Uranium and radium are natural components of Colorado’s geology. Some of these radionuclides will dissolve out of soils and mineral deposits into water, resulting in areas with elevated levels of radionuclides in groundwater. Many small community water systems rely on groundwater as a drinking water source. Because of high costs of treatment and waste disposal, several small community systems are currently out of compliance with standards set in the Colorado Primary Drinking Water Regulations for safe levels of radionuclides in drinking water.
The primary effect of long-term exposure to radionuclides is cancer. It is important to note that cancer is found in one-third of the population, regardless of exposure to radiation or toxic chemicals. Drinking water standards and regulations are set to reduce any additional exposure that can be avoided. Many years of exposure to radiation and toxic chemicals can lead to unacceptable levels of exposure and increased adverse health effects.
Radionuclides, such as radium and uranium, are unstable compounds that degrade over time. As these compounds degrade, radiation is emitted, generally in one of three forms: alpha particles, beta particles, and gamma rays. When human tissue is exposed to such emissions, the DNA may be damaged and thus increase the risk of developing cancer. Alpha and beta particles are typically blocked by the skin and do not pose a risk if a person is exposed from external sources. Gamma rays can penetrate the skin and interact with internal tissue. Radium and uranium found in drinking water do not emit high amounts of gamma radiation, so bathing and showering do not pose significant risk. However, if these radionuclides are inhaled or consumed through drinking or eating, the emissions can come into direct contact with sensitive tissues in the body. Uranium is also a toxic heavy metal which can impact urinary tract/kidney systems over time.
Ensuring safe drinking water for the citizens of Colorado is a high priority for the Colorado Department of Public Health and Environment. In 2007, the department's Water Quality Control Division launched the Colorado Radionuclide Abatement and Disposal Strategy (CO-RADS) project to assist small, rural public water systems to meet and maintain compliance with drinking water standards for naturally-occurring radionuclides. CO-RADS is the largest compliance assistance program ever implemented in the State, providing innovative and unprecedented resources to help small water suppliers identify options and secure available funding to bring their systems into compliance.
CO-RADS is a voluntary program that will continue through 2011. The strategy is divided into five phases:
Phase 1: Identify affected communities
Phase 2: Sample system source water supplies
Phase 3: Treatment and waste disposal evaluations
Phase 4: Technical, managerial, and financial capacity-building
Phase 5: Implementation
Phase 3 was completed in March of 2009 and activities for Phase 4 are currently underway. The Phase 3 report is now available, and provides an overview of findings from the treatment and waste disposal evaluations. Presentation materials from the June 2009 Phase 4 Regional Meetings are also available.