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HomeMy WebLinkAboutSEPA EPIC-ND-11 - CAL-ORE MACHINERYCAL-ORE MACHINERY EPIC-ND-1 1 ENVIRONMENTAL ASSESSMENT SUMMARY WITH EMPHASIS . ON WATER QUALITY FOR CAL -ORE MACHINERY PREPARED BY WILSEY & HAM,INC. APRIL 1974 I. INTRODUCTION II. EXISTING CONDITIONS A. Water Quality in the Green /Duwamish River. B. Sampling Results. CONTENTS III. IMPACT A. Projections of Water Quality Impact as a Result of Development of the Site. 1) Methods 2) Results IV. APPENDIX 1. INTRODUCTION The historical drainage pattern of the Green River Valley has been altered_ by the industrialization of the valley. Within the vicinity of the pro- posed Cal -Ore site, drainage patterns have been altered by the construc- tion of river levees, highway right -of -ways and a rail track easement. Development of the proposed Cal -Ore site will be a continuation in this trend of alteration of natural runoff patterns of the area. The proposed action, will result in the development of five acres of land adjacent to the Green River for the purposes of a retail center and a machine shop for Cal -Ore. The proposed plans will result in about 50% coverage of the site in build- ings and paved surfaces. The rest of the site will be an unpaved gravel display area and some landscaped areas. When development of the site is completed, drainage will be routed towards an existing drainage ditch, which is located between the site and West Valley Highway. Runoff collected in this ditch is then routed under- neath the West Valley Highway to a point a short distance away where it drains into the Green River. The proposed site plans also include specifications for a wash area for machinery. The wash area effluent will be retained in a grit chamber and will be routed through an oil skimmer in order to provide an accept- able dishcarge into the METRO system. After the settling and skimming, the wash water will be routed through an existing METRO trunk line to the Renton Treatment Plant, which is a secondary treatment facility.. The questions addressed in this discussion are the water quality impli- cations of both the runoff from the site as well as the effluent from the wash area. In order to address these questions, first the water . quality of the Green River is discussed in general terms with some comments in regard to the Renton Treatment Plant. Sampling data obtained from an adjacent site being utilized for purposes similar to those pro- posed for the Cal -Ore site is given. Following is a discussion of probable impact based on long range projections. Included in the appendix is a brief description of some of the other biophysical elements. II. EXISTING CONDITIONS A. Water Quality in the Green - Duwamish River The Duwamish River Estuary is an important industrial waterway and has been receiving industrial, municipal, and storm water wastes since the early 1900's. In the 1940's fisheries - resource agencies and commercial interests became concerned about the, impact of degraded water quality on the rich aquatic life of the estuary. In 1958, in response to growing water quality problems throughout the Seattle metropolitan area, Seattle area residents voted to form the Municipality of Metropolitan Seattle (METRO). METRO is a federation of cities united to deal with waste water disposal and transportation service. The METRO Comprehensive Sewerage Plan includes an extensive network of sewer trunklines and several sewage treatment plants. The Renton Treatment Plant is located approximately one -half of a mile downstream from the site and discharges treated effluent at that point. Thus, for most water quality parameters, except coliform counts, the Renton Treatment Plant overshadows the effluent from upstream sources (see Tables A and B).