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NPDES permits, such as the daily maximum limitation of 72 mg/1 

 of oil and grease in discharges of produced water established by the 

 effluent guidelines for the offshore subcategory. 



Both exploration and production operations of the oil and gas 

 extraction industry generate discharges subject to NPDES permit 

 limitations. As you are familiar, these operations discharge drilling 

 fluids, drill cuttings, produced waters, deck drainage, and sanitary 

 and domestic wastes which are limited in part by the technology- 

 based effluent limitations guidelines. As you may know, our prima- 

 ry concern on the OCS has been with drilling fluids (or muds) and 

 drill cuttings which, depending upon the nature of the receiving 

 waters, have been regulated differently through NPDES permits. 



For the discharges I have just described, NPDES permits issued 

 after July 1, 1977, contain interim effluent limitations based on the 

 more stringent of effluent guidelines, representing best practicable 

 control technology (BPT), or limitations necessary to meet the 

 water quality standards of the receiving waters. 



When finally promulgated for new sources, final effluent limita- 

 tions will be based on new source performance standards. Until 

 new source performance standards are promulgated in about 18 

 months, discharges of conventional pollutants, such as oil and 

 grease, will be governed by best conventional pollutant control 

 technology or BCT. 



Most important for this hearing today, in addition to the technol- 

 ogy based limitation I have just described, section 403 of the act 

 may require more stringent permit limitations for discharges into 

 the oceans. Congress paid special attention to discharges into the 

 oceans and charged permit writers to make such complex determi- 

 nations as the effects of pollutants on marine organisms, including 

 ecosystem diversity, productivity, and stability, and esthetic, recre- 

 ation, and economic values, as well as human health. Furthermore, 

 these determinations are to be made prior to issuing an NPDES 

 permit. Based on these determinations, limitations necessary to 

 minimize or prevent significant degradation, that is language from 

 the act, may be imposed in the NPDES permit issued to a marine 

 discharger. 



EPA will promulgate in the near future ocean discharge guide- 

 lines to aid permit writers in making these determinations. Until 

 that time, section 403(a) provides that a permit may be issued for a 

 marine discharge if it is in the public interest to do so. 



Our interim policy for implementing section 403(c) provides that 

 the criteria set forth in that section which I alluded to above are to 

 be considered and applied in the issuance, reissuance or review of 

 all NPDES permits for ocean dischargers. In addition, the ocean 

 dumping criteria are to be applied to the fullest extent possible 

 where appropriate. 



As you may be familiar, the primary aspect of the ocean dump- 

 ing criteria that concerns us for the ocean discharge area is compli- 

 ance with the "Limiting Permissible Concentration" (LPC). The 

 LPC means discharge of that concentration of a pollutant which 

 will not cause unreasonable acute or chronic toxicity or cause 

 sublethal adverse effects on marine organisms. The scientific tests 

 to determine an LPC for specific pollutants are laboratory tests 

 conducted with appropriate sensitive marine organisms. 



