TV: VIRGINIA OPENS SERIES ON STATES

IT was with some foreboding that I approached the first program in Ted Turner's superambitious ''Portrait of America'' series, which begins on his superstation, WTBS cable, at 8:05 tonight. Had Mr. Turner not assured an interviewer in On Cable magazine that there would be no negatives along with the positives in this series of 60 hourlong documentaries. Did he not explain, ''This is like those books put out on states with beautiful photographs and descriptions of the state bird and flower. It's a Chamber of Commerce type of presentation''?

But take heart. For all the picturesque scenery, the first offering, about Virginia, is not so relentlessly upbeat as he threatened. True, this is not much of a portrait of anything, but it does offer appealing sketches of several down-to-earth Virginians in their natural habitats - from a tobacco farm to the Tidewater fishing grounds and a coal mine. And these folks are by no means all that positively inclined. The miner says, ''I just don't enjoy going down in a dark hole for eight hours a day.'' If that isn't negative enough, he adds, ''You gotta be crazy if you actually say, 'I enjoy that.' ''

That miner moonlights as a country-music performer, and to judge from the small sample here, a lot of Virginians are working at two jobs these days. Some do it out of love, like a black farmer who is also a preacher. Some do it out of need, like a custom-boat builder who has had to go to work for the Navy to make ends meet: ''No room for a small man in business no more.'' His sentiments are echoed by the captain of a fishing trawler, who is having trouble meeting the competition.

As for that promised Chamber of Commerce spirit, Hal Holbrook, the narrator of ''Portrait of America,'' provides mouthfuls of it in his homely way. He speaks of the ''pride that touches the very soul of the state,'' and reports of the boat builder, ''The dimensions of every board and plank is engraved deep in his heart.'' An uncomfortable image.

This series may not be so deep as a mine, but despite Mr. Turner's avowed intentions, the first program at least scratches the surface. If those coming up in the next three months -on Nevada, Georgia and Puerto Rico - are as easy to watch and if the residents are as believable and likable as these Virginians, the visits should not be painful.