Nevada Test Site

Environmental Report 2004

Summary

DOE/NV/1

J2006
 

 

Disclaimer

Reference herein to any specifi c commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof or its contractors or subcontractors.

This report was prepared for:

U. S. Department of Energy

National Nuclear Security Administration

 Nevada Site Offi ce

 under Contract DE-AC08-96NV11718

 by: 

Bechtel Nevada 

Post Offi ce Box 98521 

Las Vegas, NV 89193-8521

The information presented in this document is explained in greater detail in the Nevada Test Site Environmental Report 2004 (DOE/NV/11718—1080). It can be downloaded from the NNSA/NSO website at 

http://www.nv.doe.gov/library/publications/environmental.aspx or from the U. S. Department of Energy 

Offi ce of Scientifi c and Technical Information at http://www.osti.gov/bridge.
1

 

 

Report Objectives

Present results of environmental monitoring of radiological and nonradiological 

effl uents 

Report estimated potential 

radiological doses to the 

public from releases of 

radioactive material 

Report compliance status 

with environmental standards and requirements

Summarize environmental 

incidents of noncompliance 

and actions taken in response to them 

Highlight signifi cant environmental programs and efforts

Nevada Test Site 

Environmental Report 2004 Summary

This document is a summary of the Nevada Test Site Environmental Report 

(NTSER) for calendar year 2004, a comprehensive presentation of environmental 

monitoring and compliance activities performed at the Nevada Test Site (NTS) 

throughout the previous calendar year. It is prepared annually to meet the 

requirements and guidelines of the U.S. Department of Energy (DOE) and the information needs 

of the public, including government offi cials, regulatory authorities, NTS contractors, and all others 

with an interest in the NTS. 

This summary document satisfi es the NTSER objectives but does not include detailed data 

tables, monitoring methods or design, a description of the NTS environment, or a discussion of 

all environmental program activities performed throughout the year. The reader may obtain a 

hardcopy or compact disc of the full report as directed on the inside front cover of this summary. 

The U.S. Department of Energy, National Nuclear Security 

Administration Nevada Site Offi ce (NNSA/NSO) directs the 

management and operation of the NTS. The NTS is located 

about 65 miles northwest of Las Vegas. The approximately 1,375 

square mile site is one of the largest restricted access areas in the 

United States. It is surrounded by federal installations with strictly 

controlled access as well as by lands that are open to public entry. 
 

 

2 

NTS History

The history of the NTS and its current missions 

direct the focus and design of the environmental 

monitoring and surveillance activities on and near the 

site. Between 1940 and 1950, the area now known 

as the NTS was part of the Nellis Bombing and 

Gunnery Range. In 1950, the NTS was established to 

be the primary location for testing the nation’s nuclear 

explosive devices, which took place from 1951 to 1992. 

The NTS currently conducts only subcritical nuclear 

experiments. 

Tests conducted 

through the 

1950s were 

predominantly 

atmospheric tests. 

These involved a 

nuclear explosive 

device detonated 

while on the 

ground surface, 

on a steel tower, 

suspended from 

tethered balloons, 

dropped from 

an aircraft, or placed on a rocket. Several tests were 

categorized as "safety experiments" and "storagetransportation tests," involving the destruction of a 

nuclear device with non-nuclear explosives. Some of 

these tests resulted in dispersion of plutonium in the 

test vicinity. One of these test areas (Project 57) lies 

just north of the NTS boundary on the Nevada Test 

and Training Range (NTTR) (formerly known as the 

Nellis Air Force Range). Other tests, involving storage 

transportation, were conducted at the north end of 

the NTTR (Double Tracks) and on the Tonopah Test 

Range (TTR) (Clean Slates I, II, and III). All nuclear 

device tests are listed in United States Nuclear Tests, July 

1945 through September 1992.

1

The fi rst 

underground test, 

a cratering test, 

was conducted in 

1951. The fi rst 

totally-contained 

underground 

test was in 1957. 

Testing was 

discontinued 

during a 

moratorium 

that began October 31, 1958, but was resumed in 

September 1961 after tests by the Union of Soviet 

Socialist Republics began. Since late 1962, nearly 

all tests have been conducted in sealed vertical 

shafts drilled into Yucca Flat and Pahute Mesa or in 

horizontal tunnels mined into Rainier Mesa. From 

1951 to 1992, a total of 828 underground nuclear 

tests were conducted at the NTS. Approximately 

one third of these tests were detonated near or below 

the water table and has resulted in the contamination 

of groundwater in some areas. In 1996, DOE, U.S. 

Department of Defense (DoD), and the state of 

Nevada entered into a Federal Facilities Agreement 

and Consent Order (FFACO) which established 

Corrective Action Units (CAUs) on the NTS 

that delineated and defi ned areas of concern for 

groundwater contamination. 

Five earthcratering 

(shallow-burial) 

tests were 

conducted over 

the period of 

1962 through 

1968 as part of 

the Plowshare 

Program 

that explored 

peaceful uses 

of nuclear 

explosives. The 

fi rst and highest yield Plowshare crater test, Sedan, 

was detonated at the northern end of Yucca Flat on 

the NTS. The second highest yield crater test was 

Schooner, located in the northwest corner of the 

NTS. Mixed fi ssion products, tritium, and plutonium 

from these tests were entrained in the soil, ejected 

from the craters, and deposited on the ground 

surrounding the craters. 

Other nuclear-related experiments at the NTS 

included the Bare Reactor Experiment - Nevada 

series in the 1960s. These tests were performed 

with a 14 million electron volt neutron generator 

mounted on a 1,527-foot steel tower used to conduct 

neutron and gamma-ray interaction studies on various 

materials. In addition, from 1959 through 1973 a 

series of open-air nuclear reactor, nuclear engine, and 

nuclear furnace tests were conducted in Area 25, and 

a series of tests with a nuclear ramjet engine were 

conducted in Area 26. Mostly gaseous radioactivity 

(radio-iodines, radio-xenons, radio-kryptons) and 

some fuel particles were released due to erosion of 

the metal cladding on the reactor fuel; these releases 

resulted in negligible deposition on the ground.

1 U.S. Department of Energy, 2000. Report No. DOE/NV-209 

(Rev. 15).

Detonation of Priscilla, 

June 24, 1957

Underground test location, 

Yucca Flat, 1987

Sedan, Plowshare Program, 

July 6, 1962
 

 

NTS Missions and

Their Programs

National Security

Stockpile Stewardship Program – Conducts highhazard operations in support of defense-related 

nuclear and national security experiments. 

Homeland Security Program – Provides support 

facilities, training facilities, and capabilities for 

government agencies involved in counterterrorism 

activities, emergency response, first responders, 

national security technology development, and 

nonproliferation technology development. 

Test Readiness Program – Maintains the capability to resume underground nuclear weapons 

testing, if directed. 

Environmental Management

Environmental Restoration Program – 

Characterizes and remediates the environmental 

legacy of nuclear weapons and other testing at 

the NTS and offsite locations and develops and 

deploys technologies that enhance environmental 

restoration. 

Waste Management Program – Manages and 

safely disposes of low-level waste received from 

DOE- and U.S. Department of Defense-approved 

facilities throughout the United States and mixed 

low-level waste generated in Nevada by 

NNSA/NSO, and safely manages and 

characterizes hazardous and transuranic wastes 

for offsite disposal.

Stewardship of the NTS

Facilities and Infrastructure – Maintains the 

buildings, roads, utilities, and facilities required to 

support all NTS programs and to provide a safe 

environment for NTS workers.

