Two years ago this month, after a decade of controversy, President Carter signed landmark legislation to control the ravages of stripmining from Appalachia to the Great Plains.Now it seems there will be another decade of struggle before the law weathers agonizing challenges in the courts, in Congress and in the coalfields -- if it survives at all.

The latest attack comes from the Senate Energy Committee, which has passed amendments allowing the states to ignore Interior Department regulations if they follow the intent of the law. It also would delay applying strict controls on federally owned coal lands.

The amendments, which have strong support from Majority Leader Robert F. Byrd (D WVA) and 17 coal state governors, are likely to reach the floor soon after Congress comes back next month from recess.

House Interior Committee Chairman Morris Udall (D Ariz.), father of the stripmine law, opposes the bill drafted by Sens. Mark Hatfield (R Ore.) and Wendell Ford (D Ky.). Interior Secretary Cecil D. Andrus, calling the antiregulations provision "totally unacceptable . . . a lousy amendment," says he will recommend a veto. But he won't oppose the delaying of federal enforcement on Interior's own coal lands until state programs are in force.

The battle comes at a time when Congress and the administration are promoting ever grander plans for coal -- transformation into synthetic fuels, conversion of oil fired utilities, coal slurry pipelines. Industry contends the law will inhibit coal production -- already hampered by labor problems and strict air quality rules.

In southwest Virginia, a U.S. district court barred enforcement of the law and federal inspectors were chased off the steep mountain slopes, a domain of ruggedly independent small operators. The decision recently was overturned on appeal, but the fight may reach the Supreme Court.

Indiana and Illinois have also challenged the law in federal courts.

In West Virginia, where legislators are considering joining a suit filed by coal companies, environmentalists say the state is ignoring federal requirements to monitor groundwater contamination.

Kentucky has exempted 50 mines in connection with private construction projects. While contractors say it is too costly to obtain a permit to remove coal under a construction site, nearby residents have complained of extensive damage to their homes from uncontrolled blasting.

And, whicle the law strictly limits mining on "prime farmland," Illinois, following a looser definition of the term, has allowed 20 mines to expand their operations over thousands of acres in agricultural areas.

Such individual interpretations -- acts of rebellion, environmetalists contend -- prompted the National Wildlife Federation, the Council of Southern Mountains and other conservation groups to file suit last month accusing the Interior Department of not adequately enforcing the stripmining law.

Although the law requires inspections of every mine -- there are more than 6,000 -- every six months. Interior inspected fewer than half of the surface mines and fewer than 10 percent of the undergraound mines during the six months before November 1978. Interior officials say they are doing better now.

Meanwhile several states, 105 coal companies, the National Coal Association and the American Mining Congress have filed a massive suit in U.S. district court here claiming the regulations are too tough. In connection with that suit, Judge Thomas Flannery recently granted the states a delay until March 3, 1980, to submit their regulations to Interior. Interior has until June 3, 1980, to decide whether the programs are adequate and whether to turn enforcement over to the states a deadline which Congress may extend.

Environmental groups intervened in the industry suit, contending that the regulations are actually too weak and were in fact diluted after improper intervention by the White House Council of Economic Advisers an industry ally in this case.

Environmentalists want Flannery to require greater citizen participation in state plans and to force Interior to open to the public its meetings with state officials.

Warren Gardner, a Peabody Coal Co. attorney, asked Flannery to reduce the "mountain of paperwork" requied by "a bureaucracy gone mad."

The challenge to the stripmine law, both in Congress and in the courts, is mainly a matter of economics -- who should pay for the pollution cleanup and land reclamation. But it is being argued in the more popular context of states' rights.

Coal states, with notable exceptions such as Pennsylvania, traditionally have been lenient in regulating the industry. Supporters are arguing that regulation should be left to the states.

Unless the Senate Energy Committee amendments pass, the nation is "faced with the prospect of an interminable stalemate or, worse, with the imposition of a burdensome federal program on each state." Byrd told the senate recently.

"The states have been unable to exercise the discretion due them under the act," he said. "The act has been interpreted by the Dpartment of Interior as requiring the states to duplicate every jot and tittle of the federal regulations."

On the other side, Ed Grandis of the Environmental Policy Institute says the amendments "would completely undo the progress that has been made since the stripmine bill passed in August 1977. Interior would have no legal authority to challenge state plans because it would no longer have regulations to use as the interpretation of the act."