Section NR 256.04 - Monitoring and reporting requirements(1) TOTAL TOXIC ORGANICS. An indirect discharger may elect to monitor for oil and grease as an alternate to TTO under PSES and PSNS regulatory values. Due to the high solubility of toxic organics in oil and grease, compliance with the oil and grease standard is considered equivalent to compliance with the TTO standard.(2) NONCONTINUOUS DISCHARGERS.(a) For noncontinuous direct dischargers, the department shall apply effluent limitations or standards in the form of mass-based annual average, concentration-based maximum day and concentration-based maximum monthly average as indicated in the tables within this chapter.(b) For noncontinuous indirect dischargers, the control authority may elect to establish concentration-based standards as outlined in sub. (3).(3) CONVERSION TO CONCENTRATION-BASED UNITS. (a) The control authority may apply concentration-based standards which are exactly equivalent to PSNS and PSES mass-based standards. Concentration-based standards shall be derived by the following procedure:(b) Multiply PSNS or PSES mass-based standards by a) average production (kkg of metal poured), b) raw material usage (kkg of sand reclaimed), or c) air scrubber flow (Sm3 of air scrubbed), whichever applies, and divide by average discharge flow to the POTW. In calculating, use appropriate measurements and conversion factors to ensure that concentration-based units in mg/l result.(4) MONTHLY DISCHARGE LIMIT. Compliance with the monthly discharge limits, as calculated from monthly average regulatory values from tables contained in this chapter, is required regardless of the number of samples analyzed and averaged.Wis. Admin. Code Department of Natural Resources NR 256.04
Cr. Register, June, 1989, No. 402, eff. 7-1-89.