OXFORD — The go-ahead to build a $12.2 million solar energy facility may hinge in part on a snake.

The Maine Department of Environmental Protection is requiring Dirigo Solar of Portland to hire a herpetologist or arrange with the Maine Department of Inland Fisheries and Wildlife to survey a section of the site for the presence of eastern ribbon snakes.

Plans call for installing 30,000 solar panels/modules on 38 acres between Route 26, Number Six Road and the Oxford County Regional Airport to produce 9.2 megawatts of electricity to be sold to Central Maine Power.

Dirigo officials describe the company’s mission as leveraging technology cost reductions to lower the cost of power for Maine homeowners and businesses, with locally generated, clean energy.

Construction is expected to begin this summer, and the farm is anticipated to be operational for 30 years or longer.

The Planning Board approved the project site plan review May 9.

The DEP is requiring that if an eastern ribbon snake is observed and documented during the survey, the applicant must submit a draft deed restriction to the DEP that will protect the 100-foot vegetated buffer around the snake habitat. Once approved, the deed restriction will be recorded.

According to a report by the New Hampshire Fish and Game Department, the species is near the northern limit of its range in New England and is listed as a “species of special concern” in Maine, Vermont, Connecticut and Rhode Island because of uncommon and localized populations of the snake that appear to have declined.

The New Hampshire agency’s report also notes that the presence of ribbon snakes may indicate “high quality wetland habitat that could support other species of conservation concern such as spotted turtle, leopard frog and blue‐spotted and four‐toed salamanders.”

The snake is described as slender and semi‐aquatic often observed near the edges of emergent marshes, wet meadows, scrub‐shrub wetlands, beaver impoundments, bogs, river and stream floodplains, and vegetated shorelines of ponds and lakes.

“Ribbon snakes generally avoid deep water but will swim readily along the surface,” the report said.

In addition to investigating the presence of the eastern ribbon snake, the DEP is requiring the applicant  to retain a third-party inspector, conduct a preconstruction meeting, retain a meadow area where the solar array is constructed and take all necessary actions to ensure there is no noticeable erosion of soil or dust emission on the site during construction and operation.