HR: 17:15h
AN: H34B-06    [Abstracts]
TI: The Physical and Chemical Effects of Mid-winter Water Removal from Alaskan North Slope Lakes
AU: * Lilly, M R
EM: mlilly@gwscientific.com
AF: GW Scientific, P.O. Box 81538, Fairbanks, AK 99708
AU: Youcha, E K
EM: eyoucha@gwscientific.com
AF: GW Scientific, P.O. Box 81538, Fairbanks, AK 99708
AU: Griffith, L
EM: lgriffeth@gwscientific.com
AF: GW Scientific, P.O. Box 81538, Fairbanks, AK 99708
AU: Hinzman, L D
EM: ffldh@uaf.edu
AF: University of Alaska Fairbanks, Water and Environmental Research Center, Fairbanks, AK 99775
AU: Miller, D D
EM: ftdpm@uaf.edu
AF: University of Alaska Fairbanks, Water and Environmental Research Center, Fairbanks, AK 99775
AU: Galloway, B K
EM: ftbkg@uaf.edu
AF: University of Alaska Fairbanks, Water and Environmental Research Center, Fairbanks, AK 99775
AU: Kane, D L
EM: ffdlk@uaf.edu
AF: University of Alaska Fairbanks, Water and Environmental Research Center, Fairbanks, AK 99775
AB: For many years, the oil industry and support services have withdrawn water from freshwater lakes to build ice roads and pads for increased access to remote sites with decreased maintenance costs. This technique is quite important to the oil industry in that it allows oil field development or maintenance while avoiding the environmental disturbance associated with construction of gravel roads and pads. Construction on ice-roads and pads begins in December or January when the tundra mat is adequately frozen to support construction traffic and continues through April (depending upon weather). Recently numerous questions have been raised regarding the potential environmental consequences of water withdrawal. Possible effects of pumping include impacts to the water balance, direct impacts to aquatic organisms (including fish and invertebrates), and impacts to the pond water chemistry (with subsequent effects on aquatic creatures). There may also be associated cumulative impacts as ponds are repeatedly pumped year after year. Questions have also been raised on pumping ponds and the consequent effects on neighboring (and potentially connected) unfrozen zones within frozen rivers that serve as over-winter fish habitat. This study includes continuous monitoring of water characteristics in selected lakes in the Kuparuk and Alpine Oilfields near Prudhoe Bay, Alaska. Lakes that may be affected by pumping activities were identified and monitored to permit evaluation of the factors that impact biological populations and chemical concentrations. The measurements collected during the first winter (2002-2003) did not provide ample evidence to make any conclusive statements regarding the potential effects of water removal from these tundra lakes. A relatively small volume of water was pumped from Kuparuk lakes K209 and K214 in December, January and February, but not enough to definitely state that greater water removal will not cause some measurable impact. Year two saw substantially more water removed from several lakes, one of which (K209) was pumped to its physical limits. Remote instrumentation are capable of detecting changes in volume (when normalized for snow loads) but have not displayed an unequivocal effect of pumping (i.e. measurable difference between pumped and non-pumped lakes). We have demonstrated the ability of monitoring lakes remotely utilizing electronic sensors and radio telemetry. We established and refined techniques to collect water samples that were representative of the lakes and generally have low variation among samples within the Kuparuk and Alpine fields. We have observed variation in basic water quality parameters such as alkalinity and conductivity at the Alpine lakes as compared to Kuparuk lakes. We documented the baseline chemistry concentrations and physical parameters in these tundra lakes. We have observed the variation in ice thickness within and among lakes and have related this variation to surface snow thickness and have validated models for estimating ice thickness. This background information will be valuable for use in characterizing changes that may be observed in the upcoming winter sampling series.
UR: http://www.uaf.edu/water/projects/NorthSlope/lake_recharge/
DE: 9315 Arctic region
DE: 1823 Frozen ground
DE: 1836 Hydrologic budget (1655)
DE: 1884 Water supply
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting