GROTON — Plans by a local businessman to open a karate studio on Main Street ran into trouble at last night’s Zoning Board of Appeals meeting when neighbor Workers Credit Union voiced opposition to the project.

“It doesn’t take a rocket scientist to see that this plan just doesn’t work,” bank attorney John Gallant told members of the board in no uncertain terms.

At issue was a proposal by Michael Luth, owner of Luth’s Family Karate of Pepperell, to relocate his business into a building at 306 Main St.

But in order to better accommodate his martial arts school, the interior of the existing building there would have to undergo some alterations and to fit a pair of handicapped bathrooms and other spaces, an 1,800 square foot addition would need to be constructed in the rear.

Crucial to the success of the relocation will be parking. Luth said that through an existing easement, up to 36 spaces would be shared between himself and Workers Credit Union next door.

Access to the parking lot is shared between the two as well as a doctor’s office located in a third building.

According to Luth’s engineer, Robert Oliver, the issue had gone before the ZBA due to the fact that the property has already been judged as nonconforming to the town’s zoning bylaws and building the addition would only increase that condition. As a result, there was a need for the board to approve the variance to the site’s western setback upon which the addition encroached.

Calling the proposed karate studio a benefit to the town, Oliver said that the business would not pose an undue burden on local traffic or the environment.

Finally, Oliver said that with an existing agreement with next door Workers Credit Union, 36 parking spaces on the property were shared with 26 being reserved to the bank and 10 to his client.

Although the Karate business by law would require up to 17 spaces, Luth claimed that only 10 would really be needed and that because most of his hours of operation would take place when the bank was closed, there would be enough room in the parking lot for anything more.

That argument, however, was challenged by the bank which was concerned about those times when the two business’s hours overlapped as well as the possibility of “stacking problems” as cars dropping off or waiting to pick up children could block the common driveway needed for its customers to access a drive-up window.

In presenting the bank’s argument at the board’s meeting of Jan. 11, Gallant said awarding Luth a variance would be “putting the cart before the horse” in that the applicant’s plans may need to change significantly in order to satisfy the demands of other review boards such as the Planning Board.

While not opposed to the karate studio per se, Gallant reminded board members that with the proposed addition, the square footage of the existing building on the site would end up three times as much with not enough parking available.

“This will cause a traffic nightmare,” concluded Gallant. “There just won’t be enough spaces. The building plans will have to change.”

The board, Gallant advised, should delay its vote until after the Planning Board had reviewed the site plan and made its recommendations. Only then would the ZBA have the information it needed to make an informed decision.

However, board member Jay Prager pointed out that it was not the ZBA’s responsibility to consider issues such as parking but only the setback question. Should there be any changes made by the Planning Board at odds with the Zoning Board’s decision, the issue would simply come back before ZBA for another vote.

In the end, board members followed Prager’s logic and voted 5-0 in favor of the special permit