The lattice towers Central Maine Power said it is proposing for its New England Clean Energy Connect hydropower line from Canada to Lewiston. This image, looking northwest from Wilson Hill Road in West Forks Plantation toward the proposed transmission line, also contains a photosimulation of five years of vegetation growth that is 10 feet or less in height. Credit: Courtesy of Central Maine Power

Central Maine Power’s transmission line from Canada through western Maine to Lewiston will get its second major review Wednesday when regulators look at its potential environmental impact.

The Land Use Planning Commission will hold public deliberations on whether the proposed 145-mile transmission line, called the New England Clean Energy Connect, meets the allowed uses of the land over which it would be built.

What’s at stake is a site law certification approving, disapproving or asking for changes to CMP’s planned corridor. If approved, that certification would go to the Department of Environmental Protection for inclusion in its decision on the corridor, which is expected in late October or November.

The commission’s deliberations, which may result in a decision on the project on Wednesday, could be the next endorsement following Maine Public Utilities Commission’s granting of a key permit in April.

“The P-RR subdistricts near Beattie Pond, the Kennebec River and the Appalachian Trail were the focal points of the hearing held by the commission in this matter in April and May,” said Bill Hinkel, regional supervisor for the commission.

The commission established zoning subdistricts, including the P-RR recreation protection subdistrict, to protect important resources and prevent conflicts between incompatible uses.

It plans to review a 59-page draft document detailing the issues and potential solutions tomorrow.

Hinkel said the environment department would use the commission’s certification to decide whether a CMP utility facility is allowed by special exception within the recreation protection and wetland subdistricts.

To be allowed by special exception, the applicant must show by substantial evidence that there is no alternative site that is both suitable to the proposed use and reasonably available. CMP also must show that the project can be buffered from areas that could be affected by it, for example, towers visible from a scenic site.

The environmental protection department and the commission visited several parts of the proposed CMP line on June 27 to look firsthand at how the power line might affect vegetation. They also measured areas where different heights of vegetation would be allowed to grow to help them envision how much vegetation would be cut during initial clearing for the hydropower corridor.

The project remains controversial. A citizen group recently submitted paperwork to the state’s attorney general to approve a petition for a referendum on the 2020 ballot that would undo the public utilities commission’s permit.

The Wednesday meeting is open to the public at Jeff’s Catering, 15 Littlefield Way in Brewer. The formal meeting starts at 10 a.m., with the certification part scheduled for 1 p.m.