3

NTS Mission

Los Alamos, Lawrence Livermore, and Sandia National Laboratories are the principal organizations 

that sponsor and implement experimental programs 

at the NTS. Bechtel Nevada (BN) is the Management 

and Operations (M&O) contractor accountable for 

the successful execution of work and ensuring that 

work is performed in compliance with environmental 

regulations. The three major NTS missions include 

National Security, Environmental Management, and 

Stewardship of the NTS. During the conduct of all 

missions and their programs, NNSA/NSO complies 

with applicable environmental and public health protection regulations and strives to manage the land and 

facilities at the NTS as a unique and valuable national 

resource.

NTS activities in 2004 continue to be diverse, 

with the primary role being to help ensure that 

the existing United States stockpile of nuclear 

weapons remains safe and reliable. Facilities that 

support this mission include the U1a Facility, the 

Big Explosives Experimental Facility (BEEF), the 

Device Assembly Facility (DAF), and the Joint 

Actinide Shock Physics Experimental Research 

(JASPER) Facility. Other NTS activities include 

demilitarization activities, controlled spills of 

hazardous material at the Non-Proliferation Test 

and Evaluation Complex (NPTEC) (formerly 

known as the Hazardous Materials Spill Center), 

remediation of industrial sites, processing of waste 

destined for the Waste Isolation Pilot Plant in 

Carlsbad, New Mexico, disposal of radioactive and 

mixed waste, and environmental research. 

Radiation Monitoring 

The release of man-made radionuclides from the 

NTS has been monitored since the fi rst decade of 

atmospheric testing. After 1962 when nuclear tests 

were conducted only underground, the radiation 

exposure to the public surrounding the NTS was 

greatly reduced. Underground nuclear testing nearly 

eliminated atmospheric releases of radiation, but 

resulted in the contamination of groundwater in 

some areas of the NTS. After the 1992 moratorium 

on nuclear testing, radiation monitoring focused on 

detecting airborne radionuclides that are resuspended 

with historically-contaminated soils on the NTS and 

on detecting man-made radionuclides in groundwater. 

Radionuclides produced on the NTS have never 

been detected in drinking water samples offsite, and 

resuspended soils from the NTS are indistinguishable 

from global fallout measured in air samples. Since 

1992, radiation doses to the public from NTS activities 

were estimated to be less than 0.15% of doses from 

background radiation. 
 

 

4 

Pathways of Radiation Exposure to 

the Public from NTS Activities 

Radiation may be found everywhere. Almost all 

radiation exposure comes from natural sources (82% 

in the United States). These sources include cosmic 

radiation from outer space, terrestrial radiation 

from materials like uranium and radium in the 

earth, and naturally-occurring radioactive elements 

(i.e., radionuclides) in our food, water, and the 

aerosols and gases in the air we breathe. Exposures 

to man-made radiation in our every-day life come 

from smoking cigarettes, traveling on airplanes, and 

having medical x-rays. For the public surrounding 

the NTS, only a very small amount of their total 

radiation exposure may be attributable to past or 

current NTS activities. 

There are three pathways in this dry desert 

environment by which man-made radionuclides 

from the NTS might reach the surrounding public. 

One is inhalation of particulates or water vapor 

containing radionuclides that are resuspended by the 

wind from known contaminated sites (legacy sites) 

on the NTS. Such resuspended radiation measured 

off and on the NTS is much lower than natural 

background radiation in all areas accessible to the 

public. The second possible, but unlikely, pathway 

is ingestion of game animals that have been exposed 

to contaminated soil or water on the NTS and then 

move off the NTS and are hunted. A third pathway 

of exposure, drinking contaminated groundwater, is 

currently not a possible pathway for public exposure 

given the restricted public access to the NTS and 

the location of known contaminated groundwater 

on the NTS. No man-made radionuclides occur 

in drinking water sources monitored off the NTS 

and no drinking water wells on the NTS have 

measurable levels of man-made radionuclides. Only 

the groundwater from monitoring wells drilled near 

underground tests on the NTS show radioactive 

contamination. 

In 2004, the public dose from NTS activities from 

all pathways was estimated to be 0.51 mrem/

yr. This is about 0.15 percent of the dose from 

natural background radiation. The remainder of 

this report summarizes the results of radiological 

monitoring conducted in 2004 (pages 5-16) and 

how the public radiation dose was calculated (pages 

17-19). Non-radiological monitoring results and 

other environmental program activities in 2004 are 

summarized also (pages 20 – 24).

Potential Dose Pathways to the Public
 

 

5

Off site Radiological Air Emissions

An important component of the NTS radiological 

monitoring program is an oversight monitoring 

program run by an organization independent of 

the M&O contractor. It can independently confi rm 

compliance with radiological air emission and water 

quality standards offsite. This oversight monitoring 

is performed under the Community Environmental 

Monitoring Program (CEMP), which is coordinated by 

the Desert Research Institute (DRI) of the University 

and Community College System of Nevada under 

contract with NNSA/NSO. Its purpose is to provide 

monitoring for radionuclides which may be released 

from the NTS. A network of 26 CEMP stations 

located in selected towns and communities within 

240 miles from the NTS was operated continuously 

during 2004 (see map on following page). The 

CEMP stations monitored gross alpha and beta 

radioactivity in airborne particulates using low-volume 

particulate air samplers, penetrating gamma radiation 

using thermoluminescent dosimeters (TLDs), 

gamma radiation exposure rates using pressurized 

ion chamber (PIC) detectors, and meteorological 

parameters using automated weather instrumentation 

(MET stations). 

No airborne radioactivity related to any NTS 

operations was detected in any of the CEMP samples 

during 2004. Gross alpha and gross beta radioactivity 

was detected at all CEMP stations at levels consistent 

with previous years, which refl ect radioactivity from 

background radiation. No man-made gamma-emitting 

radionuclides were detected. Naturally-occurring 

radioactive beryllium (7

Be) was detected in most air 

particulate samples. 

The TLD and PIC detectors can measure gamma 

radiation from all sources, both natural background 

radiation from cosmic and terrestrial sources and 

radiation from man-made sources. The offsite TLD 

and PIC results remained consistent with previous 

years’ background levels and are well within average 

background levels observed in other parts of the 

United States. The highest total annual gamma 

exposure measured offsite, based on the PIC 

detectors, was 178 milliroentgen (mR) at Milford, 

Utah (at 4,957 feet above seal level; compare with 

Denver, Colorado at 5,193 feet above sea level, with 

an annual exposure of 165 mR). The lowest offsite 

Average Background Radiation of Selected 

U.S. Cities (Excluding Radon)

City

Radiation Exposure 

(mR/yr)

Denver, Colorado

Fort Worth, Texas

Los Angeles, California

New Orleans, Louisiana

Portland, Oregon

Richmond, Virginia

Rochester, New York

St. Louis, Missouri

Tampa, Florida

Wheeling, West Virginia

164.6

68.7

73.6

63.7

86.7

64.1

88.1

87.9

63.7

111.9

Source: < http://www.wrcc.dri.edu/cemp/Radiation.html>

 “Radiation in Perspective,” August 1990, as accessed on 

3/22/2005

Las Vegas CEMP Air Monitoring Station

(photo by Lynn Karr, October 2004)

Forms of Radiation

Alpha – heavy, positively charged particles given off 

by atoms of elements such as uranium. These can 

simply be washed off the skin. They can be blocked 

by a sheet of paper. They enter the body through 

cuts, mouth, or nose.

Beta – consists of electrons or positrons (positively 

charged electrons). More penetrating than alpha 

radiation, beta electrons can pass through several 

millimeters of skin. A sheet of aluminum only a 

fraction of an inch thick will stop beta radiation.

