U.S. Environmental Protection Agency
75 Hawthorne Street (AIR-6)
San Francisco, CA 94105-3901

LAWRENCE BERKELEY NATIONAL LABORATORY

TRITIUM ISSUES

FEDERAL CLEAN AIR ACT CONSIDERATIONS

The Clean Air Act sets National Emissions Standards for Hazardous Air Pollutants (NESHAPs) for radioactive air pollutants from facilities such as those of the U.S. Department of Energy. The NESHAP standard was issued in 1989 after a two-year public rulemaking process, which included scientific evaluation and peer review, a public comment period and analysis of public exposure from all the Department of Energy facilities. The final NESHAP standard was set in terms of a radiation dose at 10 millirem a year (a millirem is the effect of radiation exposure, often called a radiation "dose"), in accordance with a court directive to determine a level that was "safe with an ample margin of safety." In comparison, a chest x-ray emits approximately 25 millirem instantly; naturally occurring radioactivity and cosmic radiation account for 100-300 millirem a year.

The NESHAP is based on radiation science which considers children, fetuses and genetics. The standard was set low enough to assure the safety of children.

Lawrence Berkeley National Laboratory has provided NESHAP reports since 1989. Emissions produced doses less than 0.2 millirem a year, which is less than 1/50 of the 10 millirem public health standard. The doses were based on an EPA model called "CAP88." The Laboratory uses CAP88 to calculate a dose to someone who might live 24 hours a day, 365 days a year at the Lawrence Hall of Science. That person would be considered the maximally exposed individual (MEI). Data entered into the model come from the Laboratory’s stack monitors, which run continuously as required by the NESHAP. Beyond the NESHAP monitoring requirement, the Lawrence Berkeley National Laboratory uses electronic monitors to measure and record real-time computer-recorded information. When tritium was accidentally released recently, the NESHAP monitoring determined that 35 curies of tritium had been emitted. (A curie is a measurement of radioactive material. A Laboratory emission would be expressed in curies of tritium.). That resulted in a dose less than one millirem. Even combined with this accidental release, the year’s dose will be far below the EPA standard.

The Laboratory also monitors tritium in the air, water, and soil. This includes monitoring the air for tritium at the Lawrence Hall of Science. Since October, 1997, EPA has taken part of each of the monthly samples from the Lawrence Hall of Science for its own analysis. Results are expected shortly.

Is the Lawrence Berkeley National Laboratory currently emitting tritium?

EPA has twice visited the Lawrence Berkeley National Laboratory to ensure that while taking samples at the Lawrence Hall of Science, the tritium facility is operational and tritium labeling is occurring. Inspection of activity logs and stack monitoring records indicates that the facility is indeed operating and monitors are measuring tritium emissions. Sampling at the Hall of Science will reflect this.

For more information, please contact Shelly Rosenblum, U.S. EPA Air Division, (415) 744-1047.