In 1999, a Student Conservation Associate conducted the first water sampling of 14 Lava Beds ice caves. Between 1990 and the present, eight ice cave floors have been monitored for changes in ice depths by the Cave Research Foundation. In 1999, the ice in Merrill Ice Cave, one of the larger ice resources in the monument, began to melt with the formation of a hole in the center of the ice floor (Figure 6). By 2001, the entire ice resource had practically disappeared. It is paramount that an ice/water quality baseline be established before possible future losses occur in other caves.
The Glass Mountain Known Geothermal Resource Area (KGRA) is located adjacent to Lava Beds to the south. The KGRA allows the Bureau of Land Management to conduct competitive lease sales for geothermal exploration. In the past there has been exploratory drilling for geothermal resources in the Medicine Lake area up to the southern boundary of the monument. Although it is unlikely that any wells will be drilled in the monument, outside activity could have an impact on Lava Beds. There could be a drawdown of the groundwater table in addition to the vibration and disturbance caused by the drilling rigs and support activities.
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| Figure 6: Merrill Cave Ice Floor in (a) 1990 and (b) 1999, Lava Beds National Monument |
Horizon Report
A Horizon Report (NPS-WRD 1999b) is available for Lava Beds at: (http://nrdata.nps.gov/LABE/nrdata/water/baseline wq/docs/LABEWQAA.pdf). Data were collected for 131 water quality parameters (pages 40-41 of the report) from 23 sampling stations (page 39 of the report), 1966 through 1992. The stations were outside of the park unit boundary and associated with Tule Lake. The U.S. Geological Survey and the National Park Service were responsible for the water quality sampling summarized in this report.
Ice and Water Resource Monitoring
1) Ice cave studies
2) Groundwater study
3) Water quality inventory within ice caves (KLMN-FY05, Chris Currens, USGS WERC). Beginning in 2005, water sampling at Lava Beds will occur in 12 of the 28 known ice caves. Sampling will occur in caves identified as primary ice resources for the monument. The selection of caves will also be based on ease of access, technician safety, and cave resource sensitivity
4) Ice levels in eight ice caves have been monitored since 1990 by Cave Research Foundation
5) Ice cave geomorphology
6) Effects of geothermal exploration and development
7) Assess effects of adjacent land use practices on park unit resources (agricultural use, insecticides/pesticides; accumulation within Tule Lake; Tule Lake NWR management/land use)
Resource Management Water Quality Concerns
1) Loss of ice in permanent ice caves and water in seasonal wet caves
2) Lack of data on groundwater supply and possible drawdown effects
3) Lack of basic water quality inventory of intermittent-ephemeral ponds
See Attachment I for LABE water quality inventory, monitoring, and research study references.
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