40 CFR 466.03 - Monitoring and reporting requirements.
(a) Periodic analyses for chromium as may be required under part 122 or 403 of this chapter is not required when both of the following conditions are met.
(1) The first wastewater sample of each calendar year has been analyzed and found to contain less than 0.08 mg/l chromium.
(2) The owner or operator of the porcelain enameling facility certifies in writing to the control authority or permit issuing authority that chromium is not contained in the raw materials or process chemicals of that facility and will not be used in the facility.
(b) The “monthly average” regulatory values shall be the basis for the monthly average discharge in direct discharge permits and for pretreatment standards. Compliance with the monthly discharge limit is required regardless of the number of samples analyzed and averaged.