USA: Burying 38,000 m3 of pyritic rock

PenDOtt Route 2001 project

State Route 2001, in Pike County, Pennsylvania, is undergoing considerable improvements. Back in March 2014, the Pocono Record (08.03.14) reported that a major phase of the improvement in Lehman Township was delayed due to the identification of pyritic rock along the route alignment. Quoting from the article:

“Bore samples taken two years ago for this project did not initially reveal a pyrite problem, but recent borings did show it in various places along the entire project area, which runs from where the last phase ended at Little Egypt Road to Oakridge Road.”

In July 2014, PyriteProblem.com reported on how engineers from the Pennsylvania Department of Transportation (PennDOT) were attempting to determine how much pyrite was present and how to mitigate the problem. Click here to read the post. It was later estimated that the road project would be delayed by a least one year as a result of the pyrite discovery (Pocono Record, 13.03.14).

Disposal of the pyritic rock material

In March 2016, the Pocono Record (27.03.16) reported that PennDOT wanted to transport the pyritic rock waste material to Blooming Grove Township, “…at a site already under preparation at the intersection of Interstate 84 West and from the Exit 30 off-ramp to Route 402.

It was reported (Pocono Record, 14.04.16) that the pyritic rock material would be treated with lime prior to encapsulation (burial) and later planting, with monitoring for perhaps three to five years. In addition, it was reported that PennDOT, the Department of Environmental Protection and the Pike County Conservation District had considered eighteen sites for encapsulation of the pyritic material, but that “..the Exit 30 site was the only one large and flat enough and without wetlands or thick woods..” The proposals were met with much public opposition.

Previous pyrite problems in Pennsylvania

A number of problems have occurred relating to pyrite in Pennsylvania:

  • Pyrite discovered during Marshall Creek Bypass construction, project curtailed (2004)
  • Pyrite discovered during construction of Interstate 99 in State College, major leaching problems (early 2000s)
  • Pyrite oxidation has also been the cause of various other problems across Pennsylvania, including structural damage to homes (see Engineering News Record 1960, Spanovich 1968, Dougherty and Barsotti 1971, Hoover et al., 2004 Parfitt et al., 2011).
  • See the D’Appolonia website for a succinct PDF information sheet on damages to a School as a result of heave of pyritic shale.
Share Button