National Science Foundation
Office of Polar Programs
Arlington, Virginia

Continued Implementation of Hydrologic Investigations
In the Dry Valleys, Antarctica - Project S-024

Finding of No Significant and Not More Than
Minor or Transitory Environmental Impact

The National Science Foundation (NSF) has prepared an Initial Environmental Evaluation (IEE) and an Environmental Assessment (EA) as a combined environmental document, for continuation of hydrologic investigations during the 1993-1994 field season in the Dry Valleys, Antarctica. Activities include maintenance of stream gauging stations, stream tracer experiments, relic channel reactivation, construction of a temporary equipment hut, and use of two snowmobiles on frozen lake surfaces. Based on the analyses in the environmental document (IEE/EA), the NSF Office of Polar Programs (OPP) has determined that implementation of Alternative C is not a major federal action which would have a significant effect on the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. The action is not one which would have more than a minor or transitory effect on the antarctic environment, within the meaning of the NSF's implementing regulations for the Protocol on Environmental Protection to the Antarctic Treaty. Therefore, an environmental impact statement and/or a comprehensive environmental evaluation will not be prepared.

The selected alternative, C, provides for the continuation of hydrologic investigations in the Dry Valleys. In addition, specific monitoring criteria are established to assist in the evaluation of the environmental effects of field operations. This alternative is consistent with NSF's efforts to promote scientific investigations while improving protection of the antarctic environment.

S/Dr. Cornelius W. SullivanNovember 17, 1994

Dr. Cornelius W. Sullivan
Director
Office of Polar Programs
National Science Foundation
4201 Wilson Boulevard
Arlington, Virginia 22230


National Science Foundation
Office of Polar Programs
Arlington, Virginia

Continued Implementation of Hydrologic Investigations
In the Dry Valleys, Antarctica - Project S-024

November 17, 1994

Environmental Assessment
Initial Environmental Evaluation

I. PURPOSE AND NEED FOR THE PROPOSED ACTION

The NSF proposes to continue the support of research involving the collection of hydrologic information in association with the McMurdo Long-Term Ecological Research (MCMLTER) project now underway in the Dry Valleys, Antarctica. In addition, NSF proposes to initiate supplementary monitoring and evaluation of the possible environmental consequences of data collection and ancillary field activities.

Questions have been raised regarding the environmental impact of these hydrologic investigations and it is the intent of NSF to determine if ongoing practices should be terminated, revised, or mitigated through additional environmental protection and/or remediation measures.

The collection of hydrologic data by a field party of six from mid November 1994 through February 1995 is to provide invaluable information for the conduct of the MCMLTER in Antarctica. The project is part of a 10-year or more study of ecosystem dynamics conducted at 18 locations in the Western Hemisphere. The following describes the type of data collected and location of sampling points in the Dry Valleys, Antarctica.

A. Stream gauging

Stream gauging includes collection of data on stream discharge and ancillary measurements, temperature and electrical conductivity at a total of 27 locations in the Dry Valleys. These data are necessary for fulfillment of many of the scientific objectives of the MCMLTER.

The stream gauging network is established as described in Attachment A. The network is composed of 14 stations employing content Parshall flumes and overflow weirs, stations using natural channel controls, and 13 other stream sites where only periodic measurements are made. The stations at the Lake Fryxell basin were constructed in 1990-1991 as part of the research activities of the S-008 Biogeochemistry of Dry Valleys Lakes project (Attachment B).

During the 1993-1994 season, the Parshall flume/weir site on Green Creek, constructed for the S-008 project, was removed, and a new station was established upstream. The Green Creek station was moved because Lake Fryxell has risen about one meter, partially submerging the Parshall flume. The removal was easily completed by emptying the natural alluvium sandbags which were positioned adjacent to the stream. The previously disturbed area was raked to establish an upper layer of small rocks in a small (0.5 to 3 cm) surface zone. Sandbags were removed from the area.

A few additional natural channel control gauging stations are anticipated to be needed for periodic measurements. Knowledge of stream flows and rates of lake level rise is useful in the identification and avoidance of potential sampling or support sites which could become submerged by rising lake levels.

A stream gauging network in Taylor Valley of the Dry Valleys was included as a critical data set for the MCMLTER. The streams are a major ecosystem type in their own right, and are also a major linkage between the glaciers and the soil and lake ecosystem. The continued lake level rise in Taylor Valley necessitates quantitative measurements of stream discharge to the lakes. Expansion of the stream gauging network of Lake Hoare and Lake Bonney was carried out during the first field season of the MCMLTER.

