United States 

Environmental Protection Agency

Radiation Health

and Safety Practices

for Community

Water Systems

Minimizing Worker Exposure to 

Radon and Radiation at Community 

Water Systems (CWSs)

Provided by: 

Office of Radiation and Indoor Air (ORIA)

Office of Ground Water & Drinking Water (OGWDW)

May 2008

EPA 402-F-08-003

Treatment of Water for Human Consumption 

Water treatment practices purify water for human consumption 

by removing levels of naturally occurring radioactive materials 

found in raw water supplies. As large quantities of water are 

treated using a filtration process, these contaminants become 

concentrated in various filtration media and wastes. Typical 

activities during the water treatment process can potentially 

bring the worker within close proximity to these concentrated 

waste contaminants.

Disposal of Liquid and Solid Waste 

Treating water for naturally occurring radionuclides will result 

in residual streams requiring disposal which is regulated by 

EPA and/or States. Radionuclide concentrations in waste may 

determine the disposal options(s) available. These include: 

Liquid waste disposal

Direct discharge to surface water

Discharge to Publicly Owned Treatment Works

Solid waste disposal

Solid waste landfills*

Hazardous waste landfills

Low-level radioactive waste landfills

* Note that landfill owners can refuse to accept any waste. 

States may have additional requirements or restrictions 

on the disposal of these residuals containing radionuclides. 

The practice of land spreading, as an alternative to landfill 

disposal of waste treatment residuals, is under review 

by EPA. 

Additional Resources

Drinking Water Standards: 40 CFR Parts 8, 141, and 142.

A Regulator’s Guide to Management of Radioactive 

Residuals from Drinking Water Treatment Technologies. 

U.S. EPA Office of Water, July 2005 (EPA Publication 

No. 816-R-05-004).

Narasimhan, R., J.D. Lowry, J. Culley, and N. YoungPong, 2005. Management of the Disposal of Radioactive 

Residuals in Drinking Water Treatment. American Water 

Works Association (AWWA) Research Foundation.

www.epa.gov/radiation/tenorm/water-treatment.html

Radiation and Public Health

Human beings are constantly exposed to radiation from 

natural and manmade sources. On average, 80 percent 

of that exposure comes from natural sources, including 

terrestrial radiation from radioactive elements such as 

uranium, radium, and radon that occur naturally in rocks, 

soil and minerals. Radiation exposures vary according to 

factors such as an individual’s location, lifestyle, occupation 

and daily activities. 

Radionuclides in Drinking Water

Uranium and radium naturally present in underground 

rocks that serve as aquifers may dissolve and enter 

groundwater used for drinking water.

Most drinking water 

sources have very low 

levels of radioactive 

contaminants 

(“radionuclides”), and 

are not considered to 

be a public health concern. Of the small percentage of 

drinking water systems with radioactive contaminant levels 

high enough to be of concern, most of the radioactivity is 

naturally occurring.

If source water comes from a geographic area where 

radiation releases are documented or likely to occur due 

to the presence of natural radionuclides in rocks or soil, a 

Community Water System (CWS) should test both source 

water and water treatment residuals to determine their 

radionuclide contents. 

Radionuclide Rule

To protect public health, EPA has established drinking 

water standards for the following radioactive contaminants:

Combined radium 226/228 (5 pCi/L);

Man-made beta particles and photon emitters 

(4 millirems per year);

Gross alpha activity (15 pCi/L); and

Uranium (30 μg/L).

Reducing the exposure to radionuclides in drinking water 

and filtration equipment or wastes containing radionuclides 

will reduce the risk of cancer. (For details see EPA’s 

Radionuclide Rule; 66 FR 76708, December 7, 2000.)
What Can a CWS Do to Reduce 

Worker Exposure?

Contact your State radiation program for guidance on 

conducting radiation surveys at the facility.

Changes to Facility:

Ventilate all buildings to remove radon gas, especially 

those buildings where waste with radium is stored.

Locate treatment units and waste storage areas as far 

away from common areas (e.g., offices) as possible.

Survey the system’s ambient radiation levels annually 

in areas where treatment takes place or material 

can accumulate.

Monitor levels of radiation to which staff is exposed.

Provide workers OSHA-approved respirators (not 

dust masks) when handling media to minimize 

inhalation of radioactive particulates. Note that 

respirators are not effective against radon gas. 

Provide workers with dosimeters to monitor radon 

levels around the facility.

Changes in Personal Hygiene Practices:

At home, wash work clothing separately.

Avoid wearing contaminated clothing into the home.

Keep work boots or shoes clean; after potential 

contamination, do not bring them home.

Changes in Work Practices:

Limit time spent near filtration and aeration equipment, 

backwash spray, waste sludges and scales, waste 

lagoons, pits and ponds.

Follow OSHA measures to limit the potential ingestion 

of heavy metals and biological pathogens present 

in filters.

Use protective gloves and frequently wash hands. 

Avoid plunging hands/arms in filtration tanks.

Avoid eating and drinking in the work area.

Shower after exposure to potentially radioactive materials.

Launder work clothing at the system if possible.

Radioactively

Contaminated

Wastes

Chlorine Storage

Drinking Water Well

Lime Alum

Mixing

Chemical Addition

Filtration

Sedimentation

Distribution

Coagulation & 

Flocculation

Disinfection

Water Contaminated

with Radionuclides

Untreated

Partially Treated

Meets EPA Standards