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RadNet

History of RadNet

RadNet and its forerunners have been collecting environmental radiation data for more than 50 years. The timeline below shows how the RadNet system began and how the network has monitored radiation in the environment over the years.

Chronology

Milestone

1945-1955

Approximately 80 above ground nuclear blasts are conducted during this period by the U.S., the Soviet Union, and Great Britain.

1956

Radiation Alert Network (RAN) is set up to provide an early alert for radiation fallout. When included in Environmental Radiation Ambient Monitoring Systems (abbreviated ERAMS, now RadNet) in 1973, RAN had 68 sampling stations spread across the United States.

1956-1958

Approximately 180 above ground nuclear blasts were conducted during this period by the U.S., the Soviet Union, and Great Britain.

1958

Great Britain conducts its last above ground nuclear blast.

1959

Executive Order 10831 and Public Law 86-373 issued, providing the legal basis for additional programs that eventually led to RadNet. Monitoring of radioactive fallout and environmental radiation became a responsibility of the Department of Health, Education, and Welfare (HEW).

1960

Pasteurized Milk Network (PMN) was set up to monitor for radiation fallout in the human food chain. When brought into ERAMS (RadNet) in 1973, PMN had 63 sampling stations across the nation. Years later, the U.S. Food and Drug Administration will monitor radiation in milk as part of its food safety responsibilities.

France conducted its first three above ground nuclear blasts. These were the only blasts reported for any country this year.

1961-1962

Approximately 100 above ground nuclear blasts were conducted during this period by the U.S. and the Soviet Union.

1963

The U.S. and the Soviet Union stopped above ground nuclear blasts, partly because of the Cuban Missile Crisis and resulting Limited Test Ban Treaty that prohibited underwater, atmospheric and outer space nuclear blasts.

1964

Tritium Surveillance System (TSS) was set up to monitor precipitation and tritium concentrations in major river systems downstream of selected nuclear facilities. When incorporated into ERAMS (RadNet) in 1973, TSS consisted of 8 monitoring stations.

People's Republic of China conducted its first above ground nuclear blast. This was the only above ground blast reported for any country that year.

1965-1967

Nine above ground nuclear blasts were conducted during this period by France and the People's Republic of China.

1967

TSS expanded to include drinking water and a larger network of surface water stations. The TSS consisted of 68 drinking waster sampling stations and 39 surface water stations before being added to ERAMS (RadNet).

1968-1970

Three above ground nuclear blasts were conducted during this period by the People's Republic of China.

1970

Radiation monitoring responsibilities transferred from HEW to EPA based on Reorganization Plan No. 3.

1971-1973

Seventeen above ground nuclear blasts were conducted during this period by People's Republic of China and France.

1973

ERAMS is established by consolidation of several existing monitoring networks. ERAMS (RadNet) data begins being reported as summary data in quarterly NAREL Environmental Radiation Data (ERD Journal Reports.

1974

Seven above ground nuclear blasts were conducted during this period by France and the People's Republic of China.

France conducted its last above ground nuclear blast.

1976-1978

Six above ground nuclear blasts were conducted during this period by the People's Republic of China. ERAMS (RadNet) provided information about the weapons tests and detected environmental releases of radioactivity. See, EPA Assessment of Fallout in the United States from Atmospheric Nuclear Testing on September 26 and November 17, 1976 by The People's Republic of China (PDF).

1979

Electronic recording of ERAMS (RadNet) data began. It included individual sample analytical results in the ERAMS (RadNet) Laboratory Information Management System (LIMS).

Three Mile Island (U.S.) nuclear power plant - A cooling malfunction caused part of a reactor core to melt, resulting in a limited off-site release of radioactivity (INES Level 5).

Analysis of tritium (H-3) in milk ended.

1980

The People's Republic of China conducted its last above ground nuclear blast.

Saint-Laurent (France) nuclear power plant - A fuel rupture resulted in a minor off-site release of radioactivity (INES Level 4).

1982

Analysis of uranium (U) and iodine (I) in drinking water begun.

1985

Analysis of plutonium (Pu) in milk ended.

1986

Chernobyl (Soviet Union) nuclear power plant - A steam explosion and fire caused a major off-site release of radioactivity (INES Level 7). ERAMS (RadNet) reported increased levels of radioactivity in the environment.

1987

Analysis of carbon-14 (C-14) in milk ended.

1993

Publishing of ERD Journal Reports began on the website of the National Analytical Radiation Environmental Laboratory (NAREL), Montgomery, Alabama.

1996

Analysis of U and Pu in precipitation ended.

1999

Surface water samplings ended (to avoid duplicating state sampling programs around nuclear facilities).

Tokaimura (Japan) nuclear fuel processing facility - A criticality accident results in a minor off-site release of radioactivity (INES Level 4).

2000

Wildfires threatened the Los Alamos National Laboratory in New Mexico and scorched 200,000 acres of Hanford nuclear reservation in Washington State. ERAMS (RadNet) provided regional and national data to compare to samples taken in response to the fires.

2001

Terrorist attacks on September 11 (U.S.) - Airliners flown into the World Trade Center and Pentagon. ERAMS (RadNet) provided regional and national data to compare to samples taken in response to the attacks. Later, ERAMS (RadNet) was re-evaluated and updated to increase geographical coverage and better support national decision makers during emergencies.

2002

Individual ERAMS (RadNet) sample data became available on the EPA website.

2005

ERAMS became RadNet, a name chosen to better reflect the mission of the program.

2006

The first near-real-time RadNet air monitor was placed in service in San Diego, CA on April 20, 2006.

2011

The Fukushima Daiichi Nuclear Power Plant in Japan, damaged by a major tsunami caused by a massive earthquake, released radioactive materials into the environment. RadNet deployed portable monitors in Alaska, Hawaii and the Pacific Territories, and accelerated its sampling and analyses schedules for air filters, precipitation, drinking water, and milk. RadNet detected miniscule quantities of radionuclides associated with the Fukushima accident. After a thorough data review showed declining radiation levels in these samples, EPA returned to the routine RadNet sampling and analysis schedule for precipitation, drinking water and milk on May3, 2011. The last time that EPA detected radioactive elements associated with Fukushima was July 28, 2011 in Hawaii. 

2014

The RadNet monitoring network grows to 134 stationary monitors distributed across the entire U.S. EPA discontinues its milk sampling because it is redundant of U.S. Food and Drug Administration (FDA) programs and FDA has the responsibility for food safety, including monitoring radiation in milk.