The Board of Light and Power-operated Marquette Energy Center consists of three 18-megawatt reciprocating internal combustion engines that are dual fueled by natural gas and fuel oil. Shortly after operations began in August 2017, more than a dozen Marquette Township residents complained about noises coming from the MEC, which is located along Wright Street. (Journal file photo)

MARQUETTE — The Marquette Board of Light and Power is a step closer to potentially finding a solution to the noises and vibrations stemming from its energy center along Wright Street.

BLP Executive Director Tom Carpenter said international emissions and noise management company Innova Global will begin an onsite evaluation next week near the Marquette Energy Center, or MEC. The company ordered sound mitigation materials, which he said are anticipated to arrive next month, with a final construction date set for May.

Shortly after operations began at the MEC in 2017, over 20 complaints were submitted by Marquette Township residents who live near the facility about high- and low-frequency sounds as well as vibrations believed to be coming from the energy center.

Representatives from Innova conducted a study several months ago at noise-sensitive receptors near the MEC to quantify sound levels of each source. Testing was also done near residential areas.

Innova discovered that the major low-frequency noise contributors are largely from the building walls and roof of the engine hall. Some of the radiators are also a part of the problem.

“So, our recommendation, first and foremost, is the building envelope,” Art Cooper, senior acoustic engineer of Innova, previously said. “We propose to retrofit the existing wall and roof with a new design, a heavier design that will help keep the sound in and not let it come out; the building ridge vent, as well. We would remove the existing vent and replace it with an acoustic system, a series of hoods that point to the north, which is away from the bulk of the residents. And finally, looking at some radiator noise control.”

In January, the BLP Board of Directors unanimously approved allocating an amount not to exceed $2.9 million to address noises and vibrations emanating from the facility.

BLP staff recently received a proposal from acoustic consultant Shiner & Associates which proposed to assess the area for around $7,700, Carpenter said.

“During all of these discussions, we’ve had a number of concerns — not only (about the) noise, but vibrations,” Carpenter said. “(Shiner & Associates) have explained that there’s a way it’s actually noise related, and not going through the ground.”

The company will do a baseline measurement, Carpenter continued.

“We need to somehow prove if we’re shaking the ground or not. This is a way to it. It’ll be a good way to prove that our sound mitigation will be a good fix,” he said.

Shiner will conduct the study with the MEC shutdown, then start each one of the three Wartsila-manufactured engines in the facility, one-by-one.

“What we expect to find is what we’ve been being told by the sound engineers (at Innova),” he said. “We don’t have any reason not to believe them, but we just want to validate it with actual measurements.”

Sargent & Lundy, an engineering firm that’s also worked alongside the BLP on the matter, has been assessing the high-pitch whining noise neighbors have complained about. According to BLP staff, Sargent & Lundy is currently looking into whether there’s efficiency motors that can be used in the MEC to ease the issue.

Marquette Township resident Mary Thorrington said the vibration hasn’t been as noticeable since there’s been high snow and ice levels, which Carpenter said points to the issue being sound-travel related, rather than the MEC’s engines shaking the ground.

Jaymie Depew can be reached at 906-228-2500, ext. 206.