean Air Agency is required if the treatment
method for removing soil contaminants involves forcing air through the soil.
can
BMPs are required by King County Water Quality Code 9.12. If the BMPs included here are
not enough to prevent contamination of stormwater, you will be required to take additional
measures.
Required BMPs
Cover contaminated soils to keep them from coming into contact with stormwater.
Contain the material so that nothing flows into or out of the stockpile.
Required Routine Maintenance
Sweep paved storage areas as needed. Collect and dispose of soil particles. Do not
hose down the area.
Stock cleanup materials near the storage area.
Additional Information
, Chapter 5: Information Sheets
Containment
o
Covering
o
–477–
kingcounty.gov/stormwater.
31
A-7:Food and Beverage Manufacturing and Storage
The following best management practices (BMPs) apply to the outdoor storage and/or
processing of raw materials for food or beverage items prior to or after packing,
processing, or sale, or that crush, cut, ferment, distill orshred food items for fermented
beverages, juices, and other food and beverage products.
Additional BMPs may be required for wineries covered under the Washington State
Department of Ecology’s Winery general permit. Brewery, distillery, cidery general permits
may be created by the Department of Ecology in the future. Contact the Department of
Ecology’s Northwest Regional Office at 206-594-0000for more information.
Potential pollutants can include but are not limited to nutrients, oxygen demanding
substances, and sediment.
BMPs are required by King County Water Quality Code 9.12. If the BMPs included here are
not enough to prevent contamination of stormwater, you will be required to take additional
measures.
Required BMPs – Temporary Outdoor Storage
Train employees to keep a clean storage area.
Store all food and beverage items in leak-proof containers. The edge of the container
should be higher than the items stored within. Do not allow food items to drape over
the side of the container.
Make sure all outside materials that have the potential to leach or spill to the
stormwater drainage system are covered, contained, or moved to an indoor location.
For fruits, vegetables, and grains stored outside for a week or more, cover with a
tarp or other waterproof material. Make sure coverings are secured from wind.
Do not drain water or ice that was in contact with food or beverage items to the
stormwater drainage system.
Dispose of perished items in a timely manner.
Stock cleanup materials, such as brooms and dustpans, near the storage area.
Sweep and/or pick up dirt and food fragments daily. Place collected waste in
covered leak-proof containers prior to disposal. Do not hose down the storage area
to the stormwater drainage system. If water is used for clean-up, it must be
collected and treated as wastewater.
Required BMPs – Processing
Enclose the processing area in a building or shed or cover the area to prevent
stormwater run-on. Pave and slope the processing area to capture the water used
for cleaning, rinsing, and processing. Collect all wastewater and drain to a holding
tank, the sanitary seweror other treatment facility.
Do not discharge the wastewater to the stormwater drainage system or to ground.
32
If a holding tank is used for the storage of wastewater, pump out the contents before
the tank is full and dispose of the wastewater to the sanitary sewer or an approved
wastewater treatment system.
Required BMPs – Wineries, Breweries, Distilleries and Cideries
Wastewater may not be discharged to the stormwaterdrainage system, surface
waters or an on-site septic system.
Implement a waste management plan that includes how to manage and dispose of
all solid organic waste and wastewater created by production, cleaning, rinsing, and
bottling and shall include the following:
Identification of all solid and liquid waste streams and what steps in the
o
process they are generated;
How these waste streams will be collected, stored, and disposed of; and
o
Spill prevention and clean up procedures.
o
Disposal options include:
Solid organic wastes
o
On-site composting
Off-site composting
Animal feedstock
Wastewater
o
Animal feedstock – contact Washington State Department of
Agriculture for approval.
Sewer discharge – contact King County Industrial Waste for approval.
Land treatment systems – the controlled application of wastewater to
irrigation lands for treatment. Irrigation to managed vegetation
includes discharging to crops, landscaped areas, or other vegetated
areas as long as the vegetation is healthy and maintained. Contact
Washington State Department of Ecology for approval.
Infiltration basin: A structure where treated wastewater is discharged
and allowed to infiltrate to ground. Contact Washington State
Department of Ecology for approval.
Subsurface Infiltration: An onsite system that treats wastewater
before discharging it to a drain field where additional treatment
occurs. This is a separate system from a domestic onsite sewage
system (septic system). Contact Washington State Department of
Ecology for approval.
Supplemental BMPs
Cover outdoor storage areas.
Use a containment curb, dike, or berm to prevent off-site runoff from storage or
processing areas and to prevent stormwater run-on
33
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-8: Storage of Solid Waste and Food Waste (Including Cooking Grease)
o
A-12: Cleaning or Washing of Food Service Areas and Equipment
o
, Chapter 5: Information Sheets
Containment
o
Controlling and Collecting Contaminated Runoff
o
Covering
o
Disposal
o
Contact the local sewer authority and the King County Wastewater Treatment
Division Industrial Waste Section at 206-477-5371 for more information on disposal
to the sanitary sewer system.
–477–
kingcounty.gov/stormwater.
34
A-8:Storage of Solid Waste and Food Wastes (Including
Cooking Grease)
The following best management practices (BMPs) apply to garbage dumpsters, trash
compactors and outdoor waste containers (e.g., cooking oil/grease receptacles).
pollutants.
BMPs are required by King County Water Quality Code 9.12. If the BMPs included here are
not enough to prevent contamination of stormwater, you will be required to take additional
measures.
Required BMPs
Store wastes in leak-proof containers with solid lids (e.g., dumpsters and trash
compactors). No rainwater should be able to enter the container and no fluids
should be leaking out.
Keep all waste receptacles (e.g., dumpsters, garbage cans, used cooking oil/grease
containers) closed except when adding waste.
Leaking outdoor waste containers must be repaired or replaced. Contact your waste
hauler for replacements if the container is leased.
Trash compactor wastewater must be discharged to the sanitary sewer, septic
system or collected and hauled off-site for proper disposal. It must not be
discharged to ground, stormwater drainage systems, surface waters or
groundwater.
Trash compactor drain lines should be connected to the sanitary sewer or septic
system. If a connection is not possible, collect the wastewater in a dead-end sump or
similar device. The wastewater containment must be easily inspected, maintained,
and pumped out for proper disposal.
Used cooking oil/grease containers should be labeled with their contents and have a
secured lid.
While oil/grease containers are not required to have secondary containment, they
should be located and/or secured such that they can’t be tipped over.
Clean up any spills immediately using absorbent material or scraping it up. Grease
cannot be left on the ground.
Have spill cleanup materials nearby.
Use a lid or cover when transporting cooking oil/grease containers from kitchens to
outside grease containers to prevent contents from spilling.
Ensure that drip pans or absorbent materials are used whenever grease containers
are emptied by vacuum trucks or other means.
35
Dispose of collected cooking oil/grease as garbage if it is not being recycled. Do not
dispose of fats, oils, or grease (FOG) into the sanitary sewer, septic system, or
stormwater drainage system.
Required Routine Maintenance
Keep the area around the grease container cleanand free of debris.
Check storage containers frequently for leaks and to ensure that lids are secure.
Regularly check for loose debris in the waste container storage area and sweep if
the area is paved. After sweeping, the waste storage area may be hosed down—
without the use of soaps, detergents, or other chemicals—if there are no
accumulations of oil and grease present and the rinse water is not discharged to a
stormwater drainage system or surface water. The rinse water can infiltrate to
ground or be discharged to a sanitary sewer.
Do not hose down or apply soaps, detergents,or other chemicals to waste storage
areas with accumulated oil and grease. Oily wastewater can clog stormwater
drainage systems and sanitary sewer lines. Contact a service provider to remove
and properly dispose of oil and grease accumulations.
If cleaning or rinsing waste containers, dispose of all wastewater into the sanitary
sewer. If sanitary sewer is not available, then store the wastewater in a holding tank,
dead-end sump, or truck it off-site to an approved disposal location.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-31: Parking Lots, Driveways and Outside Storage Areas
o
, Chapter 5: Information Sheets
Disposal
o
Drainage Maintenance Contractors
o
–477–
kingcounty.gov/stormwater.
36
A-9:Storage of Scrap and Recycling Materials (Including
Auto Recycling Facilities)
The following best management practices (BMPs) apply to the salvaging and storage of
scrap metal, scrapped equipment, junked appliance and vehicles, empty metal drums, and
recyclable materials such as cans, bottle, plastic, and paper products.
P
BMPs are required by King County Water Quality Code 9.12. If the BMPs included here are
not enough to prevent contamination of stormwater, you will be required to take additional
measures.
Required BMPs
Check incoming scrap materials, vehicles, and equipment for potential fluid contents
and batteries.
Drain and transfer fluids from vehicles and other equipment only in a designated
area with a waste collection system or over drip pans.
Cover and contain vehicle and equipment dismantling areas to prevent rainwater
contact.
Remove batteries and store off the ground in a leak proof container and under
cover.
Cover and raise any materials that may contaminate stormwater. A tarp and a pallet
are acceptable.
Cover and contain stockpiles of any material that has the potential to contaminate
stormwater runoff.
All containers used to store fluids must comply with activity sheets A-2: Outdoor
Storage of Liquid Materials in Stationary Tanks and A-3: Outdoor Storage of Liquid
Materials in Portable Containers regarding secondary containment. Storage of
gasoline must comply with the appropriate Fire Codes.
Required Routine Maintenance
Inspect storage areas regularly and promptly clean up any leaks, spills, or
contamination.
Sweep scrap storage areas as needed. Do not hose down anything to the stormwater
drainage system.
Keep spill cleanup materials in a location known to all. Ensure that employees are
familiar with the site’s spill control plan and/or proper spill cleanup procedures.
If you are involved in transporting any of these materials you must carry spill
cleanup material in the vehicle to capture any spilled liquids, and have an
impermeable liner in the bed of your truck to capture any spilled or leaked
materials. Properly dispose of or reuse any collected fluids.
37
Supplemental BMPs
Install catch basin inserts to collect excess sediment and debris if necessary. Inspect
and maintain catch basin inserts to ensure they are working correctly.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-2: Outdoor Storage of Liquid Materials in Stationary Tanks
o
A-3: Outdoor Storage of Liquid Materials in Portable Containers
o
, Chapter 5: Information Sheets
Catch Basin Inserts
o
Containment
o
Covering
o
–477–
kingcounty.gov/stormwater.
38
A-10:Treatment, Storage or Disposal of Dangerous Wastes
.
This activity applies to businesses that are permitted by the Washington State Department
of Ecology to treat, store, or dispose of dangerous wastes.
pollutants.
BMPs are required by King County Water Quality Code 9.12. If the BMPs included here are
not enough to prevent contamination of stormwater, you will be required to take additional
measures.
Required BMPs
Detailed BMPs are not included here because treatment, storage, and disposal (TSD)
site requirements are beyond the level of typical BMP application.
Department of Ecology regulates these facilities with specific requirements, which
include the need for a National Pollutant Discharge Elimination System (NPDES)
permit
Additional Information
, Chapter 5: Information Sheets
Spill Response and Cleanup Plan
o
Contact Ecology at 206-594-0000 or 360-407-6000
–477–
kingcounty.gov/stormwater.
39
A-11:Cleaning or Washing of Tools and Equipment
The following best management practices (BMPs) apply to the cleaning of tools and
equipment such as lawn mowers, edgers and grass trimmers, tools used at equipment
repair shops, and manufacturing equipment such as saws, grinders, and screens.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Discharge tool and equipment wash water to the sanitary sewer (with approval
from the sewer authority) or a holding tank for offsite disposal. The discharge of
wash water to the stormwater drain system is not allowed without treatment and
an Individual Wastewater Discharge permit from the Washington State Department
of Ecology.
Rinse lawnmowers with water only on a lawnor similar area where grass clippings
will not get into the stormwater drainage system or surface waters when it rains.
Oily, soapy, or otherwise dirty water is not allowed to discharge to any stormwater
drainage system or surface water.
Supplemental BMPs
Recycle your wash water with an enclosed loop system or use self-contained parts
washers. Numerous products are commercially available that recycle and contain
wash water and cleaning solvents.
Additional Information
Preventio, Chapter 3: Commercial and Multifamily
BMPs
A-13: Vehicle Washing and Steam Cleaning
o
A-18: Vehicle and Equipment Repair and Maintenance
o
, Chapter 5: Information Sheets
Containment
o
Disposal
o
Oil/Water Separator
o
Water Quality Treatment BMP
o
Washington State Department of Ecology’s Vehicle and Equipment Washwater
Discharges/Best Management Practices Manual
https://fortress.wa.gov/ecy/publications/summarypages/95056.html
40
–477–
kingcounty.gov/stormwater.
41
A-12:Cleaning of Washing of Food Service Areas and
Equipment
The following best management practices (BMPs) apply to stationary and mobile
operations.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
The cleaning of food service equipment—such as cooking equipment, filter screens,
and floor mats—must be done indoors.
All wash and rinse water (including mop water) must be discharged to the sanitary
sewer or the septic system. It may not be discharged outdoors or into the
stormwater drainage system.
Floor mop water must not be poured outside. Instead pour mop water into a mop
sink, utility sink or toilet.
Wash and rinse water containing fats, oils, or grease (FOG) may require
pretreatment to remove FOG prior to disposal to the sanitary sewer or septic
system. Check with your sewer authority or Public Health-Seattle and King County.
Do not dispose of wash or rinse waster containing floor stripping or disinfectant
chemicals into the septic system as they can seriously inhibit wastewater treatment
and cause the system to fail. The wash or rinse water should be collected and hauled
offsite for proper disposal (e.g., taken to a wastewater treatment facility).
The use of “environmentally friendly”, "nontoxic" or “biodegradable” soaps and
detergents does NOT make it acceptable to discharge to any stormwater drain
system or surface waters. All soaps and detergents are harmful to aquatic
organisms.
Additional Information
Contact Public Health-Seattle and King County at 206-263-9566 or 206-477-8050
Contact the local sewer authority and the King County Wastewater Treatment
Division Industrial Waste Section at 206-477-5371 for more information on disposal
to the sanitary sewer system.
Interagency Resource for Achieving Cooperation’s
Management https://apps.lhwmp.org/IRAC/eDoc.ashx?DocID=Xb9va1HRGBg%3d
–477–
kingcounty.gov/stormwater.
42
A-13:Vehicle Washing and Steam Cleaning
The following best management practices (BMPs) apply to all vehicle washing including
mobile vehicle washing and detailing services, firefighting equipment, and fleet
maintenance. For exterior vessel washing refer to activity sheet A-30: Marine Activities.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Commercial and fleet car washing and detailing must be done in a contained area
where all water is collected and either recycled or discharged to the sanitary sewer.
Occasional vehicle washing (less than 5 vehicles, 1-2 times a month) with a mild (pH
neutral) soap or detergent on gravel, grass, or loose soil is allowed as long as all the
water soaks into the ground (with no possibility of the wash water getting into the
stormwater drainage system) and you only wash the exterior (not the engine
compartment or undercarriage)of the vehicle.
The use of “environmentally friendly”, "nontoxic" or “biodegradable” soaps and
detergents does NOT make it acceptable to discharge vehicle wash water to any
stormwater drain system or surface waters. All soaps and detergents are harmful to
aquatic organisms.
If your business is located in an area designated as a critical aquifer recharge area
(CARA), infiltration may not be allowed. For additional information on critical
aquifer recharge areas in King County, refer to King County Code 21A.24.311-316.
Do not wash or rinse vehicles on permeable pavement or pavers.
Do not wash vehicles on impermeable (conventional) paved areas or wash or rinse
the engine compartment or the underside of vehicles, unless you do one of the
following:
Designate a wash area for all vehicles where the wash water is collected and
o
discharged to the sanitary sewer or is processed through an enclosed
recycling system;
Use a portable collection system that captures all the wash water for proper
o
disposal; or
For the occasional washing of the exterior (not the engine compartment or
o
undercarriage) of vehicles (less than 5 vehicles, 1-2 times a month), ensure
that the paved area drains directly to grass, gravel or loose soil and there is
no possibility of the wash water getting into the stormwater drainage system
Do not conduct oil changes or other engine maintenance in the designated washing
area.
43
Rinsing the outside of a vehicle with water and without any soaps or detergents is
allowed as long as the water is filtered prior to discharge to the stormwater
drainage system.
At multifamily properties it may be necessary to post signs at the designated wash
areas, indicating where and how vehicle washing must be done.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-30: Marine Activities
o
, Chapter 5: Information Sheets
Catch Basin Inserts
o
Disposal
o
Washington State Department of Ecology’s Vehicle and Equipment Wash Water
Discharges/Best Management Practices Manual
https://fortress.wa.gov/ecy/publications/summarypages/95056.html
–477–
kingcounty.gov/stormwater.
44
A-14:Interior Washing Operations (Including Mobile
Contractors)
Best management practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of stormwater,
you will be required to take additional measures.
Required BMPs
All wash and rinse water (including floor mop water) must be discharged to the
sanitary sewer or septic system. It may not be discharged outdoors or into the
stormwater drainage system.
Do not dispose of wash or rinse waster containing floor stripping or disinfectant
chemicals into the septic system as they can seriously inhibit wastewater treatment
and cause the system to fail. The wash or rinse water should be collected and hauled
offsite for proper disposal (e.g., taken to a wastewater treatment facility).
The use of “environmentally friendly”, "nontoxic" or “biodegradable” soaps and
detergents does NOT make it acceptable to discharge to any stormwater drain
system or surface waters. All soaps are harmful to aquatic organisms.
Do not dispose of sludge (thick, wet, viscous mixture; e.g., accumulated food debris
cleaned from surface of equipment) outdoors or into the stormwater drainage
system.
Additional Information
, Chapter 5: Information Sheets
Disposal
o
Contact the local sewer authority and the King County Wastewater Treatment
Division Industrial Waste Section at 206-477-5371 for more information on disposal
to the sanitary sewer system.
–477–
kingcounty.gov/stormwater.
45
A-15:Washing of Buildings, Rooftops, and Other Large
Surfaces
The following best management practices (BMPs) apply to the washing of objects not
associated with the operation or storage of automotive equipment or machinery.
For washing of parking lots, driveways, or other areas where automotive fluid (e.g., oil,
gasoline) are present, see activity sheet A-31: Parking Lots, Driveways, and Outside Storage
Areas. For washing of docks, wharves, piers, floats, and boat ramps, see activity sheet A-30:
Marine Activities.
g
Best Management Practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of stormwater,
you will be required to take additional measures.
Required BMPs
If soaps, detergents, or any other chemicals are used, use a sump pump, wet vacuum
or similar device that enables collection of wash water and associated solids so they
can be disposed of properly. The wash water must not go to the stormwater
drainage system, groundwater, or surface water. This may require temporarily
blocking or disconnecting downspouts from the stormwater drainage system in
order to prevent illicit discharges.
Wash water runoff does not have to be collected if:
No soaps, detergents, or any other chemical (including pesticides) are used;
o
Only cold water is used. Heated water cannot be discharged to the
o
stormwater drainage system; and
the wash water can be diverted to a nearby vegetated area to
infiltrate into the ground, or
the wash water is filtered through media (e.g., filter fabric) to trap
solid materials, prior to entering a stormwater drainage system. The
area must be swept prior to washing, in order to remove all fines (e.g.,
silts and clay) that may otherwise clog or bypass the filtering process.
Oil stains must be removed with absorbent materials prior to washing
Wash water is not allowed to flow off-site.
If the surface being washed has lead or other heavy metal-bearing paint or dust
(such as chromium or cadmium), you must use a commercial washing service that
will collect, test, and properly dispose of the wash water.
46
Block or disconnect all rooftop downspouts when washing roofs. The wash water
must be directed to pervious areas such as landscaping or gravel for infiltration,
collected and disposed of to the sanitary sewer, or taken off-site for proper disposal.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-30: Marine Activities
o
A-31: Parking Lots, Driveways and Outside Storage Areas
o
, Chapter 5: Information Sheets
Catch Basin Insert
o
Disposal
o
Note:Was
locations.
–477–
kingcounty.gov/stormwater.
47
A-16:Truck or Rail Loading and Unloading of Liquid or Solid
Material
Best management practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of stormwater,
you will be required to take additional measures.
Required BMPs
Place drip pans underneath hose and pipe connections and other leak-prone spots
during liquid transfer operations, and when making and breaking connections.
Immediately clean up any material that has spilled during transfer operations.
Have a current spill control plan.
Train employees to follow proper loading and unloading procedures. Ensure that
employees are familiar with the site’s spill response and cleanup plans and/or
proper spill cleanup procedures.
Store and maintain appropriate spill cleanup materials in a location known to all.
Conduct loading and unloading operations under cover if possible.
Required Routine Maintenance BMPs
Clean drip pans as needed and dispose of contents properly.
Check equipment for leaks on a regular basis and repair if needed.
Sweep loading/unloading areas as needed. Neverwash anything to the stormwater
drainage system or the street.
Supplemental BMPs
Pave areas where liquids are transferred to and from tanker trucks. Use Portland
cement concrete for fuels that react with asphalt, such as gasoline.
Install a curb or dike, or slope the area to prevent stormwater from running on to
the loading/unloading area and washing away spilled material.
Additional Information
, Chapter 5: Information Sheets
Disposal
o
Spill Response and Cleanup Plan
o
–477–
kingcounty.gov/stormwater.
48
A-17:Stationary Fueling Operations
The following best management practices (BMPs) apply to the fueling of vehicles and
equipment, including gas stations and fuel pumps to service equipment or vehicles, where
the fuel pumps were constructed or substantially remodeled after July 1995. “Substantial
remodeling” means replacing the canopy, adding fuel tanks, or relocating or adding one or
more fuel dispensers in such a way that modifies the impervious concrete paving in the
fueling area.
For fueling operations installed prior to July 1995, see activity sheet A-47: Older Stationary
Fueling Operations. For mobile fueling operations see activity sheet A-48: Mobile Fueling of
Vehicles and Heavy Equipment. For in-water and over-water fueling operations, see
activity sheet A-30: Marine Activities.
All BMPs related to fueling must be consistent with the requirements of the King County
Fire Code (KCC 17.04). The water quality requirements presented in this manual are
separate from, and in addition to, the requirements of the King County Fire Code.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Design the fueling island to minimize stormwater contamination, to control spills,
and to collect and direct contaminated stormwater and/or wastewater for
treatment.
The fueling island must have a roof or canopy to prevent the direct entry of
precipitation onto the spill containment pad. At a minimum, cover the spill
containment pad (within the grade break or fuel dispensing area) and extend
several additional feet to reduce the introduction of windblown rain.
Roofs and canopies 10 feet or less in height must have a minimum overhang
o
of 3 feet on all sides.
Roofs and canopies greater than 10 feet in height mush have a minimum
o
overhand of 5 feet on each side.
Convey runoff collected from the roof and canopy to a stormwater drainage system
or receiving water outside of the spill containment pad. This will prevent mixing of
uncontaminated runoff from the roof or canopy with contaminated runoff collected
on the spill containment pad.
Design the fueling island as a spill containment pad with a sill or berm, raised to a
minimum of four inches, to prevent the runoff of spilled liquids and to prevent the
49
run-on of stormwater from the surround area. Raised sills are not required at the
open-grate trenches that connect to an approved drainage-control system.
The spill containment pad must be constructed of impervious concrete. Asphalt is
not acceptable.
Slope the spill containment pad around the fueling island towards the spill
containment pad drains; either trench drains, catch basins and/or a dead-end sump.
The slope of the drains shall not be less than 1 percent.
Drains from the spill containment pad must have a normally closed shutoff valve.
The valve may be opened to convey stormwater with residual contamination to an
oil control treatment system (e.g., oil/water separator, catch basin insert, or
equivalent treatment) which then discharges to:
at a minimum, a basic treatment system (e.g., sand filter, filter strips, water
o
quality vault) prior to discharging to a storm drainage system, surface water
or ground, or
a sanitary sewer. Approval from the local sewer authority is required for
o
conveyance of any fuel-contaminated stormwater to a sanitary sewer. State
and local regulations prohibit discharges that could cause a fire or explosion
(WAC, Section 173-216-060; KCC 28.84.060). For conveyance to the sanitary
sewer, a catch basin shall be installed upstream of the oil control treatment
system, and a normally closed shutoff valve is required at the discharge point
of the oil control treatment system.
In the case of a fuel spill, spilled fuel must be pumped from the drains or catch
basins and must be treated and disposed of offsite in accordance with Department
of Ecology regulations. The valve may only then be opened to convey stormwater
with residual contamination.
Discharges from the treatment systems (oil control treatment and basic treatment
system) to storm drainage systems, sanitary sewer, surface water or to the ground
must not display ongoing or recurring visible sheen and must not contain oil or
grease.
Alternatively, collect runoff from the spill containment pad in a dead-end sump and
hold for proper off-site disposal. The dead-end sump must be easily inspected,
maintained, and pumped.
The minimum spill retention volume of the oil control treatment system or dead-
end sump shall be:
15 minutes for the flow rate of the dispensing mechanism with the highest
o
through-put rate, or
if the area is uncovered, the 15-minute peak flow rate of the 6-month, 24-
o
hour storm event over the surface of the spill containment pad – whichever is
greater.