The network includes a site on Canada Stream within the Site of Special Scientific Interest (SSSI) No. 12. This gauging station was permitted under the regulations for the Antarctic Conservation Act of 1978 by the NSF/OPP Permit Office prior to its installation (Attachment C). The gauging station is located on the site of a rock weir installed by the New Zealand Antarctic Programme (NZAP) before the site was designated as a SSSI. The weir was washed out with only remnants now remaining. The NZAP scientists conducting research within the SSSI were consulted in the permit application process.

B. Relic Stream Channel Reactivation

To quantify recolonization processes for algae and mosses in Dry Valleys streams and complement ongoing hydrologic data collection, a long-term experiment is proposed to reactivate existing relic stream channels beginning in the 1994-1995 field season. At the junction where the west and east channels of upper Von Guerard stream diverge (Attachment D), sufficient water to sustain surface flow would be routed down the channels by redistributing sediment and positioning alluvial-filled sandbags to form a diversion.

The stream flow has been increasing in the McMurdo Dry Valleys due to a sustained warming trend and increased glacial meltwater. The increase in stream flow is expected to cause geomorphological changes in stream networks and stream ecosystems. Observation of the distribution of algae and mosses in the streams suggests that hydrologic conditions have a major control on stream biota. The long-term relic channel reactivation experiment in Von Guerard Stream is to obtain a more quantitative, process-level understanding of the distribution of biota. This experiment, in the addendum to the MCMLTER proposal, was accepted by the Long-Term Ecological Research (LTER) review panel and is a critical component of the stream ecology studies. Further, the streams are the main linkages between the glaciers and soil and lake ecosystems, and therefore, understanding the long-term ecological processes in the streams is important to the overall objectives of the MCMLTER. Comparable recolonization experiments are being conducted at other LTER sites in the network. For example, in the Kubarik River in the Toolik Lake, Alaska LTER, the stream bed has been colonized by a moss during an ongoing (12-year) nutrient enrichment experiment.

There are 10 major streams flowing into Lake Fryxell, all having comparable peak flows (flows with peaks that vary by a factor of two or less). The comparable peak flows of Lake Fryxell streams contrasts with the peak flows of streams contributing to other lakes in Taylor Valley. In the Lake Bonney and Lake Hoare/Chad basin, the stream flow input there is widely distributed among many streams, peak flows vary extensively. It is advantageous to conduct the relic channel experiment in the Lake Fryxell Basin to reduce the influence of a human-altered peak flow among contributing streams to a lake. The reactivation of a relic channel contributing to Lake Fryxell will mimic natural stream input and minimize the potential impact on a lake from reactivation of a relic stream channel.

The upper reach of Von Guerard Stream was chosen as the site within the Lake Fryxell Basin because:

C. Stream Tracer Experiments

Tracer experiments with naturally-occurring, dissolved constituents in streams in Taylor Valley, Antarctica are used to gain a mechanistic understanding of hydrologic and biogeochemical controls on dissolved constituent transport, uptake, and biological transformations of nutrients. These experiments are necessary to meet the scientific objectives of the McMurdo Dry Valleys Long Term Ecological Research project (MCMLTER).

Due to a sustained warming trend, stream flow in the McMurdo Dry Valleys has increased, and the lake levels in the valley bottoms have steadily risen (Chinn, 1993 in Attachment E). The streams cut through unstable, barren alluvium underlain by permafrost before reaching the lakes. The streams in the Dry Valleys are the main links between the glaciers, the prime source of water, and the lakes. These streams contain, to varying degrees, algal mats and mosses that become photosynthetically active as soon as water begins to flow in the austral summer. Biological uptake and transformations can, therefore, be important in regulating the flux of dissolved constituents to the lakes. To understand the response of the streams and lakes to increased discharge, it is important to gain more quantitative knowledge of the transport and transformations of dissolved constituents in the streams.

