Despite President Carter's goal announced two years ago to double U.S. coal production by 1985, a congressional study to be released today says that growth in coal demand will continue to be slow over the next decade.

A study by the Office of Technology Assessment concluded that because of low demand for coal, the industry will likely continue to have surplus production capacity during the next decade.

"Coal is not normally the fuel of choice unless it offers a large cost advantage," OTA said in its 441-page of report, "The Direct Use of Coal."

In recent years coal production has lingered slightly above its earlier peak in 1947 at about 700 million tons.

OTA says that coal production could triple by the end of the century, but under less promising conditions may only double. Compared with 1977, when coal production stood at 689 million tons, OTA forecasts that production will total from 1.5 billion to 2.1 billion tons by the year 2000.

According to OTA the greatest increases in coal consumption will come from the West-Central and Mountain states.

Carter's 1977 goal called for 1.2 billion tons of coal use during 1985.

Energy Secretary James R. Schlesinger has repeatedly said that coal use in the United States is likely to "continue to be demand limited" during the next years, despite the Energy Department's forecasts of tight oil and natural gas supplies.

If coal is going to "stage the comeback that has been forecast" OTA says the industry will have to draw on a new generation of technology that meets environmental, mining safety, and other stiff operating requirements that have been stitched into law in recent years.

Despite advances in mining techniques and the demands of new legislation, the report finds that "large-scale coal development may still be accompanied by substantial environmental impacts."

Other major findings in the OTA report are:

The proportion of surface mining, now about 60 percent of total production, will not increase dramatically in the years ahead.

While the number of mining fatalities-there were 139 in 1977-is declining, the number of disabling injuries to miners has risen dramatically to nearly 15,000 in 1977.

Consequently, OTA finds, statistical trends in mine safety "may conceal no improvement or even a worsening of safety in deep mines."

Depending on future coal production, OTA says between 157 and 187 coal workers "are likely to be killed and between 17,400 and 20,800 injured in 1985.

The decline in miner productivity, which has dropped since 1969, "seems to have bottomed out," OTA says.

Coal companies owned or controlled by the major oil companies will account for about 48 percent of the total domestic coal production by 1986. As recently as 1976, coal production from oil or natural gas company subsidiaries by comparison, amounted to only 1.6 billion tons.

OTA concludes that "neither Congress nor the president has yet articulated a comprehensive and consistent coal policy." While the elements of a national coal policy are in place, OTA says achieving it will not come quickly or inexpensively.