The volume of the dead-end sump shall be a minimum of 50 gallons with an
o
adequate grit sedimentation volume.
50
Additional Required BMPs for Vehicles or Equipment 10 feet in height or greater
A roof or canopy may not be feasible at fueling stations that regularly fuel vehicles or
equipment that are 10 feet in height or greater. At those types of fueling facilities, the
following BMPs apply, as well as other applicable BMPs for fueling stations:
If a roof or canopy is infeasible, then the concrete fueling pad must be equipped with
emergency spill control features including a shutoff valve for drainage from the
fueling area. The drainage shutoff valve may be kept open to convey stormwater
with residual contamination from the fueling pad.
Maintain the valve in the closed position during a spill event and cleanup. An
electronically actuated valve is preferred to minimize the time lapse between spill
and containment.
In the case of a fuel spill, spilled fuel must be pumped from the drains or catch
basins and must be treated and disposed of offsite in accordance with Department
of Ecology regulations. The valve may only then be reopened to convey stormwater
with residual contamination.:
to a sanitary sewer, if approved by the sewer authority, or
o
to an oil control treatment system (e.g., an oil/water separator, catch basin
o
insert, or equivalent treatment), and then, at a minimum, to a basic treatment
system (e.g., sand filter, filter strips, water quality vault). Discharges from
treatment systems to stormwater drainage systems, sanitary sewer or
surface water must not display ongoing or recurring visible sheen and must
not contain oil or grease.
Required Operational BMPs
Train employees on the proper use of fuel dispensers.
Post signs in accordance with the Uniform Fire Code (UFC) or International Fire
Code (IFC). Post “No Topping Off” signs. Topping off fuel tanks results in spillage and
vents gasoline fumes to the air.
The person conducting the fuel transfer must be present at the fueling pump during
fuel transfer. It is encouraged to post “Stay with Vehicle During Fueling” signage
near fuel dispensers.
Make sure that the automatic shutoff on the fuel nozzle is functioning properly.
Prepare an emergency spill response and cleanup plan. Have designated trained
person(s) available either on-site or on call at all times to implement the plan
promptly and properly and immediately cleanup all spills.
Keep suitable cleanup materials, such as dry adsorbent materials, on-site to allow
prompt cleanup of a spill. Do not use dispersants or soap to clean up spills or sheens.
Immediately notify Ecology, the local jurisdiction,and the local sewer authority if a
spill reaches sanitary or storm sewers, ground water, or surface water, in
accordance with federal and Ecology spill reporting requirements.
51
Sweep or vacuum the fueling area as needed to collect sediment and debris. Never
hose down the fueling area to the storm drains. Contaminated runoff and spills
must be collected for proper disposal.
Keep drained oil filters in a closed leak-proof container or drum.
Transfer the fuel from the delivery tank trucks to the fuel storage tank over
impervious, contained areas and ensure that appropriate overflow protection is
used. Alternatively, cover nearby storm drains during the filling process and use
drip pans under all hose connections.
Supplemental BMPs
Use absorbent materials inor around catch basin inlets on the property to filter oily
runoff. Properly dispose of all gas and oil-contaminated absorbents
A catch basin inserts configured for oil removal may remove some of the pollutants
in runoff. The oil-absorbent filter media must be able to retain absorbed oil during
future storm events. Replace the filter media if the absorption capacity has been
surpassed. See the for more information
regarding which filter media provide acceptable oil retention.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-30: Marine Activities
o
A-47: Older Stationary Fueling Operations
o
A-48: Mobile Fueling of Vehicles and Heavy Equipment
o
, Chapter 5: Information Sheets
Catch Basin Insert
o
Containment
o
Covering
o
Oil/Water Separators
o
Spill Response and Clean-up Plan
o
–477–
kingcounty.gov/stormwater.
52
A-18:Vehicle and Equipment Repair and Maintenance
The following best management practices (BMPs) apply to vehicle and equipment repair
and maintenance.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Inspect all incoming vehicles and equipment for leaks and use drip pans or
absorbent material if necessary, while waiting for service.
Clean up any spilled fluids immediately. The collected material and absorbents must
be disposed of, reused, or recycled properly.
Cover, contain, and label waste oil, antifreeze, and other fluids.
Store batteries upright in a secure, contained, covered location (not outside on the
ground). Check to ensure batteries are not damaged or leaking. Keep battery acid-
neutralizing materials, such as baking soda, available near the storage area.
Regular work at stationary locations must be done indoors or in a covered area
using a tarp or drip pans beneath the vehicle or equipment to capture all spills and
drips.
Ensure that employees are familiar with the site’s spill response and cleanup plans
and are trained in the proper handling, storage, and disposal of all fluids.
Store and maintain appropriate spill cleanup materials in an easily accessible
location.
Required Routine Maintenance
Inspect parking and outside storage areas daily for leaks and drips.
Sweep paved work areas as needed. Soak up vehicle fluids with rags or other
absorbent material immediately. Never wash paved areas to the stormwater
drainage system or the street.
Supplemental BMPs
Absorbent material such as pillows or booms can be used around storm drains or in
catch basins to absorb oil and other substances.
A catch basin insert may be necessary. Catch basin inserts require frequent
maintenance to be effective.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
53
A-2: Outdoor Storage of Liquid Materials in Stationary Tanks
o
A-3: Storage of Liquid Materials in Portable Containers
o
A-11: Cleaning or Washing of Tools and Equipment
o
A-13: Vehicle Washing and Steam Cleaning
o
, Chapter 5: Information Sheets
Catch Basin Inserts
o
Containment
o
Covering
o
Disposal
o
Contact King County Local Hazardous Waste Management Program at 206-296-
4692 or visit www.hazwastehelp.org for information on the proper disposal and
recycling of vehicle fluids, filters, batteries and used absorbent material.
–477–
kingcounty.gov/stormwater.
54
A-19:Concrete and Asphalt Production and Recycling
The following best management practices (BMPs) apply to permanent production sites as
well as batch plants.
Mobile concrete pouring and asphalt applications are covered under activity sheet A-20:
Concrete and Asphalt Application.
This does not cover concrete production at mining or sand and gravel sites covered by a
King County Clearing and Grading Permit or National Pollutant Discharge Elimination
System (NPDES) Sand and Gravel Permit issued by the Washington State Department of
Ecology.
tants.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Discharge all process water generated from production, pouring, crushing and
equipment cleaning activities to a sump, process water recycling system, or sanitary
sewer system. Never wash contaminated water to the stormwater drainage system.
Discharge to the sanitary sewer system requires approval from the local sewer
district/agency.
Contain the production and pouring area to prevent pollutants from being washed
to the stormwater drainage system.
Required Routine Maintenance
Vacuum paved areas as necessary to prevent dust and particle mobilization. Collect
loose chunks of aggregate and raw material particles for recycling or proper
disposal. Do not hose down the area to the stormwater drainage system.
Dust suppression water may not be discharged to the stormwater drainage system.
Supplemental BMPs
A catch basin insert may be necessary. Catch basin inserts require frequent
maintenance to be effective.
Pave the mixing, production, and/or pouring area(s) with a slope that drains to a
central collection area.
Stormwater coming into contact with concrete crushing operations must be
collected and discharged to an approved discharge location.
55
When pH levels in stormwater rise above 8.5, the pH must be adjusted to the
acceptable range of 6.5 to 8.5. Refer to the
Manual, Appendix D for information on pH adjustment.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-11: Cleaning or Washing of Tools and Equipment
o
A-20: Concrete and Asphalt Application
o
A-31: Parking Lots, Driveways and Outside Storage Areas
o
, Chapter 5: Information Sheets
Catch Basin Inserts
o
Containment
o
Disposal
o
6–477–
kingcounty.gov/stormwater.
56
A-20:Concrete and Asphalt Application
The following best management practices (BMPs) apply to sites where asphalt is applied or
small amounts of concrete that is hand mixed on site. The application of premixed concrete
must follow the standards in the .
lutants.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Use drip pans, ground cloths, heavy cardboard, or plywood wherever concrete,
asphalt, asphalt emulsion and drips are likely to spill, such as beneath discharge
points from equipment.
Cover and contain all nearby storm drains at the beginning of the workday. Drain
covers and other containment devices are commercially available to keep runoff out
of the storm drainage system. All solids collected must be disposed of properly at
the end of the workday (or more frequently) prior to removing the containment or
cover device(s).
Contain and collect the slurry from exposed aggregate washing. Never allow the
slurry to get into a storm drain, ditch, roadway shoulder or gutter. Use a catch basin
cover, inlet protection or other containment device, such as a hand-dug, lined sump
to direct and contain slurry. All collected runoff must be disposed of properly.
Do not discharge concrete, slurry, or rinse water into gutters, storm drains, or
drainage ditches or onto the paved surface of a roadway or driveway.
Designate an area onsite where hand tools will be cleaned and the water collected
for disposal. Commercial products and services are also available for concrete,
slurry, and rinse water containment and disposal.
Do not use diesel fuel for cleaning or prepping asphalt tools and equipment.
Required Routine Maintenance
Sweep the pouring area at the end of the job or more frequently if needed. Collect
loose aggregate chunks and dust. Do not hose down the area to the stormwater
drainage system.
Supplemental BMPs
A catch basin insert may be necessary for sediment removal. Catch basin inserts
require frequent maintenance to be effective.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
57
A-11: Cleaning or Washing of Tools and Equipment
o
A-19: Concrete and Asphalt Production and Recycling
o
, Chapter 5: Information Sheets
Catch Basin Insert
o
Containment
o
Covering
o
Disposal
o
Appendix D – Concrete Handling
o
Appendix D – Concrete Washout Area
o
–477–
kingcounty.gov/stormwater.
58
A-21:Manufacturing and Post-Processing of Metal Products
The following best management practices (BMPs) apply tomills, foundries, and fabricators
that manufacture and/or post-process metal products at stationary sites. Painting,
finishing, and coating of metal products are covered under activity sheet A-22: Painting,
Finishing and Coating of Vehicles, Products and Equipment.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Keep metal fragments and debris (e.g., grindings, cuttings, dust, shavings) from
coming into contact with stormwater. Coverthe work area or perform the work
indoors.
Discharge process wastewater to a sanitary sewer, holding tank, or process
treatment system. Do not discharge to the stormwater drainage system.
Cover galvanized metal product storage and processing areas; or capture, treat, and
properly dispose of stormwater coming into contact.
Required Routine Maintenance BMPs
Sweep the work and pouring area at least daily to collect metal fragments and
debris and prevent stormwater contamination. Do not hose down the area tothe
stormwater drainage system.
Supplemental BMPs
Install catch basin inserts to collect excess sediment and debris, if necessary. Inspect
and maintain catch basin inserts regularly to ensure they are working correctly.
Install collection system to capture fragments and debris.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-9: Storage of Scrap and Recycling Materials (Including Auto Recycling
o
Facilities)
A-22: Painting, Finishing and Coating of Vehicles, Products and Equipment
o
, Chapter 5: Information Sheets
Catch Basin Insert
o
Covering
o
Disposal
o
59
–477–
kingcounty.gov/stormwater.
60
A-22:Painting, Finishing, and Coating of Vehicles, Products
and Equipment
The following best management practices (BMPs) apply to the painting, finishing, and
coating of vehicles, products, and equipment and includes preparation work such as
sanding and blasting.
Best management practices for painting buildings are covered in activity sheet A-29:
Building Repair, Remodeling and Construction. Painting and other work on vessels is
covered in activity sheet A-30: Marine Activities.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Painting must be done in an enclosed work area and meet the standards of the Puget
Sound Clean Air Agency.
Vehicle painting must be done in paint booths approved and permitted by Puget
Sound Clean Air Agency.
Properly dispose of paint booth filters as required under dangerous and hazardous
waste regulations.
Collect dust and debris from sanding operations using vacuum sanders, ground
cloths or similar methods. Do not hose down the area to the stormwater drainage
system.
Use ground cloths and/or drip pans in outdoor locations where paints, finishes, and
other liquid materials are mixed and/or applied.
Required Routine Maintenance
Store and maintain appropriate spill cleanup materials in a location known to all
employees.
Train all employees on the site’s spill control plan and/or proper spill cleanup
procedures.
Sweep the area at the end of each day at a minimum. Do not hose down the area to
the storm drainage system.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-29: Building Repair, Remodeling and Construction
o
61
A-30: Marine Activities
o
A-39: Roof Vents and Fugitive Emissions
o
Puget Sound Clean Air Agency, 206-343-8800
Contact King County Local Hazardous Waste Management Program at 206-296-
4692 or visit www.hazwastehelp.org for information on the proper disposal of
hazardous waste.
–477–
kingcounty.gov/stormwater.
62
A-23:Wood Treatment and Preserving
The following best management practices (BMPs) apply to wood treatment performed
outdoors including storage of freshly treated wood materials outdoors. It includes
permanent sites as well as temporary sites.
Large-scale commercial operations are required to have a stormwater National Pollutant
Discharge Elimination System (NPDES) permit from the Washington State Department of
Ecology.
o
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Collect drips and spills using ground cloths or drip pans.
Store portable containers of wood preservative compounds indoors or in a covered
location with appropriate secondary containment when not in use.
Hold dipped lumber over dip tanks until dripping ceases (if applicable).
Store treated lumber in a covered and paved area until fully dry.
Cover and contain the storage area to prevent stormwater from running into the
covered area.
Required Routine Maintenance
Cover outdoor dip tanks when not in use.
Additional Information
al,Chapter 3: Commercial and Multifamily
BMPs
A-3:Storage of Liquid Materials in Portable Containers
o
, Chapter 5: Information Sheets
Containment
o
Covering
o
Spill Response and Cleanup Plan
o
–477–
kingcounty.gov/stormwater.
63
A-24:Commercial Composting
The following best management practices (BMPs) apply to commercial receiving and
composting wastes.
In addition to other King County requirements, all commercial composting operations must
comply with Public Health-Seattle and King County requirements. Commercial composting
operations require a National Pollutant Discharge Elimination System (NPDES) permit
and/or a State Waste Discharge permit from the Washington State Department of Ecology.
Potential pollutants can include but are not limited to fecal coliform bacteria, metals,
nutrients, oxygen demanding substances, PCBs, sediment, and other pollutants.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
All composting facilities shall obtain the appropriate state and local permits. Contact
Public Health – Seattle and King County for more information.
Screen incoming waste for dangerous materials and solid waste. These materials
may not be accepted for composting and must be properly disposed of.
Locate composting areas on impervious surfaces.
Drain all leachate from composting operations to the sanitary sewer, holding tank,
or on-site treatment system. Leachate may not go to the stormwater drainage
system or groundwater.
Collect the leachate with a dike or berm, or with intercepting drains placed on the
down slope side of the compost area.
Direct outside runoff away from the composting areas.
Collect runoff from uncovered finished compost and blending areas and discharge to
the sanitary sewer. If that is not feasible, then discharge to surface or ground waters
according to the condition of a Washington State Industrial Stormwater General or
Individual permit or a State Waste Discharge Permit.
See Washington Administrative Code 173-350-220 (Composting Facilities) for
additional requirements.
Required Routine Maintenance
Clean up debris from yard areas regularly to prevent stormwater contamination.
Supplemental BMPs
Install catch basin inserts to collect excess sediment and debris if necessary. Inspect
and maintain catch basin inserts regularly to ensure they are working correctly.
Cover compost storage areas.
64
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-4: Outdoor Storage of Soil, Sand and Other Erodible Materials
o
, Chapter 5: Information Sheets
Catch Basin Inserts
o
Containment
o
Disposal
o
Contact Public Health-Seattle and King County at 206-263-9566
Washington Administrative Code 173-350-220 (Composting Facilities)
Washington State Department of Ecology’s
https://apps.ecology.wa.gov/publications/documents/1107005.pdf
–477–
kingcounty.gov/stormwater.
65
A-25:Chemical Applications – Other Than Landscaping
The following best management practices (BMPs) apply to the use of pesticides, herbicides
or other chemicals for such purposes as removing or preventing future growth of rooftop
moss, killing nuisance rodents, and using fungicides to preserve patio decks.
Application of pesticides for landscaping is covered under activity sheet A-5: Storage and
Use of Pesticides and Fertilizers. Best management practices for washing of roofs are in
activity sheet A-15: Washing of Buildings, Rooftops and Other Large Surfaces.
Businesses/agencies engaged in this activity must comply with Public Health-Seattle and
King County structural pesticide applicator regulations. The BMPs listed here are intended
to complement other regulations. Washington pesticide law requires most businesses that
commercially apply pesticides to the property of another to be licensed as a Commercial
Applicator from the Washington State Department of Agriculture.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Avoid excessive application of chemicals. Follow manufacturers’ application
guidelines and label directions.
Never apply pesticides or other chemicals in the rain.
Clean up any spilled chemicals immediately. Do not hose down chemicals to the
stormwater drainage system.
Do not spray pesticides within 100 feet of open waters, including wetlands, ponds,
and streams, unless approved by local jurisdiction.
Train employees on proper application and disposal practices
Supplemental BMPs
Integrated pest management (IPM), a comprehensive approach to the use of
pesticides which minimizes application and stresses selection of proper products
and tailored application rates, is the most effective BMP measure that can be taken.
IPM is applicable to businesses that frequently apply pesticides.
Use manual pest control strategies such as physically scraping moss from rooftops,
high-pressure sprayers to remove moss, and rodent traps.
Select the least toxic chemical application that can accomplish the job.
Additional Information
66
, Chapter 3: Commercial and Multifamily
BMPs
A-2: Outdoor Storage of Liquid Materials in Stationary Tanks
o
A-3: Storage of Liquid Materials in Portable Containers
o
A-5: Storage and Use of Pesticides and Fertilizers
o
A-15: Washing of Buildings, Rooftops, and Other Large Surfaces
o
, Chapter 5: Information Sheets
Containment
o
Covering
o
Disposal
o
–477–
kingcounty.gov/stormwater.
67
A-26:Landscaping Activities, Vegetation Management, and
Irrigation
The following best management practices (BMPs) apply to landscaping, vegetation
management and irrigation activities which include grading, soil transfer, vegetation
planning, and vegetation removal. For storage and use of pesticides and fertilizers see
activity sheet A-5: Storage and Use of Pesticides and Fertilizers.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs – Landscaping and Vegetation Management
Do not dispose of collected vegetation into surface waters or stormwater drainage
systems.
Do not blow vegetation or other debris into the stormwater drainage system,
sidewalks, or street. Dispose of collected vegetation by recycling or composting.
Use mulch or other erosion control measures when soils are exposed for more than
one week during the dry season (May 1 to September 30) or two days during the
rainy season (October 1 to April 30).
Ensure sprinkler systems do not “overspray” vegetated areas resulting in the excess
water discharging into the stormwater drainage system.
Ensure that plants selected for planting are not on the noxious weed list. Remove,
bag, and dispose of class A and B noxious weeds in the garbage immediately. Make
reasonable attempts to remove and dispose of class C noxious weeds. Do not
compost noxious weeds as it may lead to spreading through seed or fragment if the
composting process is not hot enough.
New and expanding golf courses must have a Golf Course Management Plan as
described in addressed in the King County Golf Course BMP Manual
Required BMPs - Irrigation
Ensure sprinkler systems do not overspray vegetated areas resulting in runoff
discharging into surface waters or stormwater drainage systems. Adjust watering
times and schedules to ensure that the appropriate amount of water is being used to
minimize runoff. Consider factors such as soil structure, grade, time of year, and
type of plant material in determining the proper amounts of water for a specific
area.
Inspect irrigated areas regularly for signs of erosion and/or discharge.
68
Do not irrigate plants during or immediately after fertilizer application. The longer
the period between fertilizer application and irrigation, the less fertilizer runoff
occurs.
Do not irrigate plants during or immediately after pesticide application (unless the
pesticide label directs such timing).
Reduce frequency and/or intensity of watering as appropriate for the wet season
(October 1 to April 30).
Supplemental BMPs -Landscaping and Vegetation Management
Select the right plants for the planting location based on proposed use, available
maintenance, soil conditions, sun exposure, water availability, height, sight factors,
and space available.
Use native plants in landscaping. Native plants do not require extensive fertilizer or
pesticide applications.
Install engineered soil/landscape systems to improve the infiltration and regulation
of stormwater in landscaped areas.
Use at least an eight-inch "topsoil" layer with at least 8 percent organic matter to
provide a sufficient vegetation-growing medium.
Organic matter is the least water-soluble form of nutrients that can be added
o
to the soil. Composted organic matter generally releases only between 2 and
10 percent of its total nitrogen annually, and this release corresponds closely
to the plant growth cycle. Return natural plant debris and mulch to the soil,
to continue recycling nutrients indefinitely.
Select the appropriate turfgrass mixture for the climate and soil type.
Certain tall fescues and rye grasses resist insect attack because the symbiotic
o
endophytic fungi found naturally in their tissues repel or kill common leaf
and stem-eating lawn insects.
The fungus causes no known adverse effects to the host plant or to
humans.
Tall fescues and rye grass do not repel root-feeding lawn pests such as
Crane Fly larvae.
Tall fescues and rye grass are toxic to ruminants such as cattle and
sheep.
Endophytic grasses are commercially available; use them in areas such as
o
parks or golf courses where grazing does not occur.
Local agricultural or gardening resources such as Washington State
o
University Extension office can offer advice on which types of grass are best
suited to the area and soil type.
Adjusting the soil properties of the subject site can assist in selection of desired
plant species. Consult a soil restoration specialist for site-specific conditions.
69
Remove weeds/vegetation in stormwater ditches by hand or other mechanical
means and only use chemicals as a last resort. If herbicides are used, refer to activity
sheet A-5: Storage and Use of Pesticides and Fertilizers for required BMPs.
Conduct mulch-mowing whenever practicable.
Till a topsoil mix or composted organic material into the soil to create a well-mixed
transition layer that encourages deeper root systems and drought-resistant plants.
Apply an annual topdressing application of 3/8” compost. Amending existing
landscapes and turf systems by increasing the percent organic matter and depth of
topsoil can:
Substantially improve the permeability of the soil.
o
Increase the disease and drought resistance of the vegetation.
o
Reduces the demand for fertilizers and pesticides.
o
Disinfect gardening tools after pruning diseased plants to prevent the spread of
disease.
Prune trees and shrubs in a manner appropriate for each species.
If specific plants have a high mortality rate, assess the cause, and replace with
another more appropriate species.
When working around and below mature trees, follow the most current American
National Standards Institute (ANSI) ANSI A300 standards,
http://www.tcia.org/TCIA/BUSINESS/ANSI_A300_Standards_/TCIA/BUSINESS/A3
00_Standards/A300_Standards.aspx?hkey=202ff566-4364-4686-b7c1-
2a365af59669, and International Society of Arboriculture BMPs to the extent
practicable (e.g., take care to minimize any damage to tree roots and avoid
compaction of soil).
Monitor tree support systems (stakes, guys, etc.).
Repair and adjust as needed to provide support and prevent tree damage.
o
Remove tree supports after one growing season or maximum of 1 year.
o
Backfill stake holes after removal.
o
When continued, regular pruning (more than one time during the growing season)
is required to maintain visual sight lines for safety or clearance along a walk or
drive, consider relocating the plant to a more appropriate location.
Re-seed bare turf areas until the vegetation fully covers the ground surface.
Watch for and respond to new occurrences of especially aggressive weeds such as
Himalayan blackberry, Japanese knotweed, morning glory, English ivy, and reed
canary grass to avoid invasions.
Aerate lawns regularly in areas of heavy use where the soil tends to become
compacted. Con-duct aeration while the grasses in the lawn are growing most
vigorously. Remove layers of thatch greater than ¾-inch deep.
70
Set the mowing height at the highest acceptable level and mow at times and
intervals designed to minimize stress on the turf. Generally mowing only 1/3 of the
grass blade height will prevent stressing the turf.
Mowing is a stress-creating activity for turfgrass.
o
Grass decreases its productivity when mowed too short and there is less
o
growth of roots and rhizomes. The turf becomes less tolerant of
environmental stresses, more dis-ease prone and more reliant on outside
means such as pesticides, fertilizers, and irrigation to remain healthy.
Supplemental BMPs - Irrigation
Repair broken or leaking sprinkler nozzles as soon as possible.
Water deeply, but infrequently, so that the top 6 to 12 inches of the root zone is
moist. Appropriately irrigate lawns based on the species planted, the available
water holding capacity of the soil, and the efficiency of the irrigation system.
The depth from which a plant normally extracts water depends on the
o
rooting depth of the plant. Appropriately irrigated lawn grasses normally
root in the top 6 to 12 inches of soil; lawns irrigated on a daily basis often
root only in the top 1 inch of soil.
Irrigate with the minimum amount of water needed. Never water at rates that
exceed the infiltration rate of the soil.
Maintain all irrigation systems so that irrigation water is applied evenly and where
it is needed.
Place sprinkler systems appropriately so that water is not being sprayed on
impervious surfaces instead of vegetation.
Place irrigation systems to ensure that plants receive water where they need it. For
example, do not place irrigation systems downgradient of plant’s root zones on
hillsides.