The use of chemical tracers, such as dyes, is a standard and successful method to quantify hydrologic processes. Only one stream tracer study has been conducted in the McMurdo Dry Valleys. This study involved conservative (non-reactive) dissolved constituents (lithium, chloride, and bromide) that are present naturally in the stream water from dissolution of marine aerosols (wind blown sea salt) and from rock weathering. This tracer study was conducted in Huey Creek, a relatively steep gradient stream, with very sparse algal mats. It is not desirable scientifically to apply the hydrologic parameters determined in the one study to other streams in the Dry Valleys. It is necessary to conduct additional tracer studies in streams with lower gradients (less steep) and with more abundant biota in order to determine how hydrologic parameters vary with gradient, volume of stream flow, and biota. Stream tracer experiments have been conducted at other LTER sites (i.e., the Coweeta LTER in North Carolina) and the hydrologic parameters can be compared.

One of the five core areas of the overall LTER program focuses on transport and transformation of nutrients (nitrogen and phosphorus) within the ecosystem. For the Dry Valleys lakes, the nutrients in the streams are the only nutrient sources. In order to understand processes controlling nutrients in the streams, experiments using brief nutrient enrichments were proposed in the addendum to the MCMLTER proposal, and are critical for addressing this core area objective for the MCMLTER. Comparable nutrient tracer experiments have been conducted in the Kubarik River for twelve years as part of the Toolik Lake, Alaska LTER, and in Lookout Creek for three years in the H.J. Andrews, Oregon LTER.

Attachment F contains the proposal submitted in 1991 for the stream tracer experiment in the Taylor Valley. This experiment was reviewed by the NSF Environmental Officer. The proposal presents calculations which show that the quantities of tracer constituents added for the brief period (three hours) of that experiment are a small fraction of the total quantity carried by that one stream during the period of glacial melt water flow, and are several orders of magnitude below the total quantities in the receiving lake. The tracer studies during the 1994-1995 austral summer would add tracer constituents for a few hours up to 48 hours (see environmental effects and mitigating measures, below).

D. Ancillary Actions--Snowmobile Use and Placement of a Temporary Supply Hut

1. Snowmobile Use

Since the 1990-1991 season, two snowmobiles have been used for transportation on Taylor Valley lakes to conduct hydrologic data collection. During the 1994-1995 austral summer season, one snowmobile at Lake Fryxell and one at Lake Bonney would be required to transport personnel and equipment to and from the main camps at Lakes Fryxell and Bonney to the stream sampling sites. Much of the sampling equipment is heavy and bulky making overland on-foot transportation arduous and time-consuming. In addition, during brief stream flow events, it is often necessary to visit several sites within a short time, an almost impossible task without the use of a snowmobile. Snowmobiles are typically used to support scientific research in the field (SEIS-1991). However, because of the special nature of the Dry Valleys, among the most extreme deserts in the world, snowmobile use must be carefully planned and controlled to avoid damage to the fragile ecosystem - the subject of study by MCMLTER. The surface of the lake ice is irregular, therefore the snowmobiles are used only on the moat ice along the lake shore. This makes them useful for access to the stream gauges which are located at the outlets of the streams entering the lakes. The snowmobiles are used until about mid December when the ice begins to melt and moats form.

2. Placement of a Temporary Supply Hut

An equipment hut is needed to support the hydrologic investigations. A study stream, Von Guerard, is located on the south shore near the east end of Lake Fryxell. The existing camp is approximately six kilometers by foot away from the mouth of the stream. Until mid December, personnel would travel to and from the site by snowmobile. From mid December through early February, after the moat forms, investigators would walk around the lake. By providing a shelter, investigators would be able to filter stream water samples and stage and repair scientific equipment in an environment protected from the weather, as well as eliminate the need to repeatedly travel to and from the site and the main camp to perform these activities. The hut, supplied with a 208-liter fuel drum and stove, would also be used for preparing food while investigators are at the site. It would not be used for sleeping.

E. Issues Related to the Proposed Action

Issues related to data acquisition for stream flow gauging, relic channel reactivation, and stream tracer experiments are:

Stream flow gauging

Relic channel reactivation

Stream tracer experiments

Issues associated with snowmobile use and placement and use of a temporary supply hut are:

Snowmobile use

Temporary supply hut

These issues are addressed by the alternatives under consideration and provide organization of the discussion of the environmental consequences of alternatives in section III, environmental effects and mitigating measures.

II. ALTERNATIVES

Alternatives were developed to address the issues identified above.

  1. Alternative A
  2. Alternative A would continue the ongoing data collection in the Dry Valleys without any provisions for increased monitoring and evaluation during the 1994-1995 field season.

