(a) Railroad tank car vulnerability assessment

(1) Assessment
The Secretary shall assess the likely methods of a deliberate terrorist attack against a railroad tank car used to transport toxic-inhalation-hazard materials, and for each method assessed, the degree to which it may be successful in causing death, injury, or serious adverse effects to human health, the environment, critical infrastructure, national security, the national economy, or public welfare.

(2) Threats
In carrying out paragraph (1), the Secretary shall consider the most current threat information as to likely methods of a successful terrorist attack on a railroad tank car transporting toxic-inhalation-hazard materials, and may consider the following:

(A) Explosive devices placed along the tracks or attached to a railroad tank car.

(B) The use of missiles, grenades, rockets, mortars, or other high-caliber weapons against a railroad tank car.

(3) Physical testing
In developing the assessment required under paragraph (1), the Secretary shall conduct physical testing of the vulnerability of railroad tank cars used to transport toxic-inhalation-hazard materials to different methods of a deliberate attack, using technical information and criteria to evaluate the structural integrity of railroad tank cars.

(4) Report
Not later than 30 days after the completion of the assessment under paragraph (1), the Secretary shall provide to the appropriate congressional committees a report, in the appropriate format, on such assessment.

(b) Railroad tank car dispersion modeling

(1) In general
The Secretary, acting through the National Infrastructure Simulation and Analysis Center, shall conduct an air dispersion modeling analysis of release scenarios of toxic-inhalation-hazard materials resulting from a terrorist attack on a loaded railroad tank car carrying such materials in urban and rural environments.

(2) Considerations
The analysis under this subsection shall take into account the following considerations:

(A) The most likely means of attack and the resulting dispersal rate.

(B) Different times of day, to account for differences in cloud coverage and other atmospheric conditions in the environment being modeled.

(C) Differences in population size and density.

(D) Historically accurate wind speeds, temperatures, and wind directions.

(E) Differences in dispersal rates or other relevant factors related to whether a railroad tank car is in motion or stationary.

(F) Emergency response procedures by local officials.

(G) Any other considerations the Secretary believes would develop an accurate, plausible dispersion model for toxic-inhalation-hazard materials released from a railroad tank car as a result of a terrorist act.

(3) Consultation
In conducting the dispersion modeling under paragraph (1), the Secretary shall consult with the Secretary of Transportation, hazardous materials experts, railroad carriers, nonprofit employee labor organizations representing railroad employees, appropriate State, local, and tribal officials, and other Federal agencies, as appropriate.

(4) Information sharing
Upon completion of the analysis required under paragraph (1), the Secretary shall share the information developed with the appropriate stakeholders, given appropriate information protection provisions as may be required by the Secretary.

(5) Report
Not later than 30 days after completion of all dispersion analyses under paragraph (1), the Secretary shall submit to the appropriate congressional committees a report detailing the Secretary's conclusions and findings in an appropriate format.