Beginning next month, Virginia Electric and Power Company (Vepco) will replace two miles of old and damaged underground cables in Reston that are being blamed for the area's recent rash of power failures.

Vepco spokesmen said the electrical cables are worn out and ruptured by heavy road and housing construction around the Reston and Tysons Corner areas.

"An area such as Reston, which has a tremendous amount of development, is prone to this kind of damage," said Jerry Norris, Vepco Herndon-Reston district manager.

Centreville District Supervisor Martha V. Pennino said she started receiving complaints from Reston residents about the power failures three years ago.

"As time went on the outages increased and I realized I really had a problem over there," Pennino said.

"People were suffering inconvenience and hardship, so I decided to make it a political issue and bring the situation the power outages before the Board of Supervisors."

On June 25, the board authorized County Executive J. Hamilton Lambert's staff to investigate the electrical malfunctions and see what could be done to eliminate the problem.

One month later the county's Department of Consumer Affairs contacted Vepco officials, who agreed to initiate a cable replacement program.

The Virginia utility company said it would spend more than $100,000 to install 10,590 feet of new cable on 18 Reston streets, starting in mid-November at Laurel Glade Court, in the Glenvale subdivision.

Other streets slated for cable repair include Marginella Drive, Stone Wheel Drive, Petersborough Court, White Cornus Lane, Old Fields Drive and Emerald Heights and Prince Harold courts.

Roger Dittman, director of Vepco's consumer services, said the scheduled 18 streets had "experienced the most outages . . . and need the most attention."

Dittman added that the company would spend $20,242 for 2,130 feet of new underground cable on Michael Faraday Court, near the Reston Industrial Park.

Pennino said she will monitor the company's progress carefully and "make sure they do what they say they are going to do. If my staff tells me we're still getting complaints, I'll call and tell them Vepco I'm not happy."

Vepco said the outage problem occurs when powerful electrical currents surge through old and damaged cables, weakening or breaking them and causing a blackout. Some homeowners said the power failures have lasted from 15 minutes to eight hours.

Lionel Schmemann, whose house on Winterport Cluster was hit 10 times this summer with power blackouts, said he keeps extra candles handy now. Schmemann said the outages have plagued his block since 1981.

Some residents have lost more than electrical convenience since the lights started going out in Reston. Dennis Sager said his color television short-circuited immediately after a power surge last summer and he had to buy a new set.