Gamma – a very penetrating form of electromagnetic 

radiation, similar to x-rays, light, and radiowaves. 

These can readily pass into the human body. They 

can be almost completely blocked by about 40 inches 

of concrete, 40 feet of water, or a few inches of lead.

X-rays – a more familiar form of electromagnetic 

radiation, usually with a limited penetrating power, 

typically used in medical or dental examinations. 

Television sets, especially color, give off soft (low 

energy) x-rays; thus, they are shielded to greatly 

reduce the risk of radiation exposure.

Neutrons – uncharged heavy particles contained 

in the nucleus of every atom heavier than ordinary 

hydrogen. They induce ionization only indirectly 

in atoms which they strike, but can damage body 

tissues. Neutrons are released, for example, during 

the fission (splitting) of uranium atoms in the fuel 

of nuclear power plants. They can also be very 

penetrating. In general, efficient shielding against 

neutrons can be provided by water.
 

 

6 

gamma exposure rate measured was 67 mR per year at 

Pahrump, Nevada. 

Onsite Radiological Air Emissions

The potential for radioactive air emissions on the NTS 

is due to operations involving radioactive materials and 

to legacy soil contamination from past nuclear tests. 

Therefore, continuous onsite radiological sampling of 

air is conducted and reported annually by BN to assure 

the public and regulatory agencies that the emissions 

are safe and in compliance with state and federal 

regulations. A network of 19 air sampling stations (3 

having low-volume particulate air samplers, 1 having a 

tritium water vapor sampler, and 15 having both) and 

a network of 107 TLDs were used to monitor NTS 

radioactive emissions in 2004 (see map on page 8). Air 

sampling stations and TLDs are placed throughout 

the NTS, mainly within those numbered Operational 

Areas where historic nuclear testing has occurred or 

where current radiological operations occur. The 

2004 monitoring results were also used, in conjunction 

with U.S. Environmental Protection Agency (EPA)-

approved mathematical models, to calculate the 

radiological dose to the public residing within 50 miles 

of the NTS (see page 17).

The modeling results indicate that there were 

minimal radioactive air emissions from current NTS 

activities in 2004, which came from only one NTS 

facility. A total of 0.000042 Curies (Ci) of tritium gas 

was released at Building 650 (in Mercury, Area 23) 

during the calibration of laboratory equipment. 

No radioactivity was detected above minimum 

detectable concentrations (MDCs) in any of the 

samples collected from the JASPER Facility stack. 

No radiological releases occurred at U-1a, BEEF, or 

DAF, and no increasing trends in the concentrations 

of man-made radionuclides were detected from air 

samples collected nearest these facilities. 

Background gamma radiation exposure rates on the 

NTS, measured at TLD stations located away from 

radiologically contaminated sites, ranged from 60 to 

156 mR/yr during 2004. Direct gamma radiation 

exposure to the public from NTS operations was 

negligible. Areas accessible to the public (such as the 

NTS entrance gate) had exposure rates which were 

equal to natural background rates, with one exception. 

During the fourth quarter of 2004, the daily average 

gamma radiation exposure rate measured on the west 

side of the parking area outside the NTS entrance 

2004 CEMP Air Surveillance Network
 

 

7

Potential Sources of Radiological Air Emissions on the NTS
 

 

8 

2004 NTS Air Sampling Network
 

 

9

gate rose to 358 mR/yr, up from 73, 77, and 113 

mR/yr during the fi rst, second, and third quarters, 

respectively. It is likely that low-level radioactive waste 

shipments entering the NTS were responsible for this 

increase during the fourth quarter. 

Radionuclide contamination at legacy sites has resulted 

in localized elevated gamma exposure rates, but the 

public has no access to these sites nor are there NTS 

personnel working in these areas. As in previous years, 

the highest exposure rate at monitored locations was 

863 mR/yr at Schooner, one of the legacy Plowshare 

sites on Pahute Mesa. The 16 TLD stations that 

monitor the Area 3 RWMS and the Area 5 RWMC 

showed a mean gamma exposure rate of 148 mR/yr 

and ranged from 106 to 401 mR/yr. The public are 

not allowed unsupervised access to these sites.

Gross alpha and gross beta radioactivity were detected 

at all stations on the NTS, but no increasing trend in 

levels of radioactivity was observed at any station. 

The highest average gross alpha and gross beta 

activities were seen at Sugar Bunker, an unoccupied 

structure used during past nuclear testing, located 

about 0.6 miles south-southwest of the Area 5 

RWMC. The lowest average gross alpha and beta 

activities were measured at the Little Feller 2 and 3545 

Substation samplers, respectively. The Little Feller 2 

air sampler is in Area 18, 0.1 miles northwest of the 

Little Feller 2 site, where an above-ground nuclear 

test was conducted for the development of a nuclear 

warhead for the Davy Crockett rocket launcher. 

The 3545 Substation is in the lower half of Area 16 

in the center of the NTS. The mean gross alpha 

concentrations were slightly higher at the locations 

near sites with known deposits of radioactivity from 

past nuclear tests in Areas 1, 3, 5, 6, 9, 10, and 20. 

The mean gross beta concentrations varied less by 

location throughout all NTS areas. Both the weekly 

gross alpha and gross beta concentrations continued 

to show a general temporal variation that was common 

for all locations. 

Several man-made radionuclides were measured 

in air samples at levels above their MDCs in 2004: 

americium-241 (241Am), tritium (3H), plutonium-238 

(

238Pu), and plutonium-238+239 (239+240Pu). These 

"detects" were all attributed to the resuspension of 

contamination in surface soils from legacy sites and to 

the evaporation and transpiration of tritium from the 

soil, plants, and containment ponds at legacy sites. 

Range in Radioactivity/Radiation Levels

Measured at Offsite and Onsite Air Sampling Stations

Average Gross Alpha

(x 10-15 μCi/mL)

Average Gross Beta

(x 10-14 μCi/mL)

Total Gamma

 Exposure Rate (mR/yr)

Offsite Onsite Offsite Onsite Offsite Onsite

Highest 

Average 

Value

2.96

(Boulder City)

3.80

(Sugar Bunker)

2.46

(Boulder City, 

Pahrump, Sarcobatus Flats)

2.12

(Sugar Bunker)

157(a)

(Twin Springs)

178(b)

(Milford)

863(a)

(Schooner)

Lowest 

Average 

Value

1.11

(Nyala Ranch)

1.57

(Little Feller 2)

1.85

(Ely)

1.75

(3545 Substation)

81(a)

(Pahrump)

67(b)

(Pahrump)

59(a)

(Mercury 

Fitness Track)

(a) Based on TLDs

 (b) Based on PIC detectors 

Solar Powered BN Air Monitoring Station at Schooner, 

Area 20 (photo by Terrence Sonnenburg, August 2003)
 

 

10 

All concentrations for each radionuclide were well 

below their "CL," which is the Clean Air Act National 

Emission Standards for Hazardous Air Pollutants 

(NESHAP) Concentration Level for Environmental 

Compliance. The CL is the annual average 

concentration (different for each radionuclide) that 

would result in a dose of 10 mrem/yr, the federal dose 

limit to the public from all radioactive air emissions. 

The highest levels of 241Am were detected at 

Bunker 9-300, a vacant building located within an 

area of known soil contamination from past nuclear 

tests. The highest levels of tritium were detected 

at Schooner, site of the second-largest Plowshare 

cratering experiment on the NTS, where tritiuminfused ejecta surround the crater. The highest levels 

of plutonium isotopes in air were at Bunker 9-300. 