Use soaker hoses or spot water with a shower type wand when an irrigation system
is not present.
Pulse water to enhance soil absorption, when feasible.
o
Pre-moisten soil to break surface tension of dry or hydrophobic soils/mulch,
o
followed by several more passes. With this method, each pass increases soil
absorption and allows more water to infiltrate prior to runoff.
Add a tree bag or slow-release watering device (e.g., bucket with a perforated
bottom) for watering newly installed trees when irrigation system is not present.
Identify trigger mechanisms for drought-stress (e.g., leaf wilt, leaf senescence, etc.)
of different species and water immediately after initial signs of stress appear.
Water during drought conditions or more often if necessary, to maintain plant
cover.
Adjust irrigation frequency / intensity as appropriate after plant establishment.
Annually inspect irrigation systems to ensure:
71
That there are no blockages of sprayer nozzles.
o
Sprayer nozzles are rotating as appropriate.
o
Sprayer systems are still aligned with the plant locations and root zones.
o
Consult with the local water utility, King Conservation District, or Cooperative
Extension office to help determine optimum irrigation practices.
Do not use chemigation and fertigation in irrigation systems. This will help avoid
over application of pesticides and fertilizers.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-5: Storage and Use of Pesticides and Fertilizers
o
Natural Yard Care Program:
http://your.kingcounty.gov/solidwaste/naturalyardcare/watering.asp
The King County Devel
Operation https://your.kingcounty.gov/dnrp/library/water-and-
land/stormwater/stormwater-pollution-prevention-
manual/Best%20Manangement%20Practices%20for%20Golf%20Course.pdf
The King County Noxious Weed List can be found at
https://www.kingcounty.gov/services/environment/animals-and-plants/noxious-
weeds/laws.aspx. Additional information on the Washington State Noxious Weed
List can be found at https://www.nwcb.wa.gov/printable-noxious-weed-list
The King County Noxious Weed Control Program provides best management
practices for the removal of typical noxious weeds such as blackberry and purple
loosestrife. Call 206-296-0290 or see:
http://www.kingcounty.gov/environment/animalsandplants/noxious-
weeds/weed-control-practices.aspx for more information
–477–
kingcounty.gov/stormwater.
72
A-27:Clearing and Grading of Land for Small Construction
Projects
Best management practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of stormwater,
you will be required to take additional measures.
Required BMPs
King County Permitting coordinates the clearing, grading, and erosion control
requirements on individual sites. Contact Permitting prior to clearing, grading, and
preparation activities for construction-sites greater than 2,000 square feet.
Even if your site does not require a permit, erosion control measures are still
required to prevent turbid water from entering stormwater drainage systems or
surface waters.
Follow the procedures for construction-site erosion and sediment control outlined
in the :
Appendix C: Small Project Drainage Requirements
o
Appendix D: Erosion and Sediment Control Standards
o
Additional Information
–477–
kingcounty.gov/stormwater.
73
A-28:Demolition of Buildings
The following best management practices (BMPs) applyto the removal of existing
buildings and other structures by controlled explosions, wrecking balls or other methods,
and subsequent clearing of the rubble.
otherpollutants.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Train employees about the need to control site activities to prevent stormwater
pollution, and train them in spill cleanup procedures
Protect the stormwater drainage system from dirty runoff and loose particles by
placing catch basin covers, or a similarly effective containment device, on all nearby
storm drains.
Place the covers (or devices) on the storm drains at the beginning of the
o
workday.
Inspect daily and maintain the covers (or devices) to ensure they are
o
working correctly.
At the end of each workday, collect and properly dispose of the accumulated
o
materials before removing the covers (or devices).
Use dikes, berms, or other methods to protect natural drainage paths from
o
dirty runoff if storm drains are not present.
Remove all covers and devices when the job is completed.
Cover waste container and dumpsters and ensure they are not leaking.
Sweep surrounding streets, sidewalks, driveways, and other paved surfaces as
needed and at the end of the workday to collect loose debris and garbage. Properly
dispose of collected debris and garbage. Do not hose down these areas to the
stormwater drainage system.
Handle and dispose of all waste materials and demolition debris in a manner that
does not cause contamination of stormwater.
Control windblown dust and fine materials by applying water or dust suppression
products, avoiding excessive application to prevent runoff. Do not use oils for dust
control.
Supplemental BMPs
74
Construct a screen to prevent stray building materials and dust from escaping the
area during demolition. Size and orient the screen to capture windblown materials
and contain them onsite.
When feasible, schedule demolition to take place at a dry time of the year to prevent
stormwater runoff from the demolition-site.
Additional Information
, Chapter 5: Information Sheets
Catch Basin Insert
o
, Appendix D: Construction Stormwater
Pollution Prevention Standards
–477–
kingcounty.gov/stormwater.
75
A-29:Building Repair, Remodeling and Construction
The following best management practices (BMPs) apply to the construction of buildings
and other structures, remodeling of existing buildings, houses and other structures, and
general exterior building repair work.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Train employees about the need to prevent stormwater pollution.
Keep spill cleanup materials in a common location onsite at all times. Train
employees on spill prevention and clean up measures.
Identify, remove, and properly dispose of hazardous substances from the building
before beginning repairing or remodeling activities that could expose them to
stormwater. Such substances could include PCBs, asbestos, lead paint, mercury
switches, and electronic waste.
Use a catch basin cover, filter fabric, or other runoff control mechanism if dust, grit,
wash water, or other pollutants may escape the work area.
Place the coveror containment device over the catch basin at the beginning
o
of the workday.
Collect and properly dispose of accumulated dirty runoff and solids before
o
removing the cover or device at the end of each workday.
Check runoff control mechanisms and replace as necessary.
o
Do not dump any substance, wash water or liquid waste on the pavement, ground,
or into the stormwater drainage system
Use drop cloths when painting, scraping, and sandblasting and properly dispose of
collected material daily. Use drip pans in areas where drips are likely to occur if the
area cannot be protected with a drop cloth.
Cleaning paint brushes and tools:
Clean paint brushes and tools covered with water-based paints in sinks
o
connected to sanitary sewers or in portable containers that can be dumped
into a sanitary sewer.
Brushes and tools covered with non-water-based paints, finishes, or other
o
materials must be cleaned in a manner that enables collection of used
solvents (e.g., paint thinner, turpentine, etc.) for recycling or proper disposal.
Solvents may not be disposed of to the sanitary sewer.
Never dispose of any wash water to a storm drain.
o
76
Refer to activity sheet A-15: Washing of Buildings, Rooftops, and Other Large
Surfaces for best management practices associated with pressure washing
buildings.
Control windblown dust and fine materials by applying water or dust suppression
products, avoiding excessive application to prevent runoff. Do not use oils for dust
control.
Cover trash bins and dumpsters and ensure they are not leaking.
Follow Appendix D of the , “Erosion and
Sediment Control Measures” for dewatering activities.
Required Routine (Daily) Maintenance
Sweep paved areas to collect loose particles for proper disposal. Consider using
filtered vacuuming to collect waste that may be hard to sweep, such as dust on a
drop cloth.
Wipe up spills with rags or other absorbent material immediately. Do not hose
down the area to the stormwater drainage system.
Store materials, such as solvents, indoors or under cover and secures so that
unauthorized personnel will not have access to them.
Supplemental BMPs
Recycle or reuse leftover materials.
Set up temporary cover in wet weather conditions.
Install temporary wheel wash facilities if track out occurs.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-11: Cleaning or Washing of Tools and Equipment
o
A-15: Washing of Buildings, Rooftops, and Other Large Surfaces
o
A-20: Concrete and Asphalt Application
o
A-41: Wheel Wash and Tire Bath Track Out Control
o
, Chapter 5: Information Sheets
Catch Basin Insert
o
, Appendix D: Construction Stormwater
Pollution Prevention Standards
–477–
kingcounty.gov/stormwater.
77
A-30:Marine Activities
The following best management practices (BMPs) apply to businesses that operate in or
over the marine environment. Marine activities include:
operations not covered by a National Pollutant Discharge Elimination System
(NPDES) permit from the Washington State Department of Ecology (e.g., boatyard
general permit);
transferring fuels from a fueling station to vehicles or equipment in or over surface
waters; and
washing docks, wharves, piers, floats, and boat ramps.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of surface water and stormwater, you will be
required to take additional measures.
Ship/Boat/Watercraft Building, Maintenance and Repair
Required BMPs
Move maintenance and repair activities onshore, if possible.
Enclose blasting and spray-painting activities by deploying tarps to prevent dust
and overspray from escaping. Use sanders that have dust containment bags. Collect
drips and spills using drop cloths or drip pans.
Collect bilge and ballast water that has an oily sheen on the surface. Properly
dispose of it rather than dumping it in surface waters or on land.
Perform paint and solvent mixing, fuel mixing, and similar handling of liquids on
land to avoid spilling into the water. Clean up spills immediately. Do not wash spills
to the stormwater drainage system or surface waters.
Collect and properly dispose of wash water from washing painted boathulls. Never
dispose of wash water containing soap or other chemicals to the stormwater
drainage system or surface waters.
Cover boat construction and structural repair activities.
Place a tarp underneath the work area on boats or piers to collect drips, spills, paint
chips, and loose solids when work is performed over water.
Do not use soaps or detergents of any kind to wash the topsides or hulls of boats
where the wash water will enter surface waters.
Required Routine Maintenance
Store and maintain appropriate spill cleanup materials in a readily accessible
location.
Have a current spill control plan and train all employees on proper spill cleanup
procedures.
78
Sweep maintenance yard areas, piers, wharves, and boat ramps to collect
sandblasting material, paint chips, oils, and other loose debris. Properly dispose of
these collected materials. Do not hose down the area to the water or to a storm
drain.
Additional Information
Stormw, Chapter 3: Commercial and Multifamily
BMPs
A-3: Storage of Liquid Materials in Portable Containers
o
A-11: Cleaning or Washing of Tools and Equipment
o
A-18: Vehicle and Equipment Repair and Maintenance
o
, Chapter 5: Information Sheets
Disposal
o
Washington State Department of Ecology’s W
https://fortress.wa.gov/ecy/publications/summarypages/95056.html
In-Water and Over-Water Fueling Operations
Required BMPs
Facilities that load or unload petroleum products must comply with U.S. Coast
Guard requirements. Refer to specifications in Coast Guard Requirements for Marine
Transfer of Petroleum Products.
Refer to activity sheets A-17: Stationary Fueling Operations and A-47: Older
Stationary Fueling Operations for applicable best management practices.
Required BMPs – Training and Fuel Dock Supervision
Have a trained employee supervise the fuel dock during fueling activities.
Do not allow self-service on a marina dock without some means of controlling the
dock activity. This can be done via camera, intercom, and shutoff abilities in the
office.
Required BMPs – Fueling Dock Setup, Maintenance, and Inspection
Install personal watercraft floats at fuel docks to stabilize personal watercraft/jet
skis while refueling.
Use automatic shut-off nozzles and promote the use of “whistles” and fuel/air
separators on air vents or tank stems of inboard fuel tanks to reduce the amount of
fuel spilled into receiving waters during fueling of boats.
Have spill containment booms, pads, and absorbents easily accessible and clearly
marked.
Post a spill response and cleanup plan where employees can easily see it and keep
contact information current.
79
Post readable refueling directions, BMPs, and emergency protocols at the fueling
station.
Post a sign with emergency spill reporting phone numbers clearly visible. Marinas
on land leased from the Washington Department of Natural Resources (DNR) are
required to post the “Spills Aren’t Slick” signage.
Display “No Smoking” signs on fuel docks.
Create a regular inspection, maintenance, and replacement schedule for fuel hoses,
pipes, tanks, and spill cleanup materials. Have staff walk the dock fuel lines from
dispenser to tank to look for signs of leakage at joints and determine hose condition
from end to end.
Required BMPs – Fueling Practices
Discourage operators from “topping off”. Fuel expands and can slosh out of the vent
when temperatures rise or waters become choppy.
When handing over the nozzle, wrap an absorbent pad around the nozzle end or
plug inside the nozzle end to prevent fuel in the nozzle from spilling.
Have the boat operator place an absorbent pad or suction cup bottle under the
vent(s) to capture fuel spurts from the vent.
Never block open the fuel nozzle trigger and always disable hands-free clips to
ensure the boater remains with the nozzle to prevent overfilling. Hands-free clips
are not allowed in Washington, per WAC 296-24-33015.
Always keep the nozzle tip pointing up and hang the nozzle vertically when not in
use.
During fueling operations, visually monitor the liquid level indicator to prevent the
tank from being overfilled.
The maximum amount of product received must not exceed 95 percent capacity of
the receiving tank.
Required BMPs – Spill Cleanup
Train all employees on required spill response methods and procedures.
Manage petroleum-contaminated booms, pads, and absorbents in a designated
collection container and properly dispose of these materials.
Do not use soaps or dispersants in the event of a spill. Use absorbent materials
instead.
See activity sheets A-2: Outdoor Storage of Liquid Materials in Stationary Tanks and
A-3: Storage of Liquid Materials in Portable Containers for additional BMPs.
Required BMPs – Fueling by Portable Container
Have boats fuel on shore or at a fuel dock rather than transport fuel from an upland
facility to the boats. Only use hand-held fueling containers or “jerry cans” when
necessary or when shore or dock fueling is not practical.
80
Always refill portable fuel containers on the pavement or dock to ensure a good
electricalground. While the deck of the boat may seem stable, static electricity can
build up and cause a spark.
On the dock, put an absorbent pad under the container and wrap an absorbent pad
around the fuel fill — this can easily be done by putting a hole in the pad.
Ensure the nozzle stays in contact with the tank opening.
When transferring fuel from a portable can, use a fuel siphon with a shut-off feature.
If a siphon is not available, a nozzle/spout with a shut off is a good alternative.
Since fueling boats with a portable container can take time, make sure the container
is comfortable to carry, hold, and balance.
Use a high flow funnel. Funnels can help prevent spills by making a larger opening
for fueling.
Place a plug of absorbent pad or paper towel in the nozzle when not in use to
capture any extra drops that accumulate.
Fuel slowly, pour deliberately and watch the container (especially the nozzle
mechanism) for signs of wear.
Store portable fuel tanks out of direct sunlight and keep in a cool, dry place to
minimize condensation.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-2: Outdoor Storage of Liquid Materials in Stationary Tanks
o
A-3: Storage of Liquid Materials in Portable Containers
o
A-17: Stationary Fueling Operations
o
A-47: Older Stationary Fueling Operations
o
, Chapter 5: Information Sheets
Disposal
o
Spill Response and Cleanup Plan
o
Dock Washing
Required BMPs – Surface Preparation and Spot Cleaning
Use dry methods and equipment (scraping, sweeping, vacuuming) to remove debris,
bird feces and other contaminants prior to cleaning with water to prevent these
pollutants from entering surface water. This will minimize the need for chemical
cleaners. Dispose of debris from the dock as solid waste.
During cleaning activities, if debris, substances, or wash water have the potential to
enter surface waters through drains, temporarily block the drains prior to cleaning
activities.
81
Hose down the area if necessary and to the extent practicable, collect wash water
and dispose of it properly.
If the dock is paved, the landward area is vegetated, and no soaps or
o
detergents are used, then the wash water does not have to be collected if the
water can soak into the ground without discharging to surface waters or the
storm drainage system. However, the wash water does have to be filtered to
trap solid materials before entering vegetated areas.
If the dock and the landward area are both paved, then use a sump pump,
o
wet vacuum or similar device that enables collection of wash water and
associated solids so they can be disposed of in a sink or toilet for treatment at
your local sewage treatment plant. On-site septic systems should not receive
wash water containing harsh chemicals. The wash water must not go to
surface waters or storm drainage system.
Spot clean with water and a coarse cloth before using soaps or detergents or
washing down an area.
If a cleaner is needed for spot cleaning:
Mix it in a bucket and use it to scrub down only the areas that need extra
o
attention.
Try starting with vinegar and baking soda and move to other options as
o
needed. Spot clean using a rag if harsher cleaning products are needed.
Use a mild detergent or soap that is pH neutral. Avoid or minimize the use of
o
petroleum distillates, chlorinated solvents, and ammoniated cleaning agents.
Use degreasers or absorbent material to remove residual grease by hand and
o
do not allow this material to enter surface waters.
Keep cleaners in sealed containers and keep cleaner containers closed
o
securely when transporting between the shore and docks.
Properly dispose of wash water.
o
Minimize the scour impact of wash water to any exposed soil at the landward end(s)
of the dock or below the dock. Place a tarp over exposed soil, plant vegetation, or
put berms to contain eroded soil.
Required BMPs – Dock Washing and Disposal
During cleaning activities, if debris, substances, or wash water could enter surface
waters through drains, then temporarily block the drains and collect all of the wash
water.
To the extent practicable, collect any wash water generated from cleaning dock
areas, and dispose of it properly.
If the dock is paved, the landward area is vegetated and no soaps or
o
detergents are used, then the wash water does not have to be collected if the
water can soak into the ground without discharging to surface waters or the
storm drainage system. However, the wash water does have to be filtered to
trap solid materials before entering vegetated areas.
82
If the dock and the landward area are both paved, then use a sump pump,
o
wet vacuum or similar device that enables collection of wash water and
associated solids so they can be disposed of in a sink or toilet for treatment at
your local sewage treatment plant. On-site septic systems should not receive
wash water containing harsh chemicals. The wash water must not go to
surface waters or storm drainage system.
If pressure washing use only light pressure. Avoid using excessive pressure, which
may damage the dock or send flakes of paint and other material into the water. If the
surface is painted with lead or other heavy metal-bearing paint (such as chromium
or cadmium), use a commercial pressure washing service that will collect, test, and
properly dispose ofthe wash water.
Do not place any debris or substances resulting from cleaning activities in shoreline
areas, riparian areas, or on adjacent land where these substances may erode into
surface waters.
Where treated wood associated with the structure being washed are present, use
non-abrasive methods and tools that, to the maximum extent practicable, minimize
removal of the creosote or treated wood fibers when it removes marine growth
from creosote or any other treated wood.
Do not discharge removed marine growth to surface waters.
Do not discharge emulsifiers, dispersants, solvents, or other toxic deleterious
materials to surface waters or storm drainage systems.
Required BMPs – Goose Waste
If possible, pick up goose waste using shovels, brooms, rakes, power sweepers, and
trash cans. Properly dispose of goose waste in the garbage.
Do not blow, sweep, or wash goose waste into surface waters or storm drainage
systems.
Regularly clean goose waste from areas of chronic deposition.
Supplemental BMPs- Goose Waste
Do not feed wild geese or other waterfowl.
Change areas of chronic accumulation of goose waste from goose friendly to goose
resistant. Reduce lawn areas and increase the height of shoreline vegetation (tall
grass, shrubs) as geese are reluctant to walk through tall vegetation.
Geese’s favorite food is new shoots of grass. Let grass grow to six inches or taller.
Stop fertilizing and watering lawn in areas of geese accumulation to reduce the
palatability of the lawn.
Create a natural geese barrier of 20 to 100 feet of herbaceous vegetation at least 3
feet in height to discourage geese. A narrow, winding path through the plantings will
allow for beach access, while preventing geese from having a direct line of sight
through the planted area. Minimize open sight lines for geese to less than 30 feet.
Where space is limited, use one or two rows of shrub plantings combined with a
fence to construct a geese barrier. Fences should be at least 24 inches tall (3 feet
83
may be better), firmly constructed, and installed to prevent the geese from walking
around the ends. Lower openings should be no larger than 4 inches from the ground
to prevent goslings from walking under or through the fence.
Construct bank slopes steeper than 4:1 to discourage geese by preventing a clear
view of the bank top and potential predators. Or, separate the beach from the grass
with a few steepsteps, which makes the ascent too difficult for most geese.
Plant shrubs or trees near the water’s edge to limit takeoff and landing
opportunities.
Scare geese away when they are around. Geese often learn quickly to ignore scare
devices that are not a real physical danger. Vary the use, timing, and location of
tactics. Examples of harassment and scare tactics include dogs, monitor lizards,
eyespot balloons, flags and streamers, and scarecrows.
Canada geese are protected under federal and state law. A hunting license and open
season are required to hunt them. Where lethal control is necessary outside of
hunting seasons, it should be carried out only under permits issued by the U.S. Fish
and Wildlife Service.
Additional Information
, Chapter 5: Information Sheets
Controlling and Collecting Contaminated Runoff
o
Drainage Maintenance Contractors
o
Spill Response and Cleanup Plan
o
The Humane Society of the United States’
Maa
http://www.humanesociety.org/assets/pdfs/wild_neighbors/canada_goose_guide.p
df
–477–
kingcounty.gov/stormwater.
84
A-31:Parking Lots, Driveways and Outside Storage Areas
.
Best management practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of surface water
and stormwater, you will be required to take additional measures.
Required BMPs
Sweep areas as needed to collect dirt, waste, debris,and spilled material. Do not
hose down areas to the stormwater drainage system or surface waters.
Clean up vehicle and equipment fluid drips and spills immediately using absorbent
materials.
Place drip pans under leaking vehicles and equipment, including employee vehicles,
until the vehicle/equipment no longer leaks. Properly dispose of accumulated
leaked fluids.
Pressure wash water from paved areas must be collected and disposed of to the
sanitary sewer or hauled for offsite disposal, even if soaps, detergents, or cleaners
are not used. If the surface to be pressure washed is not utilized by automotive
equipment or machinery, see activity sheet A-15: Washing of Building, Rooftops and
Other Large Surfaces.
There are businesses that will clean parking lots and collect water for off-site
disposal. Never drain wash water to the stormwater drainage system.
Follow basic sediment controls as outlined in Appendix D (“Erosion and Sediment
Control Standards”) of the for gravel and
dirt lots. These types of parking lots may require additional BMPs to prevent
sediment-laden water from leaving your site.
Supplemental BMPs
Encourage employees to repair leaking personal vehicles.
Install catch basin inserts to collect excess sediment and oil, if necessary. Inspect
and maintain catch basin inserts regularly to ensure they are working correctly.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-3: Storage of Liquid Materials in Portable Containers
o
A-15: Washing of Buildings, Rooftops, and Other Large Surfaces
o
, Chapter 5: Information Sheets
Catch Basin Insert
o
Disposal
o
85
–477–
kingcounty.gov/stormwater.
86
A-32:Sidewalk Maintenance
Best management practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of surface water
and stormwater, you will be required to take additional measures.
Required BMPs
Sweep sidewalks as needed to collect loose dirt and debris rather than blowing or
pushing it into the street or gutter or hosing it down. Collected materials must be
disposed of as solid waste.
Clean individual stains instead of washing the entire sidewalk, if possible.
Collect wash water and dispose of into the sanitary sewer or take off-site for
appropriate disposal if soaps or other cleaners are used. If only water is used, then
install a catch basin insert or filter cloth in order to collect all solids and debris.
Use a minimum amount of sand or deicing salts and sweep up any remaining
granules when the snow and ice have melted.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-3: Storage of Liquid Materials in Portable Containers
o
A-15: Washing of Buildings, Rooftops, and Other Large Surfaces
o
A-31: Parking Lots, Driveways and Outside Storage Areas
o
, Chapter 5: Information Sheets
Containment
o
Disposal
o
Fo–477–
kingcounty.gov/stormwater.
87
A-33:Swimming Pool and Spa Cleaning and Maintenance
The following best management practices (BMPs) apply to pools, spas, hot tubs, and
fountains that use chemicals and/or that are heated.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required Operational BMPs
Clean the pool, spa, hot tub, or fountain regularly, maintain proper chlorine levels
and maintain water filtration and circulation. Doing so will limit the need to drain
the facility.
Manage pH and water hardness to reduce copper pipe corrosion that can stain the
facility and pollute receiving waters.
Before using copper algaecides, try less toxic alternatives. Only use copper
algaecides if the other alternatives do not work. Ask a pool/spa/hot tub/fountain
maintenance service or store for help resolving persistent algae problems without
using copper algaecides.
Develop and regularly update a facility maintenance plan that follows all discharge
requirements.
Dispose of unwanted chemicals properly. Many of them are hazardous wastes when
discarded.
Store pool chemicals under cover and in enclosed containers.
Required Water Disposal BMPs
All pools and spas regulated by Public Health-Seattle and King County must be
connected to the sanitary sewer for draining pool water, pool wash water and filter
backwash. If the pool or spa does not have a permanent drain connection, then
water must be pumped or drained to the sanitary sewer or meet the following
BMPs.
Discharging pool and spa water if sanitary sewer is not available:
-saltwater and saltwater pool and spa water
o
Have it hauled off-site for disposal at an approved location; or
Infiltrate to ground if all 9 conditions below are met. Saltwater pool
and spa water must not be allowed to flow off-site, nor may it enter
stormwater drainage systems or surface waters. Saltwater discharges
can elevate salt concentrations in your soil and damage vegetation.
