The measurement of naturally occurring radioactive material (NORM) in soils and sludges associated with oil field production sites and waste pits traditionally has been performed by estimating radium-226 levels using gamma scintillation detectors and selective laboratory measurements on solid samples. NORM contamination in pits and ponds pose a particular challenge in terms of manpower and cost using current sampling and evaluation methods. Physical conditions and sample costs often limit the number of samples that are collected, and potentially results in serious errors in estimating NORM waste.
This paper will discuss a direct in-situ measurement technique to detect radium-226 which has been developed to overcome the limitations of standard NORM sampling techniques. Operational experience has demonstrated the effectiveness of this method for remediation which provides low cost and near real-time analysis for radium-226 in the subsurface. A case study is presented using this technique for a NORM pit remediation.