Chemical Security Act of 2003

Chemical Security Act of 2003 - Directs the Administrator of the Environmental Protection Agency to promulgate regulations to: (1) designate certain combinations of chemical sources and substances of concern as high priority categories based on the severity of the threat posed by an unauthorized release from chemical sources; and (2) require each owner and operator of a high priority category chemical source to conduct an assessment of the vulnerability of the source to a terrorist attack or other unauthorized release, identify hazards that may result from such release, and prepare a prevention, preparedness, and response plan.

Sets forth: (1) certification requirements regarding assessments, and completion and review of response plans, by owners and operators of high priority chemical sources; and (2) protocols for protecting information disclosed in such certifications.

Sets forth provisions regarding: (1) certification by the Administrator of source assessment and plan compliance with requirements; (2) compliance assistance; and (3) compliance orders.

Provides that if the Secretary of Homeland Security determines that: (1) a threat of a terrorist attack exists that is beyond the scope of a submitted plan, or that plan implementation is insufficient, the Secretary shall notify each source of the elevated threat; and (2) a source has not taken appropriate action in response to the notification, the Secretary shall notify the source, the Administrator, and the Attorney General. Authorizes the Administrator or the Attorney General to then secure such relief as necessary to abate a threat.

Sets forth: (1) source record-keeping requirements; (2) entry and access rights of the Administrator; and (3) civil, criminal, and administrative penalties for violations of this Act.