(a) In general. The Administrator shall provide access to a computer-based indicator that shall inform any person located in any state whether an address specified by that person might be within the vulnerable zone of one or more stationary sources, according to the data reported in RMPs. The indicator also shall provide information about how to obtain further information.

(b) Methods of access. The indicator shall be available on the Internet or by request made by telephone or by mail to the Administrator to operate the indicator for an address specified by the requestor. SERCs, LEPCs, and other related state or local government agencies are authorized and encouraged to operate the indicator as well.