Monitoring stations in Warramunga and Tahiti certified

Two stations in the International Monitoring System (IMS), primary seismic station PS18 in Tahiti, French Polynesia, and infrasound station IS7 in Warramunga, Australia, were certified on 13 September 2001. This brings the total of certified IMS stations to 14. Under the terms of the Comprehensive Nuclear-Test-Ban Treaty, a global verification regime to monitor adherence to the Treaty must be in place at entry into force. The IMS is a key component of the verification regime. Seismic station PS18 is located on the island of Tahiti in French Polynesia. The station is part of the Department of Analysis, Monitoring and Environment (DASE) of the French Atomic Energy Commission, and is part of their geophysical observatory at Patamai. The station, originally built in 1985 as part of the French national seismograph network and selected as an IMS station during the negotiations for the Comprehensive Nuclear-Test-Ban Treaty, was upgraded by DASE to PTS specifications during 1998-2001. A certification visit by PTS technical staff was conducted in May 2001. Two other IMS stations on Tahiti, infrasound station IS24 and radionuclide station RN27, are being considered for certification this year. Infrasound station IS7 is located at Warramunga, 37 km southeast of the township of Tennant Creek in Northern Territory, Australia. The station is co-located with primary seismic station PS2, which was certified in 2000. The Warramunga Research Station (PS2 and IS7) is owned and operated by the Australian National University (ANU). Prior to the establishment of IS7, ANU built a seven-element infrasound array at Warramunga in 1975 to detect atmospheric nuclear explosions. Experience with this array played a key role in planning the IMS infrasound network. Site preparation was carried out by ANU from November 1999 to May 2000, and equipment was installed by the PTS in May 2000. A certification visit by PTS technical staff was conducted in March 2001.