ANSS Regional Advisory Committee Meeting
Date: September 25, 2002


University of Washington, PNSN labs

Report on National Implementation Committee (NIC) meeting in SLC

Steve M and CB Crouse reviewed sections of the NIC meeting relevant to PNW Advisory Committee issues. The NIC meeting primarily addressed policy issues and the production of guidance for next year's regional planning effort. Discussions of structural monitoring at the NIC meeting generate quite a bit of interest. While the original ANSS plan called for a 50/50 ratio of free field and structural sites there were regions (PNW and Northeast in particular) who felt that it was too early with too little funding to try and obtain that ratio. What we learned from the Nisqually earthquake was that we now need a greater portion of free field sites. Monitoring structures requires greater resources. In a situation with funding constraints one must choose between few structures or many free fields. Until we are at a higher level of funding we should stay on the present course of mostly installing free field sites. It might make more sense to put limited resources into monitoring structures in CA rather than the PNW, since these structures experience a higher seismicity rate and would likely provide a richer database. Also, while a portable array for ambient monitoring is still of interest to some in the PNW, the NIC and others feel that it should be done from funding sources other than ANSS, such as NEES.

The question was raised as to who has looked at the data from structures with recordings of the Nisqually earthquake. Known structures are the DNR building in Olympia, Tacoma General Hospital and the Crown Plaza in Seattle. There was some confusion about the quality and even location of the data. NSMP has DNR data, UW (George Thomas) has Tacoma General Hospital data but in a strange format. An engineering course at UW may try to use data from one of these structures but there were questions about the number of records available for fairly complex buildings. Several comments were made about the usefulness of the free field data in the weeks after Nisqually and that making those data quickly and easily available for future events was a high priority.

A discussion of down hole monitoring came up because of continuing problems understanding non-linear responses of soils during the Nisqually event. The committee encouraged ANSS to look into the possibilility of taking advantage of new or existing holes for such monitoring. (See later section on plans for next year). There were also questions regarding pore pressure sensors being funded by the ANSS. Since they are not specifically mentioned as part of the ANSS program their purchase and installation probably could not be funded by ANSS; however, it probably would be possible to have their data coordinated and possibly recorded along with ANSS data.

Rotation of Subcommittee members

After being in operation for two years it is time to start changing and rotating membership of the Advisory Committee and its subcommittees. Stephen Weiser and Mike Gallagher will rotate off of the Advisory Committee to be replaced by Bill Perkins and Susan Chang. Steve Malone was directed to contact John Beaulieu to get DOGAMI participation in the Advisory Committee. The lack of participation by any Oregon group, even by telephone for this meeting was seen as a big disadvantage.

Because of the importance of positioning ourselves to do structural monitoring in the future in an efficient way, a structures subcommittee was formed to be headed by John Hooper. CB Crouse will work with John to populate the committee with appropriate members. Several suggestions were made for asking individuals to be members.

Because of too many other responsibilities Paul Grant will step down as chair of the siting subcommittee but remain a member. Bill Perkins or Susan Chang will chair the committee. Steve Palmer volunteered to remain a member of this committee. Craig recommended that there be a member of Seattle DOT, DOGAMI, or BPA on the committee. A member of the Seattle Mapping Project should be on this committee. S. Malone recommended that someone from Art Frankel's group participate on the committee. The importance and urgency of this subcommittee's work is increased and thus a meeting of this subcommittee in the near future is a must. See below.

(subcommittee members will be added when available)

PNW ANSS current status

George Thomas reviewed recent installations: Three strong-motion stations, EYES, COLT and HUBA were installed in the greater Portland area in the past two weeks. These are essentially free field sites. SHIP (Seattle Ship Canal Bridge) had a continuous telemetry system installed along with the current dial-up NSMP instrument. Both instruments will operate at the same site for some overlap period. This is the first test of a of wireless-IP telemetry system in the PNW. Two new stations were installed in the Puget Sound region; SVTR is at a school in North Bend within a few km of ELW but on different geology, and MEAN is on Capital Hill in Seattle.

