II. Background

BART is a rapid transit district of the State of California, existing under Sections 28500 et seq. of the Public Utilities Code (Ch. 1056, Stats. 1957). One of BART's responsibilities is the construction and operation of a rapid transit system in the counties of Alameda, Contra Costa, San Francisco, and San Mateo. The Commission has safety oversight jurisdiction over BART pursuant to Pub. Util. Code § 29047, which requires (in relevant part):

"The district shall be subject to regulations of the Public Utilities Commission relating to safety appliances and procedures, and the commission shall inspect all work done pursuant to this part and may make such further additions or changes necessary for the purpose of safety to employees and the general public."

As initially filed, the application before us requested authority to modify the existing method for train separation and control under GO 127, approve all tests for the new systems (collectively, Phase Two) and authority to commence revenue train service utilizing the Advanced Automatic Train Control System for train separation and motion control (Phase Three). As a result of the Settlement Agreement presented, approval is sought at this time only for Phase Two, the development and testing of the system. While some of this testing will occur during revenue service, it will be done in a limited area, during limited periods with operators specially trained for the new system. The request to operate full revenue service with the new Advanced Automatic Train Control System will require a separate application.