TYNGSBORO — The town has officially ratified a payment-in-lieu-of-taxes agreement for a proposed solar-panel project that should bring in $631,462 over 20 years.

The agreement with Tyngsborough Solar, LLC is based on the value of equipment, assessed value of six parcels of land, and the increased tax rate for each of the 20 years in the agreement.

The project, to be installed on the site of the former Charles George Landfill between Cummings and Dunstable roads, will bring in an average of $31,573 per year for the town, according to a letter from the town administrator.

The project will be built on five land parcels in Tyngsboro and one in Dunstable, leasing roughly 70 acres of land.

In addition, the solar company has agreed to pay no less than $215,000 in back-taxes that the owners of the Charles George Landfill had not paid for decades.

That number doesn’t include some $700,000 in interest and fees which the town later waived.

Selectmen voted for the agreement at their meeting last Monday.

“We looked at what other towns had been doing, we got an engineer peer review of that land to make sure that the structures would not comprise the (landfill) cap,” said Selectmen Chairman Rick Reault. “There’s going to be continued inspections, so there’s measurements in place (that) in case anything does go wrong, it’ll be fixed.”

In Dunstable, officials are still working out a payment-in-lieu-of-taxes agreement but the town should receive about $25,000 in back-taxes for the single parcel, according to the Citizens Energy group that set up the Tyngsborough Solar project.

Yet the project — and all the revenue it carries — still cannot go through until the state Legislature lifts the cap on net-metering credits that help keep these solar projects running.

“We look forward to the project moving forward,” said Citizens Energy spokesman Brian O’Connor.

He noted the “hold up” on Beacon Hill, hoping that it will get cleared up so that the project can begin.

In Tyngsboro, the project does not solve the overdue taxes for other parcels on the old Charles George Landfill, which may have increased since the $368,941 the treasurer’s office estimated in December 2014.

Reault said he anticipates the town will be pursuing back-taxes on properties that have reached large amounts, just like the Charles George land.

An independent study suggested that Tyngsboro needed to speed up its tax-delinquency process, selling tax-title properties that could free up more development space.

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