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Mr. Jerry Lile (DTSC) <br /> Page 6 of 7 <br /> waterbodies from the above example would be between 6 and 45 parts per trillion. <br /> Moreover, these water bodies are flushed by tidal action and the runoff would not enter <br /> the water bodies instantaneously. Significant mixing would take place and an excursion <br /> of receiving water above applicable standards would not occur. In any event, the soluble <br /> copper will not be rapidly transferred to surface water because of minimal contact with <br /> rain runoff and because it will be utilized by native vegetation as explained below. <br /> • The water-soluble copper in the soil will be taken up and utilized by vegetation. Copper <br /> is an essential micronutrient for plant life. The affected area is vegetated with Bermuda <br /> grass and bordered by a dense wild blackberry thicket whose root system underlies the <br /> area. Tissue analysis of various berry fruits has found a normal copper content ranging <br /> from approximately 2-50 ppm (Oregon State Univ.). Analysis of boysenberry leaves <br /> finds 8-29 ppm (Horticultural and Food Research Institute of New Zealand) Assuming <br /> an average copper content of 25 ppm in blackberry plant tissue, the removal rate is <br /> approximately 2.5 E-05 pounds of copper per pound of plant tissue shed annually. To <br /> remove the 3 E-02 pounds of soluble copper in each 1,000 square feet of affected area <br /> would require 1,200 pounds of plant tissue...realistic over a period of several years. <br /> Data on the tissue content of copper in grass was lacking, however it may be similar to <br /> alfalfa or cereal grains at about 4-8 ppm (Alberta. Agriculture, Food and Rural <br /> Development) <br /> • Fertilizer application at recommended rates creates soil concentrations similar to those <br /> existing at the site and reflects the uptake of copper by plants. For cropland it is <br /> recommended (Alberta) that an application of 3-7 pounds per acre of soluble copper to <br /> mineral soil and 10-15 pounds per acre of organic soil should provide adequate nutrition <br /> for a period of up to ten years. This is an application rate of 6.9 E-02 to 3.4 E-01 pounds <br /> per 1,000 square feet or up to 10 times the level present in the affected soil. For lawns, <br /> the recommended application rate of Miracle-Gro fertilizer is 5.60 E-04 pounds of <br /> soluble copper per 1,000 square feet every week or two. Assuming a growing season of <br /> 7 months, the annual application rate is between 7.8 E-03 and 1.6 E-02 pounds of soluble <br /> copper per 1,000 square feet which is similar to the quantity in the affected soils. <br /> Backup information for the above observations and assertions is included in Attachment C. <br /> CONCLUSIONS AND RECOMMENDATIONS <br /> The area affected by elevated concentrations of copper is probably 1,000 square feet or less. This <br /> affected area contains less than 3 E-02 pounds of water-soluble copper. Although the <br /> concentrations of soluble copper in the DI-WET extracts of several samples were above the <br /> aquatic life protection standard for copper in fresh water, it is highly unlikely that runoff would <br /> actually contain copper at this level. It is practically impossible for the affected soil to cause an <br /> G:\GROUNDZE\MARINA\VillageWest\Aquatoxrpt.doc <br />