HomeMy WebLinkAboutPermit L99-0063 - WA STATE DEPARTMENT OF TRANSPORTATION - SPECIAL PERMISSIONL99 -0063
WSDOT NOISE
VARIANCE
I -405 GREEN RIVER
W. VALLEY HWY.
BRIDGES
SPECIAL PERMISSION)
A F F I D A V I T O F D I S T R I B II T i O N
QNotice of Public Hearing
Notice of Public Meeting
Q Board of Adjustment Agenda
Packet
['Board of Appeal Agenda
Packet
QPlanning Commission. Agenda
Packet
Short Subdivision Agenda
Packet
hereby declare that:
Notice of Application far
Shoreline Management Permit
QShoreline Management Permit
Determination of Non-
significance ■'
Mitigated Determination of
Nons ignificance
ODetermi nation of. Significance
and Scalping Notice
Li Notice of .Action
0 Official Notice
Other
Q i ti:e.;At� /
was mailed to each :of the fallowing addresses an
Name of Praject_l� bS
File Number L7 /' 002
S icnature
9/c9-/99
City of Tukwila John W. Rants, Mayor
Department of Community Development Steve Lancaster, Director
DETERMINATION
BY THE DIRECTOR OF THE DEPARTMENT OF COMMUNITY DEVELOPMENT
REGARDING A NOISE VARIANCE
Prepared September 1, 1999
FILE NUMBER:
APPLICANT /OWNER:
REQUESTS:
LOCATION:
COMPREHENSIVE
PLAN DESIGNATION:
ZONE DESIGNATION:
SEPA
DETERMINATION:
PUBLIC NOTICE:
STAFF:
L99 -0063 (WSDOT I -405 Noise Variance)
Washington State Dept. of Transpiration (WSDOT)
Bruce Farrar, Program Manager, Air Quality and Special Studies
Approve a four (4) day, temporary noise variance to allow night
repair of two bridges on I -405. Construction would occur between
September 22, 1999 and October 22, 1999.
The I -405 bridge crossing of the Green River and West Valley
Highway in Tukwila, WA.
This roadway is functionally classified as a "Freeway ".
Not Applicable.
SEPA Exempt.
None.
Vernon Umetsu, Associate Planner
ATTACHMENTS
A. Letter from the Washington State Dept. of Transpiration (8/13/99)
B. Letter from the Washington State Dept. of Transpiration (8/25/99)
6300 Southcenter Boulevard, Suite #100 • Tukwila, Washington 98188 • (206) 431-3670 • Fax (206) 431-3665
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L99 -0063: WSDOT I -405 Temporu1y Noise Variance
Page 2
FINDINGS
BACKGROUND
Construction noise is exempt from regulation between 7:00 A.M. and 10 P.M.' but otherwise
regulated by TMC 8.22. The proposed construction noise would occur during regulated hours
and exceed the allowed noise level of 50 dB(A) by 5 to 15 dB(A).2.
Construction could only occur during regulated hours with a noise variance from the Director of
the Department of Community Development3. The requested "temporary variance" is a
ministerial decision and does not require a public hearing 4.
VICINITY /SITE INFORMATION
1. Project Description: The applicant's request for a four (4) day temporary variance is
shown in attachments A and B. The construction sites are two consecutive bridges on I-
405: one over the Green River and the second over West Valley Highway (see air
photograph in Attachment A).
WSDOT proposes construction typical of normal bridge joint repair. This would include
concrete burr removal, repair and sealing.
Maximum noise levels would be from the impact of chipping hammers as burrs are
removed and air compressors. Chipping hammer noise would occur for less than five
seconds a few times per night. Air compressors would operate frequently. Several sound
mitigation measures are proposed in Attachment A and B.
3. Existing Site Development: The concrete bridges are part of I -405 with 3 traffic lanes
and shoulders in each direction. The bridges are elevated 15 to 25 feet above the general
ground level.
