7.  Agencies Studying Water Chemistry Now, Part A

Knowledge of the regional ground water characteristics stems largely from four sources: 

1. Studies conducted by the United States Geological Survey (USGS),
2. NTS studies (Atomic Energy Agency, US Department of Energy, Nevada Operations, National Nuclear Security Agency, Nevada)[1],
3. US Department of Energy, Yucca Mountain Project[2], and
4. Nye County Early Warning Drilling Program.[3]

7.1  The United States Geological Survey (USGS)

The USGS has conducted a number of groundwater studies in the vicinity of the study area. Those that were most useful in preparing this report include: studies by Laczniak et al. on the springs at Ash Meadows and groundwater flow at the NTS (Laczniak et al., 1996 & 1999); groundwater modeling studies of the DVRFS by Belcher et al, (Belcher et al, 2002 & 2004); and studies conducted in the vicinity of US Ecology’s hazardous waste facility by personnel of the Amargosa Desert Research Site (Striegl et al., 1997).

7.2  Nevada Test Site Studies

Studies at the NTS were conducted by a variety of NTS contractors over the years of test site operations.  However, the first formal work began around 1972 with the EPA’s Long Term Hydrological Monitoring Program (LTHMP), which had four major objectives:

1. assure public safety,
2. document compliance with standards and regulations,
3. detect the migration of radioactivity,
4. disseminate information to the public, news media, and scientific community. [4]  

Thus, many wells were drilled to facilitate long-term monitoring and better understanding of groundwater contamination.  As of 1996, LTHMP routinely monitored only 21 wells on the NTS, and just 12 wells, 9 springs, and one water body off the NTS.  Figures 7.2.1 and 7.2.2 show monitoring locations as of 2003.  However, none of the 12 off-site wells as of 2002 were designed to be monitoring wells.  Consideration of these wells was based on “point of opportunity” and not upon judicious selection for detection of contamination for point of compliance and/or early warning.[5]  The general paradigm of thought at the NTS has been that groundwater moves very slowly, and that radionuclides have remained in the near field of the underground test cavities, thus remaining on-site of the NTS.

7.3  The Underground Test Area Program (UGTA)

In 1989 the Department of Energy Environmental Management (DOE/EM) Nevada Operations Office created the Underground Test Area Program (UGTA). According to Mr. Carl Gertz, then assistant manager of the DOE/EM program for the NTS, it was “established to evaluate the extent of contamination in the groundwater due to underground weapons testing.”  Certainly, the potential for contamination at the NTS is considerable; during the forty years of nuclear weapons testing there were some 921 underground nuclear explosions, releasing an estimated 300 million curies of radioactivity. [6] 

While the stated goal of the UGTA is to understand the extent of contamination, most of the effort has been to develop a regional groundwater model.  This has been criticized for insufficient hard well data to substantiate details of the model.[7]  In general, groundwater movements can only be understood with confidence on a gross scale.  Further, according to the Citizen Alert report, the early warning system in place by NNSA/NV (then DOE/NV) may not be strategically sited to maximize radionuclide detection.  This is of particular concern because, as stated in Section 5.1, the potential exists for tritium to have reached off-site locations.  It also reinforces the need for a detailed and ongoing regimen of water testing.

Figure 7.2.1. Routine Radiological Environmental Monitoring Plan (2003)

Groundwater monitoring locations on and off the NTS.

Source: Annual Site Environmental Report for the Nevada Test Site, 2003.

Figure 7.2.2.  Wells recently drilled or sampled for the UGTA Project.

Source: Annual Site Environmental Report for the Nevada Test Site, 2003, pg 3-16.

Figure 7.3. Yucca Mountain Site Investigation Area

Showing Location of the Surface-Based and Underground Test Facilities at Yucca Mountain,

Including Boreholes and Underground Excavation.

(Source: DOE Yucca Mountain Science and Engineering Report, pg. 1-17)