-saltwater pools and spas only
o
88
Drain to the stormwater drainage system if all 9 conditions listed
below are met
Conditions for draining to ground (non-saltwater and saltwater pools and spas) or
to a stormwater drainage system (non-saltwater pools and spas only):
1. No copper-based algaecides were used;
2. The water must be tested to determine chlorine levels and pH;
3. The water is dechlorinated to 0.10 ppm Chlorine or less, using neutralizing
chemicals or by letting the pool or spa “sit” long enough to reduce the chlorine level
to the allowable limit. The pool or spa must not be used during this period;
4. The pH is neutral (6-8);
5. Free of any coloration, dirt, suds, or algae;
6. Free of any filter media;
7. Free of acid cleaning wastes;
8. Released at a rate that does not cause erosion either onsite or in the drainage
system; and
9. At ambient temperature.
Saltwater pool and spa water must not be discharged to the stormwater drainage
system. Either infiltrate to ground if all 9 conditions above are met or hire a
professional pool-draining service to collect all water for off-site disposal at an
approved location.
Diatomaceous earth (commonly used as a filtering agent) and water from back
flushing filter systems cannot be discharged to surface waters, storm drainage
systems, septic systems, or the ground. Dispose of diatomaceous earth filter
material as solid waste.
Do not discharge pool or spa water to a septic system, as it is prohibited and may
cause the system to fail.
The discharge of pool and spa filter backwash or cleaning water to the ground,
surface waters or the storm drainage system is not allowed.
Additional Information
al, Chapter 3: Commercial and Multifamily
BMPs
A-3: Storage of Liquid Materials in Portable Containers
o
A-11: Cleaning or Washing of Tools and Equipment
o
A-15: Washing of Buildings, Rooftops, and Other Large Surfaces
o
–477–
kingcounty.gov/stormwater.
89
A-34:Animal Waste
The following best management practices (BMPs) apply to kennels, doggy daycare,
catteries, veterinary clinics, fenced pens, recreational areas, multi-family properties and
other locations where pets (not including livestock) are permitted.
For livestockBMPs see activity sheet A-35: Keeping Livestock in Stables, Pens, Pastures or
Fields.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Regularly sweep and clean areas where animals are kept. Collect, bag, and dispose of
droppings, uneaten food, and other potential stormwater pollutants.
Put pet waste in a securely closed bag and deposit it in the trash. Do not place pet
waste in yard waste containers because pet waste may carry diseases, and
composting may not kill disease-causing organisms.
Do not use pet waste as fertilizer. Harmful bacteria, worms, and parasites that can
transmit disease can live in the soil for years even after the solid portion of the pet
waste has dissolved.
Do not hose down kennels or paved areas where animals are kept to the stormwater
drainage system.
Sweep and clean kennels and paved areas prior to washing the areas. Collect and
dispose of the wash water to the sanitary sewer system or infiltrate the wash water
into grass or gravel if mild soaps or detergents are used. If floor stripping or
disinfectant chemicals are used, the wash water must be hauled off-site for proper
disposal (e.g., taken to a wastewater treatment facility).
Bathe pets indoors or in a manner that wash waterwon’t be discharged to the
stormwater drainage system or surface waters.
Install covered waste containers and provide waste collection service at designated
dog exercise areas.
Supplemental BMPs
Make sure there is vegetative cover or some other type of ground cover, such as
mulch, if animals are kept in unpaved and uncovered areas in order to prevent
erosion.
Specially designed septic systems for kennels are commercially available and are
recommended if the above BMPs are not adequate.
90
Do not dispose of unused pet pharmaceuticals in a storm drain, in a toilet, or down a
sink. For proper disposal refer to King County’s Secure Medicine Return program,
https://kingcountysecuremedicinereturn.org/.
Pet pesticides, such as flea prevention, cannot be disposed of at a medicine return
drop-box. Pesticides should be taken to at a local hazardous waste drop-off location.
Refer to www.hazwastehelp.org for guidelines and to find a drop-off location near
you.
Required BMPs – Recreational Areas and Multi-Family Properties
Post signs at recreation areas and multi-family properties (that allow pets)
reminding residents and visitors to pick up after their pets.
Carefully consider the placement of pet waste stations at recreation sites and near
multi-family properties that allow pets. Choose locations convenient for dog walkers
to pick up a bag at the start of their walk and locations for them to dispose of it at
mid-walk or at the end of their walk.
Check pet waste stations on a regular basis to keep pet waste bags stocked and
disposal stations empty. Consider signage to keep regular trash out of pet waste
disposal stations to avoid filling them too quickly. Make sure pet waste disposal
stations have a cover to keep out water.
At multi-family properties with roof-top dog runs, ensure that stormwater from the
dog run is not discharged to the stormwater system. Check with the local
jurisdiction regarding roof-top dog run connections to sanitary sewer.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-8: Storage of Solid Waste and Food Waste (Including Cooking Grease)
o
A-35: Keeping Livestock in Stables, Pens, Pastures or Fields
o
–477–
kingcounty.gov/stormwater.
91
A-35:Keeping Livestock in Stables, Pens, Pastures or Fields
The following best management practices (BMPs) apply to livestock, including cows,
horses, and other hoofed animals. If a site-specific farm management plan has been
approved by King County, adhere to the BMPs in the plan to minimize pollution generated
from agricultural activities. For information on farm management plans and livestock
management requirements, refer to King County Code 21A.30.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Livestock wash areas may not be plumbed or flow to the stormwater drainage
system or surface waters. Wash water must be discharged to the sanitary sewer,
septic system, or infiltrate into the ground.
Locate soiled bedding and manure piles such that runoff does not flow to the
stormwater drainage system or to surface waters.
Contain bedding to prevent the materials from being blown or washed away into the
stormwater drainage system or surface waters.
Use fencing or dense vegetation to prohibit livestock from entering county owned
storm drain ditches
Properly dispose of spent fluorescent bulbs often used in barns, stables, and arenas.
The mercury containing bulbs should not be stored loosely nor thrown in the
garbage. Find the nearest collection site at www.lightrecycle.org.
When maintaining, repairing, and fueling farm equipment implement BMPs in
activity sheets A-18 Vehicle and Equipment Repair and Maintenance, A-2 Outdoor
Storage of Liquid Materials in Stationary Tanks, and A-3 Storage of Liquid Material
in Portable Containers.
Implement BMPs and specific requirements in accordance with King County Code
21A.30 for livestock management. If BMPs are implemented in accordance with the
livestock management code, then additional BMPs may not be necessary unless they
are not adequate to protect King County surface waters.
Supplemental BMPs
Make sure there is vegetative cover or some other type of ground cover, such as
mulch, if animals are kept in unpavedand uncovered areas in order to prevent
erosion.
Surround the area where animals are kept by a fence or other means that prevents
animals from moving away from the controlled area where BMPs are used.
92
Technical Assistance
TheKing Conservation District can provide technical assistance for the
implementation of livestock management BMPs. Personnel are available for site
visits and can help prepare farm management plans compliant with King County
code.
1107 SW Grady Way, Suite 130
Renton, WA 98057
Telephone: 425-282-1900
Email: district@kingcd.org
http://www.kingcd.org/
–
The Washington State University Cooperative Extension Service offers a variety of
educational services designed to promote sensitivity to water quality concerns in
relation to agricultural production, livestock management, and small farms.
919 SW Grady Way Suite 120
Renton, WA 98055
Telephone: 206-205-3100
http://king.wsu.edu/
Horses for Clean Water offers environmentally sensitive horse keeping education on
manure management, pasture management, mowing, composting, and what
equipment to use.
7235 Southside Boulevard
Nampa, ID 83686
Telephone: 206-909-0225
http://www.horsesforcleanwater.com
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-2: Outdoor Storage of Liquid Materials in Stationary Tanks
o
A-3: Storage of Liquid Material in Portable Containers
o
A-18: Vehicle and Equipment Repair and Maintenance
o
A-34: Animal Waste
o
, Chapter 5: Information Sheets
93
Containment
o
King Conservation District -Healthy Horses, Clean Water
https://kingcd.org/2019/08/29/healthy-horses-clean-water-tips-for-small-
acreages/
Washington State Department of Agriculture – Nutrient Management Plans
https://agr.wa.gov/departments/land-and-water/livestock-nutrients/nutrient-
management-plans
United States Department of Agriculture –Natural Resources Conservation Services
https://www.nrcs.usda.gov/wps/portal/nrcs/site/national/home/
–477–
kingcounty.gov/stormwater.
94
A-36:Logging and Log Yards
The following best management practices (BMPs) apply to activities that fall under the
classification of Class IV General Forest Practices, where timber harvesting is done in the
process of converting forest lands into other land uses, such as forest cutting for
construction of homes.
ediment.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, then you will be required to
take additional measures.
Required BMPs
Comply with King County Code 21A.24 (Critical Areas) requirements for logging
near streams, wetlands, and other sensitive areas, and the
requirements for the clearing and grading of sites.
Apply for coverage under the Washington State Department of Ecology's National
Pollutant Discharge Elimination System (NPDES) permit.
–477–
kingcounty.gov/stormwater.
95
A-37:Mining and Quarrying of Sand, Gravel, and Other
Materials
The following best management practices (BMPs) apply to surface excavation and on-site
storage of sand, gravel, minerals, peat, clay, rock, and other materials that are mined in
unincorporated King County.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Obtain a National Pollutant Discharge Elimination System (NPDES) Sand and Gravel
General Permit for Sand and Gravel Operations, Rock Quarries, and similar mining
facilities.
Obtain a grading permit from King County Local Services Permitting Division
(Permitting).
Comply with King County Code 16.82 (Clearing and Grading). If the grading permit
conditions do not adequately protect surface waters and groundwater, then
additional BMPs will be required under KCC 9.12 (Water Quality).
Maintain stormwater facilities per KCC 9.04 (Stormwater Water Runoff).
Control sediment and erodible materials on-site to prevent track out on to road
right of ways and from entering the storm drainage system.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-41: Wheel Wash and Tire Bath Track Out Control
o
A-44: Dust Control for Commercial Operations
o
, Chapter 5: Information Sheets
Containment
o
Controlling and Collecting Contaminated Runoff
o
Water Quality Treatment BMPs
o
–477–
kingcounty.gov/stormwater.
96
A-38:Well, Utility, Directional and Geotechnical Drilling
The following best management practices (BMPs) apply to drilling water wells and utilities,
environmental protection and monitoring wells, and geotechnical borings that use
machinery in the drilling. It does not apply to the use of devices such as hand augers, or for
large structural drilling such as drilled shafts.
Potent
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Obtain permits for drilling activities, and for clearing and grading the access routes
and the work site. For more information, contact the King County Local Services
Permitting Division at 206-296-6600.
When drilling in known or suspected soil contamination, test and characterize soil
cuttings and accumulated sediment to determine proper management and disposal
methods. If applicable, generator knowledge may be used to characterize the soil
cuttings and accumulated sediment.
Protect environmentally sensitive areas (streams, wetlands, erosion hazards, and
landslidehazards) within the area of influence of the work site. For horizontal
directional drilling, take measures to capture and contain drilling fluids and slurry.
Mitigate potential impacts to surrounding areas and/or the storm drainage system.
The driller must be equipped to quickly respond to spills and unusual conditions
that may arise.
Locate and prepare access roadways to minimize the amount of excavation and the
potential for erosion. See the for
information on vehicle access preparation and maintenance and erosion control
measures.
Containaccumulated uncontaminated water and sediment on-site and pump into a
storage tank or direct through a geotextile filtration system (or equivalent system)
before discharging to the surrounding ground surface.
Keep all sediment-laden water out of storm drains and surface waters. If sediment-
laden water does escape from the immediate drilling location, block flow to any
nearby waterways or catch basins using fabric, inlet protections, sandbags, erosion
fences, or other similar methods. Immediately notify King County Stormwater
Services at 206-477-4811 and the Washington State Department of Ecology at 206-
594-0000, if sediment-laden water impacts the storm drainage system or surface
waters.
97
Divert any concentrated flows of water into the job site using sandbags or check
dams up-slope from the site.
Dispose of soil cuttings and accumulated sediment appropriately. If cuttings or
other soils disturbed in the drilling process are to be temporarily stockpiled on-site,
they must be covered and surrounded by a berm or filter device.
Stabilize exposed soils at the end of the job, using mulch or other erosion control
measures.
Contain spent drilling slurry on-site and allow it to dewater, or haul to an
appropriate, approved, disposal site.
Restore disturbed areas with mulch and seeding or hydroseeding.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-3: Storage of Liquid Materials in Portable Containers
o
A-4: Storage of Soil, Sand, Salt, and Other Erodible Materials
o
A-6: Storage of Contaminated Soils
o
A-10: Treatment, Storage or Disposal of Dangerous Wastes
o
A-11: Cleaning or Washing of Tools and Equipment
o
A-18: Vehicle and Equipment Repair and Maintenance
o
, Chapter 5: Information Sheets
Containment
o
Disposal
o
Kin
–477–4811
kingcounty.gov/stormwater.
98
A-39:Roof Vents and Fugitive Emissions
The following best management practices (BMPs) apply to processes that vent emissions to
a roof and/or the accumulation of pollutants on a roof. Processes of special concern are
stone cutting, metal grinding, spray painting, paint stripping, galvanizing, and
electroplating. Pollutants from these processes may build up on roofs and may contaminate
stormwater roof runoff.
Contact Puget Sound Clean Air Agency and/or the Washington State Department of Ecology
for air pollution control regulations. If your activities are permitted by either of these
agencies, then these requirements are supplemental.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Identify processes that are vented to the roof and may contribute pollutants.
Pollutants of concern include and are not limited to:
metal dust
o
grease from food preparation
o
solvents
o
hydrocarbons
o
fines
o
stone dust
o
Inspect around vents, pipes, and other surfaces for pollutant deposition. Properly
clean up any deposited pollutants, ensuring they are not disposed of into the
stormwater drainage system.
Install appropriate source control measures such as air pollution control equipment
(filters, scrubbers, and other treatment) and/or institute operational or process
changes.
If proper installation and maintenance of air pollution control equipment does not
prevent pollutant fallout on your roof, additional treatment of the roof runoff may
be necessary. Install/provide appropriate devices for roof runoff before it is
discharged off-site. This may include approved water quality treatment BMPs or
structural stormwater treatment systems.
Consider instituting operational or process changes to reduce pollution.
Required Routine Maintenance
99
Maintain air filters and pollution control equipment on a regular basis to ensure
they are working properly. If you smell odors from outside the building, the
pollution control equipment may need maintenance or evaluation.
When cleaning deposited pollutants from roof tops, first clean using dry methods
such as sweeping or vacuuming before using water.
Collect the wash water and loose materials using a sump pump, wet vacuum, or
similar device. Discharge the collected runoff to the sanitary sewer after obtaining
permission from the local sewer authority or have a waste disposal company
remove it.
Additional Information
, Chapter 5: Information Sheets
Disposal
o
Water Quality Treatment BMPs
o
–477–
kingcounty.gov/stormwater.
100
A-40:Street Deicing Operations
The following best management practices (BMPs) apply to deicing and anti-icing
operations on streets and highways to control ice and snow.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Select deicers and anti-icing materials such as sand, calcium chloride, magnesium
acetate, potassium acetate, or similar materials that cause less adverse
environmental impact than urea, and sodium chloride.
Apply de/anti-icing materials only as needed, using minimum quantities. Adhere to
manufacturer and industry standards of use and application.
Store de/anti-icing materials (except for sand) in an impervious containment area
to keep the material from entering stormwater drainage systems or surface waters.
Maintain sand piles so that sand cannot wash into the stormwater drainage system
or surface waters.
Transfer liquid de/anti-icing materials in the containment area or use a drip pan
under the hose connection.
Sweep/clean up accumulated de/anti-icing materials and grit from roads as soon as
possible.
Minimize use of de/anti-icing materialsin areas where runoff or spray from the
roadway immediately enters sensitive areas such as fish-bearing streams.
Supplemental BMPs
Intensify roadway cleaning in early spring to help remove particulates from road
surfaces.
When feasible, use de/anti-icing materials with low amounts of metals.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-4: Outdoor Storage of Soil, Sand and Other Erodible Materials
o
–477–
kingcounty.gov/stormwater.
101
A-41:Wheel Wash and Tire Bath Track Out Control
The following best management practices (BMPs) apply to commercial and industrial
operations where materials may be tracked off-site. If a rocked construction-type entrance
for an unpaved site, or routine sweeping/vacuuming of a paved site, does not control mud
and sediment track out, then a wheel wash system must be installed.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Install a portable wheel wash system, or
Install a permanent wheel wash system as described in Appendix D of the
.
Required Routine Maintenance
Change water as necessary. Dispose of wheel wash water to an appropriate disposal
location. Do not discharge wheel wash water to a stormwater drainage system or
surface waters.
Remove and properly dispose of accumulated sediment from the wheel wash
system as needed.
Maintain the appropriate level of water per design.
Additional Information
St, Chapter 3: Commercial and Multifamily
BMPs
A-11: Cleaning or Washing of Tools and Equipment
o
A-13: Vehicle Washing and Steam Cleaning
o
nual, Chapter 5: Information Sheets
Catch Basin Insert
o
Containment
o
Controlling and Collecting Contaminated Runoff
o
Disposal
o
Water Quality Treatment BMPs
o
Manual
–477–
kingcounty.gov/stormwater.
102
A-42:Potable Water Line Flushing, Water Tank Maintenance
and Hydrant Testing
Best management practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of stormwater,
you will be required to take additional measures.
Required BMPs
Remove solids from associated curbs and gutters before flushing water. Use erosion
and sediment control BMPs such as those found in the
(straw wattles, D.2.1.2.5; and catch basin inlet protection, C.3.9) to
collect any solids resulting from flushing activities.
Discharge water to the sanitary sewer if super chlorination or chemical treatment is
used as part of flushing. If sanitary sewer is not available, the water may be
infiltrated to the ground as long as it:
is dechlorinated to a total residual chlorine concentration of 0.1 ppm or less;
o
meets water quality standards;
o
is discharged through a diffuser to prevent erosion; and
o
does not cross property lines.
o
Discharging water (chlorinated to any degree or dechlorinated) to a stormwater
drainage system requires approval from King County Stormwater Services. The
water must be:
dechlorinated to a total residual chlorine concentration of 0.1 ppm or less;
o
pH adjusted if necessary; and
o
volumetrically and velocity controlled to prevent resuspension of sediments
o
in the municipal separate storm sewer system.
Do not over apply dechlorination products. This can deplete the dissolved oxygen
concentration and reduce the pH in discharge/receiving waters. Dechlorination
products can include ascorbic acid/sodium ascorbate, calcium thiosulfate, sodium
sulfite tablets, sodium thiosulfate, sodium bisulfite or other alternate dechlorination
products.
Supplemental BMPs
If possible, design flushing to convey accumulated materials to strategic locations
such as a treatment facility, preventing resuspension and overflow of the solids
during storm events.
If possible, conduct flushing and tank maintenance activities on non-rainy days and
during the time of the year that poses the least risk to aquatic biota.
Additional Information
103
, Chapter 3: Commercial and Multifamily
BMPs
A-3: Storage of Liquid Materials in Portable Containers
o
ual, Chapter 5: Information Sheets
Water Quality Treatment BMPs
o
–477–
kingcounty.gov/stormwater.
104
A-44:Dust Control for Commercial Operations
The following best management practices (BMPs) apply to existing manufacturing and
commercial operations as opposed to new construction or land development. Material
handling activities may include concrete crushing, cement mixing, commercial composting,
stone grinding, and wood milling.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Sweep paved areas where dust and erodible materials accumulate. Use vacuum
sweepers to minimize generation of airborne dust and for more efficient dust
removal.
Clean equipment and vehicles that leave the property to prevent dust and track out
of material. Create a designated wash area to collect and properly dispose of the
wash water. Never wash down equipment or vehicles to the stormwater drainage
system or to surface waters.
Train employees in the proper operating procedures to minimize dust
accumulation.
Supplemental BMPs
Use dust filtration and collection systems such as bag house filters.
Use water spray to flush dust accumulations to an approved treatment system or
the sanitary sewer where available and allowed by the local sewer authority and the
King County Industrial Waste Program.
Use approved dust suppressants such as those listed in the
Manual, Appendix D: Erosion and Sediment Control Standards.
When pH levels in stormwater rise above 8.5, the pH must be adjusted to the
acceptable range of 6.5 to 8.5. Refer to the
Manual, Appendix D, Sections D.2.2.7 and D.2.2.8 for information on pH adjustment.
Additional Information
Stormwater, Chapter 5: Information Sheets
Catch Basin Insert
o
Controlling and Collecting Contaminated Runoff
o
Water Quality Treatment BMPs
o
Washington State Department of Ecology’s
-433 https://p2infohouse.org/ref/14/13215.pdf. Note that not all
105
dust suppressants are appropriate for use near storm drainage systems or surface
waters.
Contact Puget Sound Clean Air Agency and/or the Washington State Department of
Ecology for air pollution control regulations.
–477–
kingcounty.gov/stormwater.
106
A-45:Maintenance of Public and Private Utility Corridors and
Facilities
The following best management practices (BMPs) apply to maintenance activities
associated with the transmission and distribution of public and private utilities such as
petroleum products, natural gas, water, sewage, and electrical power. This includes the
maintenance of underground utility vaults, pump stations, and similar facilities.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Minimize the amount of herbicides and other pesticides used to maintain access
roads and facilities.
Stabilize access roads or areas of bare ground with gravel, crushed rock, or another
method to prevent erosion. Use and manage vegetation to minimize bare
ground/soils that may be susceptible to erosion.
Provide stormwater drainage for roads and maintenance areas. Grade roads with a
crown or slope to minimize the potential for erosion from runoff. Provide ditches,
swales, and culverts to convey stormwater runoff.
Keep ditches and culverts properly clear to reduce the possibility of the drainage
becoming plugged or blocked, which could cause overflows and erosion.
Check utility vaults or other underground structures for oil prior to pumping out
any collected water. Contaminated water must be collected for proper disposal.
Small amounts of oil may be captured with absorbent material. Never discharge
contaminated water, including oil, sediment, or high or low pH, to stormwater
drainage systems, stormwater drainage facilities or surface waters.
When removing water and/or sediment from electrical transformer vaults,
determine from records or testing if the transformers contain PCBs. Properly
dispose of accumulated water and sediment from these vaults.
Clean up any debris or spilled material immediately after completing maintenance
and repair activities.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-3: Storage of Liquid Materials in Portable Containers
o
A-5: Storage and Use of Pesticides and Fertilizers
o
A-22: Painting, Finishing and Coating of Vehicles, Products and Equipment
o
107
A-26: Landscaping Activities, Vegetation Management, and Irrigation
o
Manual, Appendix D: Erosion and Sediment
Control Standards
Work in public road right of ways requires permission from King County Utility
Inspection Program, call 206-296-8122.
–477–
kingcounty.gov/stormwater.
108
A-46:Color Events
The following best management practices (BMPs) apply to color events which include
charity, religious, or commercial events that involve the use of powdered and/or liquid
dyes. Because they typically occur outside, there is a high likelihood of the color material
entering stormwater drainage systems and surface water unless measures are taken to
prevent these illicit discharges from occurring.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Pre-event BMPs
Call King County Stormwater Services at 206-477-4811 and ask to speak to a source
control inspector for specific approval requirements and to arrange a pre-event site
visit and/or consultation. Every event will have site specific stormwater
considerations.
Create a map of your event that includes the following: event route; nearby streams,
lakes and ponds; start and finish areas; color application stations/areas; and the
catch basin inlets and open stormwater features (e.g. ditches, swales, bioretention,
rain gardens) at the color application, start and finish areas.
Create a Pollution Prevention Plan that details the measures taken to ensure that NO
dye material, either during or after the event, will enter the stormwater drainage
system and how all dye material will be removed and disposed of. The plan must
address what will happen in the event of rain. Include emergency phone numbers
for King County Stormwater Services, 206-477-4811, in case dye material enters the
stormwater drainage system or surface waters.
Contract with a commercial street cleaning company to clean paved surfaces. Have
a storm drain cleaning contractor on-call for discharges to stormwater drainage
systems or emergency clean-up if necessary. Ensure the commercial street cleaning
firm has a plan in place for the proper disposal of sweepings from the event and
associated air filters.
All clean-up must be completed prior to the next forecasted rainfall, no later than
24-hours after the event.
Request a copy of the dye product’s safety data sheet (SDS) from the manufacturer
or supplier. Review SDS for potential safety and environmental hazards.
Provide copies of the map, pollution prevention plan, commercial cleaning contract,
dye material SDSs, and the names and contact information of the event officials to
the local stormwater agency. This information shall be submitted at least 3 weeks
prior to the event.
109
Preventing runoff from entering storm drain systems and water bodies:
Protect storm drains by using berms and covering the drains with tarps or catch
basin covers.
Prohibit participants from throwing dye within 100 feet of any stream, ditch, or
water body.
Set up color stations at least 100 feet away from any stream, ditch, or water body.
The route, start, finish, and color application stations must be at least 100’ away
from any permeable pavement or the permeable pavement must be completely
covered.
If the event will be held on a small, contained area, cordon off the area and place
enough covers on the ground to cover the entire site. If possible, contain the color
application to grassy areas where ground covers are unnecessary.
