The federal judiciary asked Congress yesterday for extra money to make up for across-the-board cuts required under the Gramm-Rudman-Hollings antideficit act.

Without an extra $3.8 million, the judiciary said, no civil jury trials will be held in July, August and September. A spokesman for the Judicial Conference of the United States, the judiciary's policymaking arm, said the partial shutdown would mean delaying about 1,200 trials.

The budget-balancing law requires 4.3 percent cuts across the board. Agencies often come to Congress to seek extra money, but this year the new law requires legislators to offset such increases by making cuts in other areas.

In addition, the judiciary, which must cut about $40 million from its $1 billion budget, is asking for authority to reprogram funds -- in other words, to get around the requirement that cuts be evenly distributed. "If such transfers of funds are not made," Judge Charles Clark, head of the budget committee, warned, "we might have to furlough employes. . . without pay before September."

A spokesman estimated that about 1,600 of the judiciary's 18,700 employes would be furloughed five days each. The cuts range from forbidding first-class travel by judges to cutting parking fee reimbursements for jurors to closing two of the three entrances at the federal courthouse here.

Mine Over Matter . . . The inadequacies of the Interior Department's Office of Surface Mining have been a sore point up on Capitol Hill for nigh on seven years, and Rep. Sidney R. Yates (D-Ill.) was interested -- nay, eager -- to learn if the 10 extra employes Congress gave the beleaguered agency last year were helping it plow through its backlog of strip-mine violations.

Well, Director Jed Christensen allowed, the agency didn't exactly hire all the new employes, whom Congress had envisioned as "troubleshooters" who would be sent to states with high rates of strip-mine violations. Six of the positions, he told Yates at a House Appropriations subcommittee hearing last week, were never filled because of Gramm-Rudman-Hollings cuts.

Christensen conceded, however, that the agency had found the money to hire a sixth congressional liaison and a fifth external affairs expert, and to expand its public affairs staff from six to nine.

"It was just a matter of determining where the needs of the agency were, and these particular positions were needed," he said.

Christensen acknowledged that all the new hires were "schedule C" employes, holding political jobs outside the civil service system.

"Gramm-Rudman, I take it, does not apply to political hiring then, does it?" Yates asked.

"I would not say that, Mr. Chairman," Christensen replied.

"Well, I would," Yates responded.

HHS Nominees? . . . Congressional and health industry sources say the long-expected nominations of White House health expert William Roper as administrator of the Medicare and Medicaid programs, and of Assistant Secretary of Health and Human Services Dorcas Hardy as commissioner of Social Security, will be announced by the White House in the next few days -- possibly today.

Deja Vu . . . Amtrak President Graham Claytor Jr. made an annual pilgrimage to the Hill yesterday to testify before a House Appropriation transportation subcommittee about how essential federal subsidies are to the railroad's survival. This year, like last year, President Reagan has proposed to end all subsidies. This year, like last year, Amtrak's president testified that the result would be certain death.

Said Rep. Lawrence Coughlin (R-Pa.), "We could have just reprinted last year's testimony."