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Statement from Seth Kovnat, Structural Engineer

Sunoco Logistics proposes to build a massive high pressure NGL line in unsafe proximity to our homes, schools, businesses, and care facilities- across 350 miles of Pennsylvania, and right through the heart of densely populated Delaware County.  The proposed Mariner East 2 project, a 20 and a 16 inch diameter pipe operating at up to 1,500 pounds per square inch of pressure, would transfer “natural gas liquids” from western Pennsylvania to Sunoco’s Marcus Hook facility for export.


Safety must outweigh all else when considering any project that potentially puts the public at risk. Sunoco’s proposed Mariner East 2 is both dangerous and unnecessary for Pennsylvania. My comments are based on my background as an aerospace engineer with extensive experience with piping. As the propulsion tubing lead for NASA’s Orion program and many R&D aircraft, I am no stranger to piping hazardous material under pressure.


It is clear that the majority of the public, including vital decision makers, have not had a full understanding of the risks associated with the transport of NGLs under enormous pressure. These highly volatile materials (ethane, butane and propane) are not “natural gas,” nor are they liquid at ordinary temperature and pressure. And they have a deadly combination of properties. If released from the pipeline, they will expand about 500 times in volume as they transform from liquid to gaseous state. That gas is colorless, odorless, toxic, heavier than air, and extremely flammable or explosive. Something as ordinary as starting a car, using a cell phone, or ringing a doorbell could serve as an ignition source for a gas cloud which you may not be able to detect.


Even a small leak of these materials has the potential to be catastrophic, and a large leak could cause a regional disaster.  Sunoco’s safety record must be considered when assessing the probability of such a leak happening.


Sunoco Pipeline and its predecessor, Sunoco Inc., have between them reported 299 leaks of hazardous liquids since 2006 alone, more than any other operator tracked by the federal government. That’s about two leaks per month on average, every month for a decade. In May 2016 Sunoco reported a leak of a toxic, highly volatile liquid in Aston, near Sun Valley high school.  Sunoco’s own report confirms the gas reached a “high consequence area”, meaning it moved beyond the bounds of the Twin Oaks facility. Edgmont Township residents have experienced two large hazardous liquids leaks from Sunoco pipelines in recent memory. After the last one, discovered in 2015 by the property owner, a gasoline additive manufactured by Sunoco continues to be detected in nearby wells.


Around 25% of the time Sunoco’s systems fail to detect a leak. But suspend disbelief for a moment and imagine a scenario where a leak is identified and valves shut off immediately. There are still over 500,000 gallons of highly volatile liquid in a typical six mile long pipeline segment. As the liquid escapes the pipeline, it changes from liquid to gas at cryogenic temperatures. The carbon steel that is the industry standard for pipelines becomes brittle and glasslike. This alone can turn a small leak into a cataclysmic rupture.


The liquid product would then expand to 300 million gallons of heavier-than-air-gas, hanging low to the ground, about the height of the children that congregate at Glenwood Elementary School and Sleighton Park. One spark to the over 2.5 million pounds of propane, ethane, or butane gas and the entire gas cloud will ignite explosively, creating a 3,600 degree fire blanket with energy equivalent to the “Little Boy” nuclear weapon dropped over Hiroshima.  


Sunoco’s generic emergency protocol suggests that in the event of a known or suspected leak, residents should quickly move away from the pipeline on foot (cars could ignite the gas), upwind, to a distance of at least one-half mile. Assume for a moment that everyone within a half-mile of a pipeline knows the wind direction at all times- what if you are elderly, or very young, or just cannot sprint a half-mile at a moment’s notice? Consider evacuating across rugged terrain, over fences, around buildings, through woods, perhaps at night or in cold or inclement weather? Neither Sunoco, nor any other agency has done area-specific planning to safely evacuate schools or hospitals or elder care facilities in our densely populated, high consequence area. This lack of emergency preparedness is shockingly unacceptable.


The proposed Mariner East 2 pipeline is a completely unnecessary safety and health risk to the residents, businesses, and schools of Delaware County. It is unlike anything currently operating in our densely populated area. Its sole purpose: to improve the bottom line of Texas-based Sunoco by shipping materials overseas. If this pipeline is constructed, our community will be left with a ticking time bomb running under our feet, jeopardizing our property values, safety, and quality of life.


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