Event clean-up BMPs
Dry off tarps and stained wet pavement with towels or absorbent pads.
Use brooms or street sweepers to clean up paved areas. The fineness of the material
may require sweepers with dust control systems.
Use care when removing berms, covers and tarps to ensure no dye enters the storm
drains.
Do not use blowers to move dye material.
Do not use hoses or pressure washers to rinse excess dye off of tarps, sidewalks, or
paved areas.
If it becomes necessary to use water to clean surfaces, all the water must be
collected and disposed of to the sanitary sewer system, with approval from the local
sewer agency.
Call King County Stormwater Services immediately (24/7) if any colored water
enters a stormwater drainage system or water body.
All litter and debris must be picked up and properly disposed of.
“Biodegradable” and “non-toxic” do NOT mean that a substance can go into
stormwater drainage systems or water bodies. The dye material can harm aquatic
organisms by altering water quality and chemistry. State and federal environmental
laws require local jurisdictions to prohibit non-stormwater discharges to storm
drains. Dye material and any wash water are prohibited non-stormwater
discharges.
Additional Information
, Chapter 5: Information Sheets
Catch Basin Insert
o
Containment
o
Controlling and Collecting Contaminated Runoff
o
Drainage Maintenance Contractors
o
110
Spill Response and Cleanup Plan
o
–477–4811
kingcounty.gov/stormwater.
111
A-47:Older Stationary Fueling Operations
The following best management practices (BMPs) apply to the fueling of vehicles and
equipment, including gas stations and fuel pumps to service equipment or vehicles, where
the fuel pumps were installed prior to July 1995.
For new or remodeled fueling areas installed after July 1995, see activity sheet A-17:
Stationary Fueling Operations. For mobile fueling operations see activity sheet A-48:
Mobile Fueling of Vehicles and Heavy Equipment. For farm and agricultural operations
with above ground fuel tanks, refer to activity sheet A-2: Outdoor Storage of Liquid
Materials in Stationary Tanks. For in-water and over-water fueling operations, see activity
sheet A-30: Marine Activities.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Pave and contain the fueling area with impervious concrete (e.g., Portland cement).
The fueling area (spill containment pad) shall have a sill or berm raised to a
minimum of four inches to prevent the runoff of spilled liquids and to prevent run-
on of stormwater from the surrounding area. Raised sills are not required at the
open-grate trenches that connect to an approved drainage-control system.
Cover the fueling area with a roof or canopy or in lieu of covering the fueling area (if
the fuel pumps were installed prior to July 1995):
Maintain spill materials and drip pans at all times next to the fueling area.
o
For non-retail fueling operations, post a sign stating that a drip pan must be
o
used during fueling and that all spills and drip must be cleaned up
immediately.
Should subsequent inspections find evidence of spilled fuel on the ground or
o
stormwater contamination, then the fueling area must be covered.
Drains from the spill containment pad of a fueling areas with a roof or canopy must
have a normally closed shutoff valve. The valve may be opened to convey
stormwater with residual contamination to an oil control treatment system (e.g., an
oil/water separator, catch basin insert, or equivalent treatment) which then
discharges to:
At a minimum, a basic treatment system (e.g., sand filter, filter strips, water
o
quality vault) prior to discharging to a storm drainage system, surface water
or ground; or
112
a sanitary sewer. Approval from the local sewer authority is required for
o
conveyance of any fuel-contaminated stormwater to a sanitary sewer. State
and local regulations prohibit discharges that could cause a fire or explosion
(WAC, Section 173-216-060; KCC 28.84.060). For conveyance to the sanitary
sewer, a catch basin shall be installed upstream of the oil control treatment
system, and a normally closed shutoff valve is required at the discharge point
of the oil control treatment system.
In the case of a fuel spill, spilled fuel must be pumped from the drains or catch
basins and must be treated and disposed of offsite in accordance with Department
of Ecology regulations. The valve may only then be opened to convey stormwater
with residual contamination.
Discharges from the treatment systems (oil control treatment system and basic
treatment system) to storm drainage systems, surface water or to the ground must
not display ongoing or recurring visible sheen and must not contain oil or grease.
Alternatively, collect runoff from the spill containment pad in a dead-end sump and
hold for proper off-site disposal. The dead-end sump must be easily inspected,
maintained, and pumped.
If a roof or canopy is infeasible, then the concrete fueling pad must be equipped with
emergency spill control features including a shutoff valve for drainage from the
fueling area. The drainage shutoff valve may be kept open to convey stormwater
with residual contamination from the fueling pad.
Maintain the valve in the closed position during a spill event and cleanup. An
electronically actuated valve is preferred to minimize the time lapse between spill
and containment.
In the case of a fuel spill, spilled fuel must be pumped from the drains or catch
basins and must be treated and disposed of offsite in accordance with Department
of Ecology regulations. The valve may only then be reopened to convey stormwater
with residual contamination.:
to a sanitary sewer, if approved by the sewer authority, or
o
to an oil control treatment system (e.g., an oil/water separator, catch basin
o
insert, or equivalent treatment), and then, at a minimum, to a basic treatment
system (e.g., sand filter, filter strips, water quality vault). Discharges from
treatment systems to storm drain system or surface water must not display
ongoing or recurring visible sheen and must not contain oil or grease.
Required Operational BMPs
Train employees on the proper use of fuel dispensers.
Use drip pans or absorbent pads under all hose connections to capture drips or
spills during fuel transfers.
Post signs in accordance with the Uniform Fire Code (UFC) or International Fire
Code (IFC). Post “No Topping Off” signs. Topping off fuel tanks results in spillage and
vents gasoline fumes to the air. Post signs that ban customers and employees from
changing engine oil or other fluids at that location.
113
The person conducting the fuel transfer must be present at the fueling pump during
fuel transfer. It is encouraged to post “Stay with Vehicle During Fueling” signage
near fuel dispensers.
Make sure that the automatic shutoff on the fuel nozzle is functioning properly.
Prepare an emergency spill response and cleanup plan. Have designated trained
person(s) available either on-site or on call at all times to implement the plan
promptly and properly and immediately cleanup all spills.
Keep suitable cleanup materials,such as dry adsorbent materials, on-site to allow
prompt cleanup of a spill. Do not use dispersants or soap to clean up spills or sheens.
Immediately notify Ecology, the local jurisdiction, and the local sewer authority if a
spill may reach sanitary or storm sewers, ground water, or surface water, in
accordance with federal and Ecology spill reporting requirements.
Sweep or vacuum up sediment and debris in the fueling area as needed. Never hose
down the fueling area to the storm drains. Contaminated runoff must be collected
for proper disposal.
Keep drained oil filters in a closed, leak-proof container or drum.
Transfer the fuel from the delivery tank trucks to the fuel storage tank over
impervious, contained areas and ensure that appropriate overflow protection is
used. Alternatively, cover nearby storm drains during the filling process and use
drip pans under all hose connections.
Store and maintain appropriate spill cleanup materials in a location known to all
employees.
Supplemental BMPs
Use absorbent materials in or around catch basin inlets on the property to filter oily
runoff. Properly dispose of absorbent materials.
Install a catch basin insert configured for oil removal. The oil absorbent filter media
must retain absorbed oil during future storm events.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-2: Outdoor Storage of Liquid Materials in Stationary Tanks
o
A-11: Cleaning or Washing of Tools and Equipment
o
A-13: Vehicle Washing and Steam Cleaning
o
A-17: Stationary Fueling Operations
o
A-18: Vehicle and Equipment Repair and Maintenance
o
A-30: Marine Activities
o
A-31: Parking Lots, Driveways and Outside Storage Areas
o
A-48: Mobile Fueling of Vehicles and Heavy Equipment
o
, Chapter 5: Information Sheets
114
Catch Basin Insert
o
Containment
o
Covering
o
Oil/Water Separators
o
Spill Response and Cleanup
o
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115
A-48:Mobile Fueling of Vehicles and Heavy Equipment
The following best management practices apply to mobile fueling, also known as fleet
fueling, wet fueling, or wet hosing. Mobile fueling is the practice of filling fuel tanks of
vehicles or equipment by fuel tank trucks, tank trailers, and trucks with accessory fueling
tanks that are driven to the yards or sites where the vehicles to be fueled are located.
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required Operational BMPs
Obtain approval from the local fire department. Comply with local and Washington
State fire codes.
The driver/operator must be present and constantly observe all fuel transfer
operations to ensure the implementation of the following procedures at all fuel
transfer locations:
To the extent practical, locate the point of fueling at least 25 feet from the
o
nearest storm drain or drainage ditch, or inside an impervious containment
with a volumetric holding capacity equal to or greater than 110 percent of
the fueling tank volume, or covering the catch basin to prevent discharge of
spilled or leaked fuel. Covers arenot required for storm drains that convey
the inflow to a spill control separator approved by the local jurisdiction and
the fire department;
Place a leak-proof drip pan or an absorbent pad under each fueling location
o
prior to and during all dispensing operations. The pan or the absorbent pad
must have a capacity of at least 5 gallons. There is no need to report spills
retained in the drip pan or the pad;
Manage the handling and operation of fuel transfer hoses and nozzle, drip
o
pan(s), and absorbent padsas needed to prevent spills/leaks of fuel from
reaching the ground, storm drains, or surface waters;
Do not extend fueling hoses across a traffic lane without fluorescent traffic
o
cones, or equivalent devices, conspicuously placed to block all traffic from
crossing the fuel hose;
Remove the fill nozzle and cease filling the tank when the automatic shut-off
o
valve engages. Do not lock automatic shutoff fueling nozzles in the open
position;
Do not “top off” the fuel tanks; and
o
Do not use dispersants or soap to clean up spills or sheens.
o
116
Develop and follow a mobile fueling plan that includes the required operational
BMPs and spill response procedures.
The responsible manager shall:
Sign and date the mobile fueling plan;
o
Distribute mobile fueling procedures to all operators; and
o
Update and retain the mobile fueling plan in the organization files.
o
Immediately notify the local fire department (911) and Washington State
Department of Ecology in the event of any spill entering surface or ground waters.
Establish a “call down list” to ensure the rapid and proper notification of
management and government officials should any significant amount of product be
lost off-site. Keep the list in a protected but readily accessible location in the mobile
fueling truck. The “call down list” should also pre-identify spill response contractors
available in the area to ensure the rapid removal of significant product spillage into
the environment.
Train the driver/operator upon hiring, and annually thereafter, on proper fueling
procedures, spill prevention, cleanup measures, and emergency procedures. Make
all employees are aware of the significant liability associated with fuel spills.
The driver/operator of the fueling vehicle must have:
A current copy of the mobile fueling plan;
o
Adequate flashlights or other mobile lighting to view fuel fill openings with
o
poor accessibility; and
-way communication with the operator’s home base.
o
Maintain a minimum of the following spill clean-up materials in all fueling vehicles,
that are readily available for use:
-water absorbents capable of absorbing at least 15 gallons of diesel fuel;
o
A catch basin plug or cover kit;
o
Two, five-gallon buckets with lids or sealable disposal bags;
o
A non-spark generating shovel; and
o
For fuel tankers and trailers with fueling tanks greater than 100 gallons, a
o
non-water absorbent containment boom, minimum 10 feet in length with a
12-gallon minimum absorbent capacity.
Use automatic shutoff nozzles for dispensing the fuel. Replace automatic shut-off
nozzles as recommended by the manufacturer.
Maintain fueling equipment, particularly hoses and nozzles.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-3: Storage of Liquid Materials in Portable Containers
o
, Chapter 5: Information Sheets
117
Controlling and Collecting Contaminated Runoff
o
Spill Response and Clean-upPlan
o
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kingcounty.gov/stormwater.
118
A-49:Nurseries and Greenhouses
The following best management practices (BMPs) apply to commercial container plant,
greenhouse grown, cut foliage, and cannabis production operations.
PCBs,
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of surface water and stormwater, you will be
required to take additional measures.
Required Operational BMPs
Establish nursery composting areas, soil storage, and mixing areas as far away as
possible from surface waters and stormwater drainage systems.
Do not blow, sweep, or otherwise allow vegetation or other debris into stormwater
drainage systems or surface waters.
Regularly clean up spilled potting soil, especially if fertilizers and pesticides are
incorporated.
Cover soil storage and compost storage piles. Refer to activity sheet A-4: Outdoor
Storage of Soil, Sand and Other Erodible Materials.
Dispose of pathogen-laced potting substrate and diseased plants appropriately.
Place plants on gravel, geotextile, or weed cloth to allow infiltration and minimize
erosion, including inside greenhouse structures.
Properly store, reuse, recycle, and dispose of used polyfilm, containers, and other
plastic-based products so that they do not collect stormwater.
Evaluate and manage irrigation to reduce runoff, sediment transport, and erosion.
Refer to activity sheet A-26: Landscaping Activities, Vegetation Management, and
Irrigation
Required Structural BMPs
Control stormwater and irrigation runoff. Either:
Collect runoff in a small basin and reuse the runoff,
o
Route runoff through an onsite vegetative treatment area, or
o
Use a graveled area and allow runoff to infiltrate.
o
Surround soil storage and compost storage areas with a berm or wattles.
Use groundcover, such as geotextile fabric or mulch, to stabilize disturbed areas and
prevent erosion in areas where vegetative cover is not an option.
In areas with heavy traffic (foot or machine), use appropriate aggregate such as rock
and gravel for stabilization.
119
Store potting substrate that contains fertilizer in a dedicated area with an
impermeable base. If the storage area is not under a roof to protect it from rainfall,
then manage runoff so that no substrate enters the storm drain system or surface
waters.
Supplemental BMPs – Operational
Use soil mixing and layering techniques with composted organic material to reduce
herbicide use and watering.
Utilize soil incorporated with fertilizers and/or pesticides immediately; do not store
for extended periods.
Irrigation:
Place irrigation emitters primarily in the plant’s root zone. This will
o
significantly reduce nutrient related impacts from fertilizers.
Avoid over-irrigating. This may exceed the soil’s water-holding capacity and
o
lead to run-off or leaching
Consider, and adjust as needed, the uniformity of application, the amount of
o
water retained within the potting substrate, and the amount of water that
enters containers compared to that which exits the containers and/or falls
between containers.
Consolidate containers and turn off irrigation in areas not in production. This
o
may require individual on/off valves at each sprinkler head.
Based on the stage of plant growth, space containers and flats as close as
o
possible to minimize the amount of irrigation water that falls between
containers.
Group plants of similar irrigation needs together.
o
Consider minimizing water losses by using cyclic irrigation (multiple
o
applications of small amounts). Consider using sub-irrigation systems (e.g.
capillary mat, ebb-and-flow benches, and trays or benches with liners); these
systems can conserve water and reduce nutrient loss, particularly when
nutrients are supplied in irrigation water that is reused.
Supplemental BMPs – Structural
Use windbreaks or other means (e.g. pot in pot) to minimize plant blow over.
Cover potting areas with a permanent structure to minimize the loss of soil. Use a
temporary structure if a permanent structure is not feasible.
Additional Information
, Chapter 3: Commercial and Multifamily
BMPs
A-3: Storage of Liquid Materials in Portable Containers
o
A-4: Outdoor Storage of Soil, Sand and Other Erodible Materials
o
A-5: Storage and Use of Pesticides and Fertilizers
o
A-11: Cleaning or Washing of Tools and Equipment
o
120
A-24: Commercial Composting
o
A-26: Landscaping Activities, Vegetation Management, and Irrigation
o
Washington State Department of Ecology’s Regu
Operations
https://appswr.ecology.wa.gov/docs/WaterRights/wrwebpdf/Guidance4Cannabis
Operations.pdf
o–477–
kingcounty.gov/stormwater.
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4.0RESIDENTIAL (NON-COMMERCIAL)
BMPS
This chapter consists of a series of activity sheets listing the best management practices
(BMPs) that are required for single family residential activities in unincorporated King
County. They address typical household activities that have the potential to pollute
stormwater, surface waters, and groundwater.
Even small amounts of commonly used household products such as motor oil, pesticides,
paint waste, and soaps are harmful to aquatic life. Although individual activities may
appear insignificant, runoff from urban areas is now a leading cause of water pollution in
rivers, lakes, and coastal areas.
King County's goal is to reduce pollution by educating homeowners and residents to
prevent the contamination of stormwater runoff and our streams, rivers, lakes, and
groundwater.
For commercial activities occurring on single family residential properties, the BMPs in
Chapter 3 must be implemented in order to protect stormwater quality. This includes
home occupations that have an outdoor component such as guest or employee parking
areas or outdoor storage.
122
R-1:Residential Automobile and Boat Washing
The following best management practices (BMPs) apply to washing vehicles and boats at
your house. Vehicle washing is one of the most common residential activities that pollute
streams, creeks, lakes, and Puget Sound. Evensoaps that are labeled "biodegradable,"
"environmentally friendly", or "nontoxic" are harmful to aquatic life and water quality. The
“nontoxic” label simply means the soap is less toxic to humans. The most environmentally
responsible thing to do is to take your vehicle to a commercial car wash where wash water
is properly recycled and discharged to the sanitary sewer.
PCBs,
BMPs are required by King County Water Quality Code (KCC 9.12). If the BMPs included
here are not enough to prevent contamination of stormwater, you will be required to take
additional measures.
Required BMPs
Washing may only be done in an area that allows for infiltration of the wash water,
such as gravel, grass, or loose soil.
When washing vehicles or boats, use a mild detergent or soap that is pH neutral.
Never clean or pressure wash the engine or undercarriage of your vehicle at home.
The pollutants from this activity can contaminate your property or well water.
Dispose of any remaining soapy water in your wash bucket down the toilet or sink.
Do not wash or rinse vehicles on permeable pavement or pavers.
If you wash on an impermeable (conventional) paved area such as your driveway
and use soaps or detergents, you must do one of the following:
Redirect the wash water to vegetated areas such as the lawn using temporary
o
measures such as a berm, boom/socks, or other solid materials like a piece of
lumber placed at the low point of where your vehicle is parked. This will
redirect the flow of water to the vegetated area where it can infiltrate into
the ground; or.
Use a wet vacuum or pump to collect the wash water and then dispose of the
o
water in your sink or toilet for treatment at your local sewage treatment
plant.
Tips
Use a hose nozzle with a trigger and shut it off when you’re not using it to conserve
water.
There are several waterless car wash products on the market. Cloths, rags, etc. used
with these products should be disposed of as solid waste.
123
Do not take your car to a “charity car wash” unless you can see that the wash water
is being collected and discharged to the sewer system. When in doubt, ask the event
organizers where the car wash water is being disposed of.
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kingcounty.gov/stormwater.
124
R-2:Residential Storage of Solid Waste and Food Wastes
(Garbage)
Leaking garbage cans, waste containers without lids, and scrap piles can cause polluted
runoff, which can harm surface waters and groundwater. Accumulated garbage can attract
rodents, rats, mosquitoes, and other pests that are also health hazards.
pollutants.
Best Management Practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of stormwater,
you will be required to take additional measures.
Required BMPs
Keep garbage, recyclables, and food wastes in covered or lidded containers.
Dispose of waste, using a curbside pick-up service or take it to a solid waste transfer
station.
Do not let garbage accumulate to the point that it spills out of the container or
prevents people from using the container.
Tips
Recycle as much as possible. Use the King County “What do I do with…?” website to
find businesses that accept materials for recycling, donations and disposal
https://info.kingcounty.gov/services/recycling-garbage/solid-waste/what-do-i-do-
with/
King County Solid Waste Division waste disposal information
http://your.kingcounty.gov/solidwaste/index.asp
Household hazardous waste disposal: www.hazwastehelp.org, or contact the
Household Hazards Line at 206-296-4692. See activity sheet R-4: Residential
Hazardous Waste Use, Storage, and Disposal for more information.
Composting yard and food waste
http://your.kingcounty.gov/solidwaste/composting/index.asp
Yard waste collection http://your.kingcounty.gov/solidwaste/garbage-
recycling/yardwaste.asp
Dispose of pet waste in your garbage, see activity sheet R-8: Residential Animal
Waste
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125
R-3:Residential Vehicle Repair and Maintenance
Many people repair and maintain their vehicles at home. Keeping your vehicle from leaking
oil or other fluids is an important pollution prevention measure. These activities cannot
pollute streams, rivers, and lakes.
Best Management Practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of stormwater,
you will be required to take additional measures.
Required BMPs
Collect all used oil, antifreeze, and other vehicle fluids in containers with tight fitting
lids. Do not mix these fluids in the same container.
Recycle oil at an auto parts store or service station. Oil and other fluids can be
disposed of at a household hazardous waste collection site. Call the household
hazardous waste line at 206-296-4692 or see
https://www.hazwastehelp.org/HHW/disposal-locations.aspx for recycling and
disposal information and locations. Never dispose of any fluids or waste materials
into the stormwater drainage system, surface waters, or onto the ground.
Never clean the engine or undercarriage of your vehicle at home. For this type of
cleaning, take the vehicle to a commercial car wash facility.
Use drip pans, tarps, or even cardboard and newspaper under the vehicle to capture
leaks or spills that may occur during maintenance and repair activities. This ensures
spilled fluids won't be washed to the stormwater drainage system.
Clean up spills with rags or absorbent material, such as sand, dirt, or cat litter. Do
not wash down spills. Sweep up absorbents and dispose of them as garbage.
Store used batteries under cover and off the ground or inside until they can be
recycled.
Tips
Take your vehicle to a commercial car repair facility where fluids are handled,
recycled, and disposed of properly.
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R-4:Residential Hazardous Waste Use, Storage and
Disposal
A variety of hazardous materials are routinely used in and around our homes including
chemical cleaners, pesticides, paints, solvents, lighter fluid, gasoline, antifreeze, brake fluid
and other automotive products, wood preservatives and even batteries from our electronic
equipment.
Improper disposal and failure to keep hazardous products from rainwater contact may
cause surface water and groundwater pollution. With so many hazardous materials present
in thousands of households in King County, the cumulative adverse effects of poor usage,
storage and disposal practices are potentially severe to human and environmental health.
pollutants.
Best Management Practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of stormwater,
you will be required to take additional measures.
Required BMPs
Store all hazardous materials inside a building, shed or under cover. Do not expose
hazardous materials to rainwater.
Use products only as specified on labeling directions.
Carefully follow disposal directions on containers of chemicals.
Never discharge or dump hazardous chemicals into storm drainage systems or on to
the ground.
Disposal Options
Dispose of and recycle hazardous wastes through the Household Hazardous Waste
Program or other recycling programs or businesses. There are three fixed
hazardous waste collection sites for household hazardous waste in Seattle and King
County. See www.hazwastehelp.org/ or call the Household Hazards Line at 206-
296-4692 for more information.
Tips
Use the least toxic product available. See
https://kingcountyhazwastewa.gov/en/households-disposal/households-safer-
home-products for information on finding alternatives to hazardous household
products.
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127
R-5:Residential Gardening, Lawn Care, Irrigation and
Fertilizer Application
Many pollutants can enter stormwater systems, groundwater, and water bodies as a result
of typical lawn and gardening work. Runoff contaminated by pesticides and fertilizers can
severely degrade streams and lakes and adversely affect fish and other aquatic life.
Disposal of grass clippings and other vegetation into water bodies leads to decreased
oxygen levels that can be lethal to fish and other aquatic life. In addition, disposal of leaf
litter and other debris to the storm drain system can clog drainage pipes, leading to street
flooding and increased maintenance costs. Some gardening chemicals are also harmful to
children and pets.
nutrients
Best Management Practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of stormwater,
you will be required to take additional measures.
Required BMPs
Never apply herbicides, insecticides, rodenticides, or fungicides near water or when
it is raining.
Manually or mechanically remove weeds and other pests rather than using
pesticides near water.
Store all bags, piles, and containers of fertilizers and pesticides in a covered location
such as a garden shed.
Do not sweep, blow, or dump grass clippings, leaves, or twigs into any street,
drainage ditch, storm drain, or surface waters. Instead, collect and either compost it
or dispose as yard waste.
Store piles of erodible materials, such as topsoil, on lawns or other pervious areas. If
these materials are stored on impervious areas such as driveways, cover them with
a tarp so they are not washed into storm drains or ditches.
Control lawn and garden watering so that no runoff leaves your property. Check
automatic sprinkler systems to ensure there is no overspray to driveways and
sidewalks that drain to storm drainage systems.
Tips
Compost your yard waste, or use it as mulch in your yard or garden. Contact your
local solid waste utility to see if yard waste pickup service is available. See
http://your.kingcounty.gov/solidwaste/garbage-recycling/yardwaste.asp.
Use as little pesticide as possible and always follow the label directions for
application. Try pest control measures that do not require chemicals first.
128
Learn about alternatives to chemical pesticides and fertilizers. Contact the King
County Hazardous Waste Management Program at 206-296-4692, or visit
http://www.hazwastehelp.org
and the Garden Hotline at
https://gardenhotline.org/
Avoid planting species on the Noxious Weeds list. For assistance or questions
contact King County’s Noxious Weed Program at 206-296-1900 or visit
https://www.kingcounty.gov/services/environment/animals-and-plants/noxious-
weeds.aspx.
