Document: NRC Regulatory Guide
Document ID: 688895c2-d1d9-44f3-9c79-3cf0daa88510
Document Type: regulatory_guide
Title: 
Source: NRC Regulatory Guide Division 4
Source URL: https://www.nrc.gov/docs/ML0037/ML003739541.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-4.5
CFR Part: 
CFR Title: 

Content:
the detection limit of state.of-the-art equipment, and should be of little significance in terms May 1974 JIDE of exposure to humans. Nevertheless, the long half-life (24,390 years) of the predominant plutonium isotope, Pu-239, coupled with its high relative radiotoxicity, make it desirable to document and periodically reassess its distribution and fate in the environment. A soil sampling and analysis program provides the most direct means of determining the concentration and distribution of radionuclides in the environs of nuclear facilities. Hence, it would be desirable to include in environmental monitoring programs, a program for sampling and analyzing soil for plutonium. A soil analysis program would have the most significance for the preoperational monitoring program since it would serve to establish baseline concentrations of plutonium prior to operation of the facility. Soil analysis, although useful in special cases involving unexpected releases, is a poor technique for assessing small incremental releases and is therefore not recommended as a method for monitoring routine releases of radioactive material. Nevertheless, because soil is an integrator and a reservoir of long-lived radionuclides, and serves as an intermediary in several of the plutonium pathways of potential importance to humans, for example, resuspension and plant uptake, knowledge of the buildup of plutonium and other long-lived radionuclides in soil is essential. A soil-monitoring program conducted annually should be adequate to assess the cumulative deposit of plutonium in soil. C. REGULATORY POSITION The sampling and analytical procedures described in the appendices to this guide are acceptable to the Regulatory staff as bases for meeting the performance standards required to adequately inventory the plutonium deposited in the environs of nuclear facilities. Other procedures selected for sampling and analyzing plutonium in soil should conform to similar standards of performance. USAEC