Friday, September 16, 2011

Draft General Permit for Infrequent Discharges in Arizona

The Arizona Department of Environmental Quality (ADEQ) has released its proposed General Permit for Infrequent Discharges (AZGP2011-001). This general permit can be used by a limited type of wastewater dischargers. The permit is applicable only to secondary treated effluent discharges from domestic wastewater treatment facilities with a design flow of less than 20 million gallons per day (mgd). Infrequent discharges are routine discharges that occur no more frequently than twice per calendar year with a duration of no more than 14 consecutive days and at least 30 days between discharges. Emergency discharges at these facilities would occur no more than three times per permit term with a duration of no more than 14 consecutive days per discharge event. It is estimated that only 20 to 40 facilities in Arizona will meet the definition of an infrequent discharger.

The draft permit includes technology-based effluent limitations, monitoring requirements, including whole effluent toxicity (WET) testing, and reporting requirements similar to other AZPDES permits.

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