# 40 CFR Appendix A to Part 503 - Procedure To Determine the Annual Whole Sludge Application Rate for a Sewage Sludge

Appendix A to Part 503 - Procedure To Determine the Annual Whole Sludge Application Rate for a Sewage Sludge

Section 503.13(a)(4)(ii) requires that the product of the concentration for each pollutant listed in Table 4 of § 503.13 in sewage sludge sold or given away in a bag or other container for application to the land and the annual whole sludge application rate (AWSAR) for the sewage sludge not cause the annual pollutant loading rate for the pollutant in Table 4 of § 503.13 to be exceeded. This appendix contains the procedure used to determine the AWSAR for a sewage sludge that does not cause the annual pollutant loading rates in Table 4 of § 503.13 to be exceeded.

The relationship between the annual pollutant loading rate (APLR) for a pollutant and the annual whole sludge application rate (AWSAR) for 1a sewage sludge is shown in equation (1).


$\mathrm{APLR}=C×\mathrm{AWSAR}×0.001\phantom{\rule{5em}{0ex}}\text{(1)}$
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).
AWSAR = Annual whole sludge application rate in metric tons per hectare per 365 day period (dry weight basis).
0.001 = A conversion factor.

To determine the AWSAR, equation (1) is rearranged into equation (2):


$\mathrm{AWSAR}=\frac{\mathrm{APLR}}{C×0.001}\phantom{\rule{5em}{0ex}}\text{(2)}$

The procedure used to determine the AWSAR for a sewage sludge is presented below.

Procedure:

1. Analyze a sample of the sewage sludge to determine the concentration for each of the pollutants listed in Table 4 of § 503.13 in the sewage sludge.

2. Using the pollutant concentrations from Step 1 and the APLRs from Table 4 of § 503.13, calculate an AWSAR for each pollutant using equation (2) above.

3. The AWSAR for the sewage sludge is the lowest AWSAR calculated in Step 2.