Hanford Radiological Protection Support Services Annual Report for 1999

Abstract

During calendar year (CY) 1999, the Pacific Northwest National Laboratory (PNNL) performed its customary radiological protection support services in support of the U.S. Department of Energy (DOE) Richland Operations Office (RL) and the Hanford contractors. These services included: (1) external dosimetry, (2) internal dosimetry, (3) in vivo measurements, (4) radiological records, (5) instrument calibration and evaluation, and (6) calibration of radiation sources traceable to the National Institute of Standards and Technology (NIST). The services were provided under a number of programs as summarized here. Along with providing site-wide nuclear accident and environmental dosimetry capabilities, the Hanford External Dosimetry Program (HEDP) supports Hanford radiation protection programs by providing external radiation monitoring capabilities for all Hanford workers and visitors to help ensure their health and safety. Processing volumes decreased in CY 1999 relative to prior years for all types of dosimeters, with an overall decrease of 19%. During 1999, the HEDP passed the National Voluntary Laboratory Accreditation Program (NVLAP) performance testing criteria in 15 different categories. HEDP computers and processors were tested and upgraded to become Year 2000 (Y2K) compliant. Several changes and improvements were made to enhance the interpretation of dosimeter results. The Hanford Internal Dosimetry Program (HIDP) provides for the assessment and documentation of occupational dose from intakes of radionuclides at the Hanford Site. Performance problems carried over from CY 1998 continued to plague the in vitro bioassay contractor. A new contract was awarded for the in vitro bioassay program. A new computer system was put into routine operation by the in vivo bioassay program. Several changes to HIDP protocols were made that were related to bioassay grace periods, using field data to characterize the amount of alpha activity present and using a new default particle size. The number of incidents and high routine investigations that required follow-up were lower compared with 1998. Also, the number of excreta analyses performed decreased compared with CY 1998. The In Vivo Monitoring Program for Hanford (formerly the Hanford Whole Body Counting Project) provides the in vivo counting services for Hanford Site radiation workers. New computer hardware and software were put into routine operation to acquire, analyze, and store the measurement data. The technical procedures were revamped to reflect operational changes implemented with the new computer system. The U.S. Department of Energy Laboratory Accreditation Program (DOELAP) accreditation was extended to include two additional categories. New detectors were purchased for wound counting applications. The 8,085 in vivo measurements performed in 1999 represent a 2% decrease from 1998. Several high-purity germanium detectors were repaired at the In Vivo Radioassay and Research Facility, thereby saving out-of-service time and money compared with returning the detectors to the vendor. There were 11 phantom loans made through the DOE Phantom Library in 1999, including 2 international loans.