Okla. Stat. tit. 27A, § 27A-2-6-501.5: Agricultural use of sludge

Sludge shall only be used on agricultural land at agronomic

rates, as determined by the Department, provided the application is

performed in accordance with an approved sludge management plan or

permit and the rules promulgated by the Board which shall include,

but shall not be limited to, the following:

1. Annual land application of sludge shall not exceed nitrogen

and phosphorous fertilization rates for the crop grown and shall not

be applied at rates that result in phytotoxicity;

2. Sludge applied to land shall be incorporated into the soil

before the end of each working day;

3. Sludge shall not be applied within two (2) feet of the

highest seasonal water table nor applied to the land within one

hundred (100) feet of a stream or body of water; and

4. Sludge shall not be applied within two hundred fifty (250)

feet of a public or private water supply.