For additional information on pesticides and fertilizers see activity sheet A-5:
Storage and Use of Pesticides and Fertilizers.
For additional information on vegetation management and irrigation see activity
sheet A-26: Landscaping Activities, Vegetation Management, and Irrigation.
206–477–
kingcounty.gov/stormwater.
129
R-6:Residential Home Maintenance and Repair
There are a variety of home maintenance and repair activities that have the potential to
adversely affect our streams, rivers, and lakes. Pollutants generated from these activities
can affect whether a water body is swimmable or fishable.
Best Management Practices (BMPs) are required by King County Code 9.12. If the BMPs
included here are not enough to prevent contamination of stormwater, you will be required
to take additional measures.
Required BMPs
Do not dispose of wastewater into the street, gutter, storm drain, drainage ditch, or
surface water (e.g., stream, creek, or any other body of water).
Painting
Do not dispose of wash water from cleaning brushes, paint rollers, paint buckets, or
containers to surface water, storm drains, or ditches.
Wash water from latex paints can be disposed of to the sanitary sewer (down a sink
or toilet).
Empty containers of latex paint can be left open to dry out any residual paint, and
then, once a solid, can be disposed of in your normal garbage or taken to a transfer
station for disposal.
Residual oil-based paint, paint thinners, and solvents must be disposed of as
hazardous waste.
Washing
Water from washing decks, driveways, roofs, or other hard surfaces may contain
suspended solids and other pollutants that should not be directly discharged to
stormwater drainage systems.
Redirect wash water to vegetated areas or areas such as gravel, lawns, landscaping,
or bare soil where the water will infiltrate slowly into the ground. If this cannot be
accomplished, then filter the wash water through filter fabric, or other filtering
media to collect the suspended solids before discharging the water to a stormwater
drainage system.
If any chemicals, soaps or detergents are used the wash water must be collected
and disposed of in a sanitary sewer system (i.e., a sink or toilet) or infiltrated on-
site. Do not dispose of this wash water to the stormwater drainage system or
surface waters.
If moss control or another chemical treatment is used during the washing of roofs,
then disconnect the downspouts so the chemicals do not discharge to the
130
stormwater drainage system. Disperse this wash water onto adjacent lawns and
landscaping to infiltrate.
Carpet Cleaning
Most commercial carpet cleaners have onboard wastewater recycling systems. If
you do your own carpet cleaning, then the wash water must be discharged to the
sanitary sewer or your septic system.
Filter the water if it contains lint or other particles to avoid clogging the drains.
If you prefer not to discharge the water to your septic system, you may also
discharge the water to your lawn or a landscaped area to allow the wash water to
infiltrate slowly into the ground.
Be aware that detergents and other cleaning chemicals such as solvents can be
harmful to vegetation and septic systems.
Discharging wash water to the ground may not be allowed if you live in a critical
aquifer recharge area. For additional information on critical aquifer recharge areas
in King County, refer to King County Code 21A.24.311-316.
Never dispose of carpet cleaning wash water to a storm drain, drainage ditch, or
surface water. Carpet cleaning wastewater contains chemicals, detergents, and
suspended solids that adversely impact the quality of surface and ground waters.
Cement/Concrete Work
Concrete/cement wash water has a pH level that is toxic to aquatic life.
Do not allow wash water from concrete work to discharge into stormwater drainage
systems, including small yard drains or adjacent roadways.
This is especially important when installing washed aggregate driveways or patios.
Direct the wash water to vegetated areas or dig a hole where the wash water can
settle and infiltrate slowly into the ground. The cement residue can be mixed into
the soil where the wash water is infiltrated with no detrimental effects, and the pH
will be neutralized.
Tips
Hire a professional home maintenance and repair company that follows the
approved BMPs for home repair and maintenance. If you have questions about
which BMPs a business must comply with contact King County Stormwater Services
at 206-477-4811 or visit www.kingcounty.gov/stormwater.
Remember, as a homeowner, you have a responsibility to ensure your contractors
follow these required BMPs and all King County codes and regulations.
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131
R-7:Residential Swimming Pool and Hot Tub Maintenance
Improper drainage or discharge of water from swimming pools, hot tubs, or spas to storm
drains or ditches during maintenance activities can lead to pollution of streams, rivers, and
lakes. Chemicals used in pool, spa, and hot tub maintenance can contaminate stormwater
and surface water if they are not stored, used, and disposed of correctly.
Best Management Practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of stormwater,
you will be required to take additional measures.
Required Operational BMPs
Clean the pool, spa, hot tub, or fountain regularly.
Maintain proper chlorine levels, water filtration, and circulation, which will limit the
need to drain the facility.
Manage pH and water hardness to reduce copper pipe corrosion that can stain the
facility and pollute receiving waters.
Before using copper algaecides, try less toxic alternatives. Only use copper
algaecides if the other alternatives do not work. Ask a pool/spa/hot tub/fountain
maintenance service or store for help resolving persistent algae problems without
using copper algaecides.
Develop and regularly update a facility maintenance plan that follows all discharge
requirements.
Dispose of unwanted chemicals properly. Many of them are hazardous wastes when
discarded.
Store pool chemicals under cover and in enclosed containers.
Required Water Disposal BMPs
If the pool or spa does not have a permanent drain connection, then water must be
pumped or drained to the sanitary sewer or meet the following BMPs.
Discharging pool and spa water if sanitary sewer is not available:
-saltwater and saltwater pool and spa water
o
Have it hauled off-site for disposal at an approved location; or
Infiltrate to ground if all 9 conditions below are met. Saltwater pool
and spa water must not be allowed to flow off-site, nor may it enter
stormwater drainage systems or surface waters. Saltwater discharges
can elevate salt concentrations in your soil and damage vegetation.
-saltwater pools and spas only
o
Drain to the stormwater drainage system if all 9 conditions listed
below are met
132
Conditions for draining to ground (non-saltwater and saltwater pools and spas) or
to a stormwater drainage system (non-saltwater pools and spas only):
1. No copper-based algaecides were used;
2. The water must be tested to determine chlorine levels and pH;
3. The water is dechlorinated to 0.10 ppm Chlorine or less, using neutralizing
chemicals or by letting the pool or spa “sit” long enough to reduce the chlorine level
to the allowable limit. The pool or spa must not be used during this period;
4. The pH is neutral (6-8);
5. Free of any coloration, dirt, suds, or algae;
6. Free of any filter media;
7. Free of acid cleaning wastes;
8. Released at a rate that does not cause erosion either onsite or in the drainage
system; and
9. At ambient temperature.
Saltwater pool and spa water must not be discharged to the stormwater drainage
system. Either infiltrate to ground if all 9 conditions above are met or hire a
professional pool-draining service to collect all water for off-site disposal at an
approved location.
Diatomaceous earth (commonly used as a filtering agent) and water from back
flushing filter systems cannot be discharged to surface waters, storm drainage
systems, septic systems, or the ground. Dispose of diatomaceous earth filter
material as solid waste.
Do not discharge pool or spa water to a septic system, as it is prohibited and may
cause the system to fail.
The discharge of pool and spa filter backwash or cleaning water to the ground,
surface waters or the storm drainage system is not allowed.
Tips
Hire a professional maintenance company to service your pool, hot tub, or spa.
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kingcounty.gov/stormwater.
133
R-8:Residential Animal Waste
Animal feces that enters lakes, streams or Puget Sound begins to decay, using up oxygen
and releasing ammonia (nutrients). Low oxygen levels and ammonia combined with warm
water can kill fish. Nutrients encourage weed and algae growth, and contribute to low
oxygen and high pH in waters we use for swimming, boating, and fishing. Most importantly,
feces and fecal contaminated wash water can carry viruses and bacteria that could cause
disease and lead to beach or shellfish harvesting closures.
Best Management Practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of surface water
and stormwater, you will be required to take additional measures.
Supplemental BMPs – Pet Waste
Promptly pick up and dispose of your pet waste when away from home.
Regularly pick up pet waste deposited on your property.
Put pet waste in a securely closed bag and deposit it in the trash. Do not place pet
waste in yard waste containers because pet waste may carry diseases, and
composting may not kill disease-causing organisms.
Do not compost or use pet waste as fertilizer. Harmful bacteria, worms, and
parasites that can transmit disease can live in the soil for years even after the solid
portion of the pet waste has dissolved.
When cleaning out cages and kennels, dispose of wash water down the toilet or a
mop sink. Otherwise, wash directly over lawn areas or make sure the wash water
drains to a vegetated area.
Bathe pets indoors or in a manner that wash water won’t be discharged to storm
drain systems, ditches, or surface waters.
Required BMPs –Goose Waste
If possible, pick up goose waste using shovels, brooms, rakes, power sweepers, and
trash cans. Properly dispose of goose waste in the garbage.
Do not blow, sweep, or wash goose waste into surface waters or stormwater
drainage systems.
Regularly clean goose waste from areas of chronic deposition.
Supplemental BMPs – Pet Pharmaceuticals and Pesticides
Do not dispose of unused pet pharmaceuticals in a toilet or down a sink.
Pet pharmaceuticals can be disposed of at several medicine return drop-boxes
located throughout the county. Refer to www.kingcountysecuremedicinereturn.org
for guidelines and to locate a drop-box near you.
134
Pet pesticides, such as flea prevention, cannot be disposed of at a medicine return
drop-box. Pesticides should be taken to at a local hazardous waste drop-off location.
Refer to www.hazwastehelp.org
for guidelines and to find a drop-off location near
you.
Supplemental BMPs – Goose Waste
Do not feed wild geese or other waterfowl.
Change areas of chronic accumulation of goose waste from goose friendly to goose
resistant. Reduce lawn areas and increase the height of shoreline vegetation (tall
grass, shrubs) as geese are reluctant to walk through tall vegetation.
Geese’s favorite food is new shoots of grass. Let grass grow to six inches or taller.
Stop fertilizing and watering lawn in areas of geese accumulation to reduce the
palatability of the lawn.
Create a natural geese barrier of 20 to 100 feet of herbaceous vegetation at least 3
feet in height to discourage geese. A narrow, winding path through the plantings will
allow for beach access, while preventing geese from having a direct line of sight
through the planted area. Minimize open sight lines for geese to less than 30 feet.
Where space is limited, use one or two rows of shrub plantings combined with a
fence to construct a geese barrier. Fences can be made from woven wire, poultry
netting, plastic netting, plastic snow fencing, mono-filament line, or electrified wire.
Fences should be at least 24 inches tall (3 feet may be better), firmly constructed,
and installed to prevent the geese from walking around the ends. Lower openings
should be no larger than 4 inches from the ground to prevent goslings from walking
under or through the fence.
Construct bank slopes steeper than 4:1 to discourage geese by preventing a clear
view of the bank top and potential predators. Or, separate the beach from the grass
with a few steep steps, which makes the ascent too difficult for most geese.
Plant shrubs or trees along ponds to limit takeoff and landing opportunities.
Scare geese away when they are around. Geese often learn quickly to ignore scare
devices that are not a real physical danger. Vary the use, timing, and location of
tactics. Take advantage of geese being fearful of new objects. Examples of
harassment and scare tactics include:
Dog patrols: Dogs are the method of choice for large open areas. Results are
o
often immediate. After an aggressive initial use (several times a day for one
or two weeks), geese get tired of being harassed and will use adjacent areas
instead. A dog can be tethered to a long lead (which may require relocating
the dog and tether frequently to cover more area), be allowed to chase and
retrieve a decoy thrown over a large flock of geese, or be periodically
released to chase the birds (if this is not against leash laws).
Eyespot Balloons: Large, helium-filled balloons with large eye-like images.
o
Tether balloons on a 20 to 40-foot monofilament line attached to a stake or
heavy object. Locate balloons where they will not tangle with trees or utility
lines.
135
Flags and Streamers: Simple flags from plastic mounted on tall poles or mylar
o
tape to make 6-foot streamers attached to the top of 8-foot-long poles. Flags
and streamers work best in areas where there is steady wind.
Scarecrows: Effective in areas where geese view humans as dangerous
o
predators. For maximum effect, the arms and legs should move in the wind,
use bright colors, and large eyes. Large, blow-up toy snakes are reported to
work as a type of scarecrow.
Canada geese are protected under federal and state law and a hunting license and
open season are required to hunt them. Where lethal control of Canada geese is
necessary outside of hunting seasons, it should be carried out only after the above
nonlethal control techniques have proven unsuccessful and only under permits
issued by the U.S. Fish and Wildlife Service. Currently, the only agency permitted for
lethal removal is the U.S. Department of Agriculture’s Wildlife Services. Lethal
control techniques include legal hunting, shooting out of season by permit, egg
destruction by permit, and euthanasia of adults by government officials.
The Humane Society of the United States’
Maa
http://www.humanesociety.org/assets/pdfs/wild_neighbors/canada_goose_guide.p
df
6–477–
kingcounty.gov/stormwater.
136
R-9:Residential Dock Washing
Improper washing of docks and floats can result in the discharge of dirt, bird feces, soaps
and detergents that can be toxic to aquatic life.
Best Management Practices (BMPs) are required by King County Water Quality Code (KCC
9.12). If the BMPs included here are not enough to prevent contamination of surface water
and stormwater, you will be required to take additional measures.
Required BMPs –Surface Preparation and Spot Cleaning
Use dry methods and equipment (scraping, sweeping, vacuuming) to remove debris,
bird feces and other contaminants prior to cleaning with water to prevent these
pollutants from entering surface water. This will minimize the need for chemical
cleaners. Dispose of debris from the dock as solid waste.
During cleaning activities, if debris, substances, or wash water have the potential to
enter surface waters through drains, temporarily block the drains prior to cleaning
activities.
Hose down the area if necessary and to the extent practicable, collect wash water
and dispose of it properly.
If the dock is paved and the landward area is vegetated, then the wash water
o
does not have to be collected if the water can soak into the ground without
discharging to surface waters or the storm drainage system. However, the
wash water does have to be filtered to trap solid materials before entering
vegetated areas.
If the dock and the landward area are both paved, then use a sump pump,
o
wet vacuum or similar device that enables collection of wash water and
associated solids so they can be disposed of in a sink or toilet for treatment at
your local sewage treatment plant. On-site septic systems should not receive
washwater containing harsh chemicals. The wash water must not go to
surface waters or storm drainage system.
Try spot cleaning with water and a coarse cloth before using soaps or detergents or
washing down an area.
If a cleaner is needed for spot cleaning:
o
Mix it in a bucket and use it to scrub down only the areas that need extra
o
attention.
Try starting with vinegar and baking soda and move to other options as
o
needed. Spot clean using a rag if harsher cleaning products are needed.
Use a mild detergent or soap that is pH neutral. Avoid or minimize the use of
o
petroleum distillates, chlorinated solvents, and ammoniated cleaning agents.
Use degreasers or absorbent material to remove residual grease by hand and
o
do not allow this material to enter surface waters.
137
Keep cleaners in sealed containers and keep cleaner containers closed
o
securely when transporting between the shore and docks.
Properly dispose of wash water.
o
Minimize the scour impact of wash water to any exposed soil at the landward end(s)
of the dock or below the dock. Place a tarp over exposed soil, plant vegetation, or
put berms to contain eroded soil.
Required BMPs –Goose Waste
If possible, pick up goose waste using shovels, brooms, rakes, power sweepers, and
trash cans. Properly dispose of goose waste in the garbage.
Do not blow, sweep, or wash goose waste into surface waters or storm drainage
systems.
Regularly clean goose waste from areas of chronic deposition.
Required BMPs – Dock Washing and Disposal
During cleaning activities, if debris, substances, or wash water could enter surface
waters through drains, then temporarily block the drains and collect all of the wash
water.
To the extent practicable, collect any wash water generated from hosing down or
cleaning dock areas, and dispose ofit properly.
If the dock is paved and the landward area is vegetated, then the wash water
o
does not have to be collected if the water can soak into the ground without
discharging to surface waters or the storm drainage system. However, the
wash water does have to be filtered to trap solid materials before entering
vegetated areas.
If the dock and the landward area are both paved, then use a sump pump,
o
wet vacuum or similar device that enables collection of wash water and
associated solids so they can be disposed of in a sink or toilet for treatment at
your local sewage treatment plant. On-site septic systems should not receive
wash water containing harsh chemicals.The wash water must not go to
surface waters or storm drainage system.
If pressure washing using light pressure. Avoid using excessive pressure, which may
damage the dock or send flakes of paint and other material into the water. If the
surface is painted with lead or other heavy metal-bearing paint (such as chromium
or cadmium), hire a commercial pressure washing service that will collect, test, and
properly dispose of the wash water.
Do not place any debris or substances resulting from cleaning activities in shoreline
areas, riparian areas, or on adjacent land where these substances may erode into
surface waters.
Where treated wood associated with the structure being washed are present, use
non-abrasive methods and tools that, to the maximum extent practicable, minimize
removal of the creosote or treated wood fibers when it removes marine growth
from creosote or any other treated wood.
138
Do not discharge removed marine growth to surface waters.
Do not discharge emulsifiers, dispersants, solvents, or other toxic deleterious
materials to surface waters or storm drainage systems.
Supplemental BMPs- Goose Waste
Do not feed wild geese.
Change areas of chronic accumulation of goose waste from goose friendly to goose
resistant. Reduce lawn areas and increase the height of shoreline vegetation (tall
grass, shrubs) as geese are reluctant to walk through tall vegetation.
Geese’s favorite food is new shoots of grass. Let grass grow to six inches or taller.
Stop fertilizing and watering lawn in areas of geese accumulation to reduce the
palatability of the lawn.
Create a natural geese barrier of 20 to 100 feet of herbaceous vegetation at least 3
feet in height to discourage geese. A narrow, winding path through the plantings will
allow for beach access, while preventing geese from having a direct line of sight
through the planted area. Minimize open sight lines for geese to less than 30 feet.
Where space is limited, use one or two rows of shrub plantings combined with a
fence to construct a geese barrier. Fences should be at least 24 inches tall (3 feet
may be better), firmly constructed, and installed to prevent the geese from walking
around the ends. Lower openings should be no larger than 4 inches from the ground
to prevent goslings from walking under or through the fence.
Construct bank slopes steeper than 4:1 to discourage geese by preventing a clear
view of the bank top and potential predators. Or, separate the beach from the grass
with a few steep steps, which makes the ascent too difficult for most geese.
Plant shrubs or trees near the water’s edge to limit takeoff and landing
opportunities.
Scare geese away when they are around. Geese often learn quickly to ignore scare
devices that are not a real physical danger. Vary the use, timing, and location of
tactics. Examples of harassment and scare tactics include dogs, eyespot balloons,
flags and streamers, and scarecrows.
Canada geese are protected under federal and state law and a hunting license and
open season are required to hunt them. Where lethal control is necessary outside of
hunting seasons, it should be carried out only under permits issued by the U.S. Fish
and Wildlife Service.
The Humane Society of the United States’
Maa
http://www.humanesociety.org/assets/pdfs/wild_neighbors/canada_goose_guide.p
df
206–477–
kingcounty.gov/stormwater.
139
5.0INFORMATION SHEETS
This chapter provides additional information on how to implement best management
practices for certain commercial and residential activities.
Catch Basin Inserts
Containment
Controlling and Collecting Contaminated Runoff
Covering
Disposal
Drainage Maintenance Contractors
Oil/Water Separator
Spill Response and Cleanup Plan
Water Quality Treatment BMPs
140
Catch Basin Inserts
A catch basin insert is a device installed in a catch
basin to provide water quality treatment through
filtration or absorption.
Catch basin inserts fit into existing catch basins
and are configured to remove one or more of the
following contaminants: coarse sediment, oil and
grease, and litter and debris. Some units may be
able to remove dissolved pollutants and pollutants
associated with fine sediments. When selecting an
insert, ensure that your specific pollutant-removal
needs are met. As with any treatment BMP, catch
basin inserts should never be used in place of
source control practices.
: Inserts designed for the removal of oil and grease contain, and
depend on, oil-absorbing media. The Manual (KCSWDM)
requires specific materials/media to be used in catch basin inserts to ensure oils are not re-
released during storm flows. These inserts are appropriate for use in any area in which
vehicles are used, maintained, or stored. Because of the small storage capacity of these
inserts, they are not acceptable as the sole line of defense against actual oil spills in areas
where large amounts of oil could be released. Large amounts of sediment entering the
catch basin significantly reduce the effectiveness and longevity of the oil absorbing media.
Under these conditions, an oil/water separator with a pre-settling chamber may be more
appropriate.
: Inserts designed for sediment removal may be used at construction
sites and in situations where stockpiles or unpaved areas are likely to contribute high
sediment loads. They may also be appropriate for small (low traffic) businesses. They are
not considered a substitute for other source control BMPs.
: Inserts can also be used for the removal of litter and debris, particularly
leaf and tree material.
Design and Maintenance
Unlike most other treatment BMPs, which must be designed and constructed specifically
for your site, catch basin inserts may be purchased directly from a vendor and installed by
the user. While standardized insert units are available, most vendors are able to customize
their systems for your site. Before purchasing a catch basin insert, the following factors
must be considered.
y: The conveyance capacity refers to the amount of water that the
insert can pass without causing flooding. This capacity is equal to the amount of water that
is able to pass through the insert’s treatment area, plus the amount that can pass through
141
the built-in overflow. Over time, the treatment area begins to clog and the total conveyance
capacity is reduced. If maintenance is neglected or if an unusually high amount of sediment
or debris is captured by the insert, the treatment capacity may drop to zero and all of the
water will have to drain through the overflow (routine inspections help prevent this
problem). In order to minimize the chance of flooding, the insert should function as
designed and be able to handle flow from the area draining to the catch basin. The vendor
should be able to tell you what the conveyance capacity is. Don’t allow employees to poke
holes in the insert to drain flooded areas.
: The treatment capacity refers to the amount of
stormwater that the insert unit will pass through its treatment area. The insert unit should
be sized to ensure that most of the water entering the drain inlet is treated even as the
treatment area starts to clog. The ability of the insert to remove pollutants will be reduced
if water is able to seep between the catch basin grate and the edge of the pavement. Ensure
that this gap is sealed. The vendor should provide you with information on how to prevent
this situation and information on the treatment capacity of the system.
: The maximum weight of the insert/filter will be equal to the weight of
the insert/unit when new, plus the weight of the sediment and water trapped in the unit.
Under the most extreme cases, the treatment area of the insert/unit may become
142
completely clogged, and the unit may be full of water when it comes time to service it. It is
essential the maximum weight of the insert be less than what can be lifted by the people or
equipment to be used during maintenance. Before ordering a system, or having a system
customized to your site, be sure the vendor knows how you will be removing the
insert/unit for maintenance.
Maintenance: Since the installation of one or more catch basin inserts represents a long-
term commitment to maintenance, it is important that the unit selected be easy to use and
maintain, and that it is built to last. Be sure to have the vendor provide a complete
demonstration of the product at your site, and if possible, ask to try an insert before
committing to its purchase.
maintenance.
Frequent inspection of the insert is necessary. Actual maintenance will generally consist of
removing the insert from the catch basin, emptying accumulated sediments, cleaning or
replacing the filter media (if applicable), and reinstalling the insert. In most cases these
materials may be disposed of as regular solid waste, however, media used for oil and
grease removal may require special treatment. See the Disposalinformation sheet for more
information.
Maintenance frequency will vary depending on the site and on the amount and type of
pollutant targeted for removal. All units should be inspected every one to two weeks
(except during periods of dry weather), and complete maintenance performed whenever
necessary. The simplest way to determine whether the units need maintenance is to
inspect them during a rainstormand see whether water is exiting the overflow.
When sediment forms a cap over the
Sediment No sediment cap on the
insert media of the insert and/or
Accumulation insert media and its unit.
unit.
Trash and debris accumulate on Trash and debris removed
Trash and Debris
insert unit creating a from insert unit. Runoff
Accumulation
blockage/restriction.freely flows into catch basin.
Media Insert Not Effluent water from media insert has Effluent water is free of oils
Removing Oil a visible sheen.and has no visible sheen.
Catch basin insert is saturated with Effluent water is free of oils
Media Insert Water
water and no longer has the capacity and has no visible sheen
Saturated
to absorb.
Media Insert-Oil Media oil saturated due to petroleum Effluent water is free of oils
Saturated spill that drains into catch basin. and has no visible sheen
Media Insert Use Media has been used beyond the Effluent water is free of oils
Beyond Normal typical average life of media insert and has no visible sheen
Product Lifeproduct.
143
Additional Information
–
(206) 263-3000
www.kingcounty.gov/environment/wastewater/IndustrialWaste
(206) 263-8899
www.hazwastehelp.org
www.kingcounty.gov/swdm
–477–
kingcounty.gov/stormwater.
144
Containment
Containment refers to methods to prevent material from leaving or entering a specific area.
Containment is an effective means for preventing uncontaminated stormwater from
flowinginto or onto a contaminated activity area. It is also critical for containing spills in
activity areas where pollutants may be present.
