ON 1/5/86, A STORAGE TANK CONTAINING DICHLOROBENZENE(DCB) EXPLOSIVELY RUPUTURED. THE RELEASE OF DCB DAMAGED 3 ADDI- IONAL TANKS W/THE RESULT THAT OVER 400,000 GALLONS OF THE CHEMICAL WAS RELEASED, MUCH OF IT ENTERING AN UNNAMED CREEK, A TIDAL MARSH & RED LION CREEK. AN EPA INSPECTOR WAS ON SITE & PHOTOGRAPHED THE SPILL ON 1/5-6/86. DEF HAS SINCE REPORTED TO EPA THAT THE MATERIAL SPILLED AT THEIR FACILITY WAS IN FACT DCB, A DESIGNATED HAZARDOUS SUB- STSANCE, AND THAT THE VOLUME SPILLED WAS GREATLY IN EXCESS OF THE 100 LB QUANITY DESIGNATED IN 40 CFR SEC 117.3 AS GIV- ING RISE TO LIABILITY UNDER SEC 311 OF CWA. BECAUSE OF THE SIZE & NATURE OF THE SPILL, THE COAST GUARD REFERRED THIS CASE TO EPA RATHER THAN PROCEEDING AD- MINISTRATIVELY. REG 3 PROPOSES ONLY A SEC 311 ACTION, AS THE COMPANY'S CLEAN-UP EFFORTS APPEAR PRESENTLY TO BE PROCEEDING SATISFACTORILY, ALBEIT SLOWLY. SHOULD FUTURE INJUNCTIVE RE- LIEF BECOMES NECESSARY, THE REGION WOULD RECOMMEND AN ACTION UNDER SEC 309 OF CWA OR SEC 106 OF CERCLA.