  3. Alternative B
  4. In this alternative, the ongoing data collection would be terminated with the removal of all sampling equipment. No additional hydrologic data would be collected in the Dry Valleys associated with the MCMLTER. This alternative was developed to evaluate the environmental effects of ceasing all operations while natural processes recover from the effects of human activities at the study sites.

  5. Alternative C
  6. Alternative C continues data collection for one year and requires the monitoring of field activities such that at the conclusion of the field season the following will be recorded:

At the conclusion of the field season, results would be evaluated and projects would be continued or modified based upon the results of field evaluations of environmental effects. It is recognized that termination of ongoing data collection could have serious effects on the ultimate usefulness of data interpretations and research results and that all sampling equipment would be removed as in Alternative B. Continuation of field sampling for the 1995-1996 austral summer and beyond would require additional environmental review and decision by the responsible federal official.

III. ENVIRONMENTAL EFFECTS AND MITIGATING MEASURES

The environmental effects of each alternative are described below for each of the major activities in each of the three alternatives, A, B, and C, as they relate to the issues described in section I. The environmental effects refer to Alternatives A and C unless otherwise specified. Mitigating measures to reduce the possible impacts to the antarctic environment and dependent and associated ecosystems are described as appropriate.

A. Stream gauging.

1. Chemical contamination of stream water

The Dry Valleys streams which flow intermittently have very dilute chemical makeup showing no apparent indicators of human alteration. The existing gauges are constructed of inert materials (polyester and fiberglass) and stream channel alluvium. This design minimizes possible chemical contamination from leaching of introduced materials as would be possible with concrete-supported instrumentation. There would be no substantive difference in the effects of Alternatives A, B, and C with respect to the potential chemical contamination of stream water from gauging instrumentation or field equipment.

2. Deposition and transport of sediment

The existing 27 gauging stations in the network consist of 14 Parshall flumes with weirs suitable for high flow measurements and 13 natural channel control stations and sites (Attachment E, Table 1). Parshall flumes and natural channel control reaches do not retain sediment in the channel, as would a V-notch or other weir that creates a backwater pool. Therefore, the natural sediment transport regime of the sample Dry Valleys streams would be maintained. Sediment transport and deposition can be substantial during high flow for study streams, with up to six centimeters of material being deposited in delta areas in a few days. If the gauging stations with flumes and weirs are removed as in Alternative B, the channel in that short stream reach would return to its former, natural condition in one or two austral summers. At the natural channel control stations, the only materials in the streams are plastic tubing and a few probes attached to a metal rod. At these sites, a few rocks have been moved within the channel. Other minor disturbances may occur to the stream bed when periodic, discrete, stream flow measurements are taken using a flow meter such as a Pygmy meter. Each of these disturbances are expected to cause no long-term damage to the stream system. Channel materials are expected to establish natural distributions within one or two austral summers after the conclusion of sampling.

If the rising lake level encroaches on one or more gauging stations, the station(s) will be removed and placed at a higher location if possible in Alternatives A and C. If another suitable location on the stream cannot be found, another stream would be gauged to continue the study. The effects of moving a station are similar to that of removal. However, a relocated flume/weir station, will cause another disturbance to a stream channel when it, too, is removed at the conclusion of the study.

3. Data quality

In order to justify the field effort involved in the gauging network, it is critical to have at least two gauging sites in each lake basin that provide high quality data at low flow conditions. Such sites involve the Parshall flume and weir approach described in Attachment A. Hydrologic budgets for the lakes can then be computed using inter-correlations between streams. Alternative B would not allow this data collection to continue, negating the value of past records for interpretation. Alternative A would allow the collection of accurate data of sufficient duration to provide needed forecasts of information. Alternative C would provide the same level of detail only if it were continued beyond the 1994-1995 field season, a provision which is not in Alternative C.

4. Short-term effects

The short-term effects are minor because there is minimal effect on stream flow and sediment transport. The disturbance to the stream bed at the stream site of the flume/weir stations is highly localized and transitory. In the natural channel control stations, there is minimal effect, even in the immediate vicinity.

5. Long-term and cumulative effects

The operation of the stream gauging network will have no long-term or cumulative effects. If the lakes continue to rise, the gauges will be removed before becoming submerged.

B. Relic Channel Reactivation

1. Contamination of stream water

Stream water is very dilute in major salts. Any chemical contaminates in the stream water would be introduced into Lake Fryxell. For this reason, the barrier to redirect stream flow to the relic channel will be constructed from channel sediments. The only introduced materials are the polyester sandbags which are inert and will not be a source of dissolved constituents. These sandbags will be removed at the conclusion of sampling in each alternative.

