CX-270039: Test Reactor Area (TRA)-715 Evaporation Pond Liner Replacement

The hypalon liner for the TRA-715 Evaporation Pond has reached the end of its service life and a new liner is needed.  The installation would be started in calendar year 2015 and completed in 2016.  In order to install the new liner, the west side of the pond would be drained first.  To drain the pond, a temporary system would be used to pump water through perforated pipe along the upper slope of the pond so it flows down the liner into the pond, increasing the evaporation rate.  Low-level wastewater from the evaporation pond would be shipped to the Idaho Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Disposal Facility pond.  Residual sludge and debris would be removed from the pond, boxed in waste containers, and shipped for disposal.  The new liner would be installed over the old liner to reduce the spread of contamination that could occur from removal of the old liner.  A layer of geotextile would be installed over the old liner to reduce the spread of radioactive contamination and to prevent damage to the old liner during installation of new layers.  The new liner would be placed over the geotextile and anchored with fill along the edges after it is stretched over a new berm of sandbags.