Surrounding Land Use: Surrounding areas are generally commercial uses which are not
occupied during the 10 p.m. to 7:00 a.m. variance period, with four exceptions:
♦ two single family residences 200 and 500 feet from the bridge repair sites,
• the Hampton Inn (motel) 150 and 800 feet from the bridge repair sites,
'TMC 8.22.160(4).
2Assumes that 1-405 is an "industrial" area and recognizes the single family receiving areas as residential.
Such a situation allows a maximum 50 dB(A) noise level (TMC 8.22.040 and 050(1)). This is the maximum
variance situation.
3TMC 8.22.190(A) and 8.22.020(1).
4TMC 18.22.180.
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L99 -0063: WSDOT I -405 Temporary Noise Variance
Page 3
♦ Homestead Village (motel) 500 feet from the bridge repair sites and
♦ Family Fun Center (amusement park) is open 9 a.m. to midnight, 7 days per week.
These sites are shown on the site map in Attachment A
DECISION CRITERIA
A "temporary noise variance" may be issued by the D.C.D. Director, acting as the
"administrator," pursuant to TMC 8.22.180(B): "...at the reasonable discretion of the
administrator." The criteria to grant or deny a temporary noise variance is shown in bold and
followed by staff discussion.
1. No variance shall be granted pursuant to this chapter until the administrator has
considered the relative interests of the applicant, other owners or possessors or (sic)
property likely to be affected by the noise, and the general public. (TMC
8.22.180(C))
Noise Standards
a. Construction noise is exempt from regulation except between 10 p.m. and 7 a.m.
During those times, the proposed freeway construction noise impacts on
residential receiving districts is limited to 50 dB(A) per TMC 8.22.050(1)5.
Maximum impacts on commercial districts is 65 dB(A) (ibid.).
b. "No sound source specifically exempted from a maximum permissible sound level
by this chapter shall be a public nuisance noise or public disturbance noise..."
(TMC 18.22.140). This applies to the proposed freeway construction during non-
regulated hours.
Noise Impacts
c. EPA thresholds of acceptable noise were recognized and incorporated into the
"Tukwila Comprehensive Plan Environmental Impact Statement" (October,
1995:pg.47) as follows:
55 or less Levels are generally acceptable; no noise impact is generally
associated with these levels.
55 -65 dB(A) Adverse noise impacts exist; this measurement represents the
lowest level possible without adverse significant impact.
65 -70 dB(A) Significant noise impacts exist; allowable only in unusual cases
where lower levels are not possible.
5This assumes that the freeway is an "industrial" "District of Sound Source." A commercial district is limited
to 47 dB(A) while a residential source is limited to 45 dB(A) (TMC 8.22.150(1)). No other adjustments per
8.22.150(2) or (3) seem to be appropriate.
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L99 -0063: WSDOT I -405 Temporuuy Noise Variance
Page 4
over 70 dB(A) Levels of unacceptability for public health and welfare
considerations.
d. WSDOT has estimated sound levels at the four properties occupied during the
variance period based on Federal Highway Transportaion Administration
guidelines in attachments A and B.
e. The subject residential buildings have single pane glass windows, which readily
reduce outside noise by 20 dB(A). The motels were built with double pane glass,
which can reduce noise levels by 25 dBA. This would mean occasional
maximum noise levels as follows:
On -site Receiving Area
Two single
family
residences
Hampton
Inn6
Maximum Allowed Sound Level (TMC
18.22050(1)).
Residential
Zones =
50 dB(A)
Commercial
Zones =
65 dB(A)
Maximum Outside Sound Level -- Maximum
noise levels are from the chipping hammer and
would last for a few seconds several times per
night. More frequent air compressor noise levels
would be 5 dB(A) less.
55 -65 dB(A)
67 -69 dBA
Inside noise level with single pane windows (20
dB(A) reduction).
32-40 dB(A)
N.A.
Inside noise level with double pane windows (25
dB(A) reduction).
N.A.
