DEVENS -- After ceding to a request from one firm to postpone its public hearing, to a later date, the Devens Enterprise Commission convened the second public hearing on its docket last Tuesday night.

Bristol-Myers-Squibb asked for a continuation of its scheduled Level II site plan permit application from Oct. 30 to Nov. 7. "Staff recommends granting the request," Director Peter Lowitt said. The board agreed.

Next, DEC members heard from and asked questions of representatives from 112 Barnum LLC and Saint-Gobain, the firm renting part of the vast building built and formerly occupied by Evergreen Solar. Ultimately, that hearing would be continued too.

David Mackwell, of Kelly Engineering Group. Inc., represented the applicant. He was accompanied by company principal Robert Flynn, two of the builders working at the site and Gregory Tocci, of Cavanaugh Tocci Associates, an acoustics consultant hired to work with DEC's sound consultant.

Although the permit application, to add a loading dock to the building and amend the site plan accordingly, has little to do with sound, most of the discussion centered on it. Noise, actually, but not from the loading dock.

112 Barnum LLC, an arm of Calare Properties in Hudson, bought the building last spring after it was abandoned by Evergreen, a manufacturer of solar panels. Loud noise from rooftop scrubbers and exhaust vents and middle of the night fuel deliveries caused no end of controversy as residents of a nearby neighborhood in Harvard complained vigorously. The result was a protracted noise mitigation process and subsequent tightening of permit rules and sound regulations.

Now, before DEC issues a permit, the applicant must not only follow "sound level measurement protocols" to the letter, but must also "prove" the measurements are correct, Lowitt said, and that mitigation, if any, is effective.

Sketching application criteria for the Barnum Road facility, he said the 23.2-acre site is located "fully within the trade and railroad zoning district, with 385 parking spaces, 18 loading docks and 366,000 square feet of interior space.

Mackwell said adding a loading dock and moving a set of outside stairs requires "minor modification" of the site plan, but most of the proposed changes have to do with "proper reallocation of internal space." Explaining why another loading dock is needed, he said the plan calls for re-dividing building space to accommodate the current tenant and provide dock access for another renter later on.

"It was fully permitted years ago," Mackwell said of the building. The applicant also requests "a couple of waivers" since there's no new construction and no added lighting. A sound expert was hired to work with DEC's sound consultant "to ensure all standards are met," he said.

DEC members asked a few questions, with a half dozen representatives there to answer them.

For example, Bill Marshall asked if air tanks outside the building were removed. The answer was yes.

Jim DeZutter asked what the tenant's company, Saint-Gobain, makes on site and if "toxic" chemicals are used in the manufacturing process.

Speaking for Saint-Gobain, which occupies 190,000 square feet of the building, Eric Lévesque said there are no toxins and no product manufacturing, per se.

In business since the 1600s in France, when it was well known in the glass trade, Saint-Gobain is an international company that makes "substrata" for LED lights at the Devens facility. But not the lights themselves. "We grow the sapphire crystals and send them to our customers," Levesque said. The finished product that leaves Devens is a disc that looks like a silver CD.

"I assume there's more to the story," member John Oelfke said. Traffic? Noise? Do the scrubbers stay or go?

The answers to his questions, in summary, were that the business generates "low truck volume" of only about 10 trucks a day and operates only during normal business hours, and a normal business week, which is also when fuel will be delivered.

As for the noisy scrubbers, commissioners were told that most of them were gone and neither the company nor prospective tenants plan to use those that are left. However, if someone comes along who wants to start using the scrubbers, the owner will have to come back to DEC with a request to do so.

"How will you comply with our performance standards?" Lowitt asked.

Again, he was talking about noise.

Tocci, the sound consultant, said he's working on it, by the book, starting with a seven-day evaluation of existing background, or "ambient" sound, followed by evaluation of the building design and business operations to ensure that sounds inside or out do not exceed permit parameters, or 5 decibels above the ambient sound levels.

In addition, "we've been asked to measure gas delivery sounds," Tocci said.

Trucks will deliver propane gas, but on-site systems rather than pumps will propel the pumping into 9,000-gallon bulk tanks on the trucks. Deliveries will be only during normal business hours. Plans also call for installation of an 11,000-gallon nitrogen tank, Tocci said, and the company intends to keep the "sound curtains" Evergreen installed at the pumping stations.

Sound-deadening walls will also stay put, he said, and may be upgraded later if necessary.

As for the new bay door, which is what the permit is for, it will be closed when not in use and it's weather sealed, Tocci said. Forklifts will be operated inside the building and inside the trucks, but not outside, he said. And trucks backing up to loading dock can't idle for more than five minutes, per state law. "The lift sounds shouldn't be audible outdoors," he said.

"So, no sound data yet?" Oelfke asked.

Not yet, he was told. The initial evaluation should take about seven days, with results in about two weeks. "We'll come back," Tocci said.

The hearing was continued to DEC's next meeting on Nov. 8 at 7:30 a.m.

As of the first part of the hearing, the new business at Evergreen's old site had apparently steered clear of stirring up community noise. With the 30-day comment period over, there were no letters, Lowitt said. And nobody came to the public hearing.