The term “” means the
specific requirement for all chemical liquids, fluids,
petroleum products and hazardous wastes stored
on-site, to be in a containment area sized to hold a
volume of 110 percent of the volume of the largest
container or 10% of the volume of all the containers,
whichever is greater. Secondary containment may
be achieved with specially designed containment
pallets, concrete curbing, or earthen berms,
depending on the nature and amount of the
material, activities on-site, and site-specific
conditions.
Use separate secondary containers for
products and wastes that are incompatible
(e.g., acids and bases).
Make sure the construction materials and
containers are compatible with products or
wastes stored.
Activity areas contained by a curb, berm, or dike (to prevent stormwater run-on) should be
covered. This will stop precipitation from ponding inside the secondary containment area.
In some instances, run-on prevention can be accomplished by placing a curb or berm on the
upslope sides of the area. Elevating the activity or storing materials on a platform can also
prevent stormwater run-on.
If not covered, containment areas will allow rainwater to
accumulate. Contaminated water cannot be drained from the
containment area to storm drains or surface waters, or
infiltrated into the ground. The water must be collected and
disposed of either in a sanitary sewer, a stormwater
treatment system, or at a licensed decant facility. During the
wet season, secondary containment without cover can lead
to frequent disposal of relatively clean water that can be
costly. For more detailed information on uncovered
containment areas, see the Controlling and Collecting
Contaminated Runoff information sheet.
145
If containing stockpiles of erodible material, a dike, berm, or filtering device must be placed
on at least three sides to act as a barrier or filter to treat runoff and to remove suspended
solids. If the containment device is three-sided, the open side should not be on the upslope
or the downslope side of the stockpile. The dike or filter can be made of hay bales, silt
fencing (filter fabric), concrete curbing, ecology blocks, compacted earth with grass planted
on it, or similarly effective materials. Timbers treated with creosote or other preservatives
should not be used because they can leach contaminants into runoff. All filter materials
used around stockpiles must be maintained to work effectively and must be replaced when
necessary. See Appendix D of the Surface Water Design Manual for other options.
For storing small items, a tub or wading pool is an
acceptable containment structure. A rubber or
plastic wading pool may be sufficient for
containment of some stored materials that do not
require much space, such as storing remodeling or
painting materials, or temporary storage of wastes
in drums.
(uncovered)
These small storage devices should also be covered to prevent rain from accumulating. You
must also consider the type of materials stored to ensure adverse chemical reactions do not
occur with the containment material.
Regular maintenance of containment devices
is essential for proper functioning.
Commercial products are available that
combine containment boxes with elevated
pedestals. They prevent stormwater run-on
by elevating containers of liquids off the
ground and collecting spills and drips inside
the pedestal box.
Additional Information
The name and phone number are identified on your water and sewer bill.
–
(206) 263-3000
www.kingcounty.gov/environment/wastewater/IndustrialWaste
(206) 263-8899
www.hazwastehelp.org
146
(206) 477-4811
www.kingcounty.gov/stormwater
www.kingcounty.gov/swdm
–477–
kingcounty.gov/stormwater.
147
Controlling and Collecting Contaminated Runoff
This BMP applies to activities that cannot be covered effectively yet require a method of
controlling and containing contaminated runoff. It is particularly suited to activities with
the potential for spills and leaks, but that otherwise do not generate excessive amounts of
polluted runoff or that are intermittent such as washing or cleaning operations. A sump or
holding tank can provide containment until the liquids can be pumped out of the tank and
disposed of properly. If the activity produces large amounts of runoff or wastewater, this
BMP will not be effective because contaminated water will overflow the sump or pass
through the sump before collection and disposal are possible. A designated area must be
paved and sloped to a drain connected to a central collection point. A sump, vault, or
holding tank must be installed to capture the wastewater. Some materials, such as gasoline,
can react with and cause deterioration of asphalt pavement. It is preferable for the area to
be paved with Portland cement concrete. If the area is already paved with asphalt, an
asphalt sealant should be applied to the pavement surface. Whatever material is used, the
paved surface must be free of gaps and cracks.
The sump or holding tank should have
a large enough capacity to contain the
entire volume of wastewater or
potential spill generated by the
activity. Depending on the
circumstances, the sump or tank can
be equipped with an outflow pipe to
allow discharge of uncontaminated
runoff to the storm drainage system,
along with a shutoff valve to prevent
outflows in the case of a spill. The local sewer authority may, in some instances, allow a
connection to the sanitary sewer system.
The paved activity area must also be
contained to prevent stormwater run-
on and runoff. Curbs, dikes, or berms
direct uncontaminated runoff away
from the area so that only the
precipitation falling within the activity
area is discharged (and/or treated)
along with the process water. See the
Containment information sheet for
more information.
The catch basin/tank/sump must have a two-way valve installed at the outflow pipe so that
uncontaminated runoff can flow to the storm drainage system when the pollutant-
generating activity is not occurring. The two-way valve must easily switch between
discharges to the sanitary sewer, holding tank, or treatment facility, and discharges to the
storm drainage system. When the activity is occurring, the two-way valve must be set so
148
the polluted runoff discharges to the sanitary sewer, holding tank, or treatment system.
After the pollutant-generating activity operation is finished and no more process water is
generated, the area must be washed down so that the wash water discharges to the
sanitary sewer, holding tank, or treatment facility. The two-way valve must be switched
after clean-up is completed so that subsequent runoff is discharged to the storm drainage
system until the activity resumes. It is critical this valve is always switched to the correct
position. Just as contaminated stormwater cannot be discharged to the storm drain
system, uncontaminated stormwater cannot be discharged to the sanitary sewer.
Approval for discharges with a two-
way valve should be obtained from
the King County Industrial Waste
Program, the local sewer authority
and King County Water and Land
Resources Division, Water Quality
Compliance Unit.
If discharges to the storm drainage system or sanitary sewer are not allowed, the sump or
holding tank contents must be pumped out periodically and disposed of properly. This
requirement can make this BMP costly, especially during the wet season. See the Disposal
information sheet for disposal options. To keep disposal costs down, use a drain cover,
plug, or shutoff valve in the pipe leading to the sump when the activity is not occurring.
Before starting the activity (if the activity is intermittent), open the cover, plug, or valve.
Constructing a sump and disposing of
accumulated contents can be
expensive, so businesses should
consider other BMP alternatives.
Your local sewer agency may charge
additional fees for a sanitary sewer
hookup. The fees depend on location,
quantity of discharge, and whether
the hookup is for a business or
residence. A King County industrial
waste discharge permit may also be
required.
Several commercial services are available for pumping out sumps and holding tanks.
Information on these services can be found on the King County Stormwater Services
website at www.kingcounty.gov/stormwater and the Drainage Maintenance Contractors
information sheet. Septage hauling contractors may not be used for this type of service.
149
Additional Information
The name and phone number are identified on your water and sewer bill.
–
(206) 263-3000
www.kingcounty.gov/environment/wastewater/IndustrialWaste
(206) 263-8899
www.hazwastehelp.org
(206) 477-4811
www.kingcounty.gov/stormwater
www.kingcounty.gov/swdm
–477–
kingcounty.gov/stormwater.
150
Covering
Covering potential pollutant-generating activities and materials is one of themost effective
ways to prevent stormwater contamination. All of the options must be combined with a
method to prevent run-on of stormwater into piles and runoff of any liquids that might
leave the pile. See the Containment
information sheet for more information.
The first step is reviewing what materials are stored outside and what activities are
conducted outside that could cause pollutants to get on the ground.
1. Does the activity need to be conducted outside? Does the material need to be stored
outside? Is there a suitable indoor location for these activities?
2.How often does the activity occur?
3.How often is the material used?
4. Can any of the material or equipment be removed if it is no longer needed?
5.Is it feasible to tarp materials or is a permanent structure needed?
Tarps
Many materials, such as stockpiles of erodible materials or
storage of drums, can be by covered with a heavy plastic
tarp made of impermeable material. Weights such as bricks,
tires, or sandbags must be used to anchor the cover in place.
Care should be taken to ensure that the tarp covers the
stored materials completely and that stormwater does not
penetrate the cover. If several tarps are used to form a cover,
they should be tethered together or overlapped. If necessary,
Tarp
pins or stakes should be used to anchor the tarps to the
ground. The tarp/cover will be easier to keep in place and
will last longer if some form of wind protection is used or stockpiles are located in areas
protected from the wind. The tarps must be in place when the material is not being used
and inspected weekly to ensure that no holes or gaps are present.
Roofs & Awnings
The other option for covering is a roof.
The roof cover option used depends on
the site layout, available space,
affordability, and limitations imposed
by other regulations. The area of the
roof should be sufficient to keep the
contents underneath dry. The
storage/activity area must be designed
to prevent stormwater run-on into the
covered area.
Lean-
151
Permanent structures may require a permit and must
comply with all applicable building and fire codes.
Contact the King County Department of Permitting and
Environmental Review for information on permits and
code requirements for a roof structure.
Stand-
Another option for covering is to use an overhanging
awning large enough to prevent precipitation from
reaching the contents underneath. This does not include
awnings already in place over a public right-of-way such as
a sidewalk in front of a store, as this area is not suitable for
storage or business activities. Many of the building permit,
fire code, and zoning code requirements mentioned above
apply to these structures.
Storage Sheds
There are also numerous prefabricated storage sheds that may be effective. Before
purchasing these structures, ensure they meet applicable building and fire codes.
Fueling Operations
Activities such as fueling operations must covered
by an island-type roof. This roof is supported by
columns along the center of the structure rather
than at the corners, allowing vehicular traffic
underneath while still providing protection from
precipitation. Refer to BMP Activity Sheet A-17:
Stationary Fueling Operations for requirements.
Island-
Additional Information
en
Land Use, Fire Code, and Building Code Requirements
(206) 296-6600
www.kingcounty.gov/property/permits
(206) 477-4811
www.kingcounty.gov/stormwater
www.kingcounty.gov/swdm
ou–477–
kingcounty.gov/stormwater.
152
Disposal
All solid and liquid wastes and contaminated stormwater in King County must be disposed
of properly. There are generally five options for disposal depending on the types and
quantity of materials. These options are:
1. Sanitary sewer system
2. Septic system
3. Municipal solid waste disposal facilities
4. Recycling
5. Off-site waste transportation and disposal services.
Ordinary stormwater runoff is not considered to be contaminated, but stormwater that is
mixed with concentrated wastes requires special disposal, as discussed below.
Discharge to Sanitary Sewer System
Wastewater generated by commercial and industrial processes (depending on the nature of
the wastewater) may be put into the sanitary sewer, subject to approval by the local sewer
authority and the King County Industrial Waste Program. It may be necessary to pretreat
the wastewater in order to remove pollutants. Sewer fees may be collected on such
discharges. The local sewer authority and King County must be contacted prior to the
installation of any permanent connection to the sanitary sewer.
Process wastewater may be recycled on-site as an alternative to discharge to the sanitary
sewer. There are numerous products on the market that are designed to recycle wash
water.
It is not an option to discharge stormwater to the sanitary sewer in place of implementing
adequate best management practices to prevent contamination.
Contact your local sewer agency for information on allowable discharges and the
location of your side sewer. The name of your local sewer agency is identified on your
water and sewer bill.
–
The Industrial Waste Program provides information on what can be discharged to the
sanitary sewer. Industrial Waste can also assist with information regarding the
rerouting of illicit storm water connections/discharges.
(206) 263-3000,www.kingcounty.gov/environment/wastewater/IndustrialWaste
Discharge to Septic System
If your site is not serviced by a sanitary sewer system, you probably have a septic system.
Only waste that is comparable to residential sewage may be disposed of into septic
systems. Hazardous chemicals and process wastewater cannot be disposed of into septic
153
systems. Furthermore, the septic system must be designed to accommodate the volume of
wastewater generated. Any changes in waste volume and constituency from those which
existed when the system was permitted must be approved by Public Health – Seattle & King
County. Stormwater, whether contaminated or not, may not be disposed of in septic
systems. Animal waste may not be disposed of in a septic system unless specifically
designed for this purpose.
-–
Information regarding on-site sewage treatment systems (septic systems) is available
for both property owners and septic system professionals.
(206) 296-4932 , www.kingcounty.gov/healthservices/health/ehs/wastewater.aspx
Municipal Solid Waste Disposal Facilities
Municipal solid waste disposal facilities are designed to handle solid wastes. They do not
accept liquid wastes. Hazardous and dangerous wastes and many liquid wastes must be
properly transported and disposed of at an appropriate offsite facility. Contact your local
solid waste disposal facility or contact King County Solid Waste Division to find out how to
dispose of garbage and other materials.
The Solid Waste Division (SWD) provides garbage transfer, disposal and recycling
services for residents and businesses in all of King County, except for Seattle and Milton.
SWD also provides household hazardous waste disposal options and recycling
education programs for its residents.
(206) 477-4466, www.kingcounty.gov/solidwaste/index.asp
The Business Waste Line answers questions from small businesses on the proper
disposal of oil, antifreeze, and other hazardous wastes. The Waste Line may also be
used to report complaints and hazardous waste violations.
(206) 263-8899 , www.hazwastehelp.org
The Onsite Consultation Program provides free visits to businesses that request
assistance with hazardous waste handling and waste reduction. Only small quantity
generators of hazardous wastes (or businesses that are potentially small quantity
generators) qualify for this service.
206-263-8899, www.hazwastehelp.org
Recycling
Recycling facilities are recommended for many commercial items, including used oils, used
batteries, a variety of used auto parts, scrap metal, solvents, paints,and other solid wastes.
There are a number of private businesses that accept materials for recycling. There is also
an Industrial Material Exchange clearinghouse which facilitates the transfer of unwanted
materials from the generator to another business that can use them.
154
–
This program assists businesses with recycling by: 1) providing information on waste
reduction and recycling services for particular needs; 2) helping you work with your
employees to promote participation; 3) offering information on buying recycled
products; and 4) providing you with ongoing support to ensure your program is
successful.
(206) 477-4466, http://your.kingcounty.gov/solidwaste/business/index.asp
IMEX provides a free service helping businesses with surplus materials to find
businesses that need them. Surplus or waste materials, such as solvents, paint, plastics,
and wood, are exchanged. The website lists materials available and materials wanted.
IMEX is a component of the Hazardous Waste Management Program.
(206) 263-8465 , www.lhwmp.org/home/IMEX/index.aspx
Offsite Waste Transportation and Disposal Services
Depending on the nature of the waste, it may not be possible to dispose of it in the sewer or
municipal landfill. The Seattle-King County Department of Public Health’s Waste
Characterization Program serves hazardous waste generators in Seattle and King County.
Information supplied by the generator on questionable wastes such as sludge, sandblast
waste, treated wood, and contaminated soils is reviewed by the Health Department.
Permits are issuedfor wastes that will be allowed in the garbage. The State of Washington’s
dangerous waste regulations as well as other criteria are used in the decision process.
Sumps, holding tanks or other temporary storage devices may be useful for storing
relatively small volumes of liquid wastes on a temporary basis if you cannot discharge to a
sanitary sewer or septic system. There are commercial services that can help you identify,
quantify, transport, and dispose of any waste that you may generate. They can pump out
your sump or holding tank and haul the waste to authorized disposal locations. These can
be found in the yellow pages under the headings “Sewer Contractors and Cleaners” and
“Tank Cleaning,” or on the King County Stormwater Services website at
www.kingcounty.gov/stormwater. Holding tanks must be pumped out or drained before
the tank is full. Septic system pump out and hauling contractors may only dispose of
domestic sewage and cannot haul industrial wastes.
Costs of disposal vary considerably depending on the types of materials, quantities,
methods of collection and transport, and whether the wastes are mixed. The rate the
contractor charges will generally reflect the costs of testing and/or treating waste
materials (if necessary) and the subsequent disposal. It is important to keep different types
of wastes separated, so that the disposal contractors can take them to the appropriate place
without causing inadvertent contamination problems elsewhere, and so that you are not
paying too much for disposal of materials that are not contaminated (e.g. regular garbage).
It is essential to be familiar with disposal alternatives and the different types of contractors
for each disposal option so that all wastes are disposed of properly.
155
The disposal of wastes is the responsibility of the generator. Before agreeing to let a
company handle your waste, it is recommended that you check the company's references.
All waste collected by the company should be delivered to an authorized site. Transfer of
waste to a vendor does not release a generator from legal obligation for disposal to a
licensed disposal facility. Generators of wastes to be hauled off-site should keep copies of
all transactions, including waste manifests and receipts.
---
(206) 263-8528
www.kingcounty.gov/healthservices/health/ehs/toxic/SolidWaste.aspx
The Department of Ecology is the source of information on businesses that provide
dangerous waste treatment, storage, and disposal (TSD) services, and information on
applicable regulations for TSD businesses.
www.ecy.wa.gov/programs/hwtr/managewaste.html
–477–
kingcounty.gov/stormwater.
156
Drainage Maintenance Contractors
The firms below perform drainage system cleaning and maintenance services. King County
provides this list for your convenience but makes no recommendation whatsoever
regarding these firms.
A--N-
P.O. Box 84523 18912 SE 133rd Place
Seattle, WA 98134 Renton, WA 98059
Phone: 206-749-5700 or 1-800-343-8096 Phone: 425-271-5459 or
Fax: 1-800-659-3624 1-800-84-CLEAN
Fax: 425-227-9793
www.aquacleanjetnvac.com
PO Box 1270
Maple Valley, WA 98038
425-890-1214-Troy 206-719-1509-Joey P.O. Box 159
Fax: 425-392-0694 Sumner, WA 98390
cainspw@hotmail.com Phone: 1-888-851-2378 or 1-800-310-
7406
ACTION
Emergency: 253-221-1018
PO Box 4339 Fax: 253-770-0724
Bremerton, WA 98310
www.bestparkinglot.com
Phone: 360-373-4265 or 1-800-697-1000
Fax: 360-373-9711
6009 212th St. SW
amy@getasc.com
Lynwood, WA 98036
Phone: 425-778-2557 Emergency: 206-
510-5482
8463 South 212th St. Fax: 425-672-2434
Kent, WA 98031 www.bodineconstruction.com
Phone: 253-872-9363 or 1-800-275-3549
Fax: 253-872-0260
www.shopaes.com 6437 S. 144th St.
Tukwila, WA 98168
Phone: 425-424-9000
Pacific NW Regional Offices: Fax: 425-424-9002
10220 North Nevada, Suite 70 www.bravoenvironmental.com
Spokane, WA 99218
Phone: 509-922-4973
Fax: 509-922-1783 2522 North Proctor St., Suite 370
www.apexcos.com Tacoma, WA 98406
Phone: 253-572-0989
Cell: 253 279-5110
www.catchallenvironmental.com
157
55 InternationalWay 5111 85th Ave. East, C-2
Longview, WA 98632 (works in King Puyallup, WA 98371
County) Phone: 253-255-5663
Phone: 888-423-6316 Fax: 253-926-5555
Fax: 360-423-3409 www.drainproinc.com
www.pnecorp.com
9620 South 242nd Court
2103 East 112th St. Kent, WA 98030
Tacoma, WA 98445 Phone: 253-236-5000
Phone: 253-536-5500 or 1-800-290-3008 Fax: 253-277-0794
Fax: 253-536-5900
www.certifiedcleaning.com
7343 East Marginal Way South
Seattle, WA 98108
Phone: 206-832-3000 or 206-832-3052
26328 79thAve. South Fax: 206-832-3030
www.emeraldservices.com
Kent, WA 98032
Phone: 253-639-4240
Fax: 253-639-4249
www.cleanharbors.com
6825 216th St SW
Lynnwood, WA 98036
PO Box 46876
Phone: 425-673-2900
Seattle, WA 98146 Fax: 425-673-7511
Phone: 206-242-7280
Fax: 206-257-1529
drainagesystems@gmail.com
P.O. Box 259
Lake Stevens, WA 98258
12020 SE 32nd St., Suite 4 Phone: 206-622-7070 or 1-800-433-1678
Bellevue, WA 98005 www.evergreensanitation.com
Phone: 425-289-1145 or 1-866-457-9337
Fax: 425-289-1146
www.davidsonmacri.com P.O. Box 428
Sumner, WA 98390
Phone: 253-848-5250
13122 NE David Circle Fax: 253-848-5363
Portland, OR 97230 www.eversons-econovac.com
Phone: 503-542-0906
Fax: 503-542-0908
www.dbiservices.com
158
M
1115 NW 51st St.
Seattle, WA 98107 4004 103rd Ave. SE
Phone: 206-337-2141 Lake Stevens, WA 98258
Fax: 206-784-4924 Phone: 425-377-9820
www.fischerplumbing.com Fax: 425-377-9830
1813 99th St. East PO Box 440
Tacoma, WA 98445 Kapowsin, WA 983454
Phone: 253-536-0455 Phone: 253-875-0074
Fax: 253-536-3072 Fax: 360-893-1091
www.guardianindustrial.net Emergency: 253-377-3007
www.rickysstormdraincleaning.com
20909 70th Ave. West
27218 SE Kent Kangley Rd.
Edmonds, WA 98026
Phone: 206-783-3317 or 1-800-945-4081 Ravensdale, WA 98051
Fax: 206-783-9109 Phone: 425-432-1054
www.innovac.comwww.msisweep.com
1501 NW 46th St. P.O. Box 73399
SEATTLE WA 98107 Puyallup, WA 98373
Phone: 206-633-1141 or 425-454-8153 Phone: 253-838-2359 or
Fax: 206-784-2095 1-800-562-4442
www.jimdandysewer.comwww.nwcascade.com
P.O. Box 3028 P.O. Box 52985
Federal Way, WA 98063 Bellevue, WA 98015
Phone: 253-815-0988 Phone: 206-271-2776
Fax: 253-815-0325 Fax: 425-222-4843
office@lavellvac.com www.nwnatives.com
PO Box 24263
Seattle, WA 98124 1621 Central Ave. South
Phone: 206-762-0240 or 1-800-540-7491 Kent, WA 98032
Fax: 206-763-8084 Phone: 206-480-2072 -South End
www.marinevacuum.com Phone: 206-851-4869 -Seattle
Fax: 253-480-2073
www.nwstormwater.com
159
9520 10th Ave. South Suite 150 4008 132nd Pl. NE Suite 502
Seattle, WA 98108 Marysville, WA 98271
Phone 1-800-337-7455 or 206-607-3000 Phone: 425-487-6313
Fax: 206-607-3001 Fax: 425-487-6413
www.nrces.com www.reliakor.com
-
6622 112th St East 175A Roy Rd. SW, Suite 101
Puyallup, WA 98373 Pacific, WA 98047
Phone: 253-435-4328 Phone: 253-872-6970
Fax: 253-435-5788 Fax: 253-872-2390
Cell: 253-606-4212 www.rescuerooter.com
dean@pro-vac.com
3102 B St NW
26220 79th Ave. South
Auburn, WA 98001
Kent, WA 98032 Phone: 253-561-8270
Phone: 253-856-2572 Fax: 253-939-5051
Fax: 253-859-5087 www.safety-kleen.com
www.pcsjac.com
1820 North 48th St.
2212 Port of Tacoma Rd. Seattle, WA 98103
Tacoma, WA 98421 Phone: 206-632-8069
Phone: 253-661-0828 www.seattledrainservice.com
Fax: 253-952-7465
PRO-14221 29th St. East, Suite 101
Sumner, WA 98390
6622 112th St. East
Puyallup, WA 98373 Phone: 253-863-3310
Phone: 253-435-4328 or 1-888-565-5665 Fax: 253-863-3490
Fax: 253-435-5788 www.thermofluids.com
www.pro-vac.com
18000 72nd Ave. South 12201 Avondale Rd. NE
Kent, WA 98032 Redmond, WA 98052
Phone: 1-800-882-9785 or 425-227-0311 Phone: 425-558-4437
Emergency: 1-877-577-2669 Fax: 425-869-2633
Fax: 425-204-7164 david@tigerexcavation.com
www.pscnow.com jill@tigerexcavation.com
160
3914 Leary Way NW
Seattle, WA 98107
Phone: 1-800-347-3509 or 206-634-2750
Fax: 206-634-2753
www.ventilationpower.com
6801 – 216th St SW
Mountlake Terrace, WA 98043
Phone: 425-697-4373 or 1-800-800-2935
www.whirlwindservices.com
Sound
2811 Fairview Ave East, Suite 2000
Seattle, Washington 98102
Phone: 206-306-1900
Mobile: 206-462-0380
Visit King County StormwaterServices Drainage System Maintenance Contractors
webpage, https://kingcounty.gov/services/environment/water-and-
land/stormwater/problem-investigation-line/drainage_maint_vendors.aspx for the most
current list of drainage maintenance contractors.
–477–
kingcounty.gov/stormwater.
161
Oil/Water Separator
APPLICATION AND DESCRIPTION
An oil/water separator is a device designed to
remove oil, grease, and similar floatable
pollutants from stormwater runoff. The name
commonly refers to an underground structure;
however, more simple designs exist.
Oil/water separators are appropriate at
locations where petroleum products may be
difficult to control with source-control BMPs.
An oil/water separator can be a tee section in
a catch basin that contains spills on an
emergency basis, or a complex unit that is
designed to treat runoff from sites.