Other accomplishments are the hardening of existing free field sites with improved back-up power systems. This power system resolved an ongoing RFI problem at Camp Murray. Camp Murray has been taken over as a NSMP dial-up site because of the impossibility of getting easy continuous telemetry from it.

Information products development has proceeded very slowly. ShakeMap is still not automated and delivery of it other than via WEB pages has not been developed. Training in its use is of interest to EMD, but none is available yet.

Site Characterization

The importance of having site characterization information at strong-motion sites was discussed at length. Steve Palmer has a FEMA sponsored project for characterizing 10 sites via bore-holes of which three are to be in eastern WA and seven in western WA. Bore-holes will be about 30 to 50 meters deep. He will collect disturbed samples but can also do undisturbed samples if there is interest. He also plans to do standard Vp & Vs measurements at up to 100 other sites to try and get a good estimate of shallow velocities in all major soil types found in Washington. Steve still needs to identify 20 potential sites to finish his drilling proposal and is seeking advice from the ANSS siting committee. He could start the project within a few months and the project duration is 1.5-2 years.

Craig Weaver reported that a NEHRP external proposal has been funded to do shallow velocity surveys of about 30 sites in the Puget Sound area. This is independent of Steve Palmer's work but the committee hopes that there will be good coordination between these two groups.

Plan for next year

A formal ANSS PNW Regional plan for the coming year is due at the end of October. Steve Malone presented a tentative plan (partially based on previous discussions with the committee) for discussion and approval. The committee discussed and approved the following recommendations regarding siting for next year:

Reports on Cooperative or coordinated projects

Current cooperating agencies are the following:

New cooperative projects are the following:

Action Items

The siting subcommittee should be formed and meet soon to help identify sites for the Duwamish Array project and for Steve Palmer's characterization project.

The structures subcommittee should be formed and quickly review and finalize the identification of important structures in the area that should have, at least reference station near them and perhaps also for structural monitoring when ANSS funding reaches a higher level. This committee will ned some coordination with the siting committee for the reference station distribution.

Initial members of both the siting and structures subcommittees should be sent to Steve Malone within a week or so.

The next general Advisory committee meeting is tentatively scheduled for Jan. 15.

Addendum supplied by Ron Porcella regarding older instruments

Regarding the proposal to re-occupy the '49 and '65 NSMP accelerograph sites-- there were just two strong-motion sites that recorded the '49 event-the Highway Test Lab on State Ave in Olympia (epicentral dist = 16 km), and the Seattle Army Base (dist. = 60 km); both stations were established in October 1948.

The Olympia station is a freefield site, which was recently moved from the original 6' by 8' wood/metal storage shed to an adjacent 4 sq/ft fiberglass t-hut; it is currently instrumented with a K2. We've had some difficulty establishing telephone service (trenching expense) to this location, but are still working on it.

The second site was the ACOE Meteorological Station on the Seattle Army Base, at 4735 East Marginal Way. The instrument was in a small (8' by 10') wood-framed shed. The recording station was closed and the accelerograph was moved to the Seattle Federal Office Bldg in June 1953 (does the Seattle Army Base still exist?)

The '65 event was recorded at 5 NSMP stations: 1) on the ground floor of the 11-story, reinforced concrete State Office Bldg in Portland; 2) the crest station on the concrete Ross Dam; 3) in the sub-basement of the 9-story, steel-frame Federal Office Bldg in Seattle; 4) in the basement of the 10-story, concrete and steel County-City Bldg in Tacoma; and 5), at the Highway Test Lab in Olympia.

As I mentioned, the Olympia station still exists. The accelerograph at the State Office bldg in Portland was relocated in 1970. Seattle City Light recently took over responsibility for maintaining instrumentation at Ross Dam (which I understand was recently upgraded to Etna's, no comm.). And both the old Federal Office bldg in Seattle and the Tacoma County-City Bldg were on the list of structures recommended by the USGS Puget Sound Region Instrumentation Advisory Committee (Bruce Olsen, Chair), as priority candidates for extensive new seismic instrumentation (see USGS Open-File Report 89-374).