PORTLAND – When Christian MilNeil spotted layers of oyster and clam shells at a construction site on Hammond Street, he thought he had found a midden.

Most people wouldn’t be able to tell a midden from a mitten, but MilNeil knew that a midden is essentially an ancient garbage pit — shells and other waste left behind by American Indians thousands of years ago.

MilNeil put up some photos and commentary about the site in his blog, vigorousnorth.com, on which he catalogs non-urban wildlife, activities and settings in and around Portland. Based on old maps, he speculated that the Hammond Street site, now hundreds of yards from Back Cove, was once on the shoreline and a logical place for native Americans to harvest and eat shellfish.

It turns out MilNeil was off, but only by a few yards.

Arthur Spiess, the senior archaeologist of the Maine Historical Preservation Commission, said the Hammond Street site was on the coastline, but on the “subtidal” part, meaning under water.

Spiess said a whole section of the cove was filled in over the years, mostly in the 1800s. The dirt containing the shells also includes marine clay, suggesting that it was dug up in huge scoops and transported to Hammond Street and other parts of Bayside as fill to allow development.

“It’s not an intact site or a burial ground and maybe not even a midden,” Spiess said, noting that the fill could have been taken from parts of the cove that contained natural oyster and clam beds.

Spiess said a University of Southern Maine archaeologist planned to look at the site — if he can make it before contractors finish the foundation for the apartment house that’s going up there — to see if it is possible to find where the fill came from and if it was indeed a midden. Some other artifacts, such as broken shards of pottery, would likely suggest a midden as opposed to a natural layers of shells, he said.

MilNeil said he wasn’t particularly disappointed or surprised that state officials were skeptical that he had stumbled on a midden.

He said a blog reader from New Zealand, where middens are apparently more common, also said MilNeil’s photographs suggest fill rather than an archaeological site. Middens, the reader said, wouldn’t necessarily have been laid down in layers, separated by feet of marine clay and dirt.

MilNeil said he is still excited about the find because it is evidence of how humans have changed the landscape in Portland.

“I’m really excited by the fact that this site is now well away from the ocean and once it was coastline,” he said.

Staff Writer Edward D. Murphy can be contacted at 791-6465 or at:

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