An internal audit has concluded that NASA committed to an excessive and unnecessary cleanup of its portion of the Santa Susana Field Laboratory and a less expensive and invasive plan should be considered.

The audit, released recently by NASA's Office of Inspector General, estimated that cleaning up the agency's portion of the property would cost $200 million.

"NASA's estimate of more than $200 million to clean the site to background levels is more than two times the cost of restoring the land for residential use and more than eight times the estimated cost of restoring the site for recreational use," according to the audit.

"Moreover, we are concerned about the potential adverse effects on the surrounding community and on natural and archeological resources at the site should NASA press forward with clean up to background levels."

The standard of cleanup to background level was spelled out in a state law, SB 990, that was passed in 2007, but it also needed acceptance agreements from the three agencies involved in the property – Boeing, NASA and the Department of Energy. A background standard means the site must be cleaned to levels found before manufacturing took place on the property.

Joining the DOE, NASA made an agreement with California's Department of Toxic Substances Control in 2010 to meet the background standard clean-up of its 450-acre portion of the 2,850-acre former rocket testing site in the hills between Simi Valley and Chatsworth.

The Boeing Co., meanwhile, filed a federal lawsuit challenging SB 990's validity and a judge ruled in their favor. The state of California has appealed that decision and oral arguments are expected soon.

While radioactive contamination was recently confirmed on the DOE's portion, the toxic chemical found on the NASA site is trichloroethyene or TCE, a nonflammable, colorless liquid used to clean rocket engines. It has been identified as a carcinogen.

But the audit questioned whether NASA's agreement is the best use of what they called "limited environmental remediation funds."

Last year, NASA proposed what they called three less-stringent clean-up scenarios. The alternatives included cleaning up the property to standards defined as suitable for residential, industrial or recreational use. Recreational is considered the least stringent of the three, defined as involving 58,000 cubic yards of soil, for $25 million.

Some newer community activists have called for the residential clean-up, saying it would have less impact on air quality and would be less invasive on plants and wildlife and the Burro Flats Painted Caves, which contain pictographs created by Native Americans.

But longtime activists who started the clean up movement more than 20 years ago and who call the newer voices "astroturf" or artificial grassroots efforts planted by the Boeing Co, said the audit was yet another way for NASA to justify a cheap clean-up.

"This is NASA trying to back out of the binding cleanup agreement it signed," said Dan Hirsch, president of the watchdog group Committee to Bridge the Gap.

"People living near Santa Susana, beware. Your government gave its word and then tries to break it, and it is your health that ends up at risk."

The NASA audit was released just as DTSC, the regulating agency overseeing clean-up at the Santa Susana Lab, has come under scrutiny by the nonprofit group Consumer Watchdog. After a six month investigation, the group said in a report the substances control agency was not enforcing California's pollution laws. Santa Susana was among several listed as an example of weak regulation.

"The DTSC's bureaucratic culture is timid and risk adverse and its officials hide behind a weak and fractured system of environmental regulation and enforcement," according to authors of the Consumer Watchdog report. "DTSC suffers from a bias toward industry encouraged by a revolving door between regulation, lobbyists and lawyers."

State Senate Majority Leader Ellen Corbett, D-San Leandro, one of four California lawmakers who called for an investigation into the DTSC, said in a letter to DTSC director Deborah Raphael that the agency is "failing to adequately do its job to protect Californians from dangerous and poisonous substances."

Corbett is expected to meet with the agency on Monday.

The substance control agency meanwhile said the report shows a number of mischaracterizations and inaccuracies.

"But it does contain some valid issues which the department has been aware of and has already begun to address," according to a statement.

Allegations that DTSC was not doing its job are unfounded, the statement said.

"Our actions regarding the cleanup of the SSFL site is a prime example of where we have firmly held companies accountable," according to the statement. "In fact DTSC believes that its efforts pertaining to the cleanup of SSFL, its dealings with Boeing as well as the other SSFL responsible parties (NASA and DOE), the number and caliber of DTSC staff that have been assigned, and its efforts to carry out and enforce SB 990 and other stringent state law standards demonstrates DTSC's commitment to ensuring that SSFL is cleaned up to stringent and safe standards."

Still, auditors in the report callon NASA to pursue opportunities to reduce the cost of cleanup, such as negotiating with the DTSC to change the 2017 deadline and to wait for a result of Boeing's challenge to SB 990.

The Santa Susana Field Lab was developed in the late 1940s for rocket-engine tests and nuclear energy research by private-sector and government scientists from Rocketdyne, the Department of Energy and NASA, among others. Those activities resulted in a partial meltdown at one of the nuclear facilities in 1959 on the DOE property, and chemical and radioactive contamination elsewhere on the land, which has been blamed for higher rates of cancer in neighborhoods near the property.

The majority of the site is now owned by the Boeing Co., which bought Rocketdyne in 1996 and later closed down the facilities.

NASA is also looking to dispose of its portion of the site.

In 2010, NASA filed a declaration with the federal General Services Administration, saying it no longer had any use for its 450-acre parcel at the rocket-test site facility.

The declaration clears the way for the GSA to offer the land to other federal agencies for use. If none is interested, the parcel will be declared surplus and offered to state, city, school districts and nonprofit organizations. If there still are no takers, the land could be sold to the highest bidder, which some community groups fear could open it up to development such as a gaming casino.

UPDATE: An earlier version of this story said newer community activists called for recreational clean-up, when in fact, they call for residential standards.

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