2. Construction and maintenance of flow redistribution at the point of divergence

The initial construction of the barrier can be accomplished in a short time (about one week) by several people based at a small camp at the site of the equipment hut at the outlet of Von Guerard Stream to Lake Fryxell. The camp would consist of tents. All waste produced at the site, including human, would be contained and retrograded to McMurdo Station. At the conclusion of barrier construction, the tents would be removed and the remaining field work would be conducted from the equipment hut. Any disturbances due to setting up the camp, such as moving rocks for placing the tents, would be corrected by returning rocks to near original locations and smoothing the soil surface to eliminate any apparent disturbance.

In Alternative A, the barrier would be maintained during the overall LTER stream flow monitoring program for Taylor Valley. The ecologists following the development of algal mats and mosses in the relic channels would conduct these studies as part of other ecological studies. Therefore, this experiment would not require a large increase in field personnel for the MCMLTER. In Alternative C, the barrier would be maintained only if data collection were continued after additional review at the end of the 1994-1995 field season. No barrier would be constructed in Alternative B.

3. Short-term effects

The short-term effects will be the intervention of the natural flow of the channels. It may be speculated that this would eventually happen as sediments are deposited in one channel redirecting the flow of the water to the other, relic channel, and that the proposed action only accelerates this process.

4. Long-term and cumulative effects

Given the dynamic nature of the streams in the Dry Valleys, and the substantial effect on the streams and lakes caused by the warming trend, no long-term effects are expected for the lake ecosystem. For the stream ecosystems in the reactivated channels, a greater biomass may accumulate over the course of the experiment than might have occurred otherwise. Again, the overall effect of the greater stream flow in the Dry Valleys is expected to be greater biomass in the stream ecosystems, and such an effect in Von Guerard Stream would be relatively minor.

C. Stream Tracer Experiments

1. Duration and frequency

Some potential environmental effects are associated with the presence of personnel in the field. Tracer experiments will typically involve intensive sampling, at 5 to 10 sites for a limited time period. For the tracer experiments, the period of tracer addition will range from several hours to at most 48 hours. The frequent sampling of the stream will continue for up to 24 hours following the completion of the tracer addition. Automatic samplers will be used to collect water samples as much as possible to minimize the number of persons in the field for the experiment. In any year, a maximum of two such tracer experiments would be conducted.

2. Stream location

The study streams are located in Taylor Valley and flow into one of the three main lakes (Fryxell, Hoare, and Bonney). There experiments and processing of samples after the experiment will be conducted at these camps. No tracer experiments will be conducted in Canada Stream, which is currently within a Site of Special Scientific Interest (SSSI No 12). Use of established camps will minimize environmental impact associated with the number of personnel in the field by reducing the travel required among sample sites.

3. Selection of tracer constituents

Only dissolved constituents naturally present in the streams will be used for the experiments. A solution containing a conservative tracer (LiCl) and the nutrients nitrate and phosphate will be added to a well within the hyporheic zone (alluvium in the stream bed). At the same time another tracer (NaCl) will be injected in the stream channel itself, to provide an accurate measurement of flow. Investigators will then follow the transport and biological uptake of the nutrients with respect to the tracers as they are exchanged in the stream channel. Detailed measurements of natural concentrations will be made for at least one field season prior to the experiment. In Alternative C, only detailed measurements of natural constituents would be conducted. The tracer experiment will be designed such that the total quantity of tracer added is less than 25% of calculated total quantity carried by the stream during the austral summer. Because there are several streams flowing into the study lakes, the increased concentration of natural tracer is only a small fraction of the total dissolved constituents entering the lake from all sources.

4. Short-term effects

Short-term effects will consist of footprints near the stream sampling sites and brief changes in the concentration of naturally occurring dissolved constituents. For some constituents, the concentrations vary as much as five-fold during the austral summer and also during the day. The concentration of NaCl added to study streams is not expected to impact the stream biota in that tracers would be added as short-term alternations below expected threshold levels of disturbance to biota.

5. Long-term and cumulative effects

In Alternative A, no negative or long-term effects are expected because the quantity of tracer used will be insignificant compared to the average total input to the receiving lakes for all the inflow streams. No other tracer experiments are known to be planned by USAP or any other national antarctic program working in the Dry Valleys, Antarctica.

