Morning Call: August 12, 2004

Three quarry operators in the Nazareth area have begun drilling wells outside their property lines as part of a task force of state and federal agencies to help determine what has caused a rash of sinkholes in parts of Northampton County.

But now, part of the task force -- announced six months ago -- no longer is actively participating in the investigation. The U.S. Army Corps of Engineers is dropping out for now because it does not have the funding to help in the investigation, said Bill Mueller, the Corps' strategic planner in Philadelphia.

"The biggest problem we have right now is funding," Mueller said. "Congress appropriated $18 million nationwide [to the Corps], and there's no more money. I don't know about next year's budget. It's looking a little better, but not much better."

Ron Young, spokesman for the state Department of Transportation, said all the state agencies are pursuing the probe, including PennDOT, the Department of Environmental Protection, Department of Community and Economic Development, and Bureau of Topographical and Geological Survey.

DEP spokesman Karl Lasher said he could not comment on the Corps situation, but "we are still actively part of this process."

Mueller said the Philadelphia office, which covers the Lehigh Valley, has to prioritize its spending, putting money toward projects that are under or close to construction. He said the Corps has just enough money to put in gauging devices in Bushkill Creek to measure stream flow, and not enough to investigate the sinkholes in and around the creek.

"We are not being arbitrary," Mueller added. "This is how we slice up an inadequate pie. Sometimes I wonder about the Corps, but this makes sense."

The task force was announced Feb. 5 at a meeting in Nazareth led by PennDOT Secretary Allen Biehler, who was addressing residents' concerns about the northbound Route 33 bridge that partially sank into a sinkhole on the creek bank on Jan. 24. The task force, however, took more than two months to get off the ground because the agencies were hampered by departmental regulations and mandates.

Since then, the agencies have worked more closely. And PennDOT rebuilt the northbound bridge ahead of schedule and is dismantling and reconstructing the adjacent southbound bridge to prevent a similar sinkhole-forced closure from occuring.

Sinkholes form naturally in porous limestone regions, but can be accelerated by mining, development and leaky water pipes.

"Finally they are being proactive instead of reactive," said Linda Iudicello, a member of the Brookwood Group, a homeowners association that formed shortly after the sinkholes began opening in their Palmer Township neighborhood in 1999. "If [the wells] help us determine what is creating the problem, then we've got a better chance of getting a fix, or a Band-Aid on it, because I don't think you'll ever fully fix the problem," she said.

Lasher said two of the six planned wells have been completed since July 19, and the rest should be drilled within the next two weeks. Hercules Cement Co. of Stockertown -- which completed a well on Bushkill Street in Stockertown, about 80 yards from the Stockertown-Tatamy bridge that was damaged by sinkholes in 2000 -- will drill three, Lasher said. Essroc Italcementi Group of Upper Nazareth and Eastern Industries Inc. each will drill one, and Northampton County another in Tatamy, he said.

"All are south or southeast of Hercules' quarry," Lasher said.

Unlike Lehigh County, Northampton County never has monitored or recorded groundwater levels, with the exception of one well near Jacobsburg State Park that monitors drought conditions, according to the DEP. The quarries have monitored groundwater levels since the 1970s, but with no historic data, officials do not know how the quarries have affected the groundwater table when they began operating in the early 1900s.

When a quarry or mine goes deep enough, it eventually will hit the groundwater table, causing water to flow into the pit. To keep the operation dry, a quarry must pump out the groundwater and discharge it someplace else, usually into a stream. The pumping process, which works like a household well, creates a funnel effect in the underground that is called the "cone of depression" or "zone of influence."

Studies have shown that depending on its size, a quarry's cone can cause sinkholes by sucking groundwater for miles. That undermines the limestone, clay filling and soil above where the groundwater had been until the surface buckles and eventually collapses, creating a hole.

Residents have blamed the quarries -- particularly Hercules because it is suspected of having the largest cone -- for causing or exasperating the sinkholes. And, although the DEP has forced Hercules and the other plants to repair sinkholes outside their property line since 2000, officials have not blamed the quarries for causing all the sinkholes.

Steve Esack