Annual Hanford Seismic Report for Fiscal Year 1998

Seismic monitoring at the Hanford Site was established in 1969 by the United States Geological Survey (USGS) under a contract with theJ.J.S. Atomic Energy Commission. In 1975, the University of Washington (UW) assumed responsibility for the network and subsequently expanded it. In 1979, the Basalt Waste o Isolation Program (13WIP) became responsible for collecting seismic data for the Hdord Site as part of site " characterization activities. Rockwell Htiord Operations, followed by Westinghouse Ha&ord Company . (WHC), operated the local network and were the contract technical advisors for the Eastern Washington Regional Network @wRN) operated and maintained by the UW. Funding for BWIP ended in December 1988. Seismic Monitoring and responsibility for the University of Washington contract were then trans- ferred to WHC'S Environmental Division. Maintenance responsibilities for the EWRN were also Assigned to WHC, who made major upgrades to EWRN sites. Effective October 1,1996, Seismic Monitoring was transfemed to the Pacific Northwest National Laboratory (PI@lL*). Seismic Monitoring is part of PNNL's Applied Geology and Geochemistry Group, Energy Technology Division. The Hanford Strong Motion Accelerometer network was constructed during 1997 and came online in May 1997. It operated continuously until September 30, 1997, when it was mothballed due to can- . cellation of fimding. Funding was restored on October 1, 1998, by joint agreement between the U.S. Department of Energy (DOE) and PNNL. Operation of the free-field sites resumed on November 20, 1998