RICHMOND, Dec. 5--(AP)--Wilbur C. Hall, chairman of the State Conservation and Development Commission, said today he had been advised by telephone that the Federal authorities were making some modifications relative to evictions in the Shenandoah National Park area.

Mr. Hall said the State, in making evictions was carrying out instructions from the Federal authorities which would have to be followed before the park lands are transferred.

Sheriff J. Mason Smith said today that he had not received orders concerning the eviction of Robert H. Via or Mrs. Carrie A. Walton, both of Albemarle county, from the Shenandoah National Park area, while eviction proceedings against 19 families in three other counties were continued.

The case of Via, who contended that the State had no right to condemn his land for the park, was dismissed by the Supreme Court recently.

According to reports the State Conservation Commission has prepared eviction orders for both of these Albemarle property owners.

Threats of trouble were voiced by mountaineers of the Blue Ridge country today as the law prepared to evict thirteen families who have resolutely opposed all efforts to force them from the Shenandoah National Park, the Associated Press reported.

Officers of the law in four counties, where eviction writs against twenty families and nine business operators recently were served apparently, however, expected no unusual trouble.

The writs against the twenty families were issued at the insistence of the National Park service that the area be cleared by counsel for the Virginia Conservation Commission before the land is turned over to the United State government.

They were returnable in County courts today. the National park service said at Washington that thirteen of the twenty had stuck it out to the deadline.

"We ain't going," said one woman who would not be quoted by name. "We ain't been paid for our land. They'll get themselves killed."

With eviction writs for the 21 Shenandoah Park families returnable today by the sheriffs of four counties, W.C. Armstrong, counsel for the State Conservation and Development commission, said he had not received a report as to how many of the families had been removed, an Associated Press dispatch from Front Royal stated.

Mr. Armstrong said, however, that he had received appeals for aid from several of the families who said they were out of funds. He referred these appeals to Chairman Wilbur C. Hall of the Conservation Commission and Mr. Hall in turn referred the requests over to the National Park Service in Washington.

Operators of the business establishments in the park who were working under a permit containing a thirty-day notice clause, have until Dec. 21 to retire from the work.

Luther Kite, who is among those the State sought to evict, contends his residence is outside the boundaries surveyed for the park and he will be given a hearing in the Greene County circuit court Friday.

When the remaining residents of the area are gone Secretary Ickes says Uncle Sam is ready to take over, a dispatch from Washington revealed.

Title to the Blue Ridge Mountain Park area will be transferred to the United States by Virginia as soon as the mountaineers leave.

Thirteen families were said to be left today, which was the deadline for all to depart under an eviction order. Some who preceded this group took advantage of the government's offer of new homes under a subsistence loan repayment plan; others provided fo r themselves outside the park area.

The plight of families evicted from the park who, as "squatters" did not receive condemnation payments, has been turned over to the National Park Service at Washington, Mr. Hall said here yesterday at Richmond.