Relatively high plutonium values occur most often at 

the Bunker 9-300 air sampling station, due to historical 

nuclear testing in Area 9 and surrounding Areas 3, 4, 

and 7. All concentrations of cesium-137 (137Cs) in the 

network were below their sample-specifi c MDCs. 

Uranium isotopes are also detected in air samples 

collected in areas where depleted uranium ordnance 

has been used or tested. However, the samples’ 

isotopic ratios were what one would expect from 

naturally-occurring uranium in soil and not from either 

man-made depleted or enriched uranium. 

Two of the most commonly detected man-made 

radionuclides, tritium and 239+240Pu, continued to show 

generally decreasing trends in concentrations at air 

sampler sites in 2004. The graphs on the next page 

show the trends in the annual mean concentrations for 

these radionuclides. Air sampler locations are colorcoded into Area Groups consisting of adjacent NTS 

Operational Areas. The fi gures show a horizontal line 

labeled "CL" or "10% of CL." 

The annual concentration averages of tritium in air 

were decreasing during the years 1982 to 1992 and 

continued to decrease more gradually from then to 

the present time. Sampling at Schooner (in Area 20) 

was not begun until 1998 when solar photo-voltaic 

electricity was available for remote areas of the NTS. 

The decrease in tritium air concentrations is a result 

of: 1) the cessation of testing in 1992 (there have 

been no additional releases), 2) radioactive decay (the 

half-life of tritium is 12 years), and 3) its depletion 

from the soil over the years due to evaporation and 

transpiration (uptake and release of water through 

plants). Note that the scale of the tritium graph is not 

linear but logarithmic and that annual mean tritium 

concentrations by NTS area have dropped a factor of 

one thousand since the early 1980s for all areas except 

Area 20 (Schooner). 

Highest Average Concentrations of 

Man-Made Radionuclides in Air Samples on the NTS

Man-Made

Radionuclide

CL (a)

(10-15 μCi/mL)

Highest Average 

Concentration

(10-15 μCi/mL)(b)

Sampler

Location

241Am 1.9 0.048 Bunker 9-300

3

H 1,500,000 365,000 Schooner

238Pu 2.1 0.0056 Bunker 9-300

239+240Pu 2.0 0.29 Bunker 9-300

(a) Limits established by the Clean Air Act National Emission Standards for Hazardous Air Pollutants (NESHAP). 

(b) The scale of concentration units for radionuclides shown in the table have been standardized to 10-15 μCi/mL. This 

scale may differ from those reported in detailed radionuclide-specifi c data tables in the NTSER. 
 

 

11

A steady decrease in air-borne 239+240Pu over the past 

three decades has occurred at most locations. The 

gradual decrease in plutonium concentrations in air 

over time is attributed to its dispersal by wind and 

its weathering into the ground where it is bound 

to less mobile particles. Annual mean 239+240Pu 

concentrations show decreasing mean trends by areas 

and area groups over the past three decades.

239+240Pu Trends by Area Group

Average Trend Lines for Locations With at Least 14-Year Histories

0

50

100

150

200

250

1970 1980 1990 2000 2010

Year

Annual Mean (x 10 -18 μCi/mL)

A1,3

A2,4,12,16

A5 non-RWMS

A5 RWMS

A6,11

A7,9,10,15

A18,19,20

A23

A25,27

10% of CL

3

H Annual M e an Long-Te rm Tre nds

A ll Lo catio ns With at Least 7-Year H isto ries Since 1987

0.1

1

10

100

1000

10000

1980 1985 1990 1995 2000 2005

Ye ar

x 10-6 pCi/mL

A 1

A 5 RWMS

A 10,12,15

A 20

A 23,25

CL

Average Long-term Trends in Tritium at Locations

on the NTS Having at Least 7 Years of Data

Long-term Trends in Average Annual

Mean 239+240Pu for the NTS Area Groups
 

 

12 

Off site Radiological Monitoring of 

Groundwater 

There have been 828 underground nuclear tests 

conducted at the NTS. Approximately one third of 

these tests were detonated near or below the water 

table, resulting in the contamination of groundwater 

in some areas of the NTS. The comprehensive 

radiological environmental monitoring program 

on the NTS includes sampling and analysis of 

groundwater and natural springs to determine if 

groundwater contamination from past nuclear 

testing poses a current threat to public health and 

the environment. 

In 2004, BN conducted radiological monitoring of 

14 offsite wells and 2 offsite springs. The 14 wells 

include 6 private domestic and local community 

wells and 8 NNSA/NSO wells drilled for 

hydrogeologic investigations including groundwater 

fl ow modeling. All of the BN-sampled wells and 

springs are in Nevada, within 18.6 miles from the 

western and southern borders of the NTS (see map 

on page 14). 

The DRI, through the CEMP, is tasked by 

NNSA/NSO to provide independent verifi cation 

of the tritium concentrations in some of the 

offsite groundwater wells, municipal water supply 

systems, and springs used for water supplies in areas 

surrounding the NTS. Samples collected by DRI 

provide a comparison to the results obtained by BN. 

In 2004, the CEMP offsite water sampling locations 

included 17 wells, 3 water supply systems, and 4 

springs located in selected towns and communities 

within 240 miles from the NTS. Only one site, the 

Beatty Water and Sewer well, was sampled by both BN 

and CEMP.

 

Tritium is the sole radionuclide for which CEMP 

water sample analyses are run. It is also the analyte 

of primary interest for the BN sampling program. 

Tritium is the radionuclide created in the greatest 

quantities in underground nuclear tests and is widely 

believed to be the most mobile. The EPA has 

established the Maximum Concentration Limit (MCL) 

of tritium in drinking water to be 20,000 picocuries 

per liter (pCi/L) (a picocurie is one-trillionth of a Ci). 

To be able to detect the smallest possible amounts of

2004 CEMP Offsite Water Monitoring Stations
 

 

13

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2 6

6

1 4

1 1

2 7 5

2 3

2 2

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2 5

1 8

2 0 1 9

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and Training Range

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Bureau of

Land Management

1 7

Western Pahute Mesa

CAU 102

(18 CASs)

Central Pahute Mesa

CAU 101

(64 CASs)

Rainier Mesa

Shoshone Moutain

CAU 99

(66 CASs)

Yucca Flat/

Climax Mine

CAU 97

(720 CASs)

Frenchman Flat

CAU 98

(10 CASs)

5

NTSGIS:avc_Projects\NVO_EM\ETS\ASER\ASER2003\Projects\Fig3-1.mxd_Jul04

Location of Underground Nuclear Tests

} Above water table (vadose zone)

} Below water table (saturated zone)

CAU Boundary

B Predicted Regional Groundwater Flowline

2 1 0 2 4 6

Miles

2 1 0 2 4 6

Kilometers

Areas of Potential Groundwater Contamination on the NTS
 

 

14 

2004 BN Water Monitoring Locations
 

 

15

tritium in offsite water supplies, "enriched" tritium 

analyses were run on all CEMP and BN water 

samples. For the 2004 CEMP water samples, the 

MDC for tritium using this enrichment process was 

26 pCi/L. Sample-specifi c MDCs for enriched tritium 

analyses of BN water samples ranged from 17 to 

26 pCi/L. Without enrichment, the MDC for tritium 

typically ranges from 200-400 pCi/L.

BN offsite water samples are also analyzed for manmade gamma-emitting radionuclides which, if found, 

would signify contamination from nuclear testing, 

as well as for gross alpha and gross beta activity to 

determine if alpha or beta activity at any well or spring 

is increasing over time. 

