THE VIOLATION(S) UPON WHICH THE ACTION IS BASED. THE MENTOR CORPORATION SITE IS CONTAINED WITHIN OPERABLE UNIT X OF THE DENVER RADIUM SUPERFUND SITE. THE SITE COVERS APPROXIMATELY 17.5 ACRES OF LAND WITHIN THE DENVER METROPOLITAN AREA. THE HAZARDOUS SUBSTANCES OF CONCERN THAT HAVE BEEN RELEASED AT THE SITE ARE RADIUM AND ITS ASSOCIATED RADIOACTIVE DECAY PRODUCTS. THE ESTIMATED 4,000 CUBIC YARDS OF RADIUM CONTAMINATED SOILS AT THE SITE CONSTITUTE A POTENTIAL THREAT TO PUBLIC HEALTH, WELFARE, AND THE ENVIRON- MENT THROUGH THE RELEASE AND THREATENED RELEASE OF RADIUM AND ITS DECAY PRODUCTS INTO THE SOIL AND AIR. EPA HAS INCURRED AND IS INCURRING RESPONSE COSTS NOT INCONSISTENT WITH THE NATIONAL CONTINGENCY PLAN TO CONDUCT A REMEDIAL INVESTIGATION AND FEASIBILITY STUDY FOR THE SITE. EPA WILL INCUR FUTURE RESPONSE COSTS IN UNDERTAKING THE DESIGN AND IMPLEMENTATION OF REMEDIAL ACTION FOR THE SITE. ACTION IS BASED UPON SECTIONS 104(A), 106(A), AND 107(A) OF CERCLA, 42 USC 9604(A), 9606(A), RESPECTIVELY. THE PROPOSED RELIEF TO BE SOUGHT, INCLUDING INJUNCTION, AND PROPOSED AMOUNT OF PENALTY TO BE SOUGHT AT SETTLE- MENT, IF APPLICABLE. INJUNCTIVE RELIEF REQUIRING THE DEFENDANT TO PROVIDE CONTINUING ACCESS TO ITS PROPERTY TO ALLOW EPA TO UNDERTAKE REMEDIAL ACTION SHOULD BE OBTAINED. FURTHER, INJUNCTIVE RELIEF SHOULD BE OBTAINED REQUIRING DEFENDANT TO MAKE AVAILABLE A CERTAIN PORT