For Immediate Release
September 9, 1999

Potomac Electric Power Company (NYSE: POM) today completed participation in a nationwide Year 2000 readiness drill in what Pepco Chairman and Chief Executive Officer John Derrick called a successful tune-up for Jan. 1. "We've worked to make Y2K a non-event," Derrick said.

Pepco's participation in the drill began at 8 a.m. Wednesday and continued through the midnight rollover to the ninth day of the ninth month of 1999. Today's date was considered a pre-Y2K test date by some computer experts because some older mainframe computers used 9/9/99 to mark the end of a program or file and then would stop processing. Pepco had no problem with the 9/9/99 rollover.

The exercise was conducted in conjunction with NERC, the North American Electric Reliability Council, and with energy suppliers and utilities in the mid-Atlantic region's power pool, the PJM Interconnection Association.

Pepco went beyond NERC's drill requirements to conduct a full-scale dress rehearsal for December 31 and January 1, 2000. More than 325 employees-many of the same staff that is scheduled to beef up what would be the normal New Year's Eve workforce-was on duty at Pepco power plants, electric substations, control center, emergency command center and other key locations. The company's Y2K contingency plans were tested under scenarios simulating the loss of critical voice and data communication systems that could affect the transmission and delivery of reliable electric service.

NERC held its first nationwide drill April 9 when utilities tested their backup communication systems for the power plants. This drill was expanded to evaluate Y2K readiness and emergency procedures in power generation, distribution systems, control systems and customer service.

Pepco began its Year 2000 preparations in 1995 with development of a corporate-wide effort to identify all of the company's computer operating systems and embedded technology that possibly could be vulnerable to a Y2K computer glitch. Over the past four years, teams of Pepco employees and consultants developed and installed appropriate changes when necessary to make the systems Y2K ready. An extensive series of tests was performed to determine whether the corrective measures worked. In June, Pepco reported that it completed its Y2K readiness work on all systems critical to the generation and delivery of reliable electric power.