42 -44 dBA
f. The Family Fun Center amusement park is the only occupied site that is likely to
have visitors exposed to outside sound levels of 68 dB(A). The normal
amusement park on -site noise is anticipated to mask bridge repair noise for park
visitors.
g.
The proposed construction noise is exempt during the day. Daytime bridge repair
would impact receiving properties, when more sites would be occupied.
h. The City of Tukwila has granted two technical noise variances issued (L94 -0068
and L96- 0080). Estimated noise levels at residential receiving sites were much
higher than projected here. No noise complaints were received.
6 Homestead Village (motel) is estimated to receive maximum sound levels of 55 to 57 dB(A). The Family
Fun Center is estimated to receive maximum sound levels of 68 dB(A).
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L99 -0063: WSDOT I -405 Temporaiy Noise Variance
Page 5
Congestion Impacts
i. The construction would require significant lane closures resulting in significant
and dramatic traffic congestion. Late night closure would minimize congestion
impacts.
2. The noise occurring or proposed to occur does not endanger public health or safety;
(TMC 8.22.180(C)(1))
The anticipated maximum noise levels are below the EPA guidelines for avoiding
significant human health impacts, as shown in a comparison of Finding 1 c and 1 d.
3. The "...activity, use, process or equipment...in accordance with rules and
regulations, the does not annoy a substantial number or the people and does not
endanger public health or safety." (TMC 8.22.18.22.180(C)(2) and 190(B))
a. See Finding for Criteria 2.
b. The alternative of daytime construction (when the proposed freeway construction
noise is exempt) would shift the noise levels from the night to the day, when
many more receiving sites would be occupied and the occupants affected are more
likely to perceive significant (congestion) impacts. The impacts of extreme traffic
congestion would also spill over to residential and commercial areas.
c. Staff conditions to monitor and implement mitigation programs as needed have
been reviewed with the applicant. They have been accepted and incorporated into
the construction documents.
CONCLUSIONS
The balance between the relative interests of the applicant, other property owners and the
general public seem to be served by granting the variance given the following:
a. maximum noise levels will be significantly reduced indoors to an acceptable EPA
noise level and be of a short duration and
b. not granting the variance would still subject the receiving properties to the same
level of noise impact between 7 a.m. and 10 p.m., and result in an extreme level of
traffic congestion.
B. Sound levels authorized by the variance are not anticipated to significantly endanger
public health and safety, based on estimated noise levels at the receiving properties, EPA
estimates of significant noise levels, the applicant's previous ability to avoid noise
complaints and the proposed conditions of approval.
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L99 -0063: WSDOT I -405 Temporary Noise Variance
Page 6
C. The above findings do not indicate an available, practical means to prevent, abate, or
control the noise level below what is proposed.
DETERMINATION
Based on the above Findings and Conclusions, the proposed 4 day, temporary noise variance to
be used between the period September 22, 1999 through October 22, 1999, is APPROVED
subject to the following conditions':
1. The occupants of the two residences, and the management of the two hotels and the
amusement park shall be notified of the construction with pertinent information at least five
days (5) prior to the first night of construction.
2. A 24 hour complaint hot line shall be established and have immediate connection to a
WSDOT on -site inspector who has been instructed on this variance and has the authority to
respond to complaints. Response shall include authority to evaluate the level of impact,
take equipment out of service, and otherwise resolve the complaint. The hot line phone
number shall be in the notice of construction (see Condition 1).
3. A WSDOT person well versed in noise mitigation measures will conduct a training session
with maintenance personnel. This session will include the requirements of the variance,
construction equipment involved, way to keep the noise to a minimum, and consequences of
failure to comply with the variance. WSDOT will submit a confirmation document to the
City noting all WSDOT and other inspectors who attend this training. In addition to
providing the training, WSDOT shall grant the necessary authorization to have an
acoustics expert /inspector on site at all times to ensure immediate enforcement actions of
all mitigation measures.
4. All backup warning devices shall be the least intrusive ambient sensitive type or the
contractor may use a back -up observer in lieu of backup warning devices as allowed in
WAC Ch. 296 -155- 610(2) (e).
