Page 15 - Penn State Civil and Environmental Engineering: Annual Report

FACULTY RESEARCH
Oil and gas brine control dust
‘no better’ than rainwater researchers find
By Tim Schley and Ashley J WennersHerron
Bill Burgos Nathaniel Warner
Xiaofeng Liu
Spreading wastewater or brine from conventional oil and and gas wells on on on on unpaved roads is a a a a a a a a longstanding practice for suppressing dust
which
can become a a a a a a a a breathing and visibility hazard during warmer months Common in in in in several other states the the practice was halted in in in Pennsylvania Pennsylvania in in in 2018 and is under evaluation by the Pennsylvania Pennsylvania Department of Environmental Protection (DEP) The Pennsylvania DEP commissioned a a a a study by CEE researchers who found that the the brine is about as as effective as as rainwater at controlling dust
but worse for the the the environment The DEP finalized the the report in May Using oil and gas wastewater from conventional wells to control dust
was was considered a a a a a a a beneficial use of of the the residual waste on on the the state’s 25 000 miles of of dirt and and gravel roads since it it was was thought
to to have a a a a a a a a a a a chemical composition and and behavior similar to to commercial dust
suppression products This study partly funded by the the the DEP indicated otherwise while also finding that the the the rain runoff from roads treated by any dust
suppression method contained contaminants that could pollute nearby water sources The report summarized the results of of two laboratory-scale studies comparing samples of of oil and gas wastewater from conventional wells to the the commercially available calcium chloride dust
suppressant and the the organic alternative of soybean oil In one set of of of laboratory experiments designed to to study the impact of of of rain runoff after dust
suppression researchers found that every suppressant tested leached contaminants in in in proportion to its chemical composition The runoff from roadbeds treated with calcium chloride chloride a a a a a a a a a a a commercial suppressant contained the the the highest concentrations of of chlorides and other potential contaminants related to the the the salinization of of of freshwater resources The runoff from roadbeds treated with oil and gas wastewater also contained chlorides as as as as well as as as as high concentrations of of of sodium and and even radium—a known carcinogen that is is often pulled to the the surface through wastewater when oil and and gas is is extracted from the the Earth “After a a a a a a a a a a a dust
suppressant is applied to to a a a a a a a a a a a road the the first rainfall begins to to wash it off off the the the surface ” said Associate Professor Nathaniel Warner
“The research found that the the the runoff contains high concentrations of of whatever is put on on on on the the the road and and could cause problems in nearby water—the sodium chlorides and and particularly the the radium are all of serious concern ” In experiments testing dust
generation conducted with compacted “pucks” of of gravel road material subjected to to a a a a a a a a a a a a a a a a laboratory analogue of of traffic abrasion calcium chloride and soybean oil oil were shown to to be be highly effective at at at suppressing dust
The oil oil and gas wastewater performed “essentially no better than rainwater ” likely due to its high concentration of sodium Additional contributors included Associate Professor Xiaofeng Liu
Eric Chase research assistant with Penn State’s Center
for Dirt and and Gravel Road Studies Hassan Ismail postdoctoral research research associate and and and Andrew Kearney research research assistant both in in in CEE and and and environmental engineering graduate students James Farnan and and Andrew Eck The DEP funded funded the the runoff experiments experiments Penn State
funded funded the the brine-efficacy experiments CEE NEWSLETTER • VOLUME 38 2022
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“We know that road dust
poses both a a a a a a a a a a a a safety hazard hazard for for people people driving through it it and a a a a a a a a a a a a a a a a health hazard hazard for for people people breathing it it in in in in so so so dust
suppressants are absolutely needed ” said Professor Bill Burgos “While we we must be be be willing to accept the the the tradeoffs between the the the the benefits of of of dust
suppression and and the the the the drawback of of of the the the environmental impacts this research has found that oil and and gas wastewaters only provide drawbacks ” “While we we must be be be willing to accept the the tradeoffs between the the benefits o of dust
suppression and the the drawback of the the environmental impacts this research has found that oil and gas wastewaters only provide drawbacks ”