• Since June 1965, the .Renton Treat- ment Plant (RTP) has been "dishcarging increasing amounts of treated effluent to the Duwamish River as new trunklines have been constructed and the treatment plant's service area has been enlarged. The design capacity of the present Renton secondary treatment process is 36 million gallons per day, although the actual volume of effluent varies. In recent years, a number of studies have been performed to determine the water quality effects of the various effluents into the river. From these, a brief overview of the river can be obtained. From 1963 to 1967 METRO and the U. S. Geological Survey conducted a cooperative study of water quality in the lower Duwamish River in order to determine the chemical, physical, and ecological changes that take place in the estuary when raw or partially- treated wastes are replaced by treated effluent from the Renton Treatment Plant. This study was primarily concerned with the hydraulics of the estuary, the physical and chemical characteristics of the water (temperature, dissolved oxygen, and bio- chemical oxygen demand), and certain aspects of the ecology relating to the plankton communities. The findings of this early study have been substantiated by later studies performed by Dr. Eugene Welch at the University of Washington in 1967 and 1969, and by the RIBCO (the River' Basin Coordinating Committee, . a technical advisory committee to METRO) Water Quality Management Study Interim Report of October 1973. Conclusions regarding the interpretation of past trends and data, as well as specific estimates of possible future impacts affecting the Duwamish Estuary and Green River will be available in the near future as RIBCO completes its estuary studies. TABLE A WATER QUALITY - KENT TO ELLIOTT BAY JUNE 1973 Coliform Counts (100m1) Metro Total Fecal Ammonia/ Phosphate Silica' Dissolved Conductivity Temperature Station Coliform Coliform Nitrate (mg /1) (mg /1) (mg /1) Oxygen umhos /cm °C (mg /1) 306 6,400 120 .48 .50 .24 16.3 307 9,400 50 .11 .26 .09 - - 12.8 3077(1) 3,400 20 21.25 1.28 4.80 17.0 3106 1,400 42 .70 .50 .35 - - 17.1 3107 1,200 20 .38 .49 .26 - 17.2 351(2) 110 20 .02 5.20 8.0 151 18.8 3108 700 50 .18 .49 .20 - 17.2 311(3) 1,400 67 • .12 .46 .17 - 17.3 312(4) 660 20 .10 .42 .42 .21 17.9 315 510 20 .15 .40 .14 - - - - 17.4 - - No Data •. -(1) Ranier Vista effluent (2) Renton Treatment Plant (3) Immediately downstream of subject (4) Immediately upst4eam of subject site TABLE B WATER QUALITY - KENT TO ELLIOTT BAY DECEMBER .1973. Coliform Counts (100 ml) Metro Total Fecal Station Coliform Coliform 306 1,900 130 307 7,600 980 3077(1) 520 24 3106 400 20 3107 380 20 351 (2) 20 0 3108 311 (3) 312(4) 315 No Data Ranier Vista effluent. Renton Treatment Plant, Immediately downstream of subject Immediately upstream of subject site 180 Ammonia/ Phosphate Silica Dissolved Conductivity Temperature Nitrate (mg /1) (mg /1) (mg /1) Oxygen umhos /cm °C . 18 .43 .16 - - 8.4 .21 .45 .13 - - 8.3 4.13 1.29 4.48 - - 14.0 . 17 .40 .12 - .05 .39 .09 - - - 14.80 .13 3.24. - 20 .04 .40 .09 720 20 .04 .42 420 170 .05 180 20 .05 .40 .34 .09 11.67 68 .09 7.0 6.5 15.0 6.3 6.5 6.5 Just upstream of the subject site, conditions of low dissolved oxygen have often been recorded in the late summer. The Green - Duwamish River still experiences similar low dissolved conditions during the summer months. Although the most recent METRO six - month report analyzing data from March 1973 through October. 1973 indicates an improving trend in dissolved oxygen, the RIBCO analysis indicates low dissolved oxygen levels are still a problem. Low dissolved oxygen in the Duwamish Estuary is attributable to . oxygen consumption by benthos (bottom organisms) and algae as well as high temperatures due to shallow depths, low flows, . and inadequate shading. However, it appears to be highly unlikely that the present anadromous fish runs or annual aquatic ecosystem of the Duwamish will be affected by dissolved . oxygen depressions, according to RIBCO biologists. By way of a general note, dissolved oxygen is a key parameter in the Green - Duwamish River and in similar streams that have com- mercially and recreationally important fish populations. The respiratory processes of fish, shellfish, benthos, etc. are affected by changes in dissolved oxygen content. Fisheries are an important Green River resource. The Green River steelhead catch ranked second statewide for the 1969 -70 and 1970 -71 winter seasons, and third in 1971 -72. Steelhead