Samples from two municipal water supplies, 

Boulder City and Henderson, contained tritium at 

levels barely above detection. The Boulder City water 

treatment plant sample contained 29 ± 17 pCi/L 

and the sample collected at Henderson Community 

College of Southern Nevada contained

27 ± 16 pCi/L. The uncertainty, or error associated 

with these measures (the value shown after the ±), 

indicates that the true concentrations could be as low 

as 12 or 11 pCi/L, indistinguishable from background. 

Both of these municipal water systems obtain water 

from Lake Mead. Similarly, tritium was measured 

above its MDC in only one of the BN offsite wells 

and springs; the well PM-3 sampled on May 25, 2004, 

and the concentration was just barely detectable

(20 pCi/L) in one sample and below its MDC in a 

duplicate sample collected the same day. 

All offsite BN well and spring samples contained 

detectable gross alpha and gross beta radiation, 

believed to come from natural sources. Gross alpha 

was found at levels exceeding drinking water standards 

at only one offsite monitoring well, ER-OV-02. This 

well, an NNSA/NSO well drilled specifi cally for 

hydrologic investigations, is not used for drinking 

water and is closed to the public. It produces water 

from a volcanic aquifer that may have relatively high 

quantities of natural alpha-emitting elements in the 

host rock. All gross beta concentrations in samples 

from offsite wells sampled by BN were less than the 

EPA “Level of Concern” for drinking water. 

No offsite wells contained any man-made gammaSummary of Tritium Monitoring from Offsite Wells and Springs

CEMP BN

Springs

(N=4)

Potable Wells

(N=20)

Springs

(N=2)

Potable Wells

(N=6)

Non-Potable Wells

(N=8)

Number of Sites 

Where Detected 

(above MDC) 

0 2 0 0 1

Highest Measured 

Value (pCi/L)

12 ± 22

(Adaven 

Springs)

29 ± 17

(Boulder City)

6.7 ± 15

(Spicer Ranch)

11 ± 15

(Crystal Trailer 

Park)

20 ± 12

(PM-3) 

The EPA-established maximum concentration limit (MCL) for tritium in groundwater is 20,000 pCi/L

Summary of Gross Alpha and Gross Beta Monitoring from

 Offsite Wells and Springs

Analyte

Springs

(N=2)

Potable Water 

Supply Wells

(N=6)

Non-Potable

 Water Wells

(N=8)

Gross Alpha(a) 

Number of sites where detected 2 6 8

Highest measured value (pCi/L) 6.2 ± 1.4 

(Spicer Ranch)

14.7 ± 2.7

(Beatty Water and Sewer)

51.1 ± 8.7

(ER-OV-02)

Gross Beta(b) 

Number of sites where detected 2 6 8

Highest measured value (pCi/L) 8.3 ± 1.9

(Spicer Ranch)

14.3 ± 2.9

(Roger Bright Ranch)

48.1 ± 8.1

(ER-OV-02)

(a) The EPA-established drinking water MCL for gross alpha is 15 pCi/L

(b) The EPA-established “Level of Concern” for gross beta is 50 pCi/L
 

 

16 

emitting radionuclides. The 2004 offsite water 

monitoring results, as in past years, continue to verify 

that no plume of contaminated groundwater has been 

detected beyond the NTS boundaries in public water 

supplies being monitored. 

Onsite Radiological Monitoring of 

Water

Radioactivity in onsite groundwater and surface 

waters of the NTS is monitored annually in order to 

(1) ensure that NTS drinking water is safe, 

(2) determine if permitted facilities on the NTS 

are in compliance with permit discharge limits for 

radionuclides, (3) estimate radiological dose to onsite 

wildlife using natural and man-made water sources, 

and (4) determine if groundwater is being protected 

from disposed radioactive wastes at the Area 3 and 

Area 5 RWMSs. In 2004, the onsite monitoring 

network was comprised of 10 potable water supply 

wells (9 permitted by the state), 12 monitoring wells 

(which include 3 compliance wells for the Area 5 

RWMS and 1 compliance well for the Area 23 sewage 

lagoon), 1 tritiated water containment pond system, 

and 2 sewage lagoons (see map on page 14). 

Potable Water Supply Wells 

The 2004 data continue to indicate that underground 

nuclear testing has not impacted the NTS potable 

water supply network. One water sample from each 

of three NTS supply wells had concentrations of 

tritium barely above their MDCs; none had detectable 

concentrations of man-made gamma-emitting 

radionuclides. Gross alpha and gross beta radioactivity 

were detected in most of the potable water supply 

wells at levels below drinking water limits; these are 

attributed to the presence of naturally-occurring 

radionuclides. 

Monitoring Wells and Compliance Wells

Some migration of radionuclides from the 

underground test areas to monitoring wells sampled 

annually on the NTS has probably occurred, although 

the migration distances appear to be very short. Four 

onsite monitoring wells (PM-1, U-19BH, UE-7NS, 

and WW A) had detectable concentrations of tritium 

in 2004 ranging from 23 ± 14 to 475 ± 27 pCi/L, 

all well below the MCL of 20,000 pCi/L. Each of 

the four monitoring wells is located within 0.6 miles 

of an historical underground nuclear test; all have 

consistently had detectable levels of tritium in past 

years. There were also tritium levels measured above 

their MDCs from three wells sampled to validate the 

performance of a radioactive waste disposal pit at the 

Area 5 RWMS (UE5PW-1, UE5PW-2, and UE5PW-3) 

ranging from 30 ± 12 to 37 ± 13 pCi/L. In each case, 

however, a duplicate sample collected at the same time 

from each well had measured tritium levels below its 

MDC. 

Containment Ponds 

Five constructed basins collect and hold water 

discharged from E Tunnel in Area 12, where nuclear 

testing was conducted in the past. The water is 

perched groundwater that has percolated through 

fractures in the tunnel system. Monitoring of 

the effl uent waters from E Tunnel is conducted 

to determine if radionuclides or non-radiological 

contaminants exceed the allowable contaminant levels 

regulated under a state water pollution control permit. 

Tritium concentrations in tunnel effl uent waters in 

2004 were lower than the permit limit. The E Tunnel 

containment ponds are fenced and posted with 

radiological warning signs. Given that the ponds are 

available to wildlife, game animals are sampled by BN 

to assess the potential radiological dose to humans via 

ingestion of game animals exposed to these ponds and 

to evaluate the radiological impacts to wildlife. 

Taking a water sample from an NTS non-potable 

groundwater monitoring well

(photo by Terrence Sonnenburg, May 2002)
 

 

17

Tritiated water is also pumped into lined sumps during 

studies conducted by the Underground Test Area 

Project (UGTA). To characterize the groundwater 

regime under the NTS, suitable additional wells are 

being drilled and existing wells re-completed in the 

vicinity of certain underground tests and at other 

locations on the NTS. If the tritium level exceeds 

200,000 pCi/L during these drilling operations, 

contaminated water is pumped from the wells and 

diverted to lined containment ponds, as required by 

the state. During 2004, water containing tritium was 

pumped from Wells U-3cn PS#2A, U-19ad PS#1A, 

ER-20-5 #1, and ER-20-5#3 (see map on page 14) 

into lined containment ponds. In 2004, levels of 

tritium in these ponds ranged from 113,000 pCi/L at 

ER-20-5 #3 to 38,000,000 pCi/L at ER-20-5 #1. 

Permi� ed Sewage Lagoons

Two permitted sewage lagoons (Area 6 Yucca and 

Area 23 Mercury) are sampled annually and analyzed 

for tritium using standard (un-enriched) analyses 

and by gamma spectroscopy for other radionuclides. 

