LAWRENCE – A prominent city contractor is rejecting allegations by Attorney General Maura Healey that his workers improperly handled asbestos hundreds of times while working on the reconstruction at Greater Lowell Technical School in 2014 and 2015. Healey alleges the contractor exposed students and staff to the carcinogen.

Two state environmental agencies that visited the school -- one at Healey's request and the other in response to complaints from school employees -- reported finding no evidence that the contractor, RM Technologies, had mishandled asbestos while working as a subcontractor on a $65 million reconstruction of the school.

The school's superintendent and the chairman of the School Committee said they were bewildered by Healey's allegations.

Healey made her claims in a lawsuit filed in Suffolk Superior Court in Boston, where she is seeking $25,000 in fines for every day the violations occurred over the two years.

The suit alleges that RM Technologies “failed to contain work areas while performing asbestos work, allowed pieces of asbestos-containing waste material to remain dry and uncontained in many places throughout the school, conducted asbestos work without supervision by the project manager and failed to clean up visible debris after performing asbestos work, among other violations."

The suit also alleges that RM Technologies at least 12 times did not allow access to its work by another contractor the school hired to monitor the Lawrence company as it removed the asbestos. 

RM Technologies is owned by Rafael Guzman, who is active in Lawrence politics and last year led an unsuccessful effort to recall Mayor Daniel Rivera. The company has offices on Franklin Street, where the recall was headquartered. 

Healey's 17-page lawsuit does not cite a source for the allegations -- which are numerous and detailed -- including who her investigators may have interviewed and what documents they reviewed. A spokeswoman for Healey declined several times to say whether the attorney general's investigators visited the technical school while the asbestos was being remediated or after the work was completed. The school is in Tyngsborough,

The spokeswoman, Chloe Gotsis, said only that inspectors for the state Department of Environmental Protection visited the school at Healey's request, but said they arrived months after the matter came to Healey's attention.

By then, if workers for RM Technologies were mishandling asbestos, it was too late to document it, said Ed Coletta, a spokesman for the Department of Environmental Protection.

"By the time we got there, there was nothing to investigate," Coletta said. "There were no ongoing violations."

An environmental engineer for the state Department of Labor Standards visited the school on Nov. 25, 2014, while the work was in progress. In a four-page report, the engineer, Janet McKenna, also reported finding no violations, although she noted broken edges on wall panels containing asbestos in three rooms. She said the panels were scheduled for removal.

Asbestos was common in insulation, tiles and other building materials until it was banned in the 1970s. It remains widespread in buildings nationwide but poses no danger unless the materials are shattered, which can cause the asbestos to go airborne. Regulations governing its removal and disposal are specific and strict. 

Guzman said his workers “followed all the regulations, all the protocols” set by the Department of Labor Standards for doing asbestos removal. He said the agency inspected his company's work during more than 15 visits over the 18 months it was on the job, usually in response to a complaint, and left satisfied each time.

“They never wrote us up,” Guzman said. “They never gave us a citation, a warning, that we were doing something wrong. That's because we were not doing anything wrong.”

Roger Bourgeois, the school's superintendent, said the suit "caught him by surprise, just because of the level of scrutiny that was going on with regard to the project.... The complaint is the first indication we had than there was any issue."

Ray Boutin, chairman of the committee that oversees the school, agreed.

“We had the state Department of Public Health at our school a number of times,” he said. “They never found any issues.”

The Department of Public Health has no authority over asbestos removal and did not investigate concerns about how the material was being handled at the school, said Tom Lyons, a spokesman. Health department investigators visited the school three times in 2014, but focused on air quality issues such as levels of carbon monoxide and dioxide, airborne particles and volatile organic compounds, Lyons said. 

The agency found air quality in the school was within or close to recognized standards but suggested a few ways to improve it, including installing more efficient air filters on ventilation units in classrooms and on rooftops. It also recommended better barriers between occupied areas of the school and areas where construction was occurring.

Boutin also said a company hired by the project's architect to monitor RM Technologies “never found anything wrong with any of the areas.”

The asbestos remediation was monitored by Universal Environmental of Framingham. Jason Becotte, an inspector for the company, would not comment on Healey's allegations that RM Technologies botched the asbestos removal, citing the pending lawsuit.

The $65 million reconstruction of the technical school is being done by Consigli Construction Co. of Milford, which hired RM Technologies as a subcontractor to do the asbestos abatement.

Healey's suit alleges workers for RM Technologies “left ragged pieces” of materials containing asbestos in classrooms and hallways. It said the workers twice caused “desks, lamps and computer equipment” in a classroom for special needs students “to be covered in dust,” and left the cleanup to faculty and staff. It alleges workers often failed to water down asbestos material, as required to keep particles from going airborne.

The complaint alleges that for several weeks in July and August 2014, RM Technologies workers “permitted multiple bags of dry, broken, uncontained (materials containing asbestos), including small chunks and dust, to sit in open plastic bags in a hallway on the first floor of the school in an area where school faculty and/or staff walked as part of their daily work.”

At least 327 times, the workers cut, drilled or removed pegboard and plaster containing asbestos in rooms and corridors that were not sealed to prevent airborne asbestos from escaping, as required, the suit alleges.

At least once, workers allowed contaminated debris to be tossed into a dumpster rather than properly packaging it and carting it to facilities designated to dispose of contaminants, the lawsuit alleges.

“The fact is, that's not true,” Guzman said about the allegations.

“We've been doing abatement since 1994 and we've never had this problem before,” he said. “Our guys are trained, licensed and they follow protocol.... (They're) directly supervised by independent environmental consultants who work for the school system. We don't do anything without their approval. The watchdog agencies ... they were supervising us.”

Guzman said Healey's suit is rooted in complaints to her office by at least one teacher at the school who he said is now suing RM Technologies. He could not name her.

The suit was filed by Louis Dundin, an assistant attorney general in the office's environmental protection division.