According to §503.13 of the Code of Federal Regulations, “Bulk sewage sludge or sewage sludge sold or given away in a bag or other container shall not be applied to the land if the concentration of any pollutant in the sewage sludge exceeds the ceiling concentration for the pollutant in Table 1 of §503.13.

Table 1 of §503.13—Ceiling Concentrations

Pollutant Ceiling concentration (milligrams per kilogram)1
Arsenic 75
Cadmium 85
Copper 4300
Lead 840
Mercury 57
Molybdenum 75
Nickel 420
Selenium 100
Zinc 7500

1Dry weight basis.

(2) Cumulative pollutant loading rates.

Table 2 of §503.13—Cumulative Pollutant Loading Rates

Pollutant Cumulative pollutant loading rate (kilograms per hectare)
Arsenic 41
Cadmium 39
Copper 1500
Lead 300
Mercury 17
Nickel 420
Selenium 100
Zinc 2800

(3) Pollutant concentrations.

Table 3 of §503.13—Pollutant Concentrations

Pollutant Monthly average concentration (milligrams per kilogram)1
Arsenic 41
Cadmium 39
Copper 1500
Lead 300
Mercury 17
Nickel 420
Selenium 100
Zinc 2800

1Dry weight basis.

(4) Annual pollutant loading rates.

Table 4 of §503.13—Annual Pollutant Loading Rates

Pollutant Annual pollutant loading rate (kilograms per hectare per 365 day period)
Arsenic 2.0
Cadmium 1.9
Copper 75
Lead 15
Mercury 0.85
Nickel 21
Selenium 5.0
Zinc 140

(c) Domestic septage. The annual application rate for domestic septage applied to agricultural land, forest, or a reclamation site shall not exceed the annual application rate calculated using equation (1).

eCFR graphic ec15no91.192.gifView or download PDF

Where:

AAR = Annual application rate in gallons per acre per 365 day period.

N = Amount of nitrogen in pounds per acre per 365 day period needed by the crop or vegetation grown on the land.

[58 FR 9387, Feb. 19, 1993, as amended at 58 FR 9099, Feb. 25, 1994; 60 FR 54769, Oct. 25, 1995]”

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