As during previous years, no tritium was detected 

at concentrations above their MDCs in the lagoon 

water samples and no man-made gamma-emitting 

radionuclides were detected during 2004.

Calculating Radiation Dose to the 

Public from All Possible Pathways

Man-made radionuclides from past nuclear testing 

have not been detected in offsite groundwater in the 

past or during 2004. The only pathways, therefore, by 

which the offsite public could receive a radiation dose 

from NTS operations are the inhalation and ingestion 

pathways. 

Inhalation Pathway

The radiation dose to the general public by just the air 

transport pathway was estimated using air sampling 

results from six onsite EPA-approved “critical

receptor" sampling stations. Among these six stations, 

the Schooner air station in the far northwest corner 

of the NTS experienced the highest concentrations of 

radioactive air emissions. An individual residing at this 

station would experience a dose from air emissions of 

2.5 mrem/yr. This dose is less than the dose limit of 

10 mrem/yr specifi ed by NESHAP under the Clean 

Air Act. Dose, via the air transport pathway, at offsite 

populated locations 12-50 miles from the Schooner 

station would be even lower due to wind dispersion. 

Inhalation and Ingestion Pathway

The radiation dose to the general public from 

inhalation and ingestion of airborne radioactive 

contaminants was also estimated using the 2004 air 

sampling results and air transport models. Estimates 

of radionuclide emissions from the following sources 

were used to compute total air emissions from source 

locations on the NTS: (1) NTS facilities, (2) the 

resuspension of legacy deposits of radionuclides 

in NTS soil, (3) the transpiration and evaporation 

of tritium at sites of past nuclear tests, and (4) the 

evaporation of tritium from ponds used during 2004 

to contain tritium-contaminated groundwater. The 

table below lists the location names of NTS air 

emission sources and their 2004 emission estimates. 

The radiation dose to the general public is expressed 

as the committed effective dose equivalent (CEDE) 

to the maximally-exposed individual (MEI) and was 

computed to be 0.12 mrem/yr for a resident of Cactus 

Springs, Nevada (see map on next page). This is well 

below the dose limit of 10 mrem/yr specifi ed by 

NESHAP, and is consistent with those calculated for 

past years. 

Estimated 2004 Annual NTS Air Emissions

Source Radionuclide Quantity (Ci)

Area 23 Building 650

Area 12 E Tunnel Ponds

Well U-3cn PS#2

Well U-19ad PS#1A

Well ER-20-5 #1

Well ER-20-5 #3

Area 3 RWMS

Area 5 RWMS

Area 10 Sedan

Area 20 Schooner

3

H

3

H

3

H

3

H

3

H

3

H

3

H

3

H

3

H

0.000042 

12

0.52

18

4.5

0.020

83

4.9

200

240

Total for all 3

H Sources 3H 562.94

Total for Grouped NTS Areas 241Am 0.047

Total for Grouped NTS Areas 239+240Pu 0.29

Monitoring Results for E Tunnel Effl uent Waters 

Pertaining to Water Pollution Control Permit 

Analyte

Concentration 

Limit Set by 

Permit

(pCi/L) 

Average 

Measured 

Concentration 

(pCi/L)

Tritium 1,000,000 710,000

Gross Alpha 35.1 13.4

Gross Beta 101 72
 

 

18 

*

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*

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(

Nevada Test and Training Range

Inyo County

Esmeralda

County

Lincoln County

Nye County

Clark County

San Bernardino County

Nevada Test Site

Las Vegas

Henderson

Approximate

Location of

Maximally

Exposed

Individual

Hiko

Alamo

Rachel

Beatty

Tonopah

Crystal

Pahrump

Goldfield

Lida Junction

Stateline

Springdale

Ash Meadows

Tolicha Peak

U.S. Ecology

Clark Station

Penoyer Farms

Scotty's Junction

Furnace Creek

Medlin's Ranch

Cactus Springs

Indian Springs

Prison Complex

Mt. Charleston

Amargosa Valley

American

Cement

Amargosa Center

Sarcobatus Flat

Stone Cabin Ranch

Death Valley Junction

Twin Springs Ranch

Corn Creek Station

!(127

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10 5 0 10 20 30

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10 5 0 10 20 30

Kilometers

NTSGIS:avc_Projects\NVO_EM\ETS\ASER\NTSER04\Projects\80km.mxd_Jun05

Calculated CEDE

(mrem/yr)

0.0501 - 0.1000

0.1001 - 0.2000

0.2001 - 0.3000

0.3001 - 0.5000

0.5001 - 0.7500

0.7501 - 1.0000

* Potential Emission Source

1.0001 - 2.6128

0.0000 - 0.0500

2004 Calculated Radiation Dose from Air Emissions to the Public Within 50 Miles of the NTS
 

 

19

All Possible Pathways 

When the maximum doses from all pathways 

(inhalation and ingestion) are added together, the 

resultant total radiation dose to the MEI attributable 

to NTS operations during 2004 was 0.51 mrem/yr. 

This dose is so small it cannot be distinguished from 

the dose from background radiation (it is ~0.15 

percent of the total dose from naturally-occurring 

sources, see pie chart on the following page). It is well 

below the dose limit of 100 mrem/yr established by 

DOE Order 5400.5 Radiation Protection of the Public and 

the Environment for radiation exposure to the public 

from all pathways combined. 

DOE Order 5400.5 requires also that a collective 

population dose be estimated annually. The product 

of exposure multiplied by the size of the exposed 

population is known as the collective population dose. 

The collective population dose to all persons within 

50 miles of the emission sources on the NTS was 

estimated to be 0.47 person-rem/yr. 

Ingestion Pathway Through Game 

Animals

Each year, game animals from different contaminated 

NTS sites are trapped and analyzed for their 

radionuclide content. They are used to construct 

worst-case scenarios for dose to hunters who might 

consume these animals if the animals moved off 

the NTS and were then hunted. NTS game animals 

include pronghorn antelope, mule deer, chukar, 

Gambel’s quail, mourning doves, cottontail rabbits, 

and jackrabbits. The MEI who is a hunter is assumed 

to eat 20 doves, 20 quail, 20 chukar, 20 jackrabbits, and

1 pronghorn antelope in a year. It is also assumed that 

the dose from each animal consumed is the average 

calculated dose for that species which was sampled 

from the NTS location where the highest levels of 

radionuclides in that species’ muscle tissues were 

found. The resultant dose to a hypothetical hunter, 

given all of these worst-case assumptions, is 

0.39 mrem/yr. This dose is less than the dose from 

cosmic radiation received by an individual while on a 

one hour plane ride at 39,000 feet. 

Estimated Radiation Dose to the General Public from the NTS in 2004

Pathway

Dose to the Maximally 

Exposed Individual 

(mrem/yr) 

Estimated Collective

Population Dose 

(person-rem/yr)

Air 0.12 0.47(a)

Water 0 0

Wildlife 0.39 U(b)

All Pathways 0.51 0.47(c)

(a) Sum of radiation doses from all emission sources at each populated location within 50 miles of emission sources 

multiplied by the population at each location, and then summed over all locations.

(b) Unable to make this estimate due to a lack of data on the number of game animals harvested near the NTS by 

hunt ers in 2004. 

(c) The dose contribution from wildlife is not included. It is likely to be negligible when averaged over the entire

 population within a 50 mile radius.

