Oil and gas companies in Colorado are injecting wells with millions of gallons of unknown fluids that contain dozens of dangerous chemicals linked to respiratory, neurological, cardiovascular, immune, and other disorders, including cancer.

According to industry data, at least 430 million gallons of chemical-laced fluids have been injected into more than 9,000 oil and gas wells in the state, mostly along the northern Front Range and the Western Slope. The amount of fluid injected may be far greater than reported: There are currently more than 35,000 wells operating in Colorado and one industry expert has estimated that 90 percent of all wells receive chemical injections (COGCC 2008, Carrillo 2005).

Locations of Wells Receiving Chemical Injections

Source: IHS Energy (IHS). 2008. PI/Dwights Plus Energy Well Data, Rocky Mountain, Volume 18, Issue 5, Released May 1, 2008.

The analysis by Environmental Working Group and The Endocrine Disruption Exchange (TEDX), a research organization based in Paonia, Colo., found that at least 65 chemicals used by natural gas companies in Colorado are listed as hazardous under 6 major federal laws designed to protect Americans from toxic substances. If any one of these 65 chemicals were emitted or discharged from an industrial facility, reporting to the US EPA would be mandatory, and in most cases permits would require strict pollution limits and companies would be subject to specific cleanup standards. But because these same chemicals are used in natural gas drilling operations they are completely exempt from environmental reporting requirements, and their use is not controlled in any meaningful way.

While energy companies use toxic chemicals for a variety of purposes and can extract toxic materials as byproducts of the drilling process, the injection of toxic chemicals underground raises particular concern because of the risk of contaminating drinking water sources. Chemicals are typically injected in processes called "hydraulic fracturing" or "acidizing" that are used to increase oil and gas production. Because neither state nor federal law regulates such injections, or even requires companies to report the chemicals they use, the practice raises serious concerns about toxic chemicals leaching into water and soil.

Our analysis also identified more than 150 other chemicals or chemical mixes used in these operations that are not regulated by these 6 major environmental laws. The fact that these chemical products are not listed under the 6 laws does not mean that they are safe -- it simply reveals the magnitude of the shortcomings in these federal laws when it comes to protecting the environment and human health from chemicals used in oil and gas drilling operations.

Despite a record number of wells approved in Colorado -- more than 6,300 in 2007 versus just 2,900 in 2004 -- state and federal officials and the public have almost no idea how any of these industry chemicals are used, whether or not their use threatens water supplies, pollutes the local air, or presents a risk to public safety. This is true even when these chemicals are considered highly toxic, or an "imminent and substantial danger" to health and the environment under federal environmental laws. Dozens of pesticide ingredients are also used by the natural gas industry in Colorado.

These findings are released as Colorado's Oil and Gas Conservation Commission prepares to hold its latest hearing, June 10 in Grand Junction, as part of a landmark process to rewrite the state's drilling standards. Among the protections that the Commission is considering is a requirement that companies provide limited disclosure of the chemicals they use. But limited disclosure is not enough to ensure protection of public health and the environment. This analysis clearly shows that comprehensive reporting and public disclosure of all chemicals used in oil and gas operations is a mandatory first step toward understanding the magnitude of the environmental and health threat, if any, that may be posed by these operations.

Wells Receiving Chemical Injections in Colorado by County