We dispatched the boat to a crane company in Medford, OR and the boat and the equipment van were weighed using a NPS scale hung from a mobile crane. The boat and equipment van were then trucked to Crater Lake NP. Sunday afternoon was spent unpacking the equipment van, weighing each item in it, and then re-packing the van. In the late afternoon we were informed by NPS that a Monday helicopter lift was not possible but Tuesday morning remained a possibility.

Early Monday morning we were informed that the commercial helicopter would not be released from fire-fighting duties so the NPS immediately began to inquire about the possibility of a military helicopter. By Monday afternoon it appeared a high likelihood that a US Army Reserve Chinook helicopter could be called in to lift the boat into the lake.

We were told by the NPS at a 0800 hr meeting on Tuesday to truck the boat up to the rim of Crater Lake (Fig. 14) and prepare for a military helicopter lift at about noon. At about 0900 hr we were told that the military helicopter was in the air. However, at about 1100 hr we were informed that that there would be a two-hour delay in the arrival of the helicopter. And finally, at about 1600 hr we were told that there would be no helicopter lift on Tuesday and that a Wednesday lift was even questionable. Apparently, someone in the chain of military command in Atlanta, Georgia was holding up approval for the lift.

We were informed by the NPS early Wednesday morning that the US Army authorities in Atlanta were unwilling to give verbal approval and required signatures up their chain of command. They suggested this process might take several days. By 1100 hr we were informed that there would be no helicopter operations on Wednesday.

At this point, a discussion between C&C, UNH, and USGS determined that, if the boat was not in the lake by darkness on Friday, July 28th, then we would be forced to terminate the operation and pack up and depart because the cost of standby would begin to use operational funds. In addition, the multibeam, IMU, and workstations, as well as C&C personnel were required back in Lafayette by C&C Technologies for the mobilization of a class 1 research vessel in Hong Kong. That decision was passed on to Mr. Mack Brock, NPS at 1200 hr.

We were informed on Thursday morning that there would be no helicopter lift on Thursday because of military red tape. However, by late Thursday afternoon we were informed that there was a high likelihood that a military helicopter would be available Friday.

We were informed Friday morning that a military helicopter had been dispatched to Crater Lake to lift us into the lake. The helicopter arrived at 1415 hr and by 1530 hr the boat was in the water (Fig. 15) and by 1600 hr the equipment van was on Wizard Island. The remainder of the day was spent getting personal gear down the trail and setting up the field station on Wizard Island (Fig. 16).

The day was spent mapping the perimeter of the lake as close to the shore as was possible. Mark Buktenica (NPS) was stationed on the bow to guide the boat away from rocks.

All day was spent running north-south lines working from immediately east of Wizard Island toward the east. About 60% of the lake was mapped. However, when the data tapes were downloaded, we discovered that the navigation port was not sending navigation strings to the Simrad software, which means the datagram recorded by the Hydromap software had no navigation data. Fortunately, all the sensors, including navigation, are recorded separately as well as integrated into the Hydromap datagram, so we had navigation files. The problem was to reformat the DGPS data file so that it would be accepted by the processing software. We spent all evening devising a way to read in the DGPS GPGGA datagram into our processing software and finally, at about midnight, were successful.

The Wizard Island field station (Fig. 18) has a diesel generator and a bank of batteries charged with a solar panel and an inverter. We tested out the battery power by switching from the generator to the batteries with only the two workstations online. The UPSs (uninterruptable power supply) immediately started sounding alarms and one immediately shut off, crashing one workstation. The second UPS switched to its internal battery and allowed enough time to shut down the second workstation. The result of this test was that all computers had to be shut down each night.

We also discovered that all of the offsets between sensors had not been entered into the IMU (inertial motion unit) software nor into the mergeNav script. All the data from Saturday and Sunday had to be remerged with the appropriate offsets, then regridded and remosaicked.

The first thing Monday morning the generator would not start. Consequently, we had no power to the computers. We discovered that the generator the battery was dead. The battery was replaced and the generator was restarted.

Monday was “press day”; a morning that the press was allowed on the water in the NPS RV Neuston to photograph the RV Surf Surveyor actually mapping, as well as a visit to the field station on Wizard Island. Most of the day was spent reprocessing Saturday and Sunday’s data to correct for offsets and the navigation loss.

At 1245 hr the diesel generator powering the workstations ran out of gas and only one UPS backed up a workstation; the other UPS died, crashing the second workstation. Repeated efforts could not restart the generator, apparently because of debris sucked into the fuel filter when the diesel ran dry. Finally, at 1445 hr, with a cleaned fuel filter and diesel in the tank, the generator started and we got back to processing data.

The entire day was spent trying to reformat the various navigation files from Sunday’s data so that one of them could be read by our processing software. Finally, near midnight, a fix was devised and tested. The fix required reading the navigation file recorded by Hydromap.

The mapping continued throughout the day and all but a small deep-water area and some shallow-water areas were completed. Chaski slide was entirely mapped and the below-water segment appears to be a debris avalanche, similar to the one discovered in Lake Tahoe during the 1998 mapping (Gardner et al., 2000). The area of the crater’s rim directly above the slide has also failed and may be related to the below-lake failure (Fig. 19).

The mapping commenced by circumnavigating the lake twice to fill in data gaps and finally to beam-steer the transducer to ensonify as close to the shore as possible. Sunday’s data were processed, then Monday’s, and by 1000 hr the data processing was caught up with the data collection.

The day was spent filling in small gaps to insure 100% coverage. We collected the data tape at noon so that the processing could be finished in the evening in time for packing the equipment van for an early-morning departure. The final few hours of data collected in the afternoon were quickly processed and the final maps (Figs. 12 and 13) were produced by 1800 hr.

The processing computers were shut down and the equipment van was packed by 2100 hr.