Thoroughbred horses walk across grazing land on a farm in Weld County south of La Salle, Colo., on March 22, 2014.

A 2012 study conducted by the Colorado School of Public Health found that people living within a half-mile of oil and gas wells were at a greater risk for chronic health problems due to air pollution from fracturing and well completion activities. The study examined air quality near oil and gas operations in Garfield County, which has the second-highest number of oil and gas wells in Colorado—in excess of 10,500.

Researchers found 45 chemicals that could negatively affect human health in the air samples, including BTEX compounds and methylene chloride, which had not previously been disclosed as a component of or emission from drilling operations.  The levels of these chemicals did not exceed safety standards, but were found in high enough concentrations that an area with more dense drilling operations—such as Weld County—might exceed such standards. Researchers also raised the question of whether the current air quality standards are strict enough to mitigate the potential health effects of these compounds.

“That study was based on voter complaints that people had, so that was based on real people who had called and reported to the COGCC that they were smelling odors coming off a well pad during well completion,” said Lisa McKenzie, an associate researcher at the University of Colorado Boulder and lead author of the study, “and they lived about a half a mile from the well pads, so for that data they’re smelling odors, and they may have some exposure.”

Industry professionals and supporters criticized the study because the researchers did not have full access to the pad site, so the air samples were collected from a nearby location.

A follow-up study published in 2014 indicated that women who live within 10 miles of oil and gas wells—particularly areas with high well density—were 30 percent more likely to have children born with certain congenital heart defects than those who did not live near wells. The study examined babies born between 1996 and 2009 across Colorado.


“I feel that there are all sorts of sides to this issue, and I feel that every side has exploited our research to their advantage.” – Lisa McKenzie, associate researcher at the University of Colorado Boulder


“From the first study, we saw that one of the non-cancer potential health effects for that chronic exposure were developmental effects and we also saw that concentrations of benzene, toluenes and xylenes were higher in the air samples collected closest to the well pads,” McKenzie said. “Those three chemicals are known to cause birth defects and mutate cells, so we then decided that we could look and see if we could see increases in these birth defects.”

“We looked at congenital heart defects as a whole, so that’s where we saw a 30 percent higher increase in congenital heart defects in the highest exposed area compared to women with no wells around them,” she said. “Then we looked at specific congenital heart defects and we saw that 3 or 4 of them were also elevated in that highest-exposed group.”

Oil and gas proponents and state officials, including Chief Medical Officer Larry Wolk, criticized that study as well, saying it did not analyze the possibility of other contributing factors and that it was biased in favor of environmental activists. But McKenzie said both environmental advocates and oil and gas advocates have capitalized on the research.

“I feel that there are all sorts of sides to this issue, and I feel that every side has exploited our research to their advantage,” McKenzie said. “I don’t believe that environmentalists have exploited it any more than the industry has.”

McKenzie’s study on birth effects contributed to what Ed Graham called a “panic attack” when he learned about it.

“My kids were conceived in this house, and within 10 miles of my house is—I don’t know, I would guess 5,000 wells,” Graham said. “I’m thinking, hopefully my kids are okay.”

Graham has submitted multiple complaints and requests to the COGCC asking for an air quality emissions test, but no tests have been conducted thus far. He emails COGCC inspectors videos of emissions and loud noises from the plants whenever the levels become unbearable—which often occurs on a daily basis.

In addition, oil and gas operations surround the library where he works. Mineral Resources, Inc., plans to drill wells near the charter elementary school Frontier Academy, located behind Graham’s office. One of those wells will be drilled 478 feet from the school’s playground.

Graham said he feels betrayed by regulators and by the oil and gas industry.

“I’m a registered Republican, I own a diesel pickup and I’m from rural Colorado,” Graham said. “I think I fit most of those molds. Before all this, I didn’t like treehuggers, and I didn’t like Boulder and all that kind of stuff. But living here and being exposed to this, and seeing that stuff coming out of those smokestacks changed my mind.”

Graham’s neighbors who receive the royalties from the wells on their properties disagree, and urge Graham to “stop stirring the hornet’s nest,” as he said.

“I guess they think I’m going to ruin it for them, but that’s not what I’m about,” Graham said. “I just didn’t want the drill to be in my front yard. It just needed to comply with the laws—that’s all I’m about. I’m not trying to end oil and gas development.”

“But I’m getting there,” he added. “If you’re going to do it, it’s got to be done right. You can’t just come in and eliminate people’s rights in order to do it.”

Proceed to Chapter 5: The Conversation