Wells Show Raised Radioactivity Level

Elevated levels of radioactivity have been detected in three private wells near Rockwell International’s Santa Susana Field Laboratory west of Chatsworth, according to data that seem to contradict statements by Rockwell officials.

There is no indication that the low radioactivity poses a danger or that it came from the nuclear research lab, instead of occurring naturally in the rocks and soil.

But the findings appear to conflict with statements by Rockwell’s Rocketdyne division about testing of wells near its 2,668-acre complex southeast of Simi Valley.

Responding to reports last week of pollution at the site, Rocketdyne said testing of off-site wells since 1985 “has not shown any radioactive or chemical contamination.”

But the firm’s test data show that water from two wells near Woolsey Canyon Road, east of the lab, exceeded state drinking water standards for alpha radiation in 1986. Rocketdyne officials said these wells are used for landscaping, not drinking water.

Water from both wells averaged more than 19 picocuries of alpha radiation per liter in 1986, above the state drinking water standard of 15 picocuries. Each well topped the threshold at least once during 1987 and 1988, but average alpha levels were below 15.

A third well north of the lab showed an alpha level just above 15 picocuries last year, but the annual average was under the limit.

A picocurie is a unit of radiologic measurement. Alpha radiation is not the penetrating type used in X-rays, but raises the risk of cancer if swallowed or inhaled.

Rocketdyne spokesman Pat Coulter said the firm stands by its earlier statement because “we do not consider natural background radiation to be contamination, and that’s what we’re finding in those off-site wells.”

Coulter said it is uncertain if ground water under the lab flows toward the Woolsey Canyon wells. The third is downhill from the lab.

But he said tests with an instrument that identifies the source of radiation showed that the radioactivity was not from the lab.

David Speed, a health physicist with the state Department of Health Services, said he thinks the radioactivity is natural because beta radiation readings would be higher if contaminants had seeped from the lab. He also said Rocketdyne’s data included alpha radiation from radon and uranium, which is not counted in the drinking water standard.

Ventura County officials said Wednesday they will test private wells for radioactivity at the request of residents. “There aren’t that many private wells out there that are used for drinking water, and the water supplied by the county and the city comes from the Sierra,” said Robert Gallagher, an official with the Environmental Health Department.

So “whatever happened at Rocketdyne probably wouldn’t have any impact on” drinking water, he said.

A report Wednesday by the Los Angeles Department of Water and Power confirmed that radiation levels in water from city wells in the San Fernando Valley were below state drinking water standards. Mayor Tom Bradley had requested the report after publication of news stories about contamination at the Rocketdyne lab.