5. All material spilled on the roadway shall be removed by hand methods or sweeping. No
scraping type equipment shall be used
6. All truck beds used in the removal of debris will be lined with rubber to reduce noise
impacts.
7. Residential areas shall be shielded from stationary equipment, such as air compressors,
generators, and light plants.
8. Maximum noise levels shall be as presented, +1- 2dB(A).
' Conditions in italics were proposed as part of the application.
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L99 -0063: WSDOT I -405 Temporary Noise Variance
Page 7
9. All equipment shall be tested to ensure that maximum noise thresholds and characteristics
incorporated in the noise analysis are as anticipated.
10. All complaints shall be forwarded to the Director as soon as possible the following day.
11. All complaints shall be resolved within 24 hours of WSDOT receipt, based on the
provisions of this variance. City staff shall be available to assist in resolution.
12. Complaint resolution shall include, but not be limited to:
a. site visits and monitoring,
b. withdrawal of equipment not satisfying the identified maximum noise levels or
characteristics and
c. offering to move the residents to a City approved facility. A list of facilities shall be
submitted for City approval prior to night -time construction. Facilities shall be safe,
clean, and have general equivalence to a residence.
13. Receipt of 2 or more complaints within a 48 hour period shall justify modifying or revoking
the provisions of this variance.
14. Take any alternative measures that the Director may prescribe to mitigate noise impacts per
TMC 18.22.190(A), based on the provisions of this variance.
Steve Lancaster
Director
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Date
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v707 17):psahrhateo:tSotfarans
Sid Morrison
Secretary of Transportation
Michael Jenkins
Assistant Planner
City of Tukwila
6300 Southcenter Boulevard
Tukwila, WA 98188
Dear Mr. Jenkins:
Pursuant to the stipulations of the temporary noise variance, the Washington State
Department of Transportation (WSDOT) conducted a training course on noise mitigation
measures. The class, held on September 8, 1999, included maintenance personal
associated with this project. This session included the requirements of the variance,
•
construction equipment involved, ways to keep the noise to a minimum, and consequences
of failuit to comply with the variance. Attached is a list noting all WSDOT personal who
attended this training.
portation
Northwest Region
15700 Dayton Avenue North
P.O. Box 330310
Seattle, WA 98133-9710
(206) 440-4000
September 15, 1999 •
• /-1-)
.... 4 Q
Temporary Noise Variance Request
State Route 405
MA 5920
Bridge Deck Expansion Joint Repair
If you have any questions please call Me at (206) 440-4546 or Janelle Hitch at (206) 440-
4541 •
• • BPF/jch
• Attachments
cc: Charles Shoop MS 49
file
MA5920class.DOC
Sincerely,
BRUCE P. FARRAR
Air Quality and Special Studies
Program Manager
0
� Washington State
�I/ Department of Transportation
Sid Morrison
Secretary of Transportation
Michael Jenkins
Assistant Planner
City of Tukwila
6300 Southcenter Boulevard
Tukwila, WA 98188
Dear Mr. Jenkins:
Oki,
Northwest Region
• 15700 Dayton Avenue North
P.O. Box 330310
Seattle, WA 98133 -9710
(206) 440-4000
August 13, 1999
RECEIVED
CITY OF TUKWILA
AUG 1 6 1999
PERMIT CENTER
Temporary Noise Variance Request
State Route 405
MA 5920
Bridge Deck Expansion Joint Repair
The Washington State Department of Transportation (WSDOT) is planning to complete
bridge deck expansion joint repair on several bridges along State Route (SR) 405. This
maintenance project is being conducted to ensure safe operations for the traveling public.
Costlier and more time consuming repairs will result if the needed work is not performed
immediately.
This maintenance project will be conducted at bridge decks located in the cities of
Tukwila, Renton, Seattle, and Bellevue. The repair work on bridge decks located within
the City of Tukwila include:
• SR 405 Overcross of Green River; and
• SR 405 Overcross of SR 181; •
It is noted that there are no proximate residences to the SR 405 Overcross of SR 181.
