Nearly all the nation's 160,000 striking coal miners ignored a Taff-Hartley back-to-work court order yesterday, and the government, pinning its hopes on delicate contract negotiations, made no moves against them.

Last night, however, Attorney General Griffin B. Bell directed U.S. attorneys in the coalfields to "consider arrests of any persons threatening to interfere with coal miners returning to work" and to "be alert to any action by union officials which could have the effect of discouraging [miners] from returning to work."

Bell also reminded all union officials to "pay attention to that portion of the court order which obligates them to do everything necessary to see that miners obey their instructions to return to work."

A Justice Department aide described the action as a "selective level of enforcement not inconsistent with the government's desire not to upset the contract negotiations."

As the mines opened for the first week of work in more than three months, silence spread over the coalfields from the Rockies to the Appalachians: no confrontations, no turmoil, no coal production.

And, in Washington, there were no formal bargaining meetings, although rumors circulated from both the coal industry and the United Mine Workers that another tentative settlement - two were previously rejected - could come at any time.

Negotiators kept in contact with each other by telephone yesterday and scheduled a full-scale bargaining session for today on union demands and industry counteroffers dealing with the key contract issues of health and pension benefits and wildeat strike restrictions.

As of late yesterday, the Bituminous Coal Operators Association, the 130-company industry bargaining group, counted fewer than 100 miners who had showed up for work, or 1 for every 1,600 UMW strikers.

About 30 of them showed up at Eastern Associated Coal CO.'s Keystone No. 1 mine near Welch. W. Va., and were put to work on maintenance. Other miners showed up here and there, none in sufficient numbers to start mining coal, according to BCOA.

Some scattered picketing was reported, but no violent confrontations. "There was no one to confront with," said a government official.

Despite earlier vows by President Carter to enforce the Taft-Hartley order vigorously, the government was taking a wait-and-see approach, moving cautiously to avoid causing a rupture in the contract talks.

The Justice Department has "no plan and no desire to go dashing into court to have people held in contempt . . . so long as there is some hope of a peaceful settlement," said Mark Sheehan, a department spokesman.

Union officials will still be held accountable if they violate the order by seeking to perpetuate the strike, he said, and any "flagrant violation" will be dealt with promptly. "We simply have no desire to create a confrontation where none exists," he said.

Individual miners cannot be forced to go back to work against their will, but union officials, down to local officers, can be fined or jailed for contempt of court for doing virtually anything to perpetuate the work stoppage. In 1948, the UMW was fied $1.4 million and its then-president, John L. Lewis, was fined $20,000 for violating a Taft-Hartley order.

Many union officials last weekend were fulfilling the letter of the law and no more. Some were refusing to do even that.

Bell characterized the government's strategy as one of "concurrent movements": enforcing Taft-Hartley and encouraging bargaining.

He said he hoped the possibility of a breakup of industrywide bargaining would be sufficient to drive miners back to work before the contempt process has to be used, although both union and industry officials have scoffed at such a linkage between the two strategies.

But they have agreed that the specter of a bargaining collapse brought them scurrying back to the bargaining table late last week, fearing that company-by-company settlements would create even more chaos than now exists in coalfield labor relations.

The government, with Carter having declared an impasse in industrywide negotiations, was actively pushing individual settlements early last week.

An administration source said yesterday that at least two major coal companies, including Peadbody and Island Creek, were ready to negotiate separately "if they could find someone to bargain with."

At the same time, UMW President Arnold Miller was sending out signals he would have to consider separate talks if two or more companies indicated they could settle that way, the source said. At this point, it was apparently decided to give industrywide bargaining one more chance.

As for future Taft-Hartley compliance, government officials expressed confidence that more miners would return to work later this week and presidential press secretary Jody Powell said reports from the field were "encouraging" in terms of getting some coal moving again, although he did not elaborate.

There were reports yesterday that the coal operators agreed in the weekend negotiations to reduce proposed health-care deductibles if the union would allow production incentives, which it previously rejected as likely to impede safety. The operators also had been reported ready to reduce the proposed deductibles, which could cost miners as much as $700 a year, if the union would forgo benefit guarantees. But a bargaining source indicated both proposals may be out of date.