High Hazard Systems Decontamination & Decommissioning

The DDES team completed decontamination and decommissioning of the High Hazard Process Systems and associated surfaces at Nuclear Metals, Inc. Superfund Site in Concord, Massachusetts. Under this scope DDES developed the decontamination and neutralization procedures for systems which contained concentrated hydrofluoric acid, sulfuric acid, hydrochloric acid, hydrogen peroxide, sodium hydroxide and depleted uranium. DDES was awarded this work after the previous contactor had a metals fire. These process decommissioned include the Pickling Area in Building D, and the Acid Recycling Area, as well as the decommissioning of the Hydrogen Peroxide System.

Each of these process areas required the development of specific LOTO and line breaking procedures to assure the corrosive radioactive liquids were appropriately controlled. Specialized personnel decontamination and first-aid procedures were developed by DDES to address the significant hazard presented by hydrofluoric acid. DDES employed color changing neutralization agents to identify where equipment and surfaces had been impacted by hydrofluoric acid, sulfuric acid, hydrochloric acid and sodium hydroxide residues. The impacted process piping, pumps, tanks and air scrubbing equipment were treated with buffered neutralization agents to achieve a neutral pH so these materials could be disposed of as non-hazardous dry active waste (DAW). A total of five pickling dip tanks, two electroplating tanks four process tanks, and a caustic scrubber system were disassembled, size reduced, and neutralized under this scope of work.