Attached is a vicinity map showing the project location and plan sheets showing the bridge
deck locations. Expected project generated peak noise levels are also included.
WSDOT traffic analysis has determined that by performing lane closures during the day,
traffic congestion due to high traffic volumes and loss of roadway capacity will occur.
Such large scale backups would not be acceptable. WSDOT recommends that lane
closures be done at night when traffic volumes are low enough to handle lane closures
without causing congestion. • Additionally, this will facilitate public and worker safety.
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The projected dates (weather dependent) of repair work are September 26 and 27, 1999.
The hours of nighttime lane closure are from 10:00 PM to 4:30 AM. Information
regarding traffic control and equipment data for this project is attached.
This maintenance project operations include the set up of traffic control devices and repair
of expansion joints. Equipment to be used may include, but is not limited to, chipping
hammer, air compressor, generator, trucks, light plants, arrow boards, and truck mounted
impact attenuators.
We propose the following measures to minimize impacts:
A. A WSDOT person well versed in noise mitigation measures will conduct a training
session with maintenance personnel. This session will include the requirements of the
variance, construction equipment involved, ways to keep the noise to a minimum, and
consequences of failure to comply with the variance. WSDOT will submit a
confirmation document to the City noting all WSDOT and other inspectors who attend
this training. In addition to providing the training; WSDOT shall grant the necessary
authorization to have an acoustics expert /inspector on site at all times to ensure
immediate enforcement actions of all mitigation measures.
B. All required backup alarms to be used at night will be the least obtrusive OSHA
approved ambient sensitive type.
C. All truckbeds used in the removal of debris will be lined with rubber to reduce noise
impacts.
D. With regard to material removed or placed during open cut operations, any material
spilled on the roadway surface shall be removed by sweeping. No scraping type
equipment shall be used.
E. Stationary equipment such as light plants, generators, or any other shall be shielded
from residential areas.
F. After two (2) substantiated continuing complaints are received and reviewed, the State
may be required to accomplish testing in the bedrooms of affected residents. If tests
are above 52 dBA during construction, then the State will be required to take further
mitigation measures such as, but not limited to, insulating the windows or providing
motel accommodations.
The WSDOT respectfully requests that the City of Tukwila consider and grant a 4 day
noise variance from the constraints of Chapter 8.22.050 (A) per the provisions of Chapter
8.22.180 and 8.22.190 of the Tukwila Municipal Code. We request a one month window,
beginning September 22, 1999, in which to use the issued variance nights.
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I apologize for the short notice regarding this application. Your timely response is much
appreciated. If you have any questions please call me at (206) 440 -4546 or Janelle Hitch
at (206) 440 -4541
BPF /jch.
Attachments
cc: Charles Shoop MS 49
Day file
file
MA5920C.DOC
BRUCE P. FARRAR
Air Quality and Special Studies
Program Manager
ti
PROJECTED NOISE LEVELS, TRAFFIC CONTROL, AND EQUIPMENT DATA
Traffic Control on the project will include shifting and reducing the width of the existing
lanes of traffic between the construction zones and the traveling public. The repair work
will require closure of up to two existing traffic lanes. Traffic control, including arrow
boards, will be used during nighttime construction activities. It is the region's policy that
construction projects minimize impacts to the traveling public and, with the heavy traffic
volumes on SR 405, limit lane closures to nighttime hours.
The equipment we anticipate to use would include:
Traffic Control Equipment:
Light plants
Arrow boards
Truck mounted impact attenuators
Repair Equipment:
Chipping hammer
Air compressor
Generator
Trucks
Equipment varies in decibel output depending on many factors. However based on
previous observations, the expected noise level for each piece of equipment is the
following:
Light plants: 75 dBA a 50 feet
Arrow boards 75 dBA @ 50 feet
Chipping hammer 85 dBA @ 50 feet
Air compressor 80 dBA rr 50 feet
Generator 75 dBA a 50 feet •
Trucks 75 dBA @ 50 feet
Noise levels diminish with distance. A 6 dBA noise level drop will occur with the
doubling of distance from the noise source. For example, a noise level of 70 dBA
measured at 50 feet would be 64 dBA at 100 feet, 58 dBA at 200 feet and 52 dBA at 400
feet. Sound also decreases if an object interferes with the receiver's line of sight to the
noise source. This attenuation depends on the relative elevation of the source and the
receiver and the height and location of the intervening object.