Implementation of Alternative C with no additional stream tracer studies in following years, would negate the value of the 1994-1995 field data in that more than one season of data collection is required to provide meaningful results.

D. Snowmobile Use on Frozen Lakes

1. Use of fuel and lubricants

In Alternatives A and C, snowmobiles would be used to transport personnel and equipment on the frozen lakes. This requires the use of fossil fuel and lubricants. Alternative B requires no fossil fuels or lubricants.

Strict controls for the use of snowmobiles will be implemented to prevent contamination from any spilled fuels or lubricants. Snowmobiles will not be allowed to drip fuel or lubricants onto snow or ice when parked. Operators will be instructed on the safe transport and use of fuel and oil. The operators will be instructed, and responsible for, cleaning up any fuel spilled in the area. Materials to respond to and clean up fuel spills will be part of the project's field supplies and will be provided by the civilian contractor. To reduce noise pollution, the civilian contractor will ensure the factory-installed mufflers are inspected and found to be functioning properly prior to issuance of the snowmobile to the field party. The engine will also be thoroughly cleaned prior to being issued.

2. Health and safety

The investigators are trained and experienced in field safety. The operators of any motorized equipment are also trained and certified in their safe operation. Alternatives A and C offer increased health and safety protection by reducing the amount of time investigators spend traversing to their field sites and the chances of injuries due to overexposure. The use of snowmobiles is restricted to frozen lake surfaces and a condition of approved operating procedures for the 1994-1995 project S-024. Ice conditions will be evaluated prior to use. Crew members are trained in proper safety procedures when travelling over ice surfaces during thawing conditions.

3. Economics

Use of a snowmobile provides much more efficient use of personnel resources and affords an opportunity to increase the productivity of crew members during their brief field season. In addition, it may allow the overall reduction in the number of personnel required to conduct the studies, a net decrease in costs.

4. Aesthetics

Snowmobile use is restricted to the surface of the frozen lakes. Operation of the vehicles on the surrounding terrain is strictly prohibited. The field site will be visited by one or more ACA Enforcement Officers in January and/or February to evaluate compliance with conditions of all permits and adherence to mitigation measures described in this environmental document. Any evidence of snowmobile use on the surrounding terrain or failure to implement mitigating measures would require remedial action to repair any damage. In addition, NSF would implement penalties if warranted.

5. Short-term effects

Alternatives A and C will cause a temporary increase in exhaust emissions and noise while vehicles are being used. Alternative B would avoid this impact.

6. Long-term and cumulative effects

As long as the restricted use, fuel handling, and vehicle storage requirements are followed, there would be no long-term effects on the unique antarctic ecosystem of the Dry Valleys. If vehicles were used on the fragile terrain, the soil surface could be disturbed resulting in a potential increase in erosion and disruption of soil forming processes. Such use of USAP equipment serves no legitimate scientific need and would be viewed as irresponsible destruction of the fragile Dry Valleys ecosystem. No other projects or national programs are expected to use snowmobiles on the two lakes identified in the 1994-1995 project S-024.

E. Placement of a Temporary Hut

1. Health and safety

The structure with a stove will aid investigators at the site. They will be able to prepare samples and maintain scientific equipment while being protected from the weather. This reduces the potential for exposure-related injuries. The structure would provide emergency shelter in the event of a personal injury or weather emergency.

2. Waste Management

The hut will be constructed using prefabricated, modular panels which eliminate construction debris. Any waste, including sanitary wastes, generated at the site during its use would be strictly managed to prevent any release to the environment. Waste containers will be provided. All wastes will be returned to the main camp to be returned to McMurdo Station for processing and/or disposal. By having a structure to store supplies and prepare samples, the chances of materials becoming windblown during would be significantly reduced.

3. Spill Containment

A 208-liter fuel drum would be placed at the site for the gas stove. It will be placed over a drip pan; the same as those used at all camp sites in the Dry Valleys. The hut will also serve as a form of containment. Should samples or standard solutions be spilled in the hut, they would spill onto floor where they could be quickly cleaned up, eliminating a release to the environment.

4. Short-term Effects

The placement of the hut will have little environmental effect. The hut will be anchored to secure it from high winds. The hut will be installed with the expectation that it would remain over winter. Because the hut will sit on runners and be slightly elevated, there will be no need to clear the area of rocks. Depending upon the results of environmental evaluations in Alternative C, it may be necessary to remove the hut or install additional mitigating measures during the 1995-1996 austral summer following appropriate environmental review.

