Savannah River Site Health Effects Subcommittee (SRSHES) Meeting

Meeting Summary

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List of Acronyms
	ABRWH  Advisory Board on Radiation and Worker Health   ATL  Advanced Technology Laboratory  ATSDR  Agency for Toxic Substances and Disease Registry  CDC  Centers for Disease Control and Prevention  DOE  Department of Energy GDNR  Georgia Department of Natural Resources HESs  Health Effects Subcommittees HHS Department of Health and Human Services NCEH National Center for Environmental Health NIOSH National Institute for Occupational Safety and Health OCAS  Office of Compensation Analysis and Support  SCDHEC  South Carolina Department of Health and Environmental Control  SRS-50  Savannah River Site at Fifty  SRSHES  Savannah River Site Health Effects Subcommittee

HHS and CDC convened an SRSHES meeting on March 13-14, 2003 at the DoubleTree Guest Suites in Charleston, South Carolina. The September 5-6, 2002 meeting minutes were unanimously approved with changes as noted and submitted into the record. Current action items were completed by placing meeting notices in local publications and scheduling an agenda item. SRSHES members whose terms will expire on June 30, 2003 and are interested in continuing to serve were encouraged to complete and submit application packages to CDC by March 31, 2003.

SRS-50 is a historical narrative of SRS that examines a unique culture and technology within 20th century American history; the book was released in June 2002. Part 1 is the history of atomic energy; the establishment of the Atomic Energy Commission; predecessors to DOE; the history of DuPont at SRS; and biographies of SRS personnel. Part 2 is a chronicle of the construction era; a description of engineering achievements; and an overview of SRS cultural impacts. Part 3 is a history of the technology. Parts 4 and 5 are summaries of SRS's transition and the establishment of Westinghouse. SRS-50 contains an index, chronology, full citations, topography maps of SRS communities, and an appendix of cemetery locations where burials were relocated.

The Saturday Evening Post, Time Magazine, SRS newspapers, and a collection of SRS artifacts DuPont donated to a museum were used as data sources. Efforts are being made with South Carolina and local repositories to appropriately house, preserve and exhibit SRS artifacts collected for the book. Plans are also being made to consult with the South Carolina historic preservation officer to preserve artifacts in historical buildings at SRS. The preservation plan should not interfere with current efforts to de-commission, decontaminate and destroy onsite facilities that are no longer used, but are extremely expensive to maintain.

In August 2002, CDC awarded ATL the dose reconstruction contract to conduct screening with an endpoint of screening-level dose estimates for receptors in scenarios approved by SRSHES. In October 2002, CDC changed the scope of work and charged ATL with developing detailed release, transport and exposure models with endpoints of dose and cancer risks for target organs and the whole body. The new scope of work increased the size of the study and will require additional research and computer programming of ~260 variables. ATL reviewed and modified scenario locations recommended by SRSHES. For the air exposure pathway, the rural family in Clark Hill Lake will be combined with and moved to Augusta, Georgia. An additional rural family will be placed in Williston, South Carolina due to exposures in this area.

The migrant family will be placed in New Ellenton, South Carolina. For the milk exposure pathway, the dairy location for the urban family will be moved from Aiken, South Carolina to New Ellenton. The number of source and receptor locations will be decreased from 20 to 10. In its technical approach, ATL will base releases on the Phase II report; incorporate scenarios developed by the Scenario Workgroup; apply generic environmental models; calculate endpoints of dose, risk and organ doses as needed; use SRS-specific characteristics to revise established models; review many exposure and source locations for each receptor; and evaluate quantitative and qualitative aspects of uncertainties associated with dose and risk. Dose calculations will be based on an existing risk assessment model and will include release, transport, exposure and consequence assessments.

