What is a Plutonium Pit?

A plutonium pit is the softball-sized bomb core that begins the chain reaction in every modern US thermonuclear weapon. Currently, there is no demonstrated need for new plutonium pits to ensure the safety or reliability of the existing US nuclear weapons stockpile. In fact, these new pits will be for entirely new nuclear weapons. This kind of production involving extremely dangerous radioactive materials puts workers and nearby communities at risk.

History of Pit Production

During the height of the Cold War, the Rocky Flats Plant in Colorado was the nation’s producer of pits , manufacturing 1,000 to 2,000 pits per year between 1952-1989. Major fires occurred at Rocky Flats in 1957 and 1969, both involving plutonium. The site was raided by the FBI and the U.S. Environmental Protection Agency in 1989 for environmental crimes and permanently closed in 1992. The Los Alamos National Lab (LANL) in New Mexico then produced 29-30 pits between 2007-2011 to end the Rocky Flats production run. The US has tried, and failed, several times to revive plutonium pit production — LANL did not produce another pit until October 2024.

In 2018, the federal government ordered the production of at least 80 pits per year by 2030, including at least 30 pits at LANL and at least 50 at the Savannah River Site (SRS) in South Carolina. In 2021, Nuclear Watch New Mexico, Savannah River Site Watch, Tri-Valley Communities Against a Radioactive Environment (CAREs), and the Gullah/Geechee Sea Island Coalition of coastal Georgia sued the National Nuclear Security Administration (NNSA) for failing to consider the full programmatic impacts of plutonium pit production across sites.

In January 2025, this lawsuit resulted in requiring the NNSA to produce a Programmatic Environmental Impact Statement (PEIS) on plutonium pit production. After scoping hearings in May of 2025, the NNSA released their draft PEIS in April of 2026, kicking off in-person hearings in Livermore, CA, Santa Fe, NM, Aiken, SC, Kansas City, MO, and Washington, DC, as well as a 90-day online public comment period.

Up-to-Date Resources

Sample Comments for the Draft Plutonium Pit Production Programmatic Environmental Impact Statement (PEIS) from NukeWatch NM

Why should you comment? This process produces valuable information, increases government accountability and transparency, and creates a legal administrative record that has led to important litigation in the past. The Trump administration is severely limiting and removing key opportunities for public comment and objection. Significantly, there is no other legally required opportunity that enables the public to comment on the “modernization” program to keep nuclear weapons forever.

BACKGROUND: The Department of Energy’s (DOE’s) semi-autonomous National Nuclear Security Administration (NNSA) is aggressively expanding the production of plutonium pits, the radioactive cores or “triggers” of nuclear weapons. The Los Alamos National Laboratory (LANL) in New Mexico has been capable of producing plutonium pits since 1996, and until 2018 production was capped at no more than 20 pits per year. NNSA now plans to produce up to 205 pits every year for the new arms race, with at least 80 pits per year made at LANL and at least 125 per year at the Savannah River Site (SRS) in South Carolina.

Grassroots activist organizations Nuclear Watch New Mexico of Santa Fe, NM; Savannah River Site Watch of Columbia, SC; the Gullah/Geechee Sea Island Coalition of coastal Georgia, and Tri-Valley CARES of Livermore, CA successfully sued the NNSA over its failure to complete a required nationwide “programmatic environmental impact statement” (PEIS) for its plan to massively expand plutonium pits production. A draft of this PEIS was released in April 2026, kicking off in-person hearings in Livermore, CA, Santa Fe, NM, Aiken, SC, Kansas City, MO, and Washington, DC, as well as a 90-day public comment period ending July 16, 2026. This provides a unique and critical opportunity for public scrutiny of and formal comment on the government’s plans to make new nuclear bombs for a new arms race!

VIEW/DOWNLOAD SAMPLE COMMENTS [WORD DOC]