The Interior Department, seeking to end a strip-mining controversy in Virginia, has withdrawn a series of orders accusing coal companies of environmental abuses in the state's Appalachian coalfields.

The move marked a turnabout in a battle triggered last summer when the federal agency seized control of authority to police malpractices by strip miners and other coal operators in Virginia's mountainous southwestern region. Federal officials had accused the state of failing to punish coal companies for environmental violations.

An Interior official, who asked not to be identified, said yesterday that the switch in tactics was designed to end an increasingly tangled legal conflict and improve the atmosphere for negotiations between Virginia officials and Interior's Office of Surface Mining. Federal, state and other officials noted, however, that the controversy has not yet been settled.

Interior has not withdrawn its additional surface-mining inspectors, who were sent to Virginia's coalfields as part of the federal takeover. Nor has the federal agency dropped its demand for stiffer action by Virginia to penalize coal operators for environmental abuses, officials said.

"We're still negotiating," said Mike Abbott, a spokesman for Virginia's Division of Mined Land Reclamation. Officials for coal industry and environmental organizations expressed uncertainty yesterday about what impact Interior's tactical shift may have.

Despite the federal agency's withdrawal of more than 20 complaints against coal operators, the companies appear likely to face prosecution by the state. The Office of Surface Mining has notified the state of the apparent violations, and Virginia officials are expected to take action shortly. At issue, however, is whether the state's measures will be stringent enough to meet federal demands. Abbott said the state plans to continue employing its more lenient procedures.

Efforts to curb strip-mining abuses have long caused controversy in Virginia, where the coal industry is an economic mainstay and an influential politcal factor. Government and environmental critics have repeatedly accused the state of laxness in regulating its coal mines. Virginia went to court to challenge the landmark 1977 Surface Mining Control and Reclamation Act, upheld by the Supreme Court last year.

The law is designed to prevent flooding, soil erosion, water pollution, landslides and other damage by imposing stiff environmental safeguards at mine sites and requiring coal operators to restore their land to its approximate original contours after mining is completed.

Last summer's federal takeover in Virginia was the first such action against any coal-producing state.

Environmentalists quickly criticized the federal move as illegal and expressed concern that it would likely backfire, leaving violators unpunished. They called for a switch in tactics, similar to what has now occurred. United Coal Co., one of the nation's largest privately held mining firms, obtained a court order temporarily barring U.S. officials from imposing sanctions for alleged violations. Virginia officials demanded withdrawal of the federal inspectors, contending that the state's policies had been spelled out in Virginia laws previously approved by Interior.

Yesterday, Abbott said the state is weighing two options that may help end the controversy. One would require new state legislation early next year to revise Virginia's regulatory practices. The other would entail stepped-up administrative action to allow a shift to stiffer penalties for violations.

Mark Squillace, a lawyer for the Washington-based Environmental Policy Institute, asserted yesterday that Interior's switch in tactics amounted to an admission that the federal takeover was illegal. "They basically acknowledged that they were wrong," he said. "It's what we've been saying all along." He called for further steps by state and federal officials to curb mining abuses.

An industry spokesman reiterated objections to the federal takeover. "Nothing really has been settled between OSM and the state yet," said Sandy DySart, executive director of the Virginia Mining and Reclamation Association. "Nobody is really comfortable with the situation. We're not sure what's going to happen next."