Some short-term disturbances will be realized as a result of those using the hut, namely paths created by foot traffic to and from the hut and from the placement of the anchors. These should disappear over time after the investigations are completed, within five to eight years. The hut will be disassembled when it is no longer needed, the panels placed on a pallet, and moved along with the stove and fuel drum to one of the main camps to be stored, or returned to McMurdo Station.

F. Summary of the Environmental Effects of All Activities

1. Nature, Extent, Duration, and Intensity of the Likely Direct Impacts

a. Direct Environmental Impacts

Footprints will be visible in the vicinity of the gauging and sampling stations. Foot traffic would be contained by establishing trails, however, there is unavoidable disturbance to the upper layer of the soil, on the trails and in the immediate vicinity of any tents and the hut. The temporary hut would be visible for the duration of the hydrologic sampling program. Two snowmobiles would be seen and could be heard during their use in late November and December.

There will be disturbances to the stream bed at the flume/weir sites. The stream bed is altered in the immediate vicinity of the flume and cut-off wall. To obtain high quality data during low flow conditions, this effect is unavoidable. The impact would remain for an estimated one to two years after the flume and cut-off wall are removed at the conclusion of field data collection.

Some alteration of stream flow conditions will occur in Von Guerard Stream. The relic channel will begin redistribution of sediments as the stream flow regime is reactivated. This is an unavoidable impact, but one that mimics natural stream morphology in the Dry Valleys. This effect on the channel will persist while the control site is maintained. At the conclusion of the experiment, the stream channel would continue to evolve through natural processes.

b. Impacts on Scientific Research

The proposed activities will greatly increase the knowledge of the hydrology and ecology of glacial meltwater streams in the Dry Valleys. This scientific knowledge will be of value to many other fields of research conducted in the Dry Valleys, such as geology, soil ecology, geochemistry, and paleolimnology. Further, these databases and understanding of ecological processes in the streams are critical for success of the MCMLTER. The results will be used to understand linkages between the glaciers and soil and lake ecosystems. Finally, because the MCMLTER is an active participant in an on-going LTER inter-site comparison on carbon transport and cycling in stream ecosystems, the results will directly enhance knowledge of climatic factors and landscape processes which cause variance among stream ecosystems.

In addition to enhancing fundamental scientific knowledge, the results will have a direct benefit to other scientific projects in the Dry Valleys, such as those concerned with estimating the future rate of change of lake levels.

c. Impacts on Other Existing Uses and Values

To some observers, the scientific investigations may appear to be permanently impacting the local environment. For example, the flume and weir gauging stations and the accompanying wing-wall dams appear to be permanent alternations of the stream environment. To inform people about the observed rapid recovery rates of Dry Valley streams, on-site investigators and NSF personnel will be alerted to the need to accurately describe the short- and long-term effects of the hydrologic investigations in the Dry Valleys.

2. Indirect or Second Order Impacts

The proposed activities require a field crew of six people which must be supported through McMurdo Station in addition to necessary transportation to Antarctica and to the Dry Valleys. While in transit, food, shelter, and transportation is required. The impacts of these services are not long-lasting or unusual in the vicinity of McMurdo Station or Dry Valleys.

Because of the rapid recovery rates of the stream channels and the limitations on the amounts of natural constituents that would be added as stream tracers, no secondary or indirect impacts from the hydrologic investigation is anticipated. However, an accident with a snowmobile or a fuel spill from the 208-liter drum, could produce localized contamination of ice, soil, or sediment. Spill clean-up would remove contaminated material to McMurdo Station for recycling or removal from Antarctica. Some contaminated materials, however, may not be collectable and would remain in the Dry Valleys if an accident occurred.

3. Irreversible or Irretrievable Commitment of Resources

The consumption of fossil fuel is an irretrievable and irreversible use of a natural resource in the conduct of the project. However, the fossil fuels consumed are minor and consistent with other similar investigations conducted in the past. Approximately 29 hours of helicopter flight time will be required. Fuel use at the site, one 208-liter drum and fuel use by snowmobiles, seven to eight liters per hour of use, is minor. Alternatives A and C would consume similar amounts of fuel in the 1994-1995 season while Alternative B would reduce fuel use to that required to remove any field equipment and remediation or all sample sites. The materials used in the project are minor commitments of resources.

