U.S. Geological Survey, Branch Of Acquisition and Federal Assistance, Box 25046, Denver Federal Center, Denver, CO 80225-0046

B -- CONDUCT DETAILED HIGH-RESOLUTION SWATH BATHYMETRIC SURVEY OF YELLOWSTONE LAKE SOL 00CRQQ0216 DUE 060700 POC Robert Valdez (303) 236-5900 ext 424 The U.S. Geological Survey, Geologic Division, has a requirement to conduct a detailed high-resolution swath bathymetric survey of Yellowstone Lake in order to locate and image bottom features such as hydrothermal deposits, hydrothermal explosion craters, rock outcrops, slump blocks, fault zones, boulder and cobble deposits (possible fish spawning areas), archeological and historical features (old piers, building foundations, sunken boats, etc.) and submerged shorelines. The survey will be conducted using a hull-mounted high resolution swath sonar mapping instrument such as commercially produced SeaBeam or SimRad instruments. Such systems use multibeam sonar to map a swath (perpendicular to survey lines) with a width of about 8 times water depth. The actual accuracy and precision of the depth survey depends on many factors including water depth, nature of bottom material, and roughness or steepness of the bottom topography. However, we expect that features less than a meter high will be resolved and accurately mapped. Areas to be mapped and location of survey lines will be planned with USGS personnel on site, and will be arranged to maximize coverage and overlap of lines. Lines will be navigated with differential GPS provided by the contractor and the relative error of boat position will be less than +/- 2 meters. The area to be surveyed requires 7-8 days of data collection on the lake. Seismic reflection data will be simultaneously collected using the USGS Edgetek Chirp instrument at a speed of about 5 knots. Contractor shall provide personnel on-site who are experienced in all facets of swath sonar surveys. Interested parties shall complete the Request for Quotation 00CRQQ0216 at the following web site: http://ideasec.usgs.gov/. Posted 05/19/00 (W-SN456914). (0140)

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