Land-reform workers in El Salvador have charged that the reform program, strongly supported by the Reagan administration as a key to future Salvadoran democracy and stability, is near collapse because of military-backed terror and murder, illegal peasant evictions and a slow, "frequently hostile" bureaucracy.

In a December report requested by Salvadoran President Jose Napoleon Duarte, the executive board of the Union Comunal Salvadorena, the country's largest peasant organization and an indirect recipient of U.S. aid for educational and advisory assistance to the program, said that "the failure of the agrarian reform process is an immediate and imminent danger."

Asked Friday about the report, the State Department dismissed the UCS statistics as "not as a rule definitive or reliable" and characterized the land-reform program as "a remarkable success story."

The administration must certify to Congress this week that the Salvadoran government is "making continued progress in implementing" promised reforms, including land reform, or risk a cutoff of the $25 million in U.S. military aid and $40 million in economic assistance budgeted this year for El Salvador.

The congressional restrictions, which also require certification that El Salvador is making progress toward stemming human rights abuses and promoting a political rather than military solution to the country's civil war, were mandated last month in response to concern over administration backing for the Salvadoran leadership.

But background conversations with administration officials about questions raised both by the UCS report and a recently completed internal Agency for International Development audit of a $10 million U.S. aid project to assist the land reform, as well as an extensive response prepared for The Washington Post by U.S. Ambassador to El Salvador Deane R. Hinton, reflected a deep concern about the problems they pose for certification.

The audit, dated Dec. 17, 1981, notes "progress" in the project, but it cites serious difficulties in monitoring the distribution of U.S. funds. It notes that AID receives information on the reform only through government meetings and written reports, with no field work of its own because of security problems.

While the congressional restrictions on aid contain no provision for rejecting administration certification, the House subcommittee on inter-American affairs, chaired by Rep. Michael Barnes (D-Md.), has scheduled hearings to begin Feb. 3 on El Salvador.

Although Barnes said in an interview last week that he fully expects the certification to be made, he said the hearings were intended to allow the administration to justify it and to allow critics of U.S. and Salvadoran government policies to air their views. The UCS document is expected to be discussed in the hearings.

Land reform was decreed in early 1980, about six months after a group of reform-minded young military officers staged a successful coup against the last in a long line of rightist generals.

The land-reform program is divided into two operative parts, designed to benefit nearly one-fifth of El Salvador's 5.5 million people. It calls for government expropriation, with compensation, of more than 300 large agricultural estates to be turned over to peasant cooperatives, and the granting of ownership titles for small plots to as many as 125,000 sharecroppers and tenant farmers.

Land redistribution, along with other political and economic reforms promised by the new government and supported by the United States, was considered vital to satisfy the aspirations of El Salvador's majority peasant class and to counter appeals to them by the left, which argued that revolution was the only way to alter permanently the status quo. The reforms have been bitterly opposed by the conservative Salvadoran business community, and the large landowners for whom the rightist military historically ruled the country.

The Reagan administration has continued its predecessor's support for the reforms, while stepping up military aid to help the government in its year-old civil war with leftist guerrillas. It does not dispute that there are serious problems with the land-reform program, many of which it blames on bureaucratic inefficiency and the size of the task.

However, while it acknowledges a lack of control over elements of the military by civilians who now share power with the Army, it contends that the government is gradually bringing these elements to heel. In the administration's view, the bulk of the problems are caused by the guerrillas, who it charges are sabotaging the reforms and killing more civilians than the military.

While economic aid is necessary to promote the reforms, the administration argues, the defeat of the guerrillas is vital if the reforms are to succeed.

Critics of U.S. policy, including a number of members of Congress, long have maintained the opposite. They charge that despite the good intentions of some in the Salvadoran government, the reforms are being thwarted by rightists in the same military that is pledged to implement them and the wealthy who want to return to the status quo. This situation, they maintain, is merely perpetuated by U.S. military aid.

A copy of the critical UCS report, which is dated Dec. 10, and covers events in 1981, was given to The Washington Post by Leonel Gomez, the former deputy director of the Salvadoran government agency charged with carrying out the land reform. Gomez, who now lives in Washington and publicly opposes U.S. policy in El Salvador, fled his country last January when agency director Rodolfo Viera, a former head of the UCS, was killed there with two American labor officials.

The State Department was given a copy of the report by the AFL-CIO-affiliated American Institute for Free Labor Development, which has worked in El Salvador since 1966, and helped found the UCS in 1968 as an association of peasant cooperatives.

According to the labor institute's deputy director, Sam Haddad, current UCS membership is about 110,000 peasants. In the past two years, the labor institute has received U.S. aid grants, this year totaling $1.5 million, which it uses to pay about 200 UCS officials and members to promote land reform and give technical assistance to its beneficiaries and to monitor implementation of the program in the countryside.

