Since 1956, the plant now owned by ATI Wah Chang, formerly known as Teledyne, has operated as a rare metals extraction facility. The types of metals produced there include zirconium, hafnium, tantalum and niobium.
These metals are slightly radioactive and their production generated radioactive wastes that contaminated the immediate and surrounding environment. Other wastes the plant has released into the environment include volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and heavy metals.
ATI Wah Chang was listed as a Superfund site in 1983. Between 1983 and 2002, the company has completed many clean-up actions and conducted extensive environmental sampling as part of the Superfund process. This was done under the direction of the Environmental Protection Agency (EPA).
Investigation and Assessment
The Environmental Health Assessment Program (EHAP) used the environmental sampling data to assess whether or not contaminants from the site are putting the public's health in jeopardy. Read EHAP's final Public Health Assessment. This final version incorporates previously unknown data on fish caught from neighboring Second lake - dating back to 1991. The review of this data has shown the fish to be low in the 2 site-related contaminants that would accumulate in fish. The contaminants tested for were hexachlorobenzene and PCBs. These were chosen because out of all the site-related contaminants, these are known to bio-accumulate in fish tissue.
Since 1991 there has been more remediation, and Second Lake has been cleaned up even further. EHAP has concluded that eating the fish out of Second Lake now, or in the past, poses no risk to human health based on the available data.
- Public comment was accepted until November 4, 2008, and incorporated into the final version of the report.