When the bid for a Northern Virginia sewage project was opened in in summer of 1977, J.A. LaPorte, Inc., an Arlington contractor, probably thought it had won the lucrative contract. No one else had bothered to bid for the work.

To LaPorte's suprise, Stafford County officials later rejected the bid and gave the contract to a local firm that hadn't offered a proposal. When a county auditor questioned that, Stafford County supervisors directed the health department to declare the project an emergency in order to bypass the state's competitive bidding laws.

Those dealings are now coming under scrutiny of a Virginia State Police investigation, ordered to quell the continuing controversy in the largely rural county, located midway between Washington and Fredericksburg.

The 1977 incident was not the first time the county has acted in a way that has benefited Cook Brothers, Inc. a Stafford firm that has gotten the lion's share of the millions of dollars in water and sewer projects the county has awarded during the last four years.

The state police have been asked to determine whether any criminal laws may have been violated in the contract awards.

The Board of Supervisors asked for the investigation after stories appeared in local newspapers detailing allegations of questionable procedures and possible irregularities in the awarding of the contract.

The investigators are expected to look into allegations that cost increases in contracts were approved without getting necessary change orders, that the costs of projects multiplied sharply after contracts were awarded, and that rules governing competitive bidding might not have been followed.

In 1977, Cook Brothers, for example, was awarded a contract for a courthouse sewer pumping station. The original contract for about $75,000, but after Cook received the contract the county added work -- without seeking new bids -- that more than tripled the cost to nearly $400,000.

Board of Supervisor Chairman Alvin Y. Bandy said yesterday that the board wants a thorough investigation. "What we want to do is clear the air," Bandy said, "and get out whatever needs to come out."

Bandy said the county has been pleased with Cook Brothers' work and was unaware of any problems until the news articles were published.

"Cook has always been a reputable contractor," Bandy said. "We've never heard anything but good about him."

Larry Cook, the president of Cook Brothers, said yesterday his company has received no special treatment, but declined further comment. "I don't have anything to say at all at this point in time," Cook said.

LaMar Dunn, executive vice-president of Russel and Axon, a Florida-based consulting firm the county has employed for work on the projects, said he is confident the consulting company has acted properly. "We haven't done anything wrong," Dunn said. "We've been accused of several things we didn't do."

The board, in calling for the investigation, is in the unusual position of seeking a probe that will look into its own procedures. The supervisors have awarded more than $6 million in contracts to Cook Brothers during the last four years. The board has relied on the consulting company for advice and supervision of the many utility projects.

When Stafford chief prosecutor Daniel Chichester asked for the probe at the board's request, he disqualified himself immediately because of a possible conflict of interest. His assistant is the son of the Stafford County administrator, N.C. Sharp.

Supervisor Bandy, noting that the county population has grown to more than 40,000 said urban growth has been costly for Stafford. "I tell you the truth," he said, "it would be a lot less hectic if [growth] would just go away."