WAC 173-308-900. Appendix A—Procedure to determine the annual whole biosolids application rate

When biosolids are sold or given away in a bag or other container for application to the land, and any of the pollutant concentration limits in Table 3 of WAC 173-308-160 are exceeded, the mathematical product of the concentration in the biosolids of each pollutant listed in Table 4 of WAC 173-308-160 and the annual whole biosolids application rate (AWBAR) must not cause the annual pollutant loading rate for the pollutant in Table 4 of WAC 173-308-160 to be exceeded. This appendix contains the procedure used to determine an AWBAR that does not cause the annual pollutant loading rates in Table 4 of WAC 173-308-160 to be exceeded. The relationship between the annual pollutant loading rate (APLR) for a pollutant and the annual whole biosolids application rate (AWBAR) is shown in equation (7). Equation (7) APLR  =  C* AWBAR* 0.001 Where: APLR = Annual pollutant loading rate in kilograms per hectare per 365 day period. C = Pollutant concentration in milligrams, per kilogram of total solids (dry weight basis). AWBAR = Annual whole biosolids application rate in metric tons per hectare per 365 day period (dry weight basis). 0.001 = A conversion factor. To determine the AWBAR, equation (7) is rearranged into equation (8): Equation (7) APLR  =  C* AWBAR* 0.001 Where: APLR = Annual pollutant loading rate in kilograms per hectare per 365 day period. C = Pollutant concentration in milligrams, per kilogram of total solids (dry weight basis). AWBAR = Annual whole biosolids application rate in metric tons per hectare per 365 day period (dry weight basis). 0.001 = A conversion factor. To determine the AWBAR, equation (7) is rearranged into equation (8): Equation (8) AWBAR = APLR C* 0.001 Equation (8) AWBAR = APLR C* 0.001 The procedure used to determine the AWBAR is presented below. Procedure: 1. Analyze a sample of the biosolids to determine the concentration for each of the pollutants listed in Table 4 of WAC 173-308-160 . 2. Using the pollutant concentrations from Step 1 and the APLRs from Table 4 of WAC 173-308-160 , calculate an AWBAR for each pollutant using equation (8). 3. The correct AWBAR is the lowest AWBAR calculated in Step 2.