"By developing a comprehensive, risk-based plan for the chemical sector we expect to close remaining security gaps in this vitally important area," said Robert Stephan, DHS acting undersecretary for information analysis and infrastructure protection, to the Senate Homeland Security and Governmental Affairs Committee June 15.

The American Chemistry Council estimates its members have spent more than $2 billion since the 2001 terrorist attacks on physical improvements and other security steps. The council also developed a program including vulnerability assessments and stepped-up training and emergency response. Stephan says the voluntary moves have helped, but don’t cover plants accounting for 20% of the industry’s highest-risk capacity. He says there are 3,400 chemical plants where an attack could affect more than 1,000 people. Of those, 272 are in the top tier of risk.

Committee Chairman Susan Collins (R-Maine) wants more detail from the administration but says its "acknowledgment that current laws are inadequate is a positive first step." She plans to draft a chemical security bill. Stephan said DHS would work with Congress on legislation.

Earlier attempts to come up with chemical security bills failed. After 9/11, the Environmental Protection Agency looked at using Clean Air Act authority to set chemical security mandates, but decided that would lead to "protracted litigation," says Thomas P. Dunne, an EPA deputy assistant administrator. Stephan says support for new rules "is not a change in Bush policy."