The property for which Mellott wants the zoning change is 80.33 acres in an agriculture zone, on the east side of Mapleville Road (Md. 66) and north of the Interstate 70 intersection.
Mellott has requested that an industrial mineral floating zone be placed over the agriculture zone. That would allow the company to increase the volume of mineral extraction, Mellott Vice Chairman Terry Randall said during a November public hearing.
Many residents and several expert witnesses have said a quarry expansion could have negative effects on surrounding property, including causing more sinkholes from blasting near already porous grounds, increasing traffic and disrupting a peaceful and historic area.
The Washington County Historical Trust and the Maryland Historical Trust said the area to be mined used to be that of Mount Aetna Furnace, which made cannons during the American Revolution.
The preservation groups said historic artifacts probably are still buried in the ground.
"The archaeological remains hold great potential for revealing much about cannon casting technology in the American Colonies," according to testimony submitted to the county by residents. "With proper investigation, the archaeological remains will also provide insight into 18th-century industrial processes and development."
Mellott's lawyer, John H. Urner, argued in written testimony that no "meaningful documentation" exists that such artifacts remain on the property.
He wrote that development in the area has probably already destroyed the artifacts.
"Why the state has made no effort over the last 30 years to protect the Mount Aetna furnace is a mystery," according to the testimony. "But the result is clear. Residential and other land use on the north side of Mount Aetna Road and on the south side of the Mellott property has destroyed much of what is known to have existed."