THE MARINA CLIFFS SITE CURRENTLY OCCUPIES ROUGHLY 13 ACRES OF VACANT LAND SOUTH OF DREXEL STREET AND EAST OF FIFTH AVENUE ALONG LAKE MICHIGAN IN SOUTH MILWAUKEE, WISCONSIN. FROM 1941 THROUGH THE MID-1960S, NORTHWESTERN BARREL DUMPED, WASHED, RECYCLED AND RECONDITIONED BARRELS AT THE SITE. AS A RESULT OF THOSE OPERATIONS, THE SITE BECAME CONTAMINATED WITH HAZARDOUS SUBSTANCES INCLUDING POLYCHLORINATED BIPHEN- YLS ( PCBS ), VOLATILE ORGANIC COMPOUNDS ( VOCX ), PAINT WASTES, CHROMIUM, LEAD, AND OTHER HEAVY METALS. DRUMS, BARRELS, AND DEBRIS WERE ABANDONED IN THE RAVINE AND LAKE BLUFF AREAS OF THE SITE. THE AREA AROUND THE SITE IS HEAVILY POPULATED. IT IS BORDERED ON THE SOUTH AND WEST SIDES BY RESIDENTIAL AREAS (MOSTLY APARTMENTS AND CONDOMINIUMS), ON THE EAST BY LAKE MICHIGAN, AND ON THE NORTH BY SOUTH MILWAUKEE WASTE WATER TREATMENT PLANT IS APPROXIMATELY THREE-QUARTERS OF A MILE OFF-SHORE FROM THE SITE. THE SITE IS NOT ON THE NATIONAL PRIORITIES LIST. ON OCTOBER 3, 1995, U.S. EPA ISSUED A UNILATER ADMINISTRA- TIVE ORDER ( 1995 UAO ) TO THE CURRENT OWNERS OF THE SITE AND TO 78 OF THE LARGEST GENERATORS OF MATERIALS DISPOSED OF AT THE SITE. UNDER THAT UAO, A GROUP OF THE GENERATOR PRPS (THE PRP GROUP ) EXCAVATED, STOCKPILED AND DISPOSED OF MORE THAN 10,000 TONS OF CONTAMINATED SOILD AND SLUDGE FROM DISPOSAL PIT AREAS, ALONG WITH MORE