BARNES HAY & FEED CO. OWNS AN ALFALFA PROCESSING PLANT APPROXIMATELY ONE MILE WEST OF GAYVILLE, S. D. SOUTH DAKOTA SIP REGULATION ARSD 74:26:03:05 PROHIBITS ANY PERSON OPERATING AN ALFLAFA PELLETIZING OR DEHYDRATING FACILITY FROM DISCHARGING INTO THE AMBIENT AIR ANY AIR CONTAMINANT OF A SHADE OR DENSITY EQUAL TO OR DARKER THAN ... THIRTY PERCENT OPACITY. TWO VIOLATIONS WERE OBSERVED BY THE S. D. DEPT. OF ENVIR. PROTECTION, JULY 18, 1983 - 69% OPACITY SEPTEMBER 21, 1983 - 57% OPACITY. REGION 8 ISSUED A SECTION 120 NON ON 06-11-84. ON FEBRUARY 28,1985, MIKE RISNER OF REGION 8 SENT EPA HQ A SAMPLE CONSENT AGREEMENT WHICH HE PROPOSED WOULD ADEQUATELY SETTLE ALL FIVE OF THE REGION 8 ALFALFA CASE: JENSEN BROTHERS, NATIONAL ALFALFA, SIOUX ALFALFA, BARNES HAY AND FEED, AND MILLBANK ALFALFA. HQ RESPONDED AT THE END OF MARCH, 1985, STATING THAT THERE WERE ONLY TWO EXPLICIT WAYS OF SETTLING A SECTION 120 PROCEEDING SHORT OF OBTAINING THE FULL ECONOMIC BENEFIT PENALTY, EITHER THROUGH WITHDRAWL OR MODIFICATION OF THE NON BECAUSE THE SOURCE IS NOT IN VIOLATION OR IS ENTITLED TO AN EXEMPTION UNDER 40 C. F. R. SECTIONS 66.31-66.33. HQ RESPONDED THAT THE PROPOSED CONSENT AGREEMENT WAS INADEQUATE. REGION 8 AND AED AND SSCD PARTICIPAT