The number of locations where pollution in storm water runoff is monitored at the Santa Susana Field Laboratory will be cut by nearly half after a decision by local water regulators Thursday.

The decision is a major boon for Boeing Co., the Field Laboratory's owner, which has long sought to have the stringent runoff limits, once touted by the same regulators, eased.

The Los Angeles Regional Water Quality Control Board voted unanimously to eliminate a number of monitoring sites where wastewater and storm water run off the Field Laboratory in the hills south of Simi Valley when it met Thursday at Simi Valley City Hall. Last December, the state water board directed local regulators to reconsider two pairs of monitoring sites because they were redundant.

The board surpassed the two in question and eliminated other sites because operations in those areas on the former rocket engine and nuclear test site had ceased.

Monitoring of two runoff points, one of which drains into the Dayton Canyon area and the other onto the neighboring Brandeis-Bardin property, will be temporarily suspended until 2009 at Boeing's request. The aerospace company will use the time to put ecologically friendly filtering systems in place. They will be guided by an independent expert panel that will be selected with the help of the water board and company officials.

"We appreciate the board's careful consideration of this matter," Boeing spokeswoman Blythe Jameson said. "We are very excited to bring in an outside panel of experts to help us meet our water-quality objectives and look forward to sharing this knowledge in pioneering storm water treatment technologies."

Community members and watchdogs were taken aback by the decision they say came after board members had some tough words for Boeing.

"The result of this will be more people exposed to carcinogens leaking off of this contaminated site," said Dan Hirsch, president of the nuclear watchdog group Committee to Bridge the Gap said. "It will also lead to much greater cynicism about our regulatory agencies. It's also a huge slap in the face to the community by a pollution control agency that acted more like a wholly owned subsidiary of the polluter."