Metro has awarded a $3.1 million contract to a Connecticut-based firm to assume management of its troubled parking lots and garages when the transit system converts to a cashless payment system June 28.

Transit officials chose LAZ Parking Mid-Atlantic over seven other bidders for the 13-month contract after announcing that it will eliminate cash from its parking facilities and require all motorists to pay with electronic SmarTrip cards. The change came in the wake of a scandal over clerks stealing parking fees.

An investigation by Metro's auditor general found that $500,000 to $1 million had gone missing annually from parking facilities for several years and that managers ignored the problem.

The auditor said it was impossible to know exactly how much money was missing because Metro's parking facilities lacked revenue-control equipment and the agency was trusting cashiers to be honest. Transit Police Chief Polly L. Hanson said that five criminal warrants have been issued for cashiers who worked at Metro lots but that police have been unable to locate the individuals. She said the investigation is continuing.

For the past decade, Metro's parking lots and garages have been managed by Penn Parking Inc., a Maryland firm that was paid $3.1 million annually to supply cashiers and supervisors. Lisa Renshaw, president of Penn Parking, said she alerted Metro to the theft problem as far back as 1994 but was ignored.

Yesterday, Renshaw called for a congressional investigation into management at Metro, saying that an outside body should analyze the way the agency procures services and manages tax dollars.

"I have never, ever in my life experienced so much waste in government," Renshaw said, referring to the Metro managers who oversee parking. "This transit system was set up for the public as a whole, but the transit system treats it like its own fiefdom. An outside investigation team needs to go in and look at that."

Penn Parking did not bid on the contract for the new services. "I've just had too much experience with their manipulation and disregard of the public; I just don't want to have anything to do with them," Renshaw said.

She has notified 90 cashiers that they will be without jobs come June 28, when LAZ Parking assumes the operations from Penn Parking. LAZ employees will be on duty in the parking lots and garages to answer questions, make sure that SmarTrip vending machines are operating properly, monitor equipment, conduct customer surveys and alert the Transit Police of any cars left overnight. They will not handle cash.

About 75 percent of Metro passengers who park at stations already pay using a SmarTrip card, an electronic, reusable swipe card. To encourage the remaining riders to use the cards, Metro plans to install 75 vending machines in stations with parking and at major transfer stations, hold sales events at parking facilities and expand SmarTrip sales to supermarkets and shops.

One obstacle to acceptance of the SmarTrip card is that it costs $5. A tourist wanting to park in a Metro lot just once would end up paying $5 for the card and an additional $2 to $3 for parking. But tourists represent less than 1 percent of Metro's parking customers, and officials said it is more important to remove cash from the payment system.

Metro officials say they will also increase the hours during which parking fees are charged. Most Metro lots charge motorists only between 2 and 10 p.m., with those exiting earlier or later able to park free. Under the changes, motorists will be charged for parking from 9 a.m. until closing on weekdays. Parking will remain free on weekends and federal holidays.

Metro is the single largest provider of parking in the region.