Expert Geologist Report

The report, authored by Dr. H.C. Clark, argues that the proposed natural gas storage in Gallery 2 is unsafe due to significant geological instabilities, including a history of massive roof collapses and the presence of major fault systems. Dr. Clark contends that the Federal Energy Regulatory Commission (FERC) and Arlington Storage Company have ignored critical historical data and failed to provide adequate geomechanical modeling or monitoring plans to address these site-specific risks.

• The Gallery 2 caverns are not new, optimally engineered facilities but are over half a century old, having been used for brine mining and liquid petroleum gas (LPG) storage before being plugged and abandoned for decades.
• A massive roof collapse occurred in Cavern 30 during the 1960s, where a fault block estimated to weigh more than 400,000 tons fell from the roof to the floor.
• The site is characterized by complex faulting, including a bedding plane thrust fault that enabled the hydraulic fracturing connection between Caverns 30 and 31, and the Jacoby-Dellwig Fault, a major strike-slip tear fault that has previously acted as a conduit for brine to flow to the surface.
• Arlington Storage Company explicitly denied any history of cavern roof failures in the Watkins Glen Brine Field, contradicting documented evidence of the 400,000-ton collapse in Cavern 30.
• The report criticizes the FERC Environmental Assessment (EA) for being too brief and failing to address specific concerns regarding thrust faulting, the roof collapse event, and the necessity of a sensitive seismic network for monitoring.
• Current geomechanical modeling by Arlington is deemed unreliable because it has not been validated against the known historical roof failure of Cavern 30.
• The report identifies significant gaps in Arlington's responses to FERC's engineering requests, specifically regarding the size and volume of rubble piles and the width of the connection between caverns.
• Proposed monitoring plans are insufficient; the report recommends frequent sonar surveys, improved subsidence monuments, borehole microseismic recording, and soil gas surveys, noting that Arlington's internal reports suggest no further sonars are planned once gas storage begins.

APA

Clark, H. (2014). Expert Geologist Report. Earthjustice. https://earthjustice.org/wp-content/uploads/seneca_lake_geology_review.pdf

Chicago

Clark, H.C. Expert Geologist Report. Earthjustice, 2014. https://earthjustice.org/wp-content/uploads/seneca_lake_geology_review.pdf.

Wikipedia

{{cite report |last1=Clark |first1=H.C. |title=Expert Geologist Report |publisher=Earthjustice |date=15 January 2014 |url=https://earthjustice.org/wp-content/uploads/seneca_lake_geology_review.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{clark2014expert, author = {Clark, H.C.}, title = {{Expert Geologist Report}}, institution = {Earthjustice}, year = {2014}, month = jan, url = {https://earthjustice.org/wp-content/uploads/seneca_lake_geology_review.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }