RUMFORD – Following months of review and years of planning, a 306-unit subdivision near Black Mountain, the largest in Rumford’s history, was approved by the Planning Board on Wednesday night.

Cissel Enterprises LLC, owned by Lem Cissel, the owner of Scrappers Domaine, plans to build or have built 145 residential units in multifamily buildings, 23 houses in common-land cluster arrangements, 28 houses in small-lot clusters, and 112 single-family homes with lot sizes ranging from 20,000 square feet to two acres. The development would be situated on more than 400 acres on Isthmus Road. About 146 acres will be common land.

Cissel, a Maryland businessman who came to the area about four years ago, purchased the land near Black Mountain soon after he arrived.

The Planning Board approval requires an OK of the project by the Maine Department of Environmental Protection as well. That must be submitted by the state agency by February, Cissel said after the meeting.

According to the 10-page summary of facts submitted by Bob Berry, an engineer from Main-Land Development of Livermore Falls who has been working on the project, Cissel estimates the total cost of the plan at $5 million.

Cissel thanked the board for the months of work it devoted to study and review the project.

“I hope it will turn into something to be proud of,” he said.

Every unit in the project will have some type of view of Black Mountain. Most are expected to be second homes, Cissel said.

Before any building starts, he said, a road must be built according to town standards. That could be done in 2007, with the possibility of starting construction the next year.

How much building will actually be done depends on interest rates and the market, Cissel said.