ply source, particularly a bedrock well, contributes the next largest amount. My company does thousands of water and air tests for radon each year for commercial clients. Banks that are lenders require radon testing before a real estate loan can be secured. Real estate investment companies require radon testing before property is purchased. The federal government requires radon testing for any new development that is a federal project or federally funded.
Radon Hazards for Well Drillers There is certainly a true risk for well drillers who might be exposed to radon. This is especially true if radon exposure is combined with:
• the concentration of the radon gas • the frequency of exposure • the person is a smoker, has high blood pressure, or decreased lung capacity. If a contractor works in areas with a high probability of radon in the water table, they most likely will have an exposure to radon if when they’re drilling they hit the water table and drill down farther below it.
Precautions Well Drillers Can Take The precautions for water well contractors who might be exposed to radon are safety actions they should take anyway once they hit the water table. They should not work directly over the wellhead without good ventilation, even if they just use a fan to blow the radon out of their breathing zone or use wind direction to work upwind. If the contractor is setting the wellhead or setting pipe, they might have to work in closer proximity to air coming out of the wellhead. Time and distance away from the wellhead are both good factors for avoiding breathing in radon. Even a distance of 1 or 2 feet makes a huge difference if a person is outdoors as gases tend to dissipate quickly in the open air environment. When we analyze exposure on the job, we look at it in 8-hour timeweighted exposures to hazardous air pollutants over time. This means the duration of exposure over the workday, typically 8 hours, and the concentrations during that time period. For the water Twitter @WaterWellJournl
well contractor, this might mean there is the potential to exposure periodically during the time when drilling is occurring, and peak concentrations when water is reached. Minimizing these peak exposures will reduce the overall daily exposure to radon. States have specific requirements for drinking water, but not all states require radon testing. State testing examines radio nuclei (different isotopes that could be in the water) but not necessarily radon. The EPA has a recommended standard that is being reviewed. If it becomes a regulated standard, it will be enforced either by the EPA or the individual state for testing radon in drinking water. I recommend always taking an air or water sample for radon and having it tested. While the costs will vary between laboratories, a test typically costs between $25 and $50. That’s not that much when it might protect you from the health hazards in breathing in or ingesting radon gas. The Occupational Safety and Health Administration has guidance documents on radon, but not standards. However, OSHA can cite a company for failure to act on a recognized hazard, which radon is, under the General Duty Clause. It is also considered an ionizing radiation source, for which there is a standard, but again the standard does not specifically cite radon. Training in radon awareness would be a plus and can be addressed from the standpoint of encouraging workers to be more aware that it does exist. Make sure workers know that radon can be found in most water tables throughout the country at various levels, so it is important they increase their Circle card no. 27
awareness and understand the nature of this hazard. Plus, this information and heightened awareness is something they can apply to their own homes as well. WWJ
Best Suggested Practice for Radon The National Ground Water Association has a best suggested practice for dealing with concentrations of radon in well systems. Reducing Problematic Concentrations of Radon in Residential Well Systems, an 8-page document, is free to NGWA members and can be downloaded in the Online Bookstore at www.NGWA.org/Bookstore.
More Information Additional help is readily available on these Web sites: Centers for Disease Control www.cdc.gov/healthywater/drinking/ private/wells/disease/radon.html U.S. Environmental Protection Agency www.epa.gov/radon/index.html National Radon Program Services www.sosradon.org
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