National Emission Standards for Hazardous Air Pollutants Calendar Year 2001; TOPICAL

The Nevada Test Site (NTS) is operated by the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Operations Office (NNSA/NV) as the site for nuclear weapons testing, now limited to readiness activities, experiments in support of the national Stockpile Stewardship Program, and the activities listed below. Located in Nye County, Nevada, the site's southeast corner is about 88 km (55 mi) northwest of the major population center, Las Vegas, Nevada. The NTS covers about 3,561 km2 (1,375 mi2), an area larger than Rhode Island. Its size is 46 to 56 km (28 to 35 mi) east to west and from 64 to 88 km (40 to 55 mi) north to south. The NTS is surrounded, except on the south side, by public exclusion areas (Nellis Air Force Range[NAFR]) that provide another 24 to 104 km (15 to 65 mi) between the NTS and public lands (Figure 1.0). The NTS is characterized by desert valley and Great Basin mountain topography, with a climate, flora, and fauna typical of the southwest deserts. Population density within 150 km (93 mi) of the NTS is only about 0.2 persons per square kilometer, excluding the Las Vegas area. Restricted access, low population density in the surrounding area, and extended wind transport times are advantageous factors for the activities conducted at the NTS. Surface waters are scarce on the NTS, and slow-moving groundwater is present hundreds to thousands of feet below the land surface. The sources of radionuclides include current and previous activities conducted on the NTS (Figure 2.0). The NTS was the primary location for testing of nuclear explosives in the Continental U.S. between 1951 and 1992. Historical testing above or at ground surface has included (1) atmospheric testing in the 1950s and early 1960s, (2) earth-cratering experiments, and (3) open-air nuclear reactor and rocket engine testing. Since the mid-1950s, testing of nuclear explosive devices has occurred underground in drilled vertical holes or in mined tunnels (DOE 1996a). No such tests have been conducted since September 23, 1992 (DOE 2000). Limited non-nuclear testing includes spills of hazardous materials at the Hazardous Materials Spill Center, private technology development, aerospace and demilitarization activities, and site remediating activities. Processing of radioactive materials is limited to laboratory analyses, and handling is restricted to transport, storage, and assembly of nuclear explosive devices and operation of radioactive waste management sites (RWMSs) for low-level radioactive and mixed waste (DOE 1996a). Monitoring and evaluation of the various activities conducted onsite indicate that the potential sources of offsite radiation exposure in CY 2001 were releases from (1) evaporation of tritiated water (HTO) from containment ponds that receive drainage water from E Tunnel in Area 12 and from discharges of two wells (Well U-3cn PS No. 2 and Well ER-20-5 No.3) into lined ponds, (2) onsite radio analytical laboratories, (3) the Area 5 RWMS (RWMS-5) facility, and (4) diffuse sources of tritium and re- suspension of plutonium and americium. The following sections present a general description of the present sources on the NTS and at the North Las Vegas Facility