Federal Radiation Guidance 13 will be used to qualify risk, such as probability of cancer incidence or cancer death. ATL plans to conduct separate studies to calculate acute short-term releases because spikes are averaged over one year and will not be precisely reflected. The potential for total dose buildup in soil concentrations and other factors will be used to account for variability in annual releases. If ATL is unable to select solid figures, conservative values will be chosen. ATL has initiated computerized analyses with the GENII version 2 computer code to specify the transport of radionuclides in the environment and exposure variables of persons. The computation size for the study is extremely large with >300 million data points: 39 years, 30 radionuclides, 4 exposure pathways, 10 transport pathways, 25 receptors, 10 release points and 30 exposure locations.

ATL is proposing to combine air and water release points and merge exposure locations to make the model simple, tractable and representative of actual doses. To address several outstanding issues in the Phase II report, ATL added source terms for unspecified alpha and beta releases; added to or deleted from isotopes listed in the Phase II report; and partitioned some radionuclide releases into one isotope. ATL is attempting to develop a source term that can be divided by the flow in the Savannah River to address environmental holdup of releases. Modeling these parameters is difficult because the environment may store contaminants, liquid pathway releases and air releases in contaminated soil.

To support the main computation, ATL will perform auxiliary analyses for air dispersion, surface water transport and soil buildup. All findings will be compiled in a draft report. SRSHES unanimously passed a resolution in response to ATL's revised scope of work. A Letter Writing workgroup should be formed to outline concerns about CDC's lack of communication on ATL's revised scope of work and technical issues these changes may cause in the future.

GDNR's Environmental Radiation Monitoring Program was initiated in 1977 and monitors SRS, Plant Vogtle and other facilities once or twice per month. Matrices tested around SRS include direct radiation samples from thermoluminescent dosimeters; air samples from filters, charcoal cartridges for iodine-131 and silica-gel cartridges for tritium; water samples from river water, ground water and precipitation; soil and river sediment; vegetation, crops, milk and game; and fish and seafood. Radionuclide concentrations in the vast majority of samples collected from all pathways have been below detectable limits.

SRS, Chernobyl and weapons testing were the most common sources of radionuclide concentrations based on GDNR's monitoring data. GDNR, SRS, the state of South Carolina and the city of Savannah are closely tracking any changes in tritium releases in the Savannah River. GDNR, Georgia Power, SCDHEC and SRS share findings twice per year. Data collected by the agencies are generally found to be consistent. GDNR expects to publish an updated environmental radiological monitoring report in the next month. The document will contain GDNR's dose calculations, risk estimates and technical approaches.

ABRWH is chartered to advise the HHS Secretary in three specific areas: guidelines for implementing the Energy Employees Occupational Illness Compensation Program Act; the scientific validity and quality of dose reconstruction; and a class of employees exposed to radiation at DOE facilities for which a dose reconstruction would not be feasible and radiation exposure may have endangered health. DOE is mandated to establish a panel of physicians to determine whether workplace toxic chemicals contributed to illness. Claimants with a positive diagnosis are to be referred to the state workers' compensation program.

With assistance from NIOSH, the Department of Labor is mandated to reconstruct doses of claimants and identify recipients for $150,000 in compensation. NIOSH established OCAS to interact with and serve as a point of contact for claimants. As of December 31, 2002, 6,825 requests for worker monitoring and workplace data were sent to DOE. Of 1,302 requests for worker monitoring and workplace data submitted by OCAS to SRS, 499 responses have been provided. As of January 2003, 10,472 claims had been submitted and 18 dose reconstructions were completed, but no awards were made as of that time. Compensation is made if the probability of cancer causation is calculated to be >50% at a 99% confidence interval based on an overall probability of cancer distribution for each organ and different exposures to each organ. A contractor will collaborate with ABRWH to assist in performing quality reviews of dose reconstruction calculations.

ATSDR asked SRSHES to compile comments on the final internal version of the health education needs assessment and develop a plan to collectively submit revisions. NIOSH recently completed several extramural projects: heat stress associated with remediation work by carpenters at Hanford; glycophorin biodosimetry among patients treated with iodine-131; surveillance methods for solvent-related hepatotoxicity among painters, carpenters and millwrights at Hanford; and a lung fibrosis study among plutonium workers at Los Alamos and Rocky Flats. NIOSH awarded three new grants in 2002: health effects of occupational exposures among Paducah Gaseous Diffusion Plant workers; stochastic models for radiation carcinogenesis to identify temporal factors and dose-rate effects; and susceptibility and occupational radiation risks. This cohort will include SRS workers.

