The Owens are plaintiffs in one of several ongoing lawsuits against Halliburton over the perchlorate and radioactive material found in the soil and water around Osage Road. Their attorney, Todd Ommen from the New York City-based law firm Weitz & Luxenberg, said he could not comment on the litigation because settlement negotiations with Halliburton are ongoing. -

Low levels of radioactivity also have been found in the soil on the Osage Road site from a contract Halliburton had in the 1980s to attempt to clean metal racks that held fuel rods from a nuclear power plant in Nebraska. The state Department of Environmental Quality says the contamination is confined to the site and not a danger to residents in the surrounding area.

Perchlorate is a type of salt used in some of rocket fuels. The substance is not harmful in small quantities, but has been known to cause some health problems including hypothyroidism in larger doses over longer periods of time. Hypothyroidism is caused when the thyroid gland does not produce enough thyroid hormone. Symptoms of the condition include fatigue, shortness of breath and poor memory and concentration.

In 2011, Halliburton disclosed that it had found ammonium perchlorate in residential water wells around the closed plant in north Duncan, where the company had carried out Cold War-era defense contract work to clean fuel from spent missile casings. Ashes from the burned rocket fuel waste was stored in an evaporation pond on the site that was unlined until the late 1980s, records show.

Correspondence between Halliburton and the Oklahoma State Department of Health shows that Halliburton knew about the perchlorate at the Osage Road site as early as 1988. Emails between Halliburton and Oklahoma Department of Environmental Quality officials also show that although Halliburton was required by an agreement with the department to monitor the groundwater at Osage Road and give regular reports to the state, there was no testing and no reports were submitted between 2005 and 2009.

Emails between Department of Environmental Quality employees indicate that Halliburton was aware of the need for perchlorate testing in August 2008 — nearly three years before Halliburton disclosed the perchlorate contamination to area residents. The emails were submitted as exhibits in one of the lawsuits against Halliburton.

“They have been having groundwater problems with nitrates, but that might actually be perchlorates because they burned a lot of rocket fuel in the past,” Ray Roberts, Environmental Programs Manager for DEQ, wrote in an email. “Marc Spenser, Halliburton’s environmental guy, thinks they need to go back and reassess things because perchlorates apparently weren’t tested for.”

In a letter to the state Health Department dated Aug. 9, 1988, that has been filed as evidence as in one of the ongoing lawsuits against Halliburton, the company’s attorneys wrote that well water tests at the Osage Road plant from the area around burn pits and a holding lagoon found 2.5 parts per million of perchlorate ion —that’s 2,500 parts per billion, or more than 166 times the current EPA health advisory level of 15 parts per billion. The water and ashes from burned rocket fuel in the holding lagoon — an unlined earthen pit — had been allowed to filter through the surrounding rock and soil since 1962, according to the letter.