A group of Searsport and Stockton Springs residents have ramped up their opposition to a proposed liquefied petroleum gas terminal at Mack Point, filing an appeal in Kennebec County Superior Court, Dec. 2, for a review of the Department of Environmental Protection’s approval of the project.

DCP Midstream, a subsidiary of ConocoPhillips and Spectra Energy, is seeking to build a 22.7-million-gallon propane storage tank and related infrastructure on a parcel of land to the east of the Mack Point cargo terminal.

The project received DEP approval in October, but the petitioners say too many factors were not addressed in the agency’s decision.

The advocacy group Thanks but no Tank is named as a petitioner along with 22 private citizens — including residents with abutting land or views of the proposed terminal site, and also business owners — who believe the terminal would hurt their livelihoods. All of the named citizens are identified as members of TBNT.

The appellants allege four potential effects of the development that were either insufficiently considered or that they claim would be in violation of the Natural Resources Protection Act or Site Location Law. The four counts are:

Project impacts to scenic and aesthetic resources and visual character will violate NRPA [Natural Resources Protection Act] and the Site Location Law [Site Location Development Act].

• Project impacts to recreation and navigation will violate NRPA and impacts to existing uses, public safety and welfare will violate the Site Location Law.

• Air pollution from non-point sources will violate NRPA.

• Noise pollution from the terminal and associated truck and rail traffic will violate the site location law.

On the matter of scenic resources, the group alleges that the department’s visual impact assessment used insufficient data to reach the conclusion that the project “will not have an unreasonable adverse effect on the scenic character of the surrounding area.”

The conclusions, the petitioners say, were based on limited vantage points, and considered a three-mile radius, when the project would be visible from further away, primarily from the bay. The petitioners also say there was no consideration of potential clear cutting of the land or the effect of lighting at the terminal.

On the second count, the petitioners expressed concern about so-called “exclusion zones” — wide, protected areas around boats — given to propane tankers, which are forecast to make deliveries to the proposed terminal six times per year, and the effect of these on recreational boating, and safety.

Additional counts charged that the approval did not consider emissions from trucks and rail cars, and did not give enough evidence to support findings on potential noise levels coming from the facility, including truck traffic.

Speaking on Dec. 6, Peggy Bensinger of the Maine Attorney General’s Office said she had not seen the appeal yet.

“We’ll review the allegations in the appeal and we will be defending the Department of Environmental Protection’s decision,” she said, adding, “I can’t say any more without reading it.”

Although she did not offer any additional comment on the specifics of the appeal from TBNT, Bensinger did explain in general terms how the appeal process usually works. Typically with court appeals, she explained, the agency has 30 days to assemble the record of the permitting process, including all materials that contributed to DEP’s approval.

The appellants would then have 40 days to submit a brief supporting their charges, after which DEP and the permit holder — DCP Midstream — would each have 30 days to file a brief in response. The appellant would be allowed to file a final brief before the case was scheduled for oral argument.

Bensinger said the courts typically give “considerable deference” to the agency on questions of factual findings, but not on legal questions.