The debate over a proposed asphalt plant, already fueling a fiery campaign for three council seats, intensified on two fronts this week.

Monday, as nomination papers became available for three seats on Gorham’s council, a declared challenger charged that a councilor should not be voting on asphalt plant issues because of a conflict of interest.

Tuesday, two Boston groups, Toxics Action Center and GreenCorps, along with a home-grown anti-asphalt group called Concerned Citizens of Gorham, held a press conference in front of the Gorham Municipal Center. The purpose was to bring public attention to their opppsition to the asphalt plant and quarry proposed in Gorham by Shaw Brothers Construction Inc. Before the press conference, a leading opponent of the asphalt plant announced his candidacy for the council.

The construction company’s proposed quarry and asphalt plant on a 125-acre site on Mosher Road has prompted an emotional reaction from citizens. Much of the site is wooded and zoned industrial. The asphalt plant would be on 2.9 acres. Shaw Brothers bought the property from Lachance Brick, which kept a building and a portion of the property to sell bricks. The brick company previously manufactured bricks at the site.

Shaw Brothers is planning initially for a $3 million portable asphalt plant, which would be replaced at some point by a $10 million permanent facility.

In July, the Gorham Town Council requested that the planning board hold a public hearing and recommend changes to land-use ordinances that could impact that project. Proposed changes under consideration govern mineral excavation and noise. Critics are charging that the changes would help the asphalt plant win approval, while the town says it needs updated and clarified ordinances.

In that July council meeting, Burleigh Loveitt, an incumbent whose term expires this fall, voluntarily stated that his son worked for Shaw Brothers Construction Inc., but other council members decided Loveitt’s son’s job did not pose a conflict of interest that would prevent him from voting on the project. Councilors Phil Dugas and Jane Stinchfield Willett were absent.

Dave Babino of Longmeadow Drive, an opponent of the Shaw proposal but not a member of Concerned Citizens of Gorham, said Tuesday he believed Loveitt should have abstained from the vote that sent the request to the planning board.

“He definitely had a conflict of interest,” said Babino. “He should have abstained.”

Babino said he intends to put his “name in the hat” as a council candidate.

Babino plans to air his concern at the next council meeting, when it could consider the planning board’s recommendation about ordinance changes. “I’ll be there,” Babino said. “I’m going to be vocal.”

Loveitt, who said Tuesday he’s undecided on another run after 35 years of public service to the town, said he’s willing to discuss concerns about his July vote. He refuted conflict allegations.

“I purposely brought the subject up,” said Loveitt, a former council chairman and now vice chairman, about disclosing his son’s employer. “His job doesn’t depend on my vote.”

Norm Justice, chairman of the council, is seeking re-election this year, and he defended Loveitt this week. “It’s absolutely not a conflict,” Justice said.

Justice said Loveitt made a public disclosure and put the question to the council, which approved Loveitt’s participation. “It’s a real stretch,” Justice said about the conflict of interest concern.

Dugas, a councilor whose term is also expiring, has served four terms and is contemplating another run. Dugas said he favored the proposal by Shaw Brothers.

“I really think it would be a benefit to the town of Gorham to have the asphalt plant here,” said Dugas, who said it would help the elderly as far as taxes were concerned.

Matt Robinson, a former town councilor, is running again after not seeking re-election a year ago. “It’ll be a campaign issue,” Robinson said last week about the asphalt plant.

Robinson, who also sees a need to bolster tax revenue, favors the project. He said it’s proposed for an industrial zone and the industry is heavily regulated by environmental laws. Robinson said the concerns about noise and hours of operation could be resolved locally.

“I’m ready to rock ‘n’ roll,” said Robinson about launching his campaign.

Dave Homa, a member of the Concerned Citizens of Gorham, said before the group’s press conference that he has taken out nomination papers for a seat on the council.

“It’s not about me. It’s about the direction of the town,” Homa said.

Making his third bid for a council seat, Homa singled out the need to update the comprehensive plan. “We need to balance residential and industrial uses,” Homa said.

Homa said the asphalt plant is the biggest issue in town now. “I don’t see that as an asset to the town at the current location,” Homa said.

At the behest of the Concerned Citizens of Gorham, staff of the Toxics Action Center and GreenCorps in Boston were in Gorham to campaign against the asphalt plant.

Emily Stone of the Toxics Action Center in Boston said GreenCorps is a “field school for environmental organizers that trains young people to take leadership positions in the environmental movement.”

The two groups have been door-to-door canvassing in Gorham, seeking signatures to support their opposition to the asphalt plant.

“Concerned Citizens of Gorham asked for our help,” said Dan Gradess of the Toxics Action Center.

The groups organized Tuesday’s press conference. Speakers at that conference included Liz Gary of the Toxics Action Center and Gorham residents Russell Sprague, Jennifer Everett and Deborah Cassidy.

Sprague, a member of Concerned Citizens of Gorham, said the group has a core of about 20 people. But, Sprague, said 500 people had signed a statement, which would be presented to the town.

The planning board, which is reviewing the company’s request for the quarry and the asphalt plant, could vote Monday on its recommendation to the council about ordinance changes that could impact the proposed plant.

Sprague is questioning the process of town government changing ordinances while it’s considering a request. “It will definitely be an issue,” Sprague said about the asphalt plant in the campaign.

Cassidy said at the press conference that major ordinance changes are being proposed.

“Our local government needs to slow down and be safe, not sorry,” Cassidy said.