Gambel’s quail (Callipepla gambelli)

(photographer and date unknown)

Pronghorn antelope (Antilocapra americana) in 

Frenchman Flat (photo by Derek Hall, May 2004)
 

 

20 

are conducted, produced more VOCs than all other 

permitted NTS facilities. Total air emissions of lead, 

also a criteria pollutant, from the NTS in 2004 was 

10.4 pounds. The quantity of HAPS released in 2004 

was 0.41 tons. No emission limits for any criteria air 

pollutants of HAPS were exceeded. In May 2004, 

the state of Nevada conducted an inspection of the 

following facilities regulated by the NTS air quality 

permit: the Area 1 Aggregate Plant, Area 1 Batch 

Plant, and the NPTEC. The state found no permit 

violations. 

Asbestos is the only non-radiological HAP of 

regulatory concern on the NTS. Building renovation 

or demolition projects may release asbestos. No large 

asbestos abatement projects were conducted on the 

Non-Radiological Onsite Air Emissions

There were no discharges of non-radiological 

hazardous materials to offsite areas in 2004. 

Therefore, only onsite non-radiological environmental 

monitoring of NTS operations was conducted. Air 

quality was monitored on the NTS throughout the year 

as required by state of Nevada permits for operations 

that release criteria air pollutants, hazardous air 

pollutants (HAPs), or toxic and hazardous chemicals. 

Common sources of air emissions on the NTS include 

particulates from construction, aggregate production, 

surface disturbances, fugitive dust from driving on 

unpaved roads, fuel-burning equipment, open burning, 

fuel storage facilities, and chemical release tests 

conducted at the NPTEC on Frenchman Flat playa in 

Area 5. The NTS has been issued a Class II air permit 

by the state of Nevada. Class II permits are issued to 

facilities which emit small quantities of air pollutants 

within a year (less than 100 tons of each criteria air 

pollutant, or 10 tons of any one HAP, or 25 tons of 

any combination of HAPs). 

An estimated 6.91 tons of criteria air pollutants 

were released on the NTS in 2004. They included 

particulate matter equal to or less than 10 microns in 

diameter (PM10), carbon monoxide (CO), nitrous 

oxides (NOX), sulfur dioxide (SO2

), and volatile 

organic compounds (VOCs). The majority of the 

emissions (4.60 tons) were VOCs. The NPTEC 

facility, where controlled spills of hazardous materials 

Comparison of Radiation Dose to the MEI and the Natural Radiation Background

Total Emissions of Criteria Air Pollutants

0

5

10

15

20

25

1994 1996 1998 2000 2002 2004 2006

Year

Tons

PM10

CO

NOx

SO2

VOC
 

 

21

NTS or at NTS support facilities in Las Vegas during 

2004. All materials containing regulated asbestos 

(asbestos that is friable and therefore potentially 

breathable) that were removed from NTS facilities 

were disposed of in the Mercury landfi ll. The 

quantities removed did not exceed EPA’s notifi cation 

threshold of 260 linear feet or 160 square feet. The 

Mercury landfi ll documented receipt of 15 tons of 

such material in 2004. 

 

Five tests, consisting of 25 releases of hazardous 

chemicals in all, were conducted at the Area 5 NPTEC 

and the new Area 25 Test Cell C NPTEC facility in 

2004. In accordance with the requirements of the 

NTS air quality operating permit for the NPTEC, an 

annual report of the types and amounts of chemicals 

released and the test plans and fi nal analysis reports 

for each chemical release were submitted to the state. 

Based on the low level of risk each test posed to the 

environment and biota, no test-specifi c ecological 

monitoring was performed. 

Non-Radiological Onsite Discharges 

into Water

There are no liquid discharges to navigable waters, 

offsite surface water drainage systems, or publicly 

owned treatment works resulting from operations on 

the NTS. Therefore, no Clean Water Act National 

Pollution Discharge Elimination System (NPDES) 

permits are required for NTS operations. 

In 2004, industrial discharges on the NTS were limited 

to two operating sewage lagoon systems: Area 6 

Yucca Lake and Area 23 Mercury systems. Under 

the conditions of state of Nevada operating permits, 

liquid discharges to these sewage lagoons are tested 

quarterly for biochemical oxygen demand, pH, and 

total suspended solids. 

Sewage lagoon pond waters are sampled annually 

for a suite of toxic chemicals. Quarterly and annual 

analyses of sewage infl uent and of pond waters, 

respectively, showed that all water measurements were 

within permit limits during 2004. The majority of 

samples had concentrations of toxic chemicals below 

detectable levels; the few toxic chemicals which were 

detectable were found at levels less than 0.1 percent of 

their permit limits. 

Non-Radiological Onsite Drinking 

Water Quality 

NNSA/NSO operates a network of nine permitted 

wells that comprise three permitted public water 

systems on the NTS which supply the potable water 

needs of NTS workers and visitors. In addition, 

three private water systems are maintained but 

are not regulated under state permit. For work 

locations at the NTS that are not part of a public 

water system, NNSA/NSO hauls potable water for 

use in decontamination and sanitation. Year 2004 

monitoring results indicated that water samples from 

the three public water systems and from the potable 

water hauling trucks met the National Primary and 

Secondary Drinking Water Standards. Samples 

from two of the water systems slightly exceeded a 

Secondary Standard for pH. No monitoring of the 

private water systems was conducted.

Area 23 Mercury Sewage Lagoon

(photo by Coby Moke, August 2005)

Non-Proliferation Test and Evaluation Complex in Area 5

(photo courtesy of NNSA/NSO)
 

 

22 

Non-Radiological Emissions into 

Air and Discharges into Water at the 

North Las Vegas Facility

Like the NTS, the North Las Vegas Facility (NLVF) 

is regulated for the emission of criteria pollutants and 

HAPs. Air quality operating permits are maintained 

for a variety of equipment, including boilers, emergency generators, and a paint spray booth. There are 

no monitoring requirements associated with these 

permits. The Clark County Health District requires 

submittal of an annual emissions inventory. The estimated quantities of criteria air pollutants and HAPs 

emitted at the NLVF in 2004 are minimal, ranging 

from 0.0009 tons for HAPS to 0.679 tons for NOX. 

Water discharges at the NLVF are regulated by a 

permit issued by the City of North Las Vegas (CNLV) 

for sewer discharges and by three temporary

state-issued NPDES discharge permits for 

groundwater discharges into the CNLV storm water 

drainage system during a groundwater characterization 

and dewatering project. Self-monitoring and reporting 

of the levels of non-radiological contaminants in 

sewage and industrial outfalls is conducted. All 

contaminant concentrations were below permit limits 

in water samples from NLVF outfalls and sludge and 

liquid samples from the NLVF sand/oil interceptor 

during 2004. Because the groundwater discharges 

are "clean" (i.e., not wastewater or discharges from an 

industrial process), no water parameters are required to 

be monitored. Sediment controls are required only if 

needed; no need for sediment controls was ascertained 

in 2004. Unauthorized discharges of tritiated water 

which occurred at the NLVF in 2004 are discussed 

below. 

Accidental or Unplanned 

Environmental Releases or 

Occurrences

Only one reportable environmental occurrence 

took place on the NTS during 2004. This involved 

the release of used motor oil onto soil. About 

75 gallons of oil leaked from a 650-gallon oil holding 

tank mounted on a lubrication truck. The direct, 

contributing, and root causes of the occurrence 

were determined. The oil release was controlled, 

contaminated soils were excavated to meet state 

clean up levels, and corrective actions were taken to 

prevent reoccurrence. No signifi cant impact to the 

environment, biota, or the public occurred as a result

of this release. 