The following overview describes construction generated noise levels expected to occur to
specific neighborhoods adjoining the SR 405 bridge maintenance project
The following projected noise levels will result from nighttime repair activities on the SR
40.5 Noise levels resulting from the subject project's repair activities will generate peak
noise levels of 75 to 85 dBA as perceived at 50 feet. Ambient traffic at design speeds
would generate peak noise levels of 70 to 90 dBA as perceived at 50 feet. Project
generated noise levels are expected to be as follows:
SR 405 Overcrossing of Green River
One residential dwelling is located proximal to the SR 405 overcrossing of Green River
where bridge deck work is scheduled to occur. The residence lies to the northwest of the
SR 405 /Green River overcrossing. Distance attenuation (200 to 500 feet from the work
site to residence) will result in an approximate 12 to 20 dBA reduction. Portable noise
shields will be employed around work activities providing further attenuation benefits of 8
to 10 dBA. Repair activity noise levels are expected to generate peak exterior noise levels
of 55 to 65 dBA at this receptor site.
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WI Washington State
. Department of Transportation
Sid Morrison
Secretary of Transportation
Vernon Utnetsu
Associate Planner
City of Tukwila
6300 Southcenter Boulevard
Tukwila, WA 98188
0
Northwest Region
15700 Dayton Avenue North
P.O. Box 330310
Seattle, WA 98133 -9710
(206) 440-4000
August 25, 1999
Temporary Noise Variance Request
State Route 405
MA 5920
Bridge Deck Expansion Joint Repair
Dear Mr. Umetsu: •
Per our phone conversation of August 24, 1999, AM, please find the requested
supplemental data below.
The Homestead Village Studios (a residential motor inn) and the Hampton Inn are
respectively located in the southwest and southeast quadrants of the Green River
interchange (SR 405 /SR 181). The Homestead Village Studios building is located
approximately 500 feet from the closest expansion joint repair area. Distance attenuation
will provide a 20 dBA reduction from worst case repair activity noise levels of 85 dBA
(chipping hammer as treasured from 50 feet). Portable noise shields will be placed around
the chipping hammer operations, resulting in additional mitigation benefits of 8 to 10 dBA.
This will result in exterior peak noise levels of 55 to 57 dBA as perceived from the
Homestead Village proximity. The Hampton Inn is located approximately 150 feet (8
dBA distance attenuation) from the repair area, which would result in occasional exterior
peak noise levels of up to 67 to 69 dBA (including noise shield benefits). This noise
projection is for the portion of the Hampton Inn closest to the repair site. It is noted that
interior noise levels, effected by repair activities, would be 20 dBA less than exterior noise
levels. It is also noted that chipping hammer operations will be occasional and short in
duration.
Two residential dwellings are located above 68`t' Avenue S. near the SR 405 /Green River
Bridge. It is unknown if the dwelling closest to the repair site is occupied. Field
inspection was inconclusive. Peak exterior noise levels for this area are expected to be 55
to 65 dBA when distance attenuation and noise shields are factored in.
Ar-r4ciB
The Washington State Department of Transportation will notify the motor inns'
management and 68th Avenue S. residents a minimum of 5 business days in advance of
• nighttime repair activities.
If you have any questions or comments please call me at (206) 440 -4546 or Janelle Hitch
at (206) 440 -4541
BPF/jch
cc: Charles Shoop MS 49
Day file
file
MA5920C.DOC
BRUCE P. FARRAR
Air Quality and Special Studies
Program Manager
File: L 99 -0063
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