catches ranged from 8,000 to 17,000 fish. The Department of Game maintains a steel - head rearing facility at Palmer to help supplement Green River . steelhead productivity: The dissolved oxygen is depleted by the oxidation (degradation) of natural as well as man -made materials and is replaced naturally by aeration at the air -water surface or by mixing with water having greater dissolved oxygen and /or by photosynthesis of aquatic plants. Since the degradation of the more common wastes requires their oxidation, the variation in dissolved oxygen is a significant indicator of the general amount and persistence of pollutants. The capacity of water to retain dissolved oxygen is also reduced with increasing temperatures. Upstream from the proposed site, the river may be loaded slightly beyond its natural B.O.D. (Biological Oxygen Demand) as indicated by the fact that both the average dissolved oxygen values and average B.O.D. values at the Renton Treatment Plant monitoring station ( #351) are generally lower than at the monitoring station upstream of the subject site ( #312). The high B.O.D. in the river adjacent to the site is probably due to the cumulative effect of numerous point sources of effluent, one of which is the discharge from the outfall through which drainage from the developed site will be routed. This outfall is a relatively minor source, and thus, it is possible that effluent from the outfall has only a small direct effect on dissolved oxygencon- centrations in the lower river and estuary. However, this effect is a cumulative one when considered in relationship to the num- erous other point sources of effluent. • Temperatures for the river from the monitoring station 315 at Kent to just downstream of the proposed site are lower than those which would indicate thermal pollution levels. The river responds to inputs of warmer water from the .Renton Treatment Plant as shown by several stations downstream. At station 3077, a small decrease occurs as a result of the Ranier` Vista Treatment Plant effluent, then the influence of Elliott Bay seawater is registered. If the drainage from the site adds to .a source of thermal pollution, its effect is certainly overshadowed by the Renton Treatment Plant. Ammonia and phosphate concentrations in the Green /Duwamish River are relatively low adjacent to the subject site but have signifi- cantly increased downstream from the Renton Treatment Plant out - fall since the introduction of the effluent in 1965. The Renton Treatment Plant is only 16% efficient for ammonia and 3% efficient for phosphates. The concentrations of these nutrients are at least doubled as a result of the present input of treated effluent from the plant. According to METRO data, the Renton Treatment Plant is a quite significant source of nitrites and nitrates. The impact on aquatic life in the estuary attributable to this input of nutrients is, however, unknown at this time. Maximum concen- trations of all nutrients in the Duwamish Estuary occur at low tide, partly because at this time there is a minimum of seawater dilution of fresh water nutrient sources. High levels of nutrients are also recorded in the fall and winter, however, when light conditions are minimal, a severe algal bloom cannot be sustained. Nuisance blooms and •eutrophication are well known problems that develop from increases in phytoplankton production frequently caused by nutrients in domestic waste water. However, the USGS Study indicates that in the case of the Duwamish River, nutrient concentrations do not control the occurrence of the blooms inas- much as nitrogen and phosphorous compounds always are present in . sufficient quantities for a. bloom to exist. For example, previous data indicates that a bloom occurred prior to the installation of the Renton Treatment Plant. The chief factors controlling whether or not a phytoplankton bloom will occur are . favorable hydrological and climatic conditions. Nutrients from the paved surfaces resulting from the continued process of indus- trialization of the Green River Valley may function to increase the biomass produced by phytoplankton blooms once the other