Computer renderings of Whole Ocean's indoor salmon farm, slated for construction at the former Verso paper mill site in Bucksport. Work on the site is expected to start in August. Credit: Courtesy of Whole Oceans | BDN

BUCKSPORT, Maine — A little more than three years after losing their paper mill, the most vital piece of their town’s economic engine, Bucksport residents got their first glimpse of their next big industry — salmon.

In February, Whole Oceans announced its plans for an indoor salmon farm that would produce 5,000 tons of salmon per year on the banks of the Penobscot River.

More than 200 locals took a seat in Bucksport Middle School’s auditorium Tuesday night for their first chance to ask questions and hear directly from company officials who want to breathe new life into the shuttered mill site.

The company plans to secure a new name for its address — 1 Salmon Point, a fitting name considering this river once had the most dense Atlantic salmon population on the planet, Whole Oceans CEO Robert Piasio said.

“I would say we looked at every possible site up and down the Maine coast,” Piasio told the audience. “Bucksport and Salmon Point blew everything else away.”

Just a month before Whole Oceans’ announcement, a Norwegian aquaculture firm, Nordic Aquafarms, revealed its plans to build another massive indoor salmon farm in Belfast. Maine suddenly found itself at the forefront of a budding U.S. land-based fish farming industry.

Because wild Atlantic salmon are a protected species, it’s illegal to catch and eat them. If an American is eating Atlantic salmon, it’s effectively guaranteed to come from a farm. More than 95 percent of Atlantic salmon consumed in the U.S. comes from foreign offshore pens, primarily in Norway, Chile and Canada.

As the price of recirculating aquaculture systems technology falls, companies are building larger farms, and the industry is starting to spread to the U.S. after decades of experience in Europe. Another large-scale indoor farm is in the works in Florida.

The most common questions from locals were related to wastewater discharge. The system will recirculate 99 percent of the water that enters the tanks, but there will still be about 4 million gallons discharged each day. That’s about one-fifth of what the paper mill discharged when it was operating.

There are already discharge pipes stretching into the middle of the Penobscot River that were used by the mill.

Whole Oceans expects the pollutants released to be significantly lower than what the mill produced, though the nitrogen will be about on par, given the amount 5,000 tons of salmon would produce. Discharge limits will be set and monitored as part of the permitting process through the Maine Department of Environmental Protection.

The company also says it’s aware of the mercury contamination in the river, caused by the former HoltraChem facility upriver in Orrington, and will filter out all metals before the water flows into the tanks.

Other questions ranged from expected fish mortality rates — likely in the 3 percent to 11 percent range at the smolt stage — to how the fish would be killed — likely with percussive stunning, or striking the fish, according to Whole Oceans. Percussive stunning is believed to be among the quickest and most humane ways to harvest fish, according to the European Food Safety Administration.

Whole Oceans expects to start preparing the site for construction this fall. Developers hope to have foundations poured and the shell of the 8½-acre building up by winter, so work can continue inside the building. Construction will last 12 to 16 months, then the first salmon eggs will be brought in.

The eggs will be shipped in from a foreign company, possibly based in Iceland. Ultimately, Piasio said, he’d like to source eggs locally, but there isn’t a year-round supply available yet. It takes about two years to grow a salmon from egg to harvesting size.

The building will hold more than 60 tanks of varying sizes, with the largest about 60 feet in diameter and 25 feet deep.

The Belfast project will take a little longer to get started, because Nordic Aquafarms and the city need to complete a lengthy land rezoning process before the company can start seeking necessary permits and approvals.

Nordic hopes to start construction in 2019, and expects to produce about 33,000 tons of salmon once it’s operational.

Piasio said Whole Oceans wants to be open about its work and invite the public into the facility to learn more about how it will operate. That might involve an information center, or even an enclosed catwalk above the tanks so people can look down at the schools of salmon and get a sense of the vast scale of the operation.

“We prefer you judge us by what we do, not by what we say,” Piasio told the crowd. “We are genuine and want to be part of this community for the long term.”

Follow Nick McCrea on Twitter at @nmccrea213.

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