A Montgomery County government workers' association wants the state to investigate county contract records that the County Council ordered sealed last year following an investigation of alleged improprieties in contract awards.

The Montgomery Country Government Employees Organization, which says it represents about 1,800 of the conty's 5,000 employees, has tried unsuccessfully to get the council to make the records public. The group says the council's refusal to do so amounts to a cover-up of records involving more than $3 billion in contracts.

Council members said last November's order that the records must remain sealed for 10 years was meant to protect innocent person's reputations from "gossip, rumor and innuendo" that the records allegedly contain.

The council's investigation resulted in several findings and recommendations. A concurrent investigation by the conty state's attorney's office produced no prosecutions.

The newly elected council has decided to form a committee of at least three of its members to review the records sealed by the odd council "to ascertain the validity" of keeping then sealed. But the council has not acted on to a request from the employes organization that it join them in asking Maryland Attorney General Stephen H. Sachs to investigate.

Sachs, who has been asked directly by the organization to investigate the records, said he has not yet determined whether "there is any appropriate role for this office to play."

Charges of improprieties in contract procedures were raised in 1974 by A. B. Waller, a county employe who later lost his job and said he was fired because he raised the issue.

The move to have a counsil committee review the records was initiated June 26 by council member Rose Crenca, who said she felt "a moral obligation to know what I have sealed."

Council member Esther Gelman declared at that meeting that reviewing the records could lead to a "smalltime McCarthy era."

Joseph A. Yablonski, an attorney representing a group of citizens including Waller, called the council's "refusal to order the immediate release" of records "a fraud."

"The surest way to avoid making a decision is to appoint a committee to study the problem, "Yablonski said.