IF ANY OF VIRGINIA'S state legislators still regard conflict-of-interest and financial-disclosure legislation as unnecessary, they should take a good look at what's been found out about certain state officials who inspect coal mines and oil wells. Inspectors are themselves being inspected--as well they should be--in the wake of disclosures that Virginia's chief mine inspector and two other mine inspectors owned stock in a coal company, and that an oil well inspector owned stock in an oil drilling firm. That's just plain wrong--and Gov. Robb has acted swiftly to make the point.

While these conflicts of interest are clear, some of the language in the laws is not. The state's investigation began last week, when a report in this newspaper noted that the chief mine inspector owned $19,000 in stock in the Pittston Co., corporate parent of a company that owns a mine in Southwest Virginia in which seven miners were killed on June 21. Only then were Gov. Robb and other state administration officials informed by the state attorney general's office that a law forbidding stock ownership applied to a "mine inspector"--but not to a "chief mine inspector." Fortunately, the chief inspector, while found not in violation of any law, chose to sell his stock anyway. He has been removed from the state's investigation of this disaster.

This week, the three other cases turned up. The governor wasted no time stripping these officials of their regular duties and ordering them to sell their holdings. In addition, Mr. Robb referred the mine inspectors' cases to authorities to determine if they should be charged with violating a state law forbidding mine inspectors from holding stock in any coal company.

Here again, the law governing the two mine inspectors apparently does not extend to oil and gas company holdings. Still, the administration ordered the oil and gas inspector to sell his stock in a maker of parts for oil well drillers, and reassigned him. The mine inspectors have said they were unaware of any stock-ownership prohibitions. But state Secretary of Commerce Betty J. Diener doesn't accept this explanation: "Each of them has a book of all the state's mine regulations that they carry around with them at all times," she said. "When you carry that book around with you every day, it's hard to say that you didn't know that the law was on the books."

And when the legislature convenes next year, it should see to it that those books read a lot more clearly than they do now.