Member Pipeline - Regulatory - Alert (RA 00-18)
To: Members & Affiliates From: National Office Date: September 5, 2000 Subject: EPA Draft National Guidance on Permitting in the Absence of a TMDL Reference: RA 00-18 The Water Permits Division of EPA's Office of Wastewater Management has been developing national guidance on issues related to water quality-based permitting for discharges to impaired waters prior to establishment of TMDLs. The key issues and options for a national guidance were discussed this summer with staff and managers in the NPDES program in the Regional Offices, as well as with officials in various EPA headquarters offices. The enclosed Rough Draft, "Permitting Discharges to Impaired Waters Before a TMDL is Established," has been prepared by EPA to clarify the agency's guidance to permitting authorities on developing a National Pollutant Discharge Elimination System (NPDES) permit for a point source discharge to an impaired waterbody.
When completed, the guidance document will supplement EPA's 1991 Technical Support Document for Water Quality-based Toxics Control (TSD). The 'rough draft' imposes tough interim permitting requirements on point sources of pollutants, while failing to address nonpoint sources of pollution and de minimis discharges. The draft says, An important principle of the TSD's approach to assessing the need for water quality-based effluent limits (WQBELs) is consideration of background concentrations." The consideration of background concentrations may result in in the elimination of 'dilution' and mixing zones in waters where ambient criteria are exceeded. Other sections of the draft guidance address options for data reevaluation and numeric criteria.
AMSA members have been critical of a similar interim permitting guide created by EPA Region IX earlier this summer. In presenting an overview of the 'rough draft' at AMSA's 2000 Summer Conference in July, an EPA official predicted the final guidance could be released by October. AMSA will meet with EPA officials to present POTW concerns this month.