The federal Department of Health and Human Services is trying to recruit employes of St. Elizabeths Hospital for the mentally ill to help open and assist temporarily in operating a new shelter for the homeless in Anacostia Park.

The federal government and the D.C. Coalition for the Homeless have announced plans to open the 600-bed shelter in Southeast Washington to house men who currently stay at a crumbling downtown shelter operated by the Community for Creative Non-Violence.

The plan has been strongly criticized by Mayor Marion Barry and by CCNV leader Mitch Snyder, who has asked a federal judge to stop the government from closing the shelter his group runs at 425 Second Street NW.

Government lawyers are expected to file today with U.S. District Judge Charles R. Richey a detailed plan on shelter operations. According to a memo Tuesday by St. Elizabeths' superintendent, William G. Prescott, hospital employes are needed for up to 30 days to do mental health screening and to help operate the shelter by checking people in, maintaining order and answering phones. He said overtime will be paid "to those who are eligible to receive it."

Prescott said in the memo that supervisors should not allow anyone to volunteer if their participation "might reduce the clinical care and support required" for patients at St. Elizabeths. "Quality care for those on our rolls remains our first priority," Prescott said.

St. Elizabeths, which cares for District mental patients, currently is operated by the federal government but is scheduled to be transferred to the D.C. government by October 1987.

Prescott's memo said the Anacostia shelter will open by the end of October. However, Elisabeth Huguenin, president of the Coalition for the Homeless, said late yesterday a precise date has not been set.

Government lawyers said last week that the CCNV shelter would not be closed until at least seven days after the opening of the Anacostia shelter and a smaller shelter for women that the coalition is setting up in the Shaw area.

James F. Hunter, assistant deputy undersecretary of HHS, said renovation work on the Anacostia shelter is more than 90 percent complete. He said the coalition has hired its key staff and is "well on track" to opening its shelters soon.

As part of a plan filed last month in federal court, the government said it would supply personnel and buses for 30 days to help launch the shelter, which will occupy a vacant Navy Department building near the South Capitol Street Bridge.

The coalition has received $3.7 million from HHS to operate the Anacostia shelter until April 30 and also to establish and renovate long-term shelters for both men and women elsewhere in the city.

In August, Richey said the government could close the downtown shelter but only after moving its residents and devising a plan "to eliminate homelessness in the nation's capital." The government and the CCNV are challenging parts of that ruling before the U.S. Court of Appeals.