For many sites, such as small parking lots, a simple
down-turned elbow in a catch basin will temporarily
contain pollutants, so they can be cleaned up a
before leaving the site. If tee sections are used or
installed in catch basins, other measures must be
used such as oil absorbent pads or booms. On-sites
with greater potential for oil spills and high
concentrations of oil and grease in runoff, such as
fleet vehicle lots, auto repair shops, or fueling
stations, a more complexoil/water separator is
needed. Spills must always be cleaned up
immediately to avoid downstream contamination.
There are two types of complex oil/water separators
commonly used in situations where oily runoff is a concern: the American Petroleum
Institute (API) separator and the coalescing plate interceptor (CPI). The API separator has
the appearance of a long septic tank and must be sized relative to the area it is treating. By
placing coalescing plates in the separator, its size can be significantly reduced while
retaining the efficiency needed. Consequently, the CPI separator is more commonly used.
The savings from reducing the cost of vault construction offset the relatively high cost of
the plates.
These oil/water separators should be used for targeted pollutant removal in high traffic
areas where oil or petroleum products are a significant problem rather than as an all-
purpose stormwater treatment facility. The separator will function more efficiently and
require less maintenance if the amount of stormwater passing through is limited. Only
runoff that has been exposed to high oil activity areas should be directed through the
oil/water separator. Avoid directing stormwater (from other areas on your site) through
the separator.
162
For information on oil/water separators that will be used as pretreatment prior to
discharge to the sanitary sewer, contact your local sewer agency or King County’s
Industrial Waste Program within the Wastewater Treatment Division.
DESIGN AND MAINTENANCE
API and CPI oil/water separators must be designed and sized in accordance with the
. Oil/water separators must be checked frequently
during the wet season. These inspections must occur often enough to prevent BMP failure
that allows waste products to exit the oil/water separators. Violations can be cited under
King County Code 9.12. How often material should be removed depends on the amount of
petroleum in the influent, but the separator should be cleaned at least quarterly, and
particularly in the fall before the first storm of the wet season. In addition, the following
maintenance requirements apply:
Remove all sediments from the unit or catch basin if greater than six inches in
depth, or if within six inches of the outlet pipe. Sediments should be tested and
disposed of properly.
Oil absorbent pads should be replaced as needed, but should always be replaced in
the fall prior to the wet season, and in the spring. Collect used pads in a covered
container for oil recovery and recycling by a vendor.
Use a vendor to clean out the oil/water separator and take any oil and residuals to
an approved offsite location for disposal and/or recycling.
The outlet pipe of the separator must be blocked during cleaning operations.
Any standing water removed during the maintenance operation must be disposed to
a sanitary sewer at a discharge location approved by the local jurisdiction.
Additional Information
The name and phone number are identified on your water and sewer bill.
K–
(206) 263-3000
www.kingcounty.gov/environment/wastewater/IndustrialWaste
(206) 263-8899
www.hazwastehelp.org
www.kingcounty.gov/swdm
–477–
kingcounty.gov/stormwater.
163
Spill Response and Cleanup Plan
It is critical to have your employees trained, and have a plan and supplies in place to
address spills that might occur on or near your property. A spill plan identifies the
materials of concern and outlines the steps to be taken when responding to a spill. Plans
are customized to each site and can be prepared in-house or by consultants. A template for
a sample spill plan follows. There are numerous resources and templates for spill
prevention and clean-up plans that can be found online.
The nature of the business, the type and amount of liquid materials transferred and stored
on-site, and the potential for spills will dictate the scope and detail of a spill plan. It is
critical that the plan be kept up to date to reflect personnel and procedural changes and to
have a regular, ongoing review of the plan by all affected employees.
Spill plans should include the following elements:
Identification of materials of concern
Spill prevention methods (if you don’t have a site pollution prevention plan)
Likely areas for spill or leaks to occur
Site plan that identifies the locations of liquid material storage and spill control
equipment
Spill control techniques
Evacuation procedures (if necessary)
Cleanup procedures
Designated responsible employees
Spill reporting protocols
Emergency contact numbers
Even if unsure whether a spill presents a threat tohuman health, welfare, or the
environment, go ahead and report it. This will ensure that you have complied with state
and federal spill reporting laws. The sooner the agencies know about an incident, the
quicker they can deploy resources and assistance to reduce damage to the environment
and protect natural resources.
A downloadable version of the spill response and clean-up plan is available at
www.kingcounty.gov/stormwater
–477–
kingcounty.gov/stormwater.
164
SPILL RESPONSE AND CLEANUP PL AN
Company Name Date
Site Address Runoff Drains to
FACILITY ACTIVITIES (Check all that apply)
䢿
Loading/unloading of products
Fueling & fuel transfer
䢿
Landscapeconstruction/maintenance
Outdoor manufacturing
䢿
Outside storage of uncovered materials
Outside drum or container storage
䢿
Other:
Vehicle, equipment & building washing
LIQUIDS STORED ONSITE (Check all that apply)
Cleaning Products Solvents & Paints Petrochemicals
Solvents, degreasers
Bleach Antifreeze
Paint thinner, turpentine
Drain cleaners Brake and transmission fluid
Paints, coatings, sealers
Sanitizers Gasoline
Preservatives
SoapsOil (motor, cutting)
Other liquids
Other Hydraulic fluids
Food Preparation/Waste Acids, Bases, Chemicals Other
Cooking Oil Acid Fertilizers
Grease Ammonia Inks, dyes
Other liquids Caustic, base, lye Other liquids
Photographic chemicals Pesticides, herbicides
165
SPILL RESPONSE AND CLEANUP PL AN, CONTINUED
CONTACTS
TitleNamePhoneNumbers
Site Manager
EnvironmentalOfficer
Onsite Spill Cleanup Coordinator
Backup Spill Cleanup Coordinator
Business Owner
Cleanup Contractor
Potential Spill Areas (list all locations)
Spill Material & Spill Kit Locations (list all locations)
Attach a SitePlan
166
SPILL RESPONSE AND CLEANUP PL AN, CONTINUED
ADDITIONAL INFORMATION
Provideadescriptionofanyadditionalemergencycleanupanddisposalproceduresnotlisted
above that you will use at your site, or any other special conditions that exist:
167
SPILL RESPONSE AND CLEANUP PL AN, CONTINUED
SPILL REPORTING
Stop,contain,andcleanupthechemicalspillif:
The spilled chemical and its hazardous properties have been identified;
The spill is small and easily contained; and
The responder is aware of the chemical’s hazardous properties.
Spill clean up
Alert the manager/owner of property where the spill has occurred.
Obtainpersonalprotectiveequipment,asappropriatetothehazards.RefertotheMaterialSafetyData
Sheet or other references for information.
Stopthesourceofthespill(uprightcontainer,plugleak,etc.).
Seal off storm drains with berms or drain covers and stop any spread of the spill.
Protect floor drains or other means for environmental release. Spill socks and absorbents may be placed
around drains, as needed.
Use pads and/or granular sorbent to clean up spilled material. Loose spill–control material should be
distributed over the entire spill area, working from the outside, circling to the inside. When spilled materials
have been absorbed, use brush and scoop to place materials in an appropriate container.
Let pads sit on spill to absorb spilled material.
Remove spent pads and/or sorbent and dispose of properly.
If a spill or release cannot be controlled or injuries have occurred due to the release the following
procedures should be implemented:
Summon help or alert others of the release;
Evacuate the immediate area and provide care to the injured – Call 911;
If potential fire or explosion hazards exist, initiate evacuation procedures – Call 911;
Respond defensively to any uncontrolled spills:
Use appropriate personal protective equipment when responding to any spill;
Attempt to shut off the source of the release (if safe to do so);
Eliminate sources of ignition (if safe to do so);
Protect drains by use of adsorbent, booms or drain covers (if safe to do so).
Notify the onsite emergency contacts;
Notify other trained staff and/or emergency response contractors to assist with the spill response and
cleanup activities;
Be prepared to provide MSDS information to the fire department, EMT, hospital or physician;
Notify the appropriate agency if a release has entered the environment. Refer to the Spill Reporting Table
for reporting thresholds.
168
SPILL RESPONSE AND CLEANUP PL AN, CONTINUED
SPILLREPORTING
Ecology Northwest Regional Office:
spill of hazardous material, oil, or otherImmediately,butno
A
substance, unless there is no chance it later than 24–hours
206-594–0000
after obtaining the
will leak out of the building, get into a
knowledge.
storm or sewer drain or endanger people.
Ecology Northwest Regional Office:
A spill or discharge which could Immediately, but no
constitute a threat to human health, later than 24–hours
206-594–0000
welfare, or the environment. after obtaining the
AND
911
knowledge.
National Response Center:
A spill or discharge of oil or hazardous Immediately
substances which presents a threat
1-800-424–8802
to human or health, welfare, or the
AND
Washington Emergency
environment.
Management Division:
1–800–
258–5990 OR 1–800–OILS911
AND
Ecology Northwest Regional Office:
206-594–0000
AND
911
WA State Department of Health:
A spill or discharge which might cause Immediately
bacterial contamination of shellfish. 360-236–3330
AND
Ecology Northwest Regional Office:
206-594–0000
King County Stormwater Services:
All spills to the storm drain system, Immediately
including catch basins and drainage
206-477–4811
ditches, as well as streams, lakes, etc.
To the best of your ability, please be ready with the following information:
Where is the spill?
What spilled?
How much spilled?
How concentrated is the spilled material?
Who spilled the material? Is anyone cleaning up the spill?
Are there resource damages (e.g. dead fish or oiled birds)?
Who is reporting the spill?
How can we get back to you?
169
Water Quality Treatment BMPs
Water quality treatment BMP options may be required if operational or basic structural
source controls do not adequately address pollutant discharges from your site. Source
control BMPs, as presented in Chapter Three, must always be implemented before
treatment BMPs are considered.
The following information describes some basics of water quality treatment
systems/facilities. Design and construction details can be found in the
(which contains relevant information for the treatment BMPs
discussed). A private vendor specializing in the treatment system or an engineering
consultant can also provide information on treatment systems. All of these systems require
regular inspection and maintenance in order to function properly.
Businesses and agencies are allowed to select a treatment BMP other than those presented
in this manual if they follow the adjustment process as outlined in the
Wa and obtain approval from the King County Water Quality Compliance
Unit.
The first table presents a brief description of some typical water quality treatment BMPs.
The second table presents water quality treatment BMPs for removing specified pollutants.
One treatment BMP usually cannot treat all pollutant problems. Each BMP is designed for a
specific purpose and is capable of removing only specified pollutants. If you decide to
install a water quality treatment BMP, always ensure that it is removing the pollutant of
concern from your site runoff.
206–477–
kingcounty.gov/stormwater.
170
An underground vault specifically designed to remove oil and
Oil/Water Separator
grease. Also, will remove floatable and some settleable solids.
A filtering device that is installed within an existing catch basin
and uses various sorbent materials and settling space to collect
Catch Basin Insert
pollutants.
Catch Basin Sump and A device similar to catch basin inserts, only larger and placed
Vault Filter underground.
A filtering device that is installed above or below ground and
Leaf Compost Filters
uses leaf compost to remove pollutants from stormwater.
A wet pond is a stormwater pond that retains a permanent pool
of water. A constructed wetland is similar to a wet pond, but
Wet Pond, Constructed
shallower and supporting wetland vegetation in large areas. A
Wetland, Wet Vault
wet vault is an underground, covered, engineered structure that
retains a permanent pool of water.
A biofiltration swale is a long, gently sloped ditch or depression
Vegetated Biofilter - Designed to treat water as it passes through the vegetation.
Biofiltration Swale and Grass is the most common vegetation. A filter strip is a grass
Filter Strip area, wider than biofilters, also with gentle slopes. Water
usually enters as sheet flow from the adjacent pavement.
A structure placed in the landscape, with grass grown on top, or
in vaults. Stormwater passes through the sand allowing
Sand Filter
particulate pollutants to be filtered out.
A normally dry basin which temporarily stores stormwater
Infiltration until it soaks through the bottom and sides of the basin, and
infiltrates into surrounding soil.
See the King County Design Manual for allowable chemical
Chemical Treatment
treatment including chitosan and alum and CO sparging.
2
171
Oil/Grease
Sources: vehicle and equipment Oil/water separators; catch basin inserts; catch basin
areas, industrial areas, food sump/vault filters, leaf compost filters.
preparation
For coarse sediments -Wet pond/vault; constructed
wetland (with forebay); vegetated biofilter; sand filter;
Sediments/Solids
catch basin insert; catch basin sump/vault filters; leaf
Sources: sand/gravel storage,
compost filters. For fine sediments -Wet pond/vault;
construction sites, unpaved areas,
constructed wetland (with forebay); vegetated biofilter;
agriculture/livestock uses
sand filter. Also see catch basin sump/vault filters,
chemical treatment
Phosphor For particulate phosphorus -Wet pond/vault;
Sources: detergents/cleaners, constructed wetland (with forebay); vegetated biofilter;
fertilizers, organic matter, animal sand filter. If dissolved phosphorus must also be
wastesremoved -a large “oversized” wet pond or sand filter.
For particulate nitrate -Wet pond/vault; constructed
Sources: fertilizers, animal wastes, wetland (with forebay); vegetated biofilter; sand filter.
organic matter For dissolved nitrate - constructed wetland.
For particulate metals -Wet pond/vault; constructed
Sources: industrial areas, vehicle wetland (with sediment forebay); vegetated biofilter;
and equipment areas, paints, sand filter. For dissolved metals -leaf compost filter or
pesticides
constructed wetland.
There is no treatment BMP that can reliably reduce fecal
coliform bacteria to acceptable levels. Some studies have
Sources: animal wastes; fertilizers
shown constructed wetlands provide some benefit.
Sources: metal plating,
printing/graphic industries, A constructed wetland can neutralize some ranges of pH.
cement/concrete production,
cleaners
For particulate BOD - see “particulate nitrate” above. For
dissolved BOD -A constructed wetland will remove some
Sources: organic debris, food
dissolved BOD and trace organics; more reliable
wastes, some chemical wastes
performance requires activated carbon.
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6.0TECHNICAL ASSISTANCE
There is a variety of local and regional programs as wellas state and federal agencies that
can offer technical assistance in selecting and implementing BMPs. Many local
governments as well as private sector associations are available to provide suggestions and
guidance regarding the most effective and appropriate measures to take in order to protect
King County’s valuable water resources. This section provides names, contact information,
and brief descriptions of several sources of information and assistance available to the
businesses and residents of unincorporated King County.
In addition to the personal assistance offered by many organizations and programs, there is
also a broad range of written materials available to help businesses and residents select,
design, and understand applicable BMPs for water quality protection. This section provides
information that can help in the formation of pollution prevention strategies to protect
King County’s water quality.
6.1General BMP Selection
The Water and Land Resources Division has staff available to provide free on-site
consultations to businesses and residents for assistance in implementing the water
quality BMPs in this manual. For information, or to request an on-site consultation,
contact:
King County Water and Land Resources Division
201 South Jackson, Suite 5600
Seattle, WA 98104
206-477-4811
www.kingcounty.gov/stormwater
The Department of Ecology developed this manual as a model for local governments. It
contains requirements for stormwater management system design, erosion control, and
urban best management practices. Volume IV discusses source control. To obtain a copy
of the manual, go to:
https://fortress.wa.gov/ecy/ezshare/wq/Permits/Flare/2019SWMMWW/2019SWMM
WW.htm
Local trade or business associations can be valuable sources of information for specific
BMP applications on a business property. Many trade and business associations have
developed pollution prevention information for the benefit of their members that is
unique to their specific types of operations. Contact the appropriate trade or business
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association to obtain information, BMP assistance, and help in locating other businesses
that are working out similar problems.
6.2Sanitary Sewer and Septic Systems Resources
Contact your local sewer agency for information on allowable discharges and location of
your side sewer. The name of your local sewer agency is identified on your water and
sewer bill.
–
Information and regulation on on-site sewage treatment systems (septic systems) are
available for both property owners and on-site system professionals.
Eastgate Environmental Health Services
14350 SE Eastgate Way
Bellevue, WA 98007
206-296-4932
www.kingcounty.gov/healthservices/health/ehs/wastewater.aspx
–
The Industrial Waste Program provides information on what can be discharged to the
sanitary sewer. Industrial Waste can also assist with information for rerouting illicit
storm sewer connections to the sanitary sewer.
King County Industrial WasteProgram
201 S.Jackson St, Suite 500
Seattle, WA 98104
206-477-5300
www.kingcounty.gov/environment/wastewater/IndustrialWaste
6.3Waste Management and Recycling
The Solid Waste Division (SWD) provides garbage transfer, disposal and recycling
services for residents and businesses in all of King County, except for Seattle and Milton.
SWD also provides household hazardous waste disposal options and recycling
education programs for its residents.
King County Solid Waste Division
201 S. Jackson St, Suite 5701
Seattle, WA 98104
206-477-4466
www.kingcounty.gov/solidwaste/
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The Business Waste Line answers questions from small businesses about hazardous
waste. The Waste Line may also be used to report complaints and hazardous waste
violations.
Business Waste Line: 206-263-8899
www.kingcountyhazwastewa.gov
The Onsite Consultation Program provides free visits to businesses that request
assistance with hazardous waste handling and waste reduction. Only small quantity
waste generators or businesses that are potential small quantity waste generators
qualify for this service.
King County Hazardous Waste Management Program
201 S. Jackson St, Suite 5600
Seattle, WA 98104
206-296-4692
www.kingcountyhazwastewa.gov/business-disposal
This telephone hot line provides hazardous waste information and referrals to the
general public. (Businesses should call the Business Waste Line, also listed in this
Reference Guide.) The Hazards Line tells citizens where to dispose of their hazardous
waste and suggests less hazardous alternatives. It also provides operations times and
locations for household disposal sites for King County and the City of Seattle.
Hazards Line: 206-296-4692
www.hazwastehelp.org
–
This program assists businesses with recycling by: 1) providing information on waste
reduction and recycling services for particular needs; 2) helping you work with your
employees to promote participation; 3) offering information on buying recycled
products; and 4) providing you with ongoing support to ensure your program is
successful.
Workplace Recycling
King County Solid Waste Division
201 S. Jackson St, Suite 5701
Seattle, WA 98104
206-477-4466
www.kingcounty.gov/solidwaste/business/index.asp
–
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This program serves businesses in Seattle and King County that have questionable
wastes such as sludge, sandblast waste, treated wood, and contaminated soils. Waste
characterization staff assists generators with profiling their waste and determining if
the waste can be disposed of in the garbage. For some wastes staff will be able to
provide other options such as treatment, recycling, or reuse. The Health Department
issues authorizations for proper disposal.
ation
206-263-8528
www.kingcounty.gov/healthservices/health/ehs/toxic/SolidWaste.aspx
IMEX provides a free service helping businesses that have surplus materials find
businesses that need them. Surplus or waste materials, such as solvents, paint, plastics,
and wood, are exchanged. The website lists materials available and materials wanted.
IMEX is a component of the Hazardous Waste Management Program.
IMEX
201 S. Jackson St, Suite 5600
Seattle, WA 98104
206-296-4692 or imex@kingcounty.gov
www.kingcountyhazwastewa.gov/en/business-disposal/imex
The Department of Ecology has extensive information on managing and reducing waste,
hazardous waste and toxics reduction, and pollution prevention.
Waste and Toxics: www.ecy.wa.gov/waste.html
What you can do: www.ecy.wa.gov/green.html
The Department of Ecology is the source of information on businesses that provide
dangerous waste treatment, storage, and disposal (TSD) services, and information on
applicable regulations for TSD businesses.
www.ecy.wa.gov/waste.html
The Washington Toxics Coalition is a nonprofit organization dedicated to providing
information on reducing the use and production of toxic materials. The Coalition offers
fact sheets, research materials, and personal assistance to individuals interested in
reducing toxics (such as pesticides, solvents, cleaning chemicals, and a variety of other
chemicals) and finding safer alternatives to toxic materials.
Washington Toxics Coalition
4516 University Way NE
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Seattle, WA 98105
206-632-1545
www.watoxics.org
6.4Land Use, Fire Code, and Building Code
Requirements
The Department of Local Services Permitting Division (Permitting) should be consulted
to determine whether any permits may be required in constructing BMPs, modifying
property layout, or otherwise altering a site to control runoff contamination. If permit
requirements are overlooked or ignored, business or property owners may be subject
to fines. should be contacted while plans are being formed for BMPs, and before any
action is taken, to determine permit applicability and potential fees.
King County Local Services Permitting Division
35030 SE Douglas St., Suite 210
Snoqualmie, WA 98065-9266
206-296-6600
www.kingcounty.gov/property/permits.aspx
Questions on specific fire code requirements for individual site conditions and potential
BMP scenarios can be directed to the King County Fire Marshal’s office.
King County Fire Marshal
35050 SE Douglas St., Ste. 210
Snoqualmie, WA 98065-9266
206-296-6600
www.kingcounty.gov/fire
King County has enacted a Critical Areas Ordinance (CAO) to define and protect certain
land and water features throughout the county. The Environmental Education Section
of King County’s Department of Local Services Permitting Division (Permitting)
prepared a CAO User’s Manual that serves as a reference for the CAO in an easy-to-
understand format. The CAO User’s Manual can help determine special considerations
that may be necessary for implementation of BMPs within or near a designated
sensitive area. To obtain a copy of the manual, go to:
www.kingcounty.gov/property/permits/codes/CAO.aspx#manual
6.5Erosion Control Practices
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This manual contains the requirements and standards for designing surface and
stormwater management systems in King County. It also includes a chapter on erosion
and sediment control requirements for permitted sites.
To obtain a copy of the manual, go to:
www.kingcounty.gov/swdm
,
The Department of Ecology developed this manual as a model for local governments. It
contains requirements for stormwater management system design, erosion control, and
urban best management practices. Volume II discusses erosion and sediment control.
Toobtain a copy of the manual, go to:
https://fortress.wa.gov/ecy/ezshare/wq/Permits/Flare/2019SWMMWW/2019SW
MMWW.htm
This is a business association primarily for residential construction companies.
Members have experience in applying erosion and sediment control BMPs on both
small and large sites. The association can provide references on erosion and sediment
control products for use on construction sites as well as material suppliers who carry
erosion and sediment control products.
Master Builders Association of King and Snohomish Counties
335 116th Ave SE
Bellevue, WA 98004
425-451-7920
www.mba-ks.com/
This association provides information and training on erosion and sediment control for
contractors and field staff. The Association also provides resources in the areas of waste
disposal and erosion/sediment control. It provides information on recommended water
quality protection methods for contractors who maintain equipment yards or are
involved in building construction or site preparation activities, such as clearing and
grading.
Associated General Contractors of Washington
1200 Westlake Avenue North, Suite 310
Seattle, WA 98109
206-284-0061
www.agcwa.com/
6.6Air Quality
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The Puget Sound Clean Air Agency is the primary entity responsible for regulating air
pollution from business and industrial activities in King, Kitsap, Pierce, and Snohomish
counties. The agency issues air operating permits.
Puget Sound Clean Air Agency
1904 Third Avenue -Suite 105
Seattle, WA 98101
206-343-8800
www.pscleanair.org
6.7Environmental Organizations
ECOSS is a nonprofit organization that encourages urban redevelopment and a healthy
environment by providing education, resources and technical assistance to diverse
businesses and communities in the Puget Sound region. ECOSS helps business with
environmentally sustainable practices.
ECOSS
8201 10th Ave S, #3
Seattle, WA 98108
206-767-0432
www.ecoss.org
The Pacific Northwest Pollution Prevention Resource Center (PPRC) is a nonprofit
organization that provides pollution prevention information to business, government,
non-government organizations, and other sectors.
Pacific Northwest Pollution Prevention Resource Center
13751 Lake City Way NE, Suite 305
Seattle, WA 98125
206-352-2050
www.pprc.org/
Puget Sound Starts Here is a partnership of cities, counties, state and federal agencies,
nonprofit groups, and local organizations dedicated to improving water quality and
aquatic habitat in the Puget Sound region. Visit the website to find out how you can
protect Puget Sound as a resident.
www.pugetsoundstartshere.org
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6.8Quick Phone References
Contractors ................................................................ 206-284-0061
Environmental ............................................. 206-767-0432
........................................................................... 425-282-1900
............. 206-296-6600
............................................................................ 206-296-6600
................................................. 206-477-5300
.................. 206-296-4692
............................................................. 206-477-4466
............................................................ 206-477-4811
. 425-451-7920
........... 206-352-2050
..................................................................................... 206-343-8800
Seattle–
Business Waste Line ...................................................................................... 206-263-8899
Hazards Line (for households).................................................................. 206-296-4692
Industrial Materials Exchange (IMEX) ................................................... 206-296-4692
Wastewater Program (septic systems) .................................................. 206-477-8050
Waste Characterization ............................................................................... 206-296-4692
Northwest Regional Office (Bellevue) .................................................... 206-594-0000
Reporting of Spills .......................................................................................... 206-594-0000
Waste reduction and recycling .................................................................. 1-800-RECYCLE
....................................................................... 206-632-1545
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