Naval Radiological Defense Laboratory facts for kids
The United States Naval Radiological Defense Laboratory (NRDL) was an early military laboratory. It was created to study the effects of radiation and nuclear weapons. The facility was located at the Hunter's Point Naval Shipyard in San Francisco, California.
Studying Radiation and Nuclear Weapons
The NRDL was formed in 1946. Its main job was to manage testing, cleaning, and getting rid of U.S. Navy ships. These ships had been contaminated by the Operation Crossroads nuclear tests in the Pacific Ocean.
Many ships that survived the atomic explosions were brought to Hunter's Point. Here, they were studied in detail and cleaned. Some ships were cleaned well enough to be sold for scrap metal.
The aircraft carrier USS Independence was one such ship. It was badly damaged and covered in nuclear fallout from the Operation Crossroads explosions in July 1946. The Independence was brought to the NRDL for study. After years of trying to clean the ship, the Navy eventually filled it with nuclear waste. The radioactive ship was then sunk off the coast of California near the Farallon Islands in January 1951. The ship's wreck was found resting upright under 790 meters (about 2,590 feet) of water in 2009.
The NRDL used several buildings at the Hunter's Point shipyard from 1946 to 1969. They worked with the United States Atomic Energy Commission. This group was the first version of what is now the Nuclear Regulatory Commission. The Navy did many radiation experiments on materials and animals at the lab. They even built a special machine called a cyclotron to help with these experiments. They also stored different nuclear materials there.
What the NRDL Did
Records that are now public show some of the activities at NRDL. Scientists at the NRDL:
- Managed the dumping of large amounts of contaminated sand and acid into San Francisco Bay. This happened after these materials were used to try and clean radioactive ships.
- Spread radioactive material on and off the base. They did this to practice how to clean up such materials.
- Burned radioactive fuel oil in a boiler. The smoke from this was released into the air.
- Sold ships that had become radioactive as scrap metal to a private company.
- Placed a source of cobalt-60 in San Francisco Bay for two weeks. Cobalt-60 is a nuclear material that gives off strong radiation, like X-rays. They wanted to see what would happen.
- Studied the effects of radioactive elements on people.
- Experimented with important amounts of various long-lasting radioactive poisons. These included plutonium, cesium, uranium, thorium, and radium.
- Studied and disposed of thousands of animals that had been exposed to radiation. These animals included mice, rats, dogs, goats, mules, and pigs. At one point, the lab even owned a ranch to raise animals just for radiation testing.
- Considered dumping liquid waste with small amounts of radioactive materials into San Francisco Bay. This was to study how ocean tides would spread out the radioactivity.
Environmental Impact and Cleanup Efforts
The testing and cleaning activities at NRDL caused a lot of contamination at the shipyard. The NRDL and a military radiation training school nearby dumped nuclear waste from experiments. They put the waste into steel barrels. Then, weekly barges took these barrels to dump them offshore. This dumping happened near the Greater Farallones National Marine Sanctuary. This area is a U.S. National Wildlife Refuge and an important fishing spot.
Between 1946 and 1970, it's estimated that the lab and naval station dumped about 47,000 drums of nuclear waste. This happened in the Pacific Ocean, about 30 miles west of San Francisco. This created the first and largest offshore nuclear waste dump in the United States. The U.S. Geological Survey (USGS) says these barrels contain "low-level radioactive waste." However, some historical records and experts disagree with this.
The U.S. Navy finished a Historical Radiological Assessment of the Hunter's Point Shipyard in 2004. This assessment looked at the known NRDL facilities on the property. However, declassified documents showed that many sites and buildings used by NRDL were not included in the Navy's list of potentially contaminated sites. Many of the buildings once used by NRDL had already been torn down by then.
The former shipyard site is still being cleaned up today. It has been divided into smaller areas. This allows the Navy to declare each area clean and safe for new buildings separately. New homes have been built and sold on parts of the former Hunters Point Naval Shipyard. However, some people involved in the cleanup believe the site is still heavily contaminated. They have raised concerns about how the cleanup company has handled testing and safety.