favor- able conditions are established. The dissolved oxygen of surface waters is increased by the photo- synthetic process of the bloom, but the dissolved oxygen of the subsurface waters is decreased as the plants die and oxygen is consumed in decomposition processes. Coliform concentrations in the Duwamish River exceed the median count established by the water quality standards, according to the last six -month METRO report. Although a good relationship between total and fecal coliform is not evident, the same general trend, of increasing contamination in downstream locations is apparent . in the fecal coliform count as well. Soluble trace metal concentrations for copper and lead (Table C) are fractions of a part per billion in the estuary water. This data was obtained from the trace metal laboratory, University of Washington, Department of Oceanography, core sampling within the estuary. The fate of metals borne by the river is transferral to the sediments. The concentrations of lead and zinc at the surface of the cores and one meter deep in the cores (Table B) are extremely high and demon -. strate how effectively the transfer proceeds. The cores were obtained in June, 1973, and were analyzed by the Region Ten Environ- mental Protection Agency Laboratory. Since nearshore ocean sediments . contain an average of 60,000 ppb lead and 150,000 ppb zinc, it appears that the Duwamish Estuary sediments have been greatly enriched by inputs from the river and from industrial sites around the estuary. The site will constitute several sources of heavy metals which will be introduced to the river including: auto- exhaust borne lead, metals in the runoff as well as those contained in the - wash area effluent. Such introduction of metals to the river system will comprise an undetectable increase in the already heavily loaded sediments. B. SAMPLING RESULTS In order to gain an idea of actual water quality parameters, samples . were taken from an adjacent developed site (N. C. Machinery) which is similar to the development proposed by Cal -Ore. Samples were taken on March 25, 1974, at 4:00 at two locations. Samples were taken from the discharge pipe which drains the adjacent site. Also, samples were taken from the retention basin which holds wash water from the wash area prior to discharge into METRO's Renton Treatment Plant. Sampling data is given in Table. D. Sample methods and analysis were performed according to methods specified in Standard Methods for the Examination of Water and Waste Water, 13th edition. Nutrients were anlayzed by a technician Auto Analyzer II. Turbidity was measured on a HACH Model 2100A Turbidi- meter. Coliforms, both .total and fetal, were tested and analyzed by methods specified in Standard Methods for the Examination of Water and Wastewater, 13th Edition. There had been a dry period of approximately seven days prior to the day samples were taken. On the day the samples were obtained there had been a light precipitation. It should be noted that to obtain conclusive data on water quality characteristics of runoff from such a facility, a continuous monitor - ing.program is necessary. The.data obtained from the.samples is useful to gain approximate idea of existing conditions. However, • the data reflects conditions and uses that occurred on that date and such conditions and uses taking place on the site do change from time to time as the weather and human activities change. METALS CONCENTRATIONS IN DUWAMISH ESTUARY (parts per billion) Soluble Metals Date 9/13/72 Location West Waterway 6/01/71 West Waterway 9/13/72 East Waterway 6/01/72 East Waterway Sediments (Total Acid Soluble) Depth (Meters) 0 15 8 17 0 15 3 8 13 Depth Core No. Location (Meters) Pb Zn 12 Duwamish Mouth 0 71,000 130,000 11 Duwamish Mouth 0 194,000 25,000 - 1 152,000 20,000 10 Duwamish Mouth 0 195,000 400,000 - 1 .18,000 69,000 16 East Waterway. 0 346,000. 