Posted on Fri, Jul. 08, 2005 Acid rock found at new locationBy...

Posted on Fri, Jul. 08, 2005





Acid rock found at new location

By Mike Joseph

[email protected]


Road builders and environmental regulators said Thursday they have discovered yet another place where acid-producing rocks excavated from an Interstate 99 site at Skytop were used as road construction fill.

Nearly a million cubic yards of pyritic rocks were unearthed from late 2002 to late 2003 during construction of the highway because of what the state Department of Transportation has called a lack of "vigilance." The discovery of a new location under a private driveway comes as the problem of how to clean up Skytop enters its 22nd month of study.

The driveway fill is 1,000 feet long, 12 feet wide and two to four feet deep -- a private lane called Arbo Mountain Lane off state Route 550. The asphalt paved driveway, built in October 2002 at the start of construction, climbs the Skytop Mountain foothills to the home of Todd Arbogast.

The property is adjacent to the I-99 construction site at Skytop and is the subject of other ongoing issues between the owner and the state. PennDOT wants to drill a monitoring well through another part of the private property and said Arbogast won't allow it for fear of damage to his well-water supply.

When state officials drove to Arbogast's home to discuss the monitoring well issue, they said, they noticed red iron stains -- one of the telltale signs that the exposed iron pyrite, reacting with oxygen and water, has been forming metal-dissolving sulfuric acid.

Gary Byron, Department of Environmental Protection assistant regional director, said Thursday that his agency considers information from that monitoring well "critical" to the decision-making process.

Byron said cleaning up the acidic rocks under the driveway will be incorporated into the state's final remediation plan. "It's got to be removed," he said.

Arbogast acknowledged that his property is involved in the ongoing cleanup issues at Skytop but otherwise did not comment.

Also Thursday, Byron said the million-dollar tests of the cleanup product Bauxsol probably will not begin until August, as DEP is still awaiting a plan that shows specific locations where Bauxsol manufacturer Virotec plans to drill holes and inject solutions of the product into the acidic spoil piles and fill areas.

PennDOT is hoping Bauxsol can be injected into the piles of pyrite-laced rock and neutralize the acidic runoff, giving it an alternative to removing some or all of the rock from the site.

Byron said up to 9 million gallons of water -- up to 100,000 gallons a day for 90 days -- will be used to create the Bauxsol slurries. He said DEP is still deciding from where to draw the water. An I-99 construction well used to make concrete is one possibility.

DEP hydrogeologist Randy Farmerie said residential wells in the Skytop foothills continue to show "consistent" levels of sulfates, or sulfuric acid salts, the key measure of heavy metal contaminant levels in water.

Farmerie said there's a "small set" of wells with elevated levels that indicate pyrite is being oxidized, but not since last October has any home well shown sulfate levels that are excessive.

Mike Joseph can be reached at 235-3910.