One other environmental occurrence in 2004 was at 

the NLVF. Parts of Building A-1 were contaminated 

with tritium by a previous contractor in 1995. In 2004, 

during a pre-inspection and safety walkthrough, it was 

observed that a 5-gallon bucket of water was located 

near a fl oor drain and under the drainpipe of the airhandling unit in Room 4520 of Building A-1. The 

bucket was being used to catch condensate from the 

air handler. Upon investigation, it was learned that, on 

at least three occasions, tritiated water from the bucket 

had been emptied into the fl oor drain, constituting 

an unauthorized discharge to the CNLV sewer 

system. Water samples from the bucket indicated 

a tritium concentration of 23,000 ± 4,000 pCi/L. 

NNSA/NSO reported the unauthorized discharge 

to CNLV. Several actions required by CNLV were 

taken to prevent future discharges and document that 

the tritium concentrations at the sewage outfall for 

the NLVF were not detectable following each of the 

discharge incidents.

Overall Compliance with 

Environmental Laws, Regulations, 

and Policies

The 2004 NTSER lists and discusses the many 

applicable environmental drivers which govern the 

protection of the public and the environment during 

the conduct of NTS missions. The compliance status 

with these federal laws, state laws, regulations, and 

policies are reported in the NTSER in detail (available 

electronically at <http://www.osti.gov/bridge>). 

For this summary document, the major categories of 

these drivers are listed below. Within each category, the 

number of compliance measures monitored and compliance 

actions taken is presented along with the percentage 

of those measures or actions which met compliance 

limits or requirements. For example, under Air 

Quality, the tons of criteria air pollutants emitted on the 

NTS is just one compliance measure which is monitored 

to determine if emission quantities are within permit 

limits. An example of a compliance action under Air 

Quality is prepare annual report of calculated emissions to 

state of Nevada, which must be submitted by a specifi ed 

date. If both the tons of criteria air pollutants were all 

within permit limits, and the annual emissions report 

was prepared and submitted to the state on time, then 

the percent compliance would be 100 percent. Where 

compliance for a category is not 100 percent, the noncompliance incidents are noted. The reader is directed 

to Chapter 2, Compliance Summary, of the NTSER 

for the listing of all compliance measures and actions 

quantifi ed in the table on the next page.
 

 

23

Other Signifi cant 2004 

Environmental Accomplishments 

Environmental Restoration 

The cleanup of sites contaminated by past 

DOE operations on and off the NTS and 

the hydrogeological investigations supporting 

characterization of underground nuclear 

contamination areas are the most signifi cant 

environmental work performed by NNSA/NSO 

each year. The DOE, DoD, and the State of Nevada 

Division of Environmental Protection identify a work 

scope and milestone schedule for the cleanup and safe 

closure of the contaminated above-ground sites and 

for the fi eld investigations and model development 

necessary to characterize the underground sites. 

A total of 56 contaminated above-ground sites 

were closed safely in 2004. Extensive progress 

was made towards the development of hydrologic 

models describing groundwater fl ow and possible 

radionuclide transport from the primary underground 

sites into the groundwater underlying public lands 

outside the boundaries of the NTS. This involved 

well development, aquifer testing, groundwater 

characterization sampling, and the completion of 

several technical data documentation packages and 

modeling approach/strategy documents.

Pollution Prevention and Waste 

Minimization 

Decommissioned NTS buildings destined for 

disassembly and disposal were donated or sold for 

reuse. This waste minimization effort diverted 

approximately 31 tons of waste from the NTS 

landfi lls. The Material Exchange Program reused 

2.2 tons of non-hazardous chemicals, equipment, and 

supplies. The BN Payroll Department converted to a 

paperless, electronic time keeping system. This new 

process eliminated the need for paper timecards and 

reduced the amount of paper waste by about 2.2 tons. 

Percent of Environmental Measures/Actions Found in Compliance in 2004

Category

Number of Compliance

Measures/Actions Percent in Compliance

Air Quality 18 94

One incidence of excessive fugitive dust

Water Quality and Protection 26 96

pH (a Secondary Standard for water

quality) was exceeded in samples from 

two NTS public water systems 

Radiation Dose Protection 12 100

Radioactive and Non-Radioactive Waste 

Management and Environmental Restoration 

16 100

Hazardous Materials Control and Management 11 100

Pollution Prevention and Waste Minimization 100

Historic Preservation and Cultural Resource 

Protection

12 100

Conservation and Protection of Biota and Wildlife Habitat13 92 

16 accidental bird deaths attributable to 

NTS activities (e.g., roadkill), involving 8 

species protected as migratory birds 
 

 

24 

Other signifi cant waste reduction efforts continued in 

2004, such as selling scrap ferrous metal to a vendor 

for recycling (826 tons) and offsite recycling of mixed 

pager and cardboard (571 tons). Overall, reductions 

of 126 tons of hazardous wastes and 1,581 tons of 

solid wastes were realized in 2004. 

Historical Preservation/Cultural Resources 

Protection 

Eight years ago, the Consolidated Group of Tribal 

Representatives (CGTO), in conjunction with ongoing archaeological research, identifi ed a place of 

signifi cance to them on the NTS called Wunjiakuda. 

Before American Indian activities were disrupted 

by the Euro-American culture, Western Shoshone 

and Southern Paiute would gather at Wunjiakuda 

annually at pine-nut harvesting time. A small group of 

people lived at this location year round. The CGTO 

requested the opportunity to spend time there. In 

the late summer of 2004, an ethnographic study was 

conducted at Wunjiakuda with elders and cultural 

specialists from the Western Shoshone, Southern 

Paiute, and Owens Valley Paiute-Shoshone to record 

their knowledge about Wunjiakuda and the meaning 

of this place to them. This project, which was several 

years in the making, will result in the dissemination of 

information important to the Indian people.

Ecological Monitoring

A total of 22.3 acres of tortoise habitat were 

disturbed in 2004; no threatened desert tortoises were 

accidentally injured or killed, however, nor were any 

captured or displaced from project sites. 

A West Nile Virus Sampling Program on the NTS was 

started in 2004 with guidance from the Clark County 

Health District. BN biologists conducted 10 trapping 

sessions at eight sites on the NTS. A total of 56 

mosquitoes of two different species were collected. 

None of the mosquitoes tested positive for the West 

Nile virus. 

Three maternity roost sites of the Townsend’s bigeared bat (Corynorhinus townsendii pallescens) and two of 

the fringed myotis (Myotis thysanodes) were found on 

the NTS in 2004. Both species are designated high 

risk for imperilment by the Nevada and Western Bat 

Working Groups. NTS bat roost data were presented 

at the North American Symposium on Bat Research in 

Salt Lake City in October 2004. 

Wastes Reduced Through

 Pollution Prevention Activities

Calendar 

Year

Radioactive 

Waste 

Reduced

 (yd3) 

Hazardous 

Waste 

Reduced 

(tons)

Solid Waste 

Reduced

 (tons)

2004 0 126.3 1,581.2

2003 52.0 228.0 1,731.6 

2002 82.2 194.9 994.6 

2001 103.5 135.8 878.9 

Note: Units presented in NTSER are cubic meters 

and metric tons

Desert tortoise (Gopherus agassizii), protected as a 

threatened species by the Endangered Species Act 

(photo by Paul Greger, Jackass Flats, June 1994)

Anasazi San Juan Red potsherd from a bowl 

~ 1,000 years old, Rainier Mesa

(photo by Robert Jones, September 2004)
For More Information, contact:

U.S. Department of Energy

National Nuclear Security Administration

Nevada Site Office

Office of Public Affairs

P.O. Box 98518

Las Vegas, NV 89193-8515