Sampling Programs

Air

Overall Air Programs

As of January 1, 2008

The RadNet Air Program consists of 91 sampling locations. Approximately 5 air particulate monitors are currently being installed per month. Continuously operating samplers collect airborne particulates on filters that are collected twice weekly and sent to NAREL for analysis. A gross beta analysis is performed on each air filter, and a gamma scan is done if the beta activity is greater than 1 pCi per cubic meter. Annual composites of the air particulates filters are analyzed for plutonium (Pu-238, Pu-239, Pu-240) and uranium (U-234, U-235, U-238).

Expansion and Upgrade of Air Program

The RadNet air program is undergoing an expansion and upgrade. The number of sampling stations is targeted to be approximately 160 by 2011. All new air stations will provide gamma data in near-real-time that will be transmitted to a central database accessible to both decision makers and the public. The new monitors will continue to submit filters twice weekly for fixed laboratory analyses, and all new real-time sites will be equipped with an alpha/beta counting system, which improves upon the traditional beta only capability. As of February 2007, 23 near-real-time monitors are sited. The locations of these new monitors are shown Air Program page. The expanded and upgraded system is intended to improve geographical and population coverage and better support response to potential national radiation emergencies.

Analytical Scheme And Primary Rationale For Routine Operations

This printable map shows the locations of the RadNet Air Sampling Stations. Click on the map for a larger view.

Drinking Water

The RadNet Drinking Water Program obtains quarterly drinking water samples from 78 sites, which are primarily major population centers. The samples are analyzed for tritium (H-3) quarterly, for gross alpha and beta on annual composite samples from each station, for iodine-131 (I-131) on one sample per year from each station, and for strontium-90 (Sr-90) on one-fourth of all the individual station annual composite samples. All of the annual composite samples are also analyzed by gamma spectrometry. Analyses for radium-226 (Ra-226), plutonium (Pu-238, Pu-239, and Pu-240), and uranium (U-234, U-235, and U-238) are performed if a sample shows elevated gross alpha radioactivity. If the radium-226 result is between 3 and 5 pCi/L, then a radium-228 analysis is performed.

Analytical Scheme And Primary Rationale For Routine Operations

This printable map shows the locations of the RadNet Drinking Water Sampling Stations. Click on the map for a larger view.

Milk

The RadNet Pasteurized Milk Program consists of 36 sampling locations that represent a significant portion of the milk consumed in major population centers. Milk is sampled because it is a readily available food source consumed by a large portion of the population; because it is consumed by children in relatively large quantities, which provides a good indication of children's exposure to nuclear events; and, finally, because it is a good indicator of radionuclides present in the environment. Primary functions of this program are to obtain reliable monitoring data about current radionuclide concentrations and to monitor long-term trends. The quarterly samples are analyzed by gamma spectrometry, looking for fission products such as iodine 131 (I-131), barium 140 (Ba-140), and cesium 137 (Ce-137), which could become present in the event of a nuclear accident. On a less frequent schedule, strontium 90 (Sr-90) is determined.

Analytical Scheme And Primary Rationale For Routine Operations

This printable map shows the locations of the RadNet Milk Sampling Stations. Click on the map for a larger view.

Precipitation

The RadNet Precipitation Program consists of sampling stations at 44 locations. All stations routinely submit precipitation samples as rainfall, snow or sleet occurs. The precipitation samples are composited at NAREL into single monthly samples for each station. Each month that precipitation occurs, an aliquot of each monthly precipitation sample is analyzed for tritium (H-3), gross beta, and gamma emitting nuclides. Also, a composite of the March, April and May monthly composites is analyzed.

Analytical Scheme And Primary Rationale For Routine Operations

This printable map shows the locations of the RadNet Precipitation Sampling Stations. Click on the map for a larger view.