Chicago attorney Byron Cherry has been fighting nuclear power plants for the past seven years. By his own admission, he has been "aggressive" and "pretty rough" - a thorn in the side of the nucler power industry and the government agencies that regulate it.

Now the Nuclear Regulatory Commission is trying to have him removed as the attorney for environmentalists fighting a plant in Midland, Mich., on the grounds of "professional misconduct" by Cherry.

The charges were brought by the NRC's licensing board, which is holding extensive hearings on the plant, and which also brought similar administrative charges against two NRC staff attorneys.

But the NRC lawyers said they will not present any evidence against their associates, as they are doing against Cherry. Because Cherry instigated the complaint against the NRC lawyers, they said, he carries the burden of making a case against them before a special NRC board.

At the same time, the NRC has agreed to pay as much as $25,000 to a private attorney, T. L. S. Perlman, to represent the two NRC attorneys at hearings before the special board.

Shaking his head at a pre-hearing conference here yesterday, Cherry's attorney, Milton V. Freeman, said the case is filled with "so many exceptional and unusual events that never occurred before."

He said he knows of no prior situation in which a government agency has been allowed to interfere with the representation of another parties in a case.

He also challenged the NRC's right to discipline lawyers who appear before it and asked why the NRC is paying for the defense of its own two attorneys - Milton Grossman and James Tourtellottee - while neither handling the case against them nor paying for Cherry's defense. Freeman, a partner in the Washington firm of Arnold & Porter, is representing Cherry on a pro-bono basis, without fee.

"Everyone else is being paid by the government of the United States," he observed.

Moreover, he said, the NRC attorney handling the case against Cherry - William J. Olmstead - told him the professional misconduct charges would be dropped if Cherry withdrew as a lawyer in the Michigan nuclear reactor hearing.

Cherry, in a brief filed with the NRC last March, said the charges "were calculated to intimidate my representation in this and other cases." The charges against Cherry were sparked by an exchange of letters last March, but go back to an incident seven years ago during a hearing on the same Michigan plant before the Atomic Energy Commission, the predecessor of the NRC, according to commission files.

In the exchanges, Cherry was accused by the NRC staff of "insulting and abusive comments regarding the personal conduct, ability and motivation of the NRC staff counsel."

Cherry, on the other hand, accused Grossman and Tourtellottee of having "politically resolved safety and environmental questions so as not to jeopardize" the construction permit for the Michigan reactor, and added that they had made "improper and vicious attacks" on him.

The Licensing Board to which these charges and countercharges were brought refered both sets of charges to a separate board composed of three private attorneys.

Olmstead, handling the case against Cherry, said the NRC must be able to control the conduct of attorneys appearing before it. Without a special NRC Bar - as other federal regulatory agencies have - the only way to control them is to remove them from cases if they are found to overstep the bounds of legal ethics, he said.

Thomas Engelhardt, deputy executive legal director of the NRC, said an outside attorney was needed to defend the two NRC lawyers because Cherry's charges were really brought against the staff counsel, which could not defend itself.

While the charges against Cherry, instigated by the staff, could be prosecuted by the government, the charges, he said, only "accepted them as appearing to be good on their face."