Beneath the Surface

The United States holds enough oil and gas to power the country for hundreds of years, and Colorado is at the center of the search for energy resources. Using a controversial process called hydraulic fracturing—better known as fracking—and new drilling techniques, oil and gas companies are able to extract these previously inaccessible fossil fuels. These technologies may be the biggest step yet toward securing our energy independence. But at what cost?

December 2012

[ The research


Recent studies specific to Colorado and the West suggest significant environmental side effects that could pose health risks to people living in proximity to oil and gas operations.
But, in the words of COGCC director Matt Lepore (see page 95), “there’s no such thing as a perfect study.”


The researchers: National Oceanic
and Atmospheric Administration (NOAA)

What they studied: Greenhouse gas emissions
from natural gas drilling in northeastern Colorado/Weld County. 

What they found: Natural gas extraction leaks twice as much methane—about four percent of the total extracted—into the atmosphere as previously estimated by the EPA. Methane, the primary component of natural gas, is 20 times more potent than carbon dioxide over 100 years. Other emissions, including the carcinogen benzene, are also likely being leaked at higher-than-expected rates.

Why it matters: Although natural gas may burn cleaner, the effect is diminished if methane and other toxins are escaping into the atmosphere during its extraction and processing.  

The caveat: Most of the data were collected in 2008. Since that time, Colorado has imposed stricter air emissions rules: 84 percent of wells that have been hydraulically fractured since April 2012 have undergone “green completions” to reduce the amount of methane leaked. This is a new EPA rule that will take effect nationally by 2015 and is expected to save the industry $11 million to $19 million that year in natural gas previously “lost” to the atmosphere. 


The researchers: Colorado School of Public Health, University of Colorado

What they studied: Health impacts from exposure to natural gas development in Garfield County. 

What they found: People living closer to natural gas wells are at a greater risk for developing neurological and respiratory diseases than those who live farther away. “This hazard is greatest during the period of short-term, high emission that occurs during well completion,” says research associate Dr. Lisa McKenzie. The same is true for cancer odds, primarily due to benzene exposure: 10 in a million for residents near wells; six in a million otherwise.

Why it matters: Further refined data like this could be helpful for setback rules (the minimum distance from a building that an operator can drill).

The caveat: The EPA’s default methodology used here is designed to overestimate risks. And data were collected between 2008 and 2010 during uncontrolled flowback, meaning there was no technology to curb leaked emissions, so results may be inconsistent with how other wells operate today.


The researchers: Environmental Protection Agency (EPA)

What they studied: Groundwater contamination from natural gas fracking near Pavillion, Wyoming. 

What they found: Hydraulic fracturing is linked to contamination of groundwater. In two wells, chemicals were present in amounts higher than the EPA’s drinking water standard. 

Why it matters: Hydraulic fracturing was exempt from the EPA’s Safe Drinking Water Act. At the time, the industry claimed that groundwater contamination from fracking had never been proven. 

The caveat: The U.S. Geological Survey, when called upon for additional sampling, claimed the EPA’s methodology was flawed and inconsistent with its own. The EPA has defended its findings.


Getting Dirty

Three ways fracking could contaminate drinking water. 

1. Surface Spill

Someone handling fracking fluid could spill that fluid, which could then seep into the ground or leak into a stream or river. It’s also possible that fracking fluid could leak from a faulty storage tank or truck while it’s being transported. There have been a total of 1,658 reported spills in Colorado since 2009.

2. Well Casing 

Companies use millions of pounds of steel and cement to reinforce the part of the well that passes through freshwater sources. If the encasement is not properly constructed or fails, fracking fluid could leak into an aquifer. 

3. Migration

The cracks created in shale rock during the fracking process could extend farther than anyone realizes, thus creating an underground pathway for fracking fluid or natural gas to travel up into an aquifer. This migration is still largely a theory.