Groton - While retailers in downtown Mystic understand that their shopping district still will be under construction during Memorial Day weekend, concern is rising that the situation won't be much better by Independence Day.

The streetscape construction project that was on schedule in March is now a month behind, and the contractor, Pettini Contracting of Mystic, has asked for a 34-day extension. The project to install new sidewalks, utilities and aesthetics along West Main Street and part of Water Street was to have been completed by June 30.

"The town has not agreed to any extension at this point," Michael J. Murphy, the town's project administrator, said in an email Friday. "The matter is under review at this time."

Murphy said Pettini will be asked to explain how the company would expedite work along West Main Street to minimize the impact on local businesses.

"Every effort is being made by the town to get the major work done on or before June 30," Murphy said. "We expect to respond formally to Pettini's request for the extension next week."

Rick Norris, the on-site project manager, said the most significant incomplete component is the installation of utility conduits that will span West Main Street from its intersection with Pearl Street to Water Street at Bank Square Books. The trench and the six, 6-inch concrete-encased PVC pipes would extend about 100 feet below Water Street.

Norris said one of the obstacles has been the discovery of low levels of lead in the soil of the trench where the conduits will rest. He said the water that came up with the dirt as the trench was being dug had to be filtered before it could be discharged.

Tricia Cunningham, president of the Greater Mystic Chamber of Commerce, said the extension request is cause for concern for merchants.

She said locals who shop, dine and spend leisure time in downtown Mystic boost the economy through the spring and fall. She said traffic that is being rerouted because of the bridge closure is causing people to change their patterns.

"Locals are changing habits," Cunningham said. "But now is when we really need people to come back (downtown). We're at the last stretch, the hardest part. It's so close to the summer season that keeps the businesses sustained. But we count on the locals to get us through the rest of the year."

There are financial ramifications for the contractor if the main project work is not completed by the deadline.

c.potter@theday.com