While he emphasized that the labor institute and the UCS are "still very supportive" of the land-reform concept, Haddad said "a lot of the things" in the UCS report "are true" and that the labor institute stands behind the documentation. Both the labor institute and Gomez, who requested that he be identified as having released the report to the press, expressed fear that newspaper publication of the charges in the report would place UCS officials in El Salvador in physical danger.

"I can see people down there . . . the extreme right . . . being most upset, and taking revenge, if it got out that the executive board of the UCS published this," the labor institute's assistant director, Jesse Friedman, said. The two Americans killed with Viera last January, Michael Hammer and Mark Pearlman, were employes of the institute Two Salvadoran businessmen were arrested in connection with the deaths, but one has since been released.

Gomez maintained that UCS leaders were "risking their lives" by compiling the document, but said that "I don't talk about the 'extreme right.' I talk about the Salvadoran Army."

Among its specific allegations, the report says that "at least 90 officials" of peasant organizations, many of whose cases are detailed in one of several appendices to the report, and "a large number of beneficiaries" of the land reform "have died during 1981 at the hands of the ex-landlords and their allies, who are often members of the local security forces."

It says more than 25,000 former sharecroppers or tenants have been forcibly evicted from their farms, "in the majority of cases with the assistance of members of the military forces," before they could claim the ownership documents.

Using figures that generally agree with those of AID for the same period, the report notes that only about 15,000 families eligible for individual ownership have been granted provisional titles to their land.

Since the program began in April 1980, no permanent titles have been granted to individuals. Of more than 300 peasant cooperatives formed on former large, privately owned estates, only two have received title to the land. One more title was granted after the UCS report was compiled.

"What had begun in March and April of 1980 with bright promise, and had continued to show bright promise even through the end of 1980," an 11-page summary of the document concludes, "now threatens to become a nightmare of bureaucratic red tape, evictions and killings, in which it will soon be beyond the capacity of the government or the campesino peasant leadership to prevent a complete loss of faith by our country's campesinos in the agrarian reform program.

"If and when this happens, the extreme left will have free rein throughout the countryside and all prospects for ending the violence or instituting democracy will be at an end."

Ambassador Hinton disputed a number of the figures in the UCS report, described some as "unproven," and differed in interpretation of others.

"While the embassy does not deny that implementation of the agrarian reform can be improved," he said in a written response to questions transmitted to the State Department, "it is essential to view the reform within the context of violence and social upheaval taking place in El Salvador today."

Addressing specific points in the document, Hinton said that 20,000 provisional titles have been issued to sharecroppers and tenant farmers, covering 30 percent of what he said were 67,000 potential benificiary families.

The State Department and AID, in previous documents and congressional testimony, consistently have calculated the number of potential beneficiaries as 125,000, the figure also used by UCS. The new figure of slightly more than half the original, Hinton said without elaboration, was due to "subsequent analysis based on the best available data."

Without addressing directly the delays in granting permanent titles to small-plot farmers, Hinton said "the important considerations, rather than estimates based on insufficient or dated statistics, is that the process is continuing and is doing so under conditions less than ideal."

Hinton said the titling of large cooperatives, with only three out of 326 farms completed so far, remained a "serious bottleneck and will continue to be unless major legal reforms are made of the entire registry process. The chances of this taking place in the immediate future are not likely."

Although the UCS and others have charged that the lack of titles raises the hopes, and spurs the actions, of those who hope to reverse the process, Hinton said that titling "is only one part of the agrarian reform process" and that the important thing is that the cooperatives are now in possession of the land, with or without titles.

On the question of evictions, Hinton said that in those provinces "not affected by the high levels of violence, little in the way of evictions has occurred and that generally but not always the armed forces are, within their own limited capacities, giving support to the entire agrarian-reform process including attempts to assist farmers who have been illegally evicted."

He said that killings of civilians have decreased in the past year, and that while they still occur, "the number is impossible to determine with any degree of accuracy." In general, human rights organizations monitoring the situation in El Salvador agree that, after a high level last winter and through the early spring, the number of deaths decreased through the summer. But listings by the University of Central America in San Salvador, among others, show an upswing beginning in October.

The labor institute maintains that the UCS report is accurate because of the organization's extensive field reporting. According to the AID internal audit of its assistance to land reform, "because of the political situation in El Salvador and inadequate staffing," the AID office there confined its monitoring of the project to "periodic meetings with government officials and reviews of statistical reports." Field visits to projects, it says, "were discontinued due to dangerous conditions that existed in project areas."

The audit, which covers the period from July 7, 1980, to May 31, 1981, notes that "progress was being made in achieving the objectives." It goes on, however, to raise serious questions about lack of technical assistance to cooperatives and of supervision over the spending of U.S. funds, including "about $872,000 of ineligible loan expenditures" reimbursed by AID in El Salvador.

AID officials in San Salvador said all the deficiencies pointed out in the audit had been corrected, but they declined to detail measures taken until they have been officially communicated to Washington.

Washington Post special correspondent John Dinges contributed to this article from San Salvador.