The Alluvial Tracer Complex (ATC) project has been underway since June 2000.  Nye County is working on the ATC project with the U.S. Department of Energy (DOE), U.S. Geological Survey (USGS), Los Alamos National Laboratory, University of Nevada Las Vegas, and the Yucca Mountain Site Characterization Project Office M&O. The ATC was implemented to characterize the hydraulic properties of the alluvium down-gradient of the Yucca Mountain site. 

 

Nye County drilled the wells (NC-EWDP-19D and -19P) during the EWDP Phase II drilling effort. NC-EWDP-19P was drilled in March 2000 to a depth of 499.2 feet. NC-EWDP-19P is one of the monitoring wells that is located approximately twenty-five (25) meters northeast of NC-EWDP-19D.   In April 2000, NC-EWDP-19D was drilled to a depth of 1456.25 feet.  It is the pump well for single well tracer testing.

 

During the first phase of the project, four other EWDP wells were monitored during the single well pump/injection tests (NC-EWDP-4PA, -4PB, -15P, and Washburn-1x).  In June 2000, test equipment was installed at the site by Nye County. In July 2000 the USGS conducted the first test.  To date, one open-hole pump test and four closed interval hydraulic tests have been performed by the USGS.  Also, a gravity meter survey was conducted in late September 2000.   Single well tracer tests began in late November 2000 and continued into July 2001.  NC-EWDP-19IM1 and NC-EWDP-19IM2 were drilled in July 2001 to serve as the cross-hole injection and monitoring wells.  NC-EWDP-19IM1 was instrumented with a Westbay monitoring system in October 2001 by Nye County and NC-EWDP-19IM2 was instrumented with Baski and Parascientific monitoring equipment in December 2001 by Nye County and the USGS.  Cross-hole testing at the complex has been put on hold pending approval of DOE water pumping and injection permits.