LOBATA, W.Va. (AP) _ About 150 people protested Wednesday in front of a coal preparation plant where unionized workers have been on strike for almost five months, and 53 were arrested after sitting in front of loaded coal trucks, police said.

Those arrested had to be carried off the road in front of the Sprouse Creek Processing Co. plant and were charged with obstructing an officer, state police Capt. R.G. Fink said.

Fink called the demonstration orderly, unlike last week when pickets armed with baseball bats attacked cars carrying non-union employees to work.

''Several more are standing by, so I guess they're planning to do the same thing again the next time we bring a load through,'' said Don Blankenship, president of Rawl Sales and Processing Co., which buys the coal processed at Sprouse Creek. Both companies are subsidiaries of the A.T. Massey Coal Co.

The Massey subsidiaries have offered to sign the same contract the UMW negotiated last fall with the Bituminous Coal Operators Association. The UMW says the companies' insistence on separate contracts for each subsidiary is the chief stumbling block.

UMW President Rich Trumka said separate contracts would make it easy for Massey subsidiaries to fold a company and transfer its assets to another company name, while ignoring the miners' re-employment rights.

The five truckloads of coal brought to Sprouse Creek on Wednesday came from a nearby non-union operation, Blankenship said.

He said the incident would not deter him from trucking more coal into Sprouse Creek, but said he was trying to accommodate the miners as much as possible.

''We're trying to do it slowly so they can demonstrate,'' he said.

Blankenship said the miners forced the coal trucks to stop by blocking the road with their pickups. Once the trucks were stopped the miners sat down in the middle of the road, he said.

''I guess it's a good way to protest,'' he said. ''At least it's not violent.''

The Sprouse Creek property has come to resemble an armed camp, with rifle- toting security guards stationed on rooftops and behind chain-link fences.

An estimated 800 union supporters demonstrated peacefully outside the processing plant Monday, and police estimated that between 1,000 and 1,300 showed up Tuesday.

Union spokesman Joe Corcoran said the demonstrations would continue until ''something is resolved.'' The strike began Oct. 1.