Developers of a proposed CVS pharmacy learned on Wednesday that the Conservation Commission will hire an engineer at their own expense to double check wetland boundaries on the site.

Representatives from two firms working on the project asked the commission to confirm where the wetlands are on the 1.78 acre-parcel.

The request was brought forth to ensure that future plans for the site don't encroach on the wetlands.

Located at the corner of Route 6 and Front Street, the property is home to the historic Captain Hadley House and is across the street from Cumberland Farms. Plans call for the relocation of the Captain Hadley House to make way for the construction of a 14,600-square-foot-building with a drive-thru.

At the meeting, professionals from the civil engineering firm Bohler Engineering and the Plymouth-based LEC Environmental Consultants asked the commission to certify wetland boundaries on the property.

“We’re seeking confirmation of their accuracy,” said Josh Swerling of Bohler Engineering.

Swerling showed commission members a map of the wetlands drafted by his firm.

Chair Norm Hills said because other sources than town and state wetland maps were used to create the plans, another engineer should check the site.

“You are asking if the boundaries are correct. I’m not sure at this point in time if we can verify that going forward,” Hills said, adding that developers would need to pay for the work. “If the engineer comes up with the same [wetland] lines then you’re fine.”

Swerling asked for an estimate of the cost of the engineer from Hills and when the work will be done.

“I can’t tell you how long it will take us to get the information you need,” Hills said. “I can get you an [estimate] in a couple of days. Getting an engineer identified and under contract will take longer.”

With only two commission meetings left in the year, Swerling asked that, if possible, the report be done next month.

The commission’s next meeting is Nov. 12 in the Marion Town House at 7 p.m.