AUGUSTA — The 4-month-old LePage administration announced a Cabinet shake-up today, with Darryl Brown resigning as commissioner of the Maine Department of Environmental Protection amid conflict-of-interest questions and the head of the state’s economic development agency abruptly vacating his post.

Gov. Paul LePage said Brown has accepted an appointment as director of the State Planning Office. The governor also said Philip Congdon has resigned as commissioner of the Department of Economic and Community Development.

While no reason was immediately given for Congdon’s departure, conflict-of-interest questions have swirled about Brown’s appointment to the state’s environmental regulatory agency since his name was placed in nomination by the newly elected Republican governor in early January.

Today’s announcement that he was stepping down came after Attorney General William Schneider released a letter to Brown saying income Brown has derived from his business, Main-Land Development Consultants Inc., may create a conflict under state and federal law.

Schneider’s letter also said that if Brown couldn’t produce documents showing the absence of a conflict, he’s unqualified to serve. That produced a problem for Brown, because Schneider emphasized that any documentation he provided to the attorney general’s office would be considered public. Release of those records could hurt Brown’s business, which consults for other companies on land-use issues, said Brown’s attorney, Clint Boothby.

Brown called the whole matter “silliness” and said the law was being applied more scrupulously in his case than that of others who previously held the post.

“If you looked at all the commissioners prior to me, I have to believe that many of them would not have passed this test,” Brown said in an interview. “Anybody with any kind of experience in the kind of management that’s required at a department like the Department of Environmental Protection would be left out of the process, would not be able to be involved. That’s where I believe the silliness comes in.”

The LePage administration said it would seek to amend the state law on conflicts of interest. He views the law as blocking Brown from serving as commissioner.

“It is unfortunate that Maine law is so inflexible that it can be read to prevent good people from serving,” LePage said in a statement. “This is another example of the costs of Maine going beyond federal standards. I have discussed this issue with legislative leaders and am pleased that there is support for legislation to fix this problem.”

In the meantime, LePage said he is now obliged to ask members of the state Board of Environmental Protection to submit information related to their individual sources of income from 2009 onward.

“Regrettably, this step is required to allow me to meet my constitutional obligations to faithfully and equitably execute the laws,” LePage said.

Congdon, an engineer by background, raised eyebrows during his confirmation hearing early this year when he told lawmakers his economic development experience was “thin,” and said he hadn’t thought too much about revitalizing rural Maine when asked about it.

Messages left with his office were not immediately returned Wednesday afternoon. LePage’s spokeswoman, Adrienne Bennett, would not comment on why Congdon resigned and said only that his resignation was immediate and the governor’s office would have no further comment.

LePage also announced today he would nominate Robert Winglass, a former U.S. Marine officer who also served in the Maine House, as commissioner of the Maine Department of Labor. The governor said he’s appointed David Emery, a former Republican congressman from Maine, as deputy commissioner for the Department of Administrative and Financial Services.