Colo. Study Points to Health Impacts from Gas Drilling

Charleston Gazette
19 March 2012
By Ken Ward Jr.

An important new study from the University of Colorado’s School of Public Health raises questions about potential public health impacts of the natural gas drilling boom in West Virginia and across the country. Here’s what the news release from the school says:

In a new study, researchers from the Colorado School of Public Health have shown that air pollution caused by hydraulic fracturing or fracking may contribute to acute and chronic health problems for those living near natural gas drilling sites.

“Our data show that it is important to include air pollution in the national dialogue on natural gas development that has focused largely on water exposures to hydraulic fracturing,” said Lisa McKenzie, Ph.D., MPH, lead author of the study and research associate at the Colorado School of Public Health.

There are media reports out about the study in the Denver Post and on the website of Colorado Energy News.

According to the news release:

The report, based on three years of monitoring, found a number of potentially toxic petroleum hydrocarbons in the air near the wells including benzene, ethylbenzene, toluene and xylene. Benzene has been identified by the Environmental Protection Agency as a known carcinogen. Other chemicals included heptane, octane and diethylbenzene but information on their toxicity is limited.

The report, which looked at those living about a half-mile from the wells, comes in response to the rapid expansion of natural gas development in rural Garfield County, in western Colorado.

Typically, wells are developed in stages that include drilling followed by hydraulic fracturing , the high powered injection of water and chemicals into the drilled area to release the gas. After that, there is flowback or the return of fracking and geologic fluids, hydrocarbons and natural gas to the surface. The gas is then collected and sold.

Garfield County asked the Colorado School of Public Health to assess the potential health impacts of these wells on the community of Battlement Mesa with a population of about 5,000.

The study is due out soon in the journal Science of the Total Environment, and here’s the abstract:

Residents living ≤ ½ mile from wells are at greater risk for health effects from NGD than are residents living > ½ mile from wells. Subchronic exposures to air pollutants during well completion activities present the greatest potential for health effects.   The subchronic non-cancer hazard index (HI) of 5 for residents ≤ ½ mile from wells was driven primarily by exposure to trimethylbenzenes, xylenes, and aliphatic hydrocarbons.  Chronic HIs were 1 and 0.4. for residents ≤ ½ mile from wells and > ½ mile from wells, respectively.  Cumulative cancer risks were 10 in a million and 6 in a million for residents living  ≤ ½ mile and > ½ mile from wells, respectively, with benzene as the major contributor to the risk.

Keep in mind that the new natural gas drilling law championed by Gov. Earl Ray Tomblin allows drilling in West Virginia within 625 feet of occupied residences, well within the 1/2-mile (2640 feet) distance cited in the study as the area where residents would face greater health risks.