4. Short-term Uses of the Environment and the Maintenance and Enhancement of Long-term Productivity

The short-term uses of the landscape for the stream gauging network are highly localized and do not have an impact on the long-term productivity of the streams. The relic channel reactivation experiment is expected to enhance the biologic productivity of the streams where flow has been reactivated. Conversely, in the channel where flow has been diverted, biologic productivity is expected to decrease. However, none of the activities in the project will affect the long-term productivity of the ecosystems in the Dry Valleys.

5. Possible Conflicts in Land Use, Policy, and Research

There are no known conflicts with the hydrologic data collection project in Alternatives A and C and other ongoing or anticipated projects in the Dry Valleys. While the projects are underway, the sites may not be available for other research projects. However, depending upon the nature and scope of other investigations, appropriate accommodation may be possible.

The hydrologic data collection project is consistent with the Protocol on Environmental Protection to the Antarctic Treaty, applicable permitting procedures of the ACA, and environmental review regulations and procedures of NSF. In addition, the project is consistent with United States policy to protect the relatively unspoiled environment of Antarctica and its dependent and associated ecosystems while preserving and pursuing unique opportunities for scientific research to understand Antarctica and global physical and environmental systems.

6. Methods and Data Used to Forecast the Impacts of the Proposed Activity

The methods used to forecast impacts are based on direct observation and several years of experience in the conduct of field projects in the Dry Valleys and elsewhere in Antarctica. Specific knowledge of water chemistry and stream hydrology and geomorphology were used to estimate the impacts of the proposed actions.

7. Gaps in Knowledge and Uncertainties

As described in Alternative C, additional information will be collected regarding the performance of the hydrologic data collection project in order to better evaluate potential environmental effects and the administration of permitting procedures and enforcement processes. Anticipated environmental effects are known with sufficient reliability to anticipate successful performance of the proposed project within the estimated environmental effects. However, increased information is sought to determine if improvements can be identified and implemented.

With regard to hydrologic information, a gap in knowledge exists in stream flow records. The only long-term record of stream flow is for the Onyx River in Wright Valley of the Dry Valleys. In addition, the only multi-year record available for small meltwater streams is the three-year record for the Fryxell Basin streams. The measured lake level rise throughout the Dry Valleys is evidence of increasing stream flow over the past decades, upon which forecasting is based. Additional data is required for the MCMLTER.

8. Cumulative Impacts

In 1993, NSF funded the establishment of the MCMLTER with the collection of hydrologic data as an element of the MCMLTER project in the Dry Valleys. While the establishment of stream gauging stations may be the most noticeable activity of the MCMLTER besides the establishment of a base facility described in the environmental document (Replacement of Facilities to Support a Long-Term Ecological Research Project in The McMurdo Dry Valleys, Antarctica, November 4, 1993), the environmental effects of the entire project are not anticipated to be more than minor or transitory. With the mitigation measures in place to remove all wastes and clean up any accidental spills of fuel or any designated pollutants, potential environmental effects are minimized. At the conclusion of the hydrologic data collection each site would be reclaimed as would all of the sites in the MCMLTER. No long-term or permanent impacts are expected with the LTER or any other known projects in the area.

Besides scientific investigations, tourism has the potential to disturb stream channels and banks. Tourists hiking in the channels or along the edge of the stream banks could erode stream banks and alter sediment deposition. However, announced plans of tour operators have indicated that tourists would not stop in the Dry Valleys during two, known scheduled helicopter overflights in the 1994-1995 season.

9. Monitoring Program

Monitoring of environmental impacts while conducting scientific investigations is not typically a responsibility of the investigator, unless it forms a component of the proposed scientific study. In the case of the MCMLTER project and in Alternative C, it is appropriate to include monitoring as a part of the investigation as described in section II, Alternatives. Investigators in the field will be responsible for recording the physical changes to the antarctic environment that occur as a result of their activity. These records would include, but are not limited to, measurements of the amount of sediment deposition caused by the gauging stations and photographic records of areas affected by human activity (e.g., trails, encampments, sampling points, and huts), among others. The results of such monitoring would not only identify ways to minimize impacts in the Dry Valleys and identify improved field methods, but may also be valuable for making improvements to other antarctic scientific field studies.

IV. CONSULTATION WITH OTHERS

National Science Foundation/ Office of Polar Programs: (703)306-1031
Mr. Robert Cunningham NEPA Compliance Manager
rcunning@nsf.gov
Mