Harford County's zoning hearing examiners will meet Tuesday to determine the dates for public hearings on a request by Arundel Sand & Gravel Co. for a zoning change at its big quarry off Interstate 95 near Havre de Grace.
The company needs zoning approval before it can move two large piles of overburden -- dirt from mining operations -- from one part of its property and combine them into one mound at another part of the quarry.
The shift of about 8 million cubic yards of overburden is needed to allow mining of stone beneath the piles.
Rock mined from the quarry, on the western bank of the Susquehanna River, is used for roads and driveways throughout Maryland and other East Coast states.
The proposed shift in the mining operations has stirred community opposition. Residents living near the quarry complained to the Maryland Department of the Environment in May that shifting mining operations closer to homes poses a health threat.
Benedict Schwartz, a vice president of the River Hill community association, said the company's rock-crushing operation creates silica dust and that "respirable crystalline silica is a toxin and a Class 1 carcinogen, known to cause lung cancer, asthma, kidney disease and other respiratory diseases."
In May, nine of the 10 members of the Harford County legislative delegation signed a letter asking the Maryland Department of the Environment to look into the possible health hazards to area residents from the proposed change in Arundel Sand & Gravel's mining operations.
In a separate letter, Republican state Sen. Nancy Jacobs wrote: "The Maryland Department of the Environment should sign off on this site modification, if and only if it can guarantee that the air quality and consequently the health of the neighborhood residents will not be negatively affected."
Responding to the delegation's letter, MDE Secretary Kendl P. Philbrick wrote: "The increase in emissions of silica or crystalline silica as a result of the proposed relocation of overburden will be minimal.
"The primary source of silica and/or crystalline silica from the quarry operations is the crushing, blasting, drilling and other abrasive activities that occur in the process of handling of rock. The proposed permit modification will not change the quantity of rock that will be crushed and handled at the quarry."
He said the impact of relocating overburden would be similar to that at a construction site where soil is graded, stockpiled or removed. The company, he said, is required to take steps to prevent dust from becoming airborne and a nuisance to the local residents.
Philbrick said the department is aware of public concern regarding the quarry operation and will conduct a thorough review of all data before making a final decision.
Del. Barry Glassman, chairman of the county's legislative delegation, said he received Philbrick's letter Tuesday.
During a meeting with MDE officials last week, Glassman said he was told that the state would not approve the company's request for a modification of its mining permit until it obtained the needed zoning approval from the county.
Glassman said he plans to introduce a bill during the next legislative session that would prohibit the state from approving such projects until they have county approval.
The county's director of planning and zoning, J. Steven Kaii-Ziegler, has expressed concern in the past about Arundel Sand & Gravel's plan, saying the height of the 520-foot stockpile would need to be reduced and that it needs to be farther from homes in that area.