600,000 Pb 0.15 0.16 0.15 0.40 0.4 0.4 0.4 0.44 0.07 0.13 - 1 61,000 140,000 TABLE WATER QUALITY SAMPLING RESULTS FROM A SIMILAR PROJECT SITE. (March 25, 1974) Runoff Discharge to Duwamish. Temperature °C 18° C. pH 6.9 Dissolved Oxygen 11.0 mg 02 /liter B.O.D. 8.0 mg 02 /liter Specific Conductivity 68.0 mho /cm2 Total Dissolved Solids 42.84 mg /liter Turbidity 8.9 J.C.U. Color 20.0 Units Ammonia- Nitrogen (NH3 -N) Nitrate-Nitrogen (NO3 -N) Ortho -P Alkalinity Zinc Oil &.Grease Coliforms Total Coliforms Fecal Wash Rack Basin 20° C. 6.65 4.4 mg 02 /liter 4.0 mg 02 /liter 80 mho /cm2 50.4 mg /liter 165 J.C.U. > 100 Units 1.30 mg /liter 9.6mg /liter 2.7 mg /liter .37 mg /liter 20 mg /liter as CaCO3 .148 mg /liter .930/100/m1 0 /100 /ml 1.25 mg /liter 2.0 mg /liter 123 mg /liter as CaCO 3 .420 mg /liter. 132.0 mg /liter 110,000 /100 /ml' .40 /100 /m1 • Of particular note is that the wash water, prior to the time it is pumped into METRO, is high in biological oxygen demand and in oils and grease. Conditions in the sump are such that all available oxygen is drained from the system in five days. The wash water also has high total coliform counts, but low fecal coliform counts. This shows that the source of coliform is the soil washed off the machinery. III. IMPACT A. Projections of Water Quality Impact as a Result of Development of the Site. 1) Methods In the previous section, the studies undertaken by the River Basin Coordination Committee (RIBCO) were mentioned. Part of the RIBCO studies involved a model where by the water quality impact of the runoff from different types of land uses can be projected. Varying amounts of pollutants were found to build up during dry periods on a typical acre depending on the land use classification. Then, according to the intensity and duration of rainfall, a percentage of these pollutants will wash off. In the case of the subject site, the runoff carrying these pollutants is routed into a ditch which drains into the Green River. Thus, using the RIBCO model, the concentration of pollutants in an average liter of runoff from the site reaching the river during different weather conditions can be calculated. The projections of pollutant concentrations can be performed for innumerable weather situations, however for the purposes of this analysis, the following four weather situations were chosen on the basis of weather information obtained from the National Weather Service. In June of 1973 there was only one day in which 0.5 inches or more of rain fell. In an extreme case in the summer there might be a 30 day period of no rain during which time pollutants build . up on the land and then are washed off in .a rainfall in which 0.5 inches rain falls in one hour (see the first column of Table E). In December of 1973, there were seven days in which 0.5 inches or more of rain fell. In an extreme case during December there might be 4.5 days of no rain during which time pollutants build up on the land and then are washed off in a rainfall in which 0.50 inches rain falls within one hour. (See second column of Table E). Rainfalls of 0.1 inches or more are considerably more frequent in both the winter and summer. In December there were 25 days in which 0.10 inches or more rain fell and in June there were nine days in which 0.10 or more inches fell. So, for the purposes of this analysis, a typical case might be one in which there is a relatively short interval of no rain followed by 0.10 inches falling within one hour for both winer and summer (see Table F). According to The Seattle Rain Gage Program and Rainstorm Data, by H. W. Duff and G. C. C. Hsieh (October 1969),. a rainfall of 0.5 inches in an hour might occur in a 10 year storm and 0.1 inches rainfall will occur several times a year. TABLE E WATER QUALITY PROJECTIONS (.5 in. rain /one hour) WEATHER: SUMMER or 30 Days - No Rain WINTER or 4.5 Days - No Rain T-- LAND USE INDUSTRY OPEN. AVERAGE INDUSTRY OPEN Imp. Area 95% 5% 50% . 95% 5% ACRES (of each land use) 2.5 2.5 Total = 5.0 2.5 2.5 BOD mg /liter) Imp. 92.94 4.28 48.6 13.94 Per. 92.94 4.28 . 48.6 .13.94 TOTAL COLIFORM ( #100 /mg) Imp. 5,253,600 14,184,600 9,719,100 788,000 Per. . 5,253,600 14,184,600 9,719,100.. 