In a comment thread in a recent NJ.com article (Opponents take issue with PennEast pipeline environmental report), a little mini-discussion occurred in the comment threads that I’d like to highlight. A poster was listing issues they had with natural gas pipelines, and one of them was:
any spill or overdevelopment will destroy the purity of water for millions of new jersey residents
A person named “Commentator73” took issue with this, and replied:
A “spill” of natural gas? Natural gas is not gasoline, it is a gas which is not toxic and is lighter than air. If there ever is a leak, the gas will simply rise and dissipate in the atmosphere leaving absolutely zero residue. No cleanup needed and the water complelely unaffected.
We’ll leave aside Commentator73’s long history of cheerleading for PennEast for another time. But I do want to address this myth they’re propagating here. Yes, it’s true that natural gas is not the same as other pipelines carrying “liquids”. But that doesn’t make them risk free. Let’s set the record straight by answering Commentator73 directly.
The Cost of the Pipeline 
@Commentator73 You’re right, natural gas is not gasoline (or oil or other liquids).
Otherwise your explanation glosses over some particulars that are a bit important. If there’s a leak, that leak could ignite. You then have a 1480 pound per square inch fueled blow torch igniting several thousand square feet around the breach. This is not theoretical – the recent natural gas pipeline explosion near Pittsburgh involved a house burning down and a man being burned over half his body. Other incidents in San Bernadino, CA, Arlington Virginia, and elsewhere have been even worse.
You gloss over how pipelines change mobilization of chemicals in the soil due to the electric charge maintained on the pipeline, and the materials used to construct it. Some very nasty things like arsenic can mobilize along the pipeline due to this. And yes Virginia, arsenic in your drinking water is a very, very bad thing.
You gloss over geological and top cover changes created by the pipeline. In most of Hunterdon County there’s bedrock right at the surface, and a whole lot of tress as top cover. These serve to protect us against significant erosion, limit sedimentation in streams, keep water clean and charging into our parched aquifers, and prevent flash flooding and similar problems.
When the pipeline is built, they’re be blasting the bedrock away down to a depth of 7′-9′. All trees and significant shrubs will be clear cut on a 100′-125′ right of way, and a 50′ right of way will be maintained after that. So bedrock will be replaced with simple earth, the trees and their vital roots will be gone, and a great deal of this will be done on very steep slopes – slopes that feed down into the valleys that contain our C1 streams. Expect significant erosion, sedimentation of our streams, increased problems with flash flooding, plus all of the environmental issues from creating open breaks in tree cover.
You forget about contaminants in natural gas pipelines. It is far from “pure”. Liquid condensates build up in the pipeline. Radon is a constant issue, particular in our region. Other contaminants come along for the ride as well. You may have heard of “pigs” used to clean the pipelines. This is why they’re there – the gas is far from pure and the pipeline needs very regular cleaning.