Federal regulators have decided to let off the hook nearly 100 savings and loan associations that are holding more than $700 million worth of delinquent loans to Equity Programs Investment Corp. (EPIC), the failed Falls Church tax shelter organizer.

Although no payments have been made on the loans for months, the Federal Home Loan Bank Board recently prepared a directive saying the loans do not have to be reported as delinquent by federally insured thrifts, according to officials familiar with negotiations between regulators and EPIC investors. The decision means that S&Ls saddled with EPIC mortgage loans or mortgage-backed securities will not, for the time being, have to write them off or set aside cash reserves to protect against losses, as is usually required for bad debts.

A bank board official said the agency decided the EPIC loans do not have to be considered bad debts because progress is being made on a plan to bail out bankrupt EPIC real estate partnerships and resume payments to lenders. The decision was made after consultations with a group of major EPIC lenders working on the plan.

But the decision also has fueled criticism that the bank board once again is using irregular accounting techniques to prevent ailing thrifts from collapsing. By not counting the unpaid EPIC loans as bad debts, S&Ls will be able to show higher profits and greater net worth than if they had to write off part of the loans. The board previously has adopted other accounting techniques that artificially improved the financial health of many S&Ls. The agency also has allowed many savings and loans that are technically insolvent to continue operating because there is not enough money in the Federal Savings and Loan Insurance Corp. to pay off depositors.

Payment on the loans was halted in August when EPIC collapsed and more than 350 EPIC partnerships filed for bankruptcy. Threatened with millions of dollars of losses, the savings and loans holding EPIC paper have, with the support of bank board officials, sought to keep their names secret. A U.S. bankruptcy judge in Alexandria, Martin V. B. Bostetter, in October issued an extraordinary order sealing the names of EPIC's creditors, saying he feared there will be runs on the S&Ls if depositors find out who they are.

EPIC creditors include at least a dozen federally insured S&Ls in the District, Virginia and Maryland and several of the largest S&Ls in the country, according to sources involved with EPIC, court papers and a list of creditors obtained by The Washington Post.

The largest potential losers from EPIC's collapse include the Federal National Mortgage Association, with more than $100 million in EPIC loans, and the giant Philadelphia thrift PSFS, which holds about $215 million in EPIC paper. PSFS operates Meritor Savings Bank branches in the Washington area.

Other major local EPIC creditors include Dominion Federal Savings & Loan in Northern Virginia, Washington Federal Savings & Loan and Baltimore Federal Financial. All told, 94 federally insured S&Ls hold $703 million of EPIC mortgage debt, according to figures compiled in May by federal regulators examining EPIC's parent, Community Savings & Loan of Bethesda, which has been taken over by the state of Maryland.

The federal examiners also found that 18 banks insured by the Federal Deposit Insurance Corp. hold about $250 million of EPIC paper. An FDIC spokesman said the agency has set no special policy with respect to those loans.

Investors held a total of $1.24 billion in EPIC mortgages as of March 31, according to the examiners, though EPIC's mortgage debts are now thought to exceed $1.4 billion. Banks, savings associations and other investors loaned money to EPIC partnerships to buy single-family houses. Often, several of these loans were packaged together and sold as securities to investors.

Under rules recently adopted by the bank board, thrifts are required to set aside specific reserves to protect against losses from potential bad loans, such as the EPIC mortgages. As a result of the bank board's EPIC decision, however, thrifts would not be required by federal regulators to establish such reserves for the EPIC loans, banking officials said.

One congressional banking specialist, who asked not to be named, said the bank board's action comes as little surprise given its general nervousness about having to bail out troubled thrifts. He said regulators were essentially employing an "accounting gimmick" designed to avoid forcing the thrifts to write down part of the loan and thus depress their net worth below federally accepted levels.

A bank board official, who also asked not to be named, said a recent agreement by three mortgage insurance companies that backed most of the EPIC loans to put up $43.3 million in an escrow account to pay potential claims convinced regulators that the loans need not be written off yet. Once a bailout plan is approved, those funds would cover interest payments on the mortgages for August, September and October.

A memo issued to field examiners Dec. 20 in the name of Francis M. Passarelli, acting director of the Office of Examinations and Supervision, outlined the agency's action. The memo stresses that the use of escrowed funds to bring the loans current has been accepted only in the EPIC case "and therefore does not constitute policy."

Despite the decision, some EPIC creditors already have taken write-offs for their EPIC investment. PSFS Terms Investment 'Nonperforming'

Philadelphia's PSFS said it already has classified the EPIC investments as "nonperforming." A spokesman said the company took $21 million off its third-quarter earnings and allocated the money for future losses on the investment.

PSFS said it took the write-down based on its analysis of the property underlying the loans, but other thrifts said they had not made such allowances because they believe the value of the property covered by their mortgages, as well as insurance, should cover any shortfall. PSFS not only took a write-off on its EPIC investments, but also made public its exposure to EPIC because it is a stockholder-owned institution regulated by the Securities and Exchange Commission. Federal securities laws and regulations generally require companies to disclose all important financial information to their stockholders.

Several institutions that are not covered by SEC disclosure rules have refused to discuss their EPIC investments. Others confirmed that they hold EPIC paper and said they don't expect to suffer more than minimal losses. "In no way will we suffer the full loss," said Dewitt T. Hartwell, chairman of Columbia First Federal Savings & Loan in the District, which recently disclosed that it owns about $5 million worth of EPIC mortgage-backed securities. Columbia First Started Reserve Fund

Soon after the EPIC problems became known, Columbia First said it established a reserve fund for uncollected interest on its investments, which are supposed to pay the bank about $45,000 a month in interest.

Columbia First disclosed its EPIC exposure in a prospectus issued this fall when it sold stock to the public. The association has no current plans to change its accounting, despite the bank board's ruling, Hartwell said.

Allan R. Plumley, president of Continental Federal Savings Bank in Fairfax, said his thrift owns about 70 EPIC loans worth about $5 million. He said the bank has stopped reporting income on the EPIC loans, but has not established any loan-loss reserves.

"That decision has not been made because we think that we have good product," said Plumley. "We think we can recover it all. We did underwrite all these loans. And don't forget, we also have private mortgage insurance."

The Virginia First Savings Bank of Petersburg, with $14.7 million of EPIC holdings, has set up an $850,000 reserve fund for the interest that it was supposed to accrue since EPIC stopped making payments on the loans, according to Charles A. Patton, executive vice president. Patton added that Virginia First has not set up a reserve for possible loss of any principal.

In contrast, Edward Cunningham, executive vice president of Life Federal Savings & Loan in Norfolk, said his thrift is continuing to accrue interest on its EPIC loans, which total less than $2 million. "Accruing interest" means that Life Federal is continuing to record on its books the interest that is supposed to be paid on the EPIC loans, even though the interest is not being collected. Cunningham said the thrift expects to recover all of its investment because its loans date from 1979 and 1980, and thus much of their principal has been paid off.

F. Ripley Bowman, president of Potomac Savings Bank in Silver Spring, said that federal examiners already have told his thrift that it need not classify its $1 million of EPIC loans as problem assets. "We asked them if they would discount any of our net worth because of EPIC, and they said no," he added.

Executives of several other savings institutions that have been identified in various court papers as EPIC creditors refused to say how much EPIC exposure they have. These include Dominion Federal Savings and Loan of McLean, Atlantic Federal Savings & Loan in Baltimore and Maximum Savings Association of Chevy Chase.

William L. Walde, Dominion Federal's chairman, confirmed that the thrift owned some EPIC paper, although he refused to say how much. He also said Dominion Federal serviced EPIC mortgages for other investors.

Dominion Federal was involved in at least four separate kinds of financial transactions with EPIC or its parent, Community Savings & Loan:

*Dominion owns some EPIC mortgages or mortgage-backed securities. Sources familiar with EPIC say Dominion purchased millions of dollars worth of EPIC paper, but Walde inisists those figures are not correct. He refused to say how much Dominion is owed by EPIC or its affiliates.

*Dominion also made loans to EPIC partnerships secured not by property, but by promissory notes signed by investors in the partnerships, according to documents filed in U.S. Bankruptcy Court in Alexandria.

*Dominion has a $1.1 million interest in a Community loan to buy and renovate the Lincoln Building in downtown Washington. According to bank board documents, the borrower "has no equity in the project and leases are insufficient to meet debt service." Walde said, however, that the borrower is current on interest payments and that he expects Dominion's full share of the loan will be paid off.

*Dominion purchased $8.6 million of Community's share of a construction loan for an apartment complex in Michigan. The thrift's interest subsequently has been paid off, Walde said.

A list of institutions that held EPIC mortgage debt also include, among others, Washington Federal Savings and Loan and Home Federal Savings and Loan, both in the District, although their executives refused to discuss any EPIC holdings.