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5. BASIS OF PLANNING Under the new federal regulations 40 CFR, Part 503, maximum concentrations, cumulative pollutant loading rates, average pollutant limits or "clean biosolids," and annual pollutant loading rates have been established for nine heavy metals. Table 5.1.4-2 shows the acceptable levels for land application. These rates are used to determine site life, which is the number of years that biosolids with a uniform metal content could be applied to a specific site. However, MWMC has adopted a policy that pollutant concentrations in biosolids be half of the federally required standards. TABLE 5.1.4-2 New Federal Regulations (40 CFR, Part 503) for Heavy Metalsa MWMC Facility Plan, Eugene-Springfield Average Maximum Cumulative Average Concentration Concentration Loading Concentration Loading Rate Parameter (mg/kg) (kg/ha) (mg/kg) (kg/ha/yr) Arsenic 75 41 41 2.0 Cadmium 85 39 39 1.9 Copper 4,300 1,500 1,500 75 Lead 840 300 300 15 Mercury 57 17 17 0.85 Molybdenum 75 18 0.90 Nickel 420 420 420 21 Selenium 100 100 100 5.0 Zinc 7,500 2,800 2,800 140 a From 40 CFR, Part 503 (December 1992). Site Identification and Approval Prior to approving any potentially sensitive application site (with respect to residential housing, runoff potential, or groundwater threat), DEQ may require an opportunity for public comment and public hearing. A statement of land use compatibility from the responsible planning jurisdiction should accompany requests for approval of biosolids land application sites. New sites or expansion of existing sites must be proposed to DEQ prior to use. Newly approved sites become part of the biosolids management plan. Site criteria for land-applying biosolids include physical geographical features (geological formation, flood plain proximity, and groundwater and surface water proximity, topography, and soils), and method of application. DEQ's specific criteria are outlined in Table 5.1.4-3. Special Management Considerations Land receiving bulk Class B biosolids for agricultural use requires special management considerations. These relate to access to the site, types of crops grown, plant nutrient rates, MWMC_5.0_R EV8_VKS.DOC 5-15