788,000 FECAL COLIFORM (# /100 mg) Imp. Per. ORGANIC NITROGEN (mg /liter) (NO3 +NO2 -N) Imp. Per. AMMONIA- NITROGEN (mg /liter) Imp. (NH3) Per. 89,310 89,310 1.62 1.62 NITRATE - NITROGEN Imp... Per. (mg /liter) (NO3) 47.6 47.6 .59 .59 PHOSPHATES (mg /liter) (PO4) Imp. 7.00 .476 Per. .70 .70 141,846 141,846 115,578 115,578 13,400 13,400 AVERAGE 50% Total = 5.0 0.64 7.29 0.64 7.29 78,800 78,800 800 800 433,400 433,400 7,100 7,100 :714 1 :18 73 :10 .42 .714 1.18 .73 .10 .42 .618 .618 24 :1 24.1 7.15 7.15 .09 . . • 3.62 3.62 .09 .33 . .46 .09 .05 .07 .35 .: .47 9.65 .05 4.85 1.07 .07 . .57 TABLE F WATER QUALITY PROJECTIONS (0.1 in. rain /one hour) WEATHER: SUMMER or 3.33 Days - No Rain WINTER or 1.24 Days - No Rain LAND USE INDUSTRY . OPEN AVERAGE INDUSTRY OPEN AVERAGE Imp. Area 95% 5% 95% 5% ACRES (of each land use) 2.5 2.5' 2.5 2.5 BOD (mg /liter) Per. Imp. TOTAL COLIFORM (# /100 mg). 21.20 .73 10.96 7.89 .36 4.1 21.20 .73 10.96 7.89. .36 4.1 Per. 1,619,854 161,985 890,919 Imp. 1,619,854 161,985 890,919 FECAL COLIFORM (# /100 mg) Per. 27,536 1,620 14,578 14,578 Imp. 27,536 ORGANIC NITROGEN (mg /liter) (NO3 +NO2-N) Imp. 0.49. Per. 0.49 AMMONIA + NITROGEN- (mg /liter) Imp. (NH3) 14.7 Per. 14.7 NITRATE- NITROGEN (mg /liter) Imp. (NO3), 1,620 446,359 446,359 27,537 27,537 44,635 245,497 44,635 245,497 446 13,990 446 13,990 Per. PHOSPHATES (mg/liter) (PO4) Imp.. Per. • • According to the RIBCO analysis, a.rai nfai1 of 0.5 inches in an hour will wash off 90% of the pollutants built up in the preceeding dry period. By the same manner, a rainfall of 0.10 inches in an hour will wash off 37% of the pollutants. Thus, the following formula was used in the water quality pro- jections: . • Number of Washoff RIBCO Waste Acres x Dry Oays x Factor (above) x Load Factor Results. Liters of Runoff The previous data, both the sampling results and the pro- jections, indicate that the subject site runoff will con - stitute a source of B.O.D., coliform and nutrients to the Green. River. Also the site will contribute B.O.D. and oils and grease to the METRO system. The projections of contaminants in the runoff give an indication of the long -term impact of light industrial facilities in general. The sampling data is specific for the site but reflects conditions at one point . in time. The relative volume of runoff that can be expected from the Cal -Ore site are small as compared to volumes experienced in the receiving drainage ditch and certainly the volume is minuscule as compared to the Green River. However the increase in pollution loads which can be expected from developed sites as opposed to undeveloped sites readily demonstrates how the urbanization of a watershed can result in cumulative deleterious water quality impact. For example, development of the site will increase the anticipated con- tribution of biological oxygen demand in surface runoff 20 to 50 times over the present conditions. Coliforms can be expected to increase by about five times over the existing. conditions. The difference in nitrate- nitrogen may not be measurable, however, the other nutrients will increase sig- nificantly. In conclusion, continued urbanization of the Green River. Valley will create further water quality problems in the Green River, although the site itself, when viewed alone would create an imperceptible change in the total river. system. IV. APPENDIX EXISTING CONDITIONS - THE NATURAL ENVIRONMENT A. The Area Directly Involved The area directly involved is the site of the proposed Cal -Ore Machinery Company facility in Tukwila. The proposed site is typical of areas of the Green River Valley which have experienced extensive man -made alterations. The site is a triangular 5 acre lot located between the West Valley Highway and the Green River. The Milwaukee Road has an easement along the southwest boundary of the site for a rail track which services the Andover Industrial Park. The river side of the site . has been diked. Within the immediate vicinity of the proposed site are a number of industrial uses including the N. C. Equipment shop south of the site and the Andover Industrial Park across the river. Extensive industrialization is occurring in this portion of the Green River Valley. Also, several elements of the regional transportation network are in close proximity to the site including Interstates 5 and 405, S. R. 167, and