It has been 20 years since Congress included provisions in the 1990 Clean Air Act Amendments to inform citizens of risks from factories using hazardous substances, but the data that details the potential effects of accidents at these sites is largely unavailable to the public.

In 1999, the Environmental Protection Agency began requiring plants that use a threshold amount of certain toxic or flammable substances to submit a risk management plan detailing what they are doing to prevent accidents and how they would respond if one occurred. But some lawmakers became concerned about one section of risk plans that laid out what might happen to nearby residents if something went wrong at a plant. That information – the Off-site Consequence Analysis (OCA) – could be used by terrorists or other criminals to transform a factory into a weapon, they said.

Congress stepped in, temporarily exempting the OCA information from disclosure under the Freedom of Information Act. The EPA ultimately set up a system where members of the public can view up to 10 individual plant sites’ OCA information per month at a federal reading room after showing a photo ID and filling out a sign-in sheet. Visitors can take notes but aren’t allowed to make copies.

Brian Turnbaugh, a policy analyst at advocacy group OMB Watch, said the current system doesn’t hide anything from terrorists and inconveniences citizens seeking information about their communities.

“We do not believe that disclosing this information would place a facility at risk,” Turnbaugh said. “It’s actually quite the contrary. We think that getting this information engages the public to push for safer processes.”

OMB Watch has compiled information from individual OCA reports into a database – albeit not a comprehensive one – that it uses to analyze trends and push for safer technology, Turnbaugh said. But it would prefer the EPA publish online the agency’s complete risk management plan database, including OCA information, much as the EPA already does with its Toxics Release Inventory.

“We’ve seen with the TRI (Toxics Release Inventory) how public disclosure drives pollution reduction, and that’s what we’re hoping to see,” Turnbaugh said. “EPA has acknowledged that the benefits of [disclosure] include the ability to reduce the number and severity of chemical accidents that might occur.”

Another purpose of requiring plants to submit risk management plans, aside from informing citizens of chemical risks, was to provide information for emergency responders. Local emergency personnel can easily acquire a complete copy of a plant’s risk management plan, including the OCA section, from the EPA, said Tim Gablehouse, president of an emergency responders group known as NASTTPO.

Gablehouse agreed that disclosure of OCA information would not pose a severe security risk but was unconvinced that the full database should be readily available to anyone. “In the post-9/11 world, it’s a little difficult to argue for completely anonymous online access to this information,” he said.

The EPA did not respond to requests for comment.

Overall, though, the current system for accessing OCA information is “overly burdensome,” Turnbaugh said. “We basically feel like it’s more of an inconvenience for people who need to know and have information to protect themselves and their families.”

About the data:

What: Off-site Consequence Analysis (OCA) detailing the potential effects of accidents at facilities using hazardous substances

Where: Environmental Protection Agency

Availability: Plant OCA information is available only in federal reading rooms. Other portions of a plant’s risk management plan is available by filing a FOIA request.

Update - August 12

In an email response to the Center, a spokesman for the Environmental Protection Agency said risk management plan data has not been available online since the Sept. 11, 2001, terror attacks. “Representatives of law enforcement and intelligence agencies expressed concern that releasing the OCA (Off-site Consequence Analysis) portions of risk management plans via the Internet would enable individuals anywhere in the world to conduct anonymous electronic searches for the purpose of causing an intentional industrial chemical release,” the spokesman said.

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The Data Mine is a joint project of the Center for Public Integrity and the Sunlight Foundation.