Radionuclides in Drinking Water
Point of Use (POU) TechnologiesPoint-of-use (POU) water treatment devices are designed to treat small amounts of drinking water for use in the home. These devices can sit on the counter, attach to the faucet, or be installed under the sink. They differ from point-of-entry (POE) devices, which are installed on the water line as it enters the home and treat all the water in the building. For the purposes of radionuclides removal, one type of POU device using reverse osmosis is (POU reverse osmosis). EPA has developed guidance which provides public water systems and States with the Environmental Protection Agency’s current policy on point-of-use and point-of-entry devices used for compliance. Point-of-Use or Point-of-Entry Treatment Options for Small Drinking Water Systems (PDF, 132 pp, 791 KB) EPA 815-R-06-010 April 2006
Point-of-use reverse osmosis has been identified by EPA as a Small System Compliance Technology (SSCT) for radium, uranium, gross alpha, and beta particle and photon activity removal for systems serving up to 10,000 customers. Point-of-use reverse osmosis units can reduce gross alpha particle activity through the removal of radium-226 and uranium, inorganic chemicals, microbial contaminants, metals, minerals, and some organic chemicals. In certain systems, POU units may be more cost effective for very small communities that do not have the financial capacity to build a centralized treatment facility. Either the water system or a contractor would own, control, and maintain the units. The costs of installing POU units are generally moderate.
POU reverse osmosis units are NSF-certified for radium removal but not for uranium removal. Operations and maintenance costs for these units can be high. Some states do not allow POU or POE units for complying with an MCL.
Systems that install POU devices should also develop a routine program for maintenance and monitoring, as homeowners may not understand how the units function or the steps that should be taken to ensure that the treatment is effective. The treatment unit vendor may be able to help with monitoring and maintenance to some extent.
Disposal may be limited by state and local restrictions, but spent cartridges can generally be disposed of with household waste.