S. R. 181. B. Topography Historically the Green River created a mature flood plain as it meandered through the Tukwila area. Relief on the flood plain on the site approximates six feet (between elevations + 24 and +30) Regional relief is 400 - 600 feet. As a result of the rapid industrialization and the construction of freeways, highways, rail- road tracks and dikes, most of the flood plain in Tukwila has been artificially regraded and, in many places, filled. C. Geology - Soils The soils found in the Green River Valley in the Tukwila area has been developed from the alluvial deposits of the White, Cedar, Black. and Green Rivers. According to the most recent U.S.D. Soil Conservation Service (SCS) soil survey of King County, surface soil of the subject site is composed of Newberg silt loam.. Newberg silt loam is a coarse well- drained alluvial soil distinguished by surface layers of very dark grayish -brown silt loam and very fine sandy loam. This twenty -inch thick layer is underlain by deep layers of stratified very fine sandy loam, loamy very fine sand, loamy sand, and silt loam. Newberg soils'are typically found behind natural levees bordering major streams. In the Green River watershed, Newberg soils generally comprise the portion of the flood plain nearest to the river. Due to their level topography, loamy texture, good tilth, and deep profiles with high water - holding capacities, Newberg soils are , excellent agricultural soils. The U. S. Department of Agriculture has classified Newberg soils as Class II soils. Class II soils are primary agricultural soils with few limitations or hazards reducing the choice of plants or requiring moderate conservation practices for sustained production of commonly cultivated crops. The SCS notes that "Newberg soils are one of the soils best suited for such use in King County." Primary agricultural soils constitute a finite regional resource. Within the portion of King County outside of national forest lands, only 13,830 acres of soil are classified as inherently suitable for sustained agricultural production as Newberg soils. Only eleven percent of the 445,000 acres of King County (exclusive of national forests are composed of primary agricultural. soils. The primary conservation management problems associated with Newberg soils is overbank flow flooding and the maintenance of soil productivity. Soils are best suited for most urban purposes when they provide good drainage, are free from floodwater hazard, provide firm foundations for typical urban structures, and have low shrink swell properties. Freely draining soils with low corrosivity are generally desirable. Poorly adapted soils can usually be made acceptable by engineering design. All Class It alluvial soils in the King County area typically have properties not highly suitable for urban use. The proposed project will result in covering agricultural soils, and excluding this potential use, however, due to the small size of the site and its relationship to surrounding uses which also preclude agriculture, farming is no longer feasible at this location. D. Botany The original plant community of the Green River Valley which probably consisted of a mixed Red - cedar, Douglas -fir, and Big -leaf Maple forest has been totally disrupted by prior human activity. Many of the alterations which have occurred in this portion of the valley have been mentioned. The subject site is typical of disturbed portions of the Green River Valley where vegetation has been allowed to re- establish for a short period of time and herbaceous shrubs (early to mid - successional plant communities) occur. If trees are allowed to grow the shrub mid- successional plant community is characterized by the thickets it forms. These are made up of Blackberries, Salmonberries, Red Elder- berries, Vine Maple, Willows and Sitka Mountain Ash. Blackberry and Sitka Mountain Ash thickets predominate drier areas along the river while the Salmonberries, Vine Maple's, Red Elderberries and Willows prefer shaped, cooler and wetter areas. Often patches of Himalayan Blackberry also occur. • •. Development of the site will, of course, remove the