USA

Pyrrhotite disaster in the northeastern United States – CCACB Guest Post

Pyrrhotite disaster in the northeastern United States

The following article is a guest post by the Connecticut Coalition Against Crumbling Basements on the pyrrhotite disaster in the northeastern United States.

In New England in the United States, homes are crumbling from pyrrhotite. Nearly twenty towns in northeastern Connecticut are affected, as well as towns across the border in neighboring Massachusetts. The scope of the problem is unknown, but after a state investigation, a single quarry within a driving radius of these homes is believed to be the culprit.

Homes with visible damage were built between the early 1980s and 2003; however, this quarry has been used for building projects up until early summer 2016 when the quarry owners agreed to cease pouring residential properties for one year.… Read the rest

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.… Read the rest

Research Paper: Modelling pyritic shale expansion

Pyritic Shale Expansion

Shad Hoover, Whitney Greenawalt and Brian Tittmann (all of CMT Laboratories Inc, State College, PA, USA) have published a paper on the measurement of pyritic shale expansion due to the oxidation of pyrite. The authors use laboratory oxidation experiments and theoretical geochemical models to estimate expansion rates and magnitudes.

The paper is titled “Experimental and Theoretical Modeling of Expansion in Pyritic Shale”.

Abstract

“Expansive pyritic shales are found in black carbonaceous shales throughout the United States as well as in other countries, including Ireland, England, Norway, Canada, and Sweden. Expansion occurs when the pyrite, which occurs either as finely disseminated syngenetic framboids, macroscopic crystals, or diagenetic replacement fossils, oxidizes to form sulfuric acid.
Read the rest

Where to bury 38,000 m3 of pyritic rock?

PenDOtt Route 2001 project

State Route 2001 is a 35 km road in Pike County, Pennsylvania, which is undergoing considerable improvements. The Pocono Record (08.03.14) reported that the next major phase of the improvement (Lehman Township) was due to start in March this year but 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.”

Dealing with the pyritic rock

According to the Pocono Record (08.03.14), engineers from the Pennsylvania Department of Transportation (PennDOT) are now attempting to determine how much pyrite is present and how to mitigate the problem.… Read the rest