Many of the nation's largest banks have ignored Treasury Department requests that they pay back $14 million in government checks bearing forged endorsements that they have erroneously cashed since 1970, according to Treasury documents.

More than $8 million of the amount was requested by Treasury more than a year ago, the documents show. Bank of America, Citibank and Chase Manhattan Bank are among the leading banks that are offenders, according to the documents.

The banks owe the money because they cashed the checks when they were legally responsible for checking the identities of the endorsers.

No interest is charged by Treasury on the past-due sums.

Treasury sources cited the department's failure to collect the money as an example of alleged mismanagement of the Treasury bureau that traces double-payments on government checks.

"The whole operation is so sloppy that they have no idea what claims they have and how much money has been lost," a former employe of the department said.

"We'll send two to three requests out to banks before we get an answer," a current employe said. "Right now," he said, "nothing is done if the banks ignore our requests for payment."

The Washington Post reported this month that Treasury makes double payments on more than 100,000 government checks a year, generally because the recipients claim they never received their checks and request a new one, then cash both the original check and the replacement check.

Included in those double payments are cases in which Treasury issues a replacement check after the original check was cashed by a forger. Under the law, banks are liable if an endorser's signature turns out to be forged.

Wolf Haber, Treasury's assistant general counsel, acknowledged that the department has not followed up sufficiently on requests to banks for payment.

"The vast majority of banks don't respond (to Treasury requests for payment)," Haber said.

He said Treasury considered deducting the past-due sums from Treasury accounts held at the banks that owe the money. "We got such a storm of protect (from the banks), we withdrew it (the proposal)," he said. But the idea is still under study, a Treasury official said.

Haber acknowledged that those same banks would downgrade credit ratings or sue if their customers were late on loan or credit-card payments.

He said Treasury could ask the Justice Department to sue banks that owe past-due sums, but Justice does not want to take on cases that involve less that $400. Most of the forged checks are Social Security or welfare benefit checks that are less than $400.

An internal Treasury memo lists only three such referrals since 1977. The cases were settled out of court or are still pending.

A Chase spokesman said, "This is money frequently owed to us by other banks (that took the forged checks). . . . We're making efforts to collect it."

Haber said banks that take the forged checks from other banks are also liable, although they can collect the money from the original banks.

Raymond Ferrari, vice president for California operations of the Bank of America, said neither Treasury nor his bank has been very concerned about the problem.

"There's been no pressure from Treasury," he said. "We don't allow our customers to get out so far if they owe us money," he said. Ferrari said he plans to require that the banks respond to Treasury requests for payment within 30 days.

Other major banks had no immediate comment.

The Treasury documents show bank of America has the largest past-due balance, $263,000. This figure does not include sums requested prior to 1978, since such breakdowns have not been compiled by Treasury.More than $109,000 of the amount owed the government by Bank of America was requested more than 120 days ago.

Also among the 20 banks owing the largest sums are Manufacturers Hanover Trust Co. ($232,000 with $119,000 due over 120 days). Chemical bank of New York ($156,000, with $72,000 past-due for 120 days), Chase ($130,000, with $58,000 overdue more than 120 days), and Citibank ($81,000, with $23,000 due more than 120 days).

In some cases, a Treasury employe said, banks ignore requests for payment over a period of years, then claim the cases are too old.

"There's an unwillingness on Treasury's part to enforce its authority," he said.

Michael D. Serlin, Treasury's assistant commissioner for disbursement and claims, said some banks demand more documentation -- such as death certificates when the names of dead recipients were forged -- before they will refund money.

Serlin said Treasury is still considering docking banks that owe money through Treasury's accounts with them and is studying ways to charge them interest on the past-due amounts.