early to mid successional herbaceous shrub communities. In all probability, the growth of vegetation along the diked portions of the site will have to be ' controlled in order that access may be provided for equipment utilized in flood control activities. Thus the utility of the site for animal habitat purposes is limited. E. Biology 1. Fisheries The Green River produces hundreds of thousands of resident and non - resident fish annually, the majority of which are released as fry or fingerlings from the Washington State Department of Fisheries Hatchery on Big Soos Creek, one half mile above its juncture with the Green River. This hatchery is the largest in the Puget Sound area and is considered to be one of the most productive salmon hatcheries in the state. As many as 50,000 fish return to the hatchery during peak years. Sub- stantial natural spawning also occurs. Fish species of the Green River include Chinook, Coho, and Chum Salmon; Cutthroat, Dolly Varden, Steelhead and Rainbow Trout; Prickly Sculpin; Threespine Stickle Back, Longnose, and Speckled Dace, Mountain White Fish and Starry Flounder (juveniles) . 2. Terrestrial and Aquatic Wildlife - Birds and Mammals The Green River, as it flows through Tukwila is part of the Pacific Migratory Waterfowl Flyway. Birds known to most probably occur in the Lower Green River Valley freshwater environment and the predominantly early to mid - successional vegetational environments of the dikes and immediately adjacent areas are given in the following table. Inspection of this list of birds discloses that most species are ecologically dependent on marsh and pond habitats which are be- coming more scarce as regional urbanization proceeds. Many aquatic, marsh and shore bird species find their essential animal or plant foods in the water or on the mud and sand edges of the river. Many migrant birds must also use the area in the later summer and through the fall as well as in the late winter and spring. Existing growing thickets of willows and cottonwoods will provide increasingly effective wildlife habitat if they are allowed to remain along the diked areas. However, the value of the river edge habitat will be reduced as the adjacent lands are developed and accordingly less habitat area and food sources are available. The development of the project site will contribute to the over- all trend of reduction of available habitat areas. CHART Disregarding the many waterfowl and shorebird species which are attracted to the Green River and its shores, the following additional bird species are . quite likely to be seen within the proposed project site and its adjacent areas. Common Name Red - tailed Hawk Rough- legged Hawk Marsh Hawk Sparrow Hawk Ruffed Grouse California Quail Ring- necked Pheasant Barn Owl Screech Owl Short -eared Owl Common Nighthawk Rufous Hummingbird Red - shafted Flicker Yellow - bellied Sapsucker Downy Woodpecker Rough- winged Swallow Red-breasted Nuthatch House Wren Swainson's Thrush Golden- crowned Kinglet Ruby- crowned Kinglet Water Pipit Starling Red -eyed Vireo Warbling Vireo Orange- crowned Warbler Nashville Warbler Yellow Warbler Myrtle Warbler Western Meadowlark Bullock's Oriole Brown- headed Cowbird Black - headed Grosbeak Pine Siskin Oregon Junco White- crowned Sparrow Golden - crowned Sparrow Lapland Longspur R= Resident M= Migrant S= Summer only W= Winter only Scientific Name Seasonality Buteo jamaicensis. Buteo lagopus Circus cyaneus Falco sparverius Bonasa umbellus Lophortyx californicus Phasianus colchicus Tyto alba Otus asio Asio flammeus Chordeiles minor Delasphorus rufus Olaptes cafer Sphyrapicus varius Dendrocopos pubescens Stelgidopteryx ruficollis Sitta canadensis' Troglodytes aedon Hylocichla ustulata Regulus satrapa Regulus calendula Anthus spinoletta Sturnus vulgaris Vireo olivaceus Vireo gilvus Vermivora celata Vermivora ruficapilla Dendroica petechia Dendroica coronata Sturnella neglecta Icterus bullockii Molothrus ater Pheucticus melanocephalus Spinus pinus Junco oreganus Zonotrichia leucophrys Zonotrichia artricapilla Calcarius lapponicus W R R R R R R R S S R R S , S R . W W R. S S S M S W R S S S R R M . W