CONSULTANT TO BE HIRED EXPERT TO FOCUS ON CHROMIUM 6 REMOVAL.

Byline: Charles F. Bostwick Staff Writer

PALMDALE - Los Angeles County will hire experts to offer advice on how to remove chromium 6 and other suspected carcinogens from drinking water supplies.

The Board of Supervisors on Tuesday ordered county Public Works officials to hire within 30 days at an unspecified cost a water purification consultant to recommend procedures for purifying water from county wells.

``While no one knows the 'safe' level of chromium 6, it is vital to the health and well-being of our residents that immediate steps be taken to remove known carcinogens from our water supply,'' said Supervisor Michael D. Antonovich, who made the motion to hire the consultant.

A county Department of Public Works report released last week said the department could not find proven treatment processes that would totally remove chromium 6 or other contaminants from county waterworks water supplies.

The report said treatment to remove chromium 6 likely would impose ``vast increases'' over existing costs. Under one process called ion exchange, the report said, constructing treatment facilities would cost $95 million and operating them an additional $4 million annually.

Made a household word through the movie ``Erin Brockovich,'' chromium 6 has been detected at low levels in wells around California, including dozens of county waterworks district wells in the Antelope Valley.

In Glendale, Burbank and the San Fernando Valley, which have their own water systems, chromium 6 was found in 30 of 80 wells. Glendale doesn't use well water, but is dumping 5,000 gallons of water a minute into the Los Angeles River from a new treatment plant because it contains chromium 6.

None of the 38 Antelope Valley wells tested last fall had chromium 6 at levels beyond state and federal drinking-water standards, but 30 of them had more chromium 6 than the ``health protective level'' suggested by the state Office of Environmental Health Hazard Assessment.

That agency's findings are now being studied by state health officials. State health officials must decide whether the state drinking-water standards should be changed, and whether specific limits should be set for chromium 6, now regulated only as part of the total chromium concentration.

Chromium is used in electroplating, tanning leather and making steel, among other industrial uses. Its main forms are trivalent chromium, or chromium 3, and hexavalent chromium, or chromium 6, are the main forms. Chromium 6 has been used for decades at U.S. Air Force Plant 42 as an undercoating for metal aircraft parts.

Chromium 6 is a proven carcinogen when inhaled, but there is dispute among scientists about whether it causes cancer when swallowed. Chromium 3 is a essential nutrient for humans.

Some of the Antelope Valley wells where chromium 6 was found are downhill from Plant 42, but others are in Littlerock and Lake Los Angeles, far from heavy industry.

No one has decided how the chromium could have got there, and one expert suspects that the county tests could have incorrectly measured chromium 6. Chromium 6 and chromium 3 could change back and forth during handling in the laboratory, researchers say.

However, a second round of testing by a private laboratory measured chromium 6 contamination at roughly the same levels as the tests last fall, a county Public Works report said.

Public Works officials asked for the help from a consultant, saying they lacked the expertise in the new and highly specialized area of chromium 6 treatment, according to Antonovich aide Kathryn Barger.

Public Works officials expect to have a consultant hired within 30 days and to finance the work without additions to their budget, she said. Recommendations could come out in six months or so, she said.