Several research projects are expected to be completed and communicated in 2003: an epidemiological evaluation of cancer among Rocky Flats workers; an ionizing radiation and mortality study among Hanford workers; an assessment of radon and cigarette smoking exposure among Fernald workers; cohort mortality studies of workers at three different DOE sites; several beryllium disease studies among exposed workers; epidemiological studies to evaluate health effects of uranium milling; an analysis of corrections in measurement errors of radiation exposure; an uncertainty analysis to characterize plutonium exposure and improve lung cancer risk estimates; and a dose reconstruction of Chernobyl liquidators. Completed and ongoing research projects of workers at SRS and all other DOE sites can be accessed on the NIOSH web site.

The Scenario Workgroup made several recommendations in response to the ATL status report. Assumptions, the basis for assumptions and the impact of any exclusions should be well documented, including the modeling process and computer codes. Results should be benchmarked against actual monitoring data collected by GDNR, SCDHEC and WSRC when practical. SRSHES's concerns about merging data and eliminating the screening process should addressed. Drinking water pathways from rain and river water should be added to the scenarios.

Scenarios should reflect worst-case realistic scenarios. Dose contributions from non-SRS source terms should be identified and quantified if applicable. SRSHES should be provided an opportunity to comment on ATL's protocol. An elderly individual should be included in one scenario. An explanation should be provided for the discrepancy between 11 radionuclide source terms in the RAC report and >30 radionuclides in ATL's technical approach. SRSHES should be provided an opportunity to develop a scenario for a family living by the water. SRSHES passed a resolution with a majority vote and one abstention for the workgroup's recommendations to be submitted as a guidance document to CDC and ATL for a response.

The Epidemiological Data Workgroup reviewed its charged and determined that an updated review of current epidemiological data that may impact SRS should be presented by an epidemiologist at the next meeting. The workgroup expressed concerns about ATL's plans to use overly conservative estimates in the dose reconstruction project because this approach is unlikely to generate findings at a significant level that would justify an epidemiological study. Doses with higher levels and longer exposure periods should be used in ATL's calculations instead of a mid-point of lower and upper ranges ². SRSHES unanimously passed a resolution for CDC to distribute ATL's monthly progress reports to SRSHES.

The Outreach Workgroup distributed mock copies of the new SRSHES brochure. SRSHES was asked to edit the mock copy and submit additional changes to ATSDR by the end of the meeting. The workgroup will provide each SRSHES member with 100 copies of the brochure for distribution in their respective communities, city councils, school boards, hospitals, other local groups and local publications. A total of 5,000-10,000 copies are expected to be printed. The brochure will also be translated into Spanish. CDC will assist the workgroup in improving the SRSHES web site and will explore the possibility of establishing an SRSHES mailbox to receive e-mail messages from the public. SRSHES unanimously passed a resolution to use the mock copy as the official version of the brochure after minor changes have been made.

The Agenda Workgroup will convene a face-to-face meeting to discuss three epidemiologists the Epidemiological Workgroup recommended to make a presentation at the next meeting. The workgroup is compiling a list of outstanding agenda items to identify topics that are still relevant versus those which should be removed from the SRSHES agenda. A report on these findings is expected to be presented at the next meeting.

SRSHES reviewed new action and agenda items raised during the meeting. Votes were properly taken for all consensus recommendations. The Chair opened the floor for public comment at all times as designated on the agenda. The next SRSHES meeting will be held on September 4-5, 2003 in Savannah, Georgia. The following SRSHES meeting is scheduled for March 25-26, 2004 in Columbia, South Carolina.

 

² One SRSHES member noted that the observations by the Epidemiological Data Workgroup reflect a misunderstanding of ATL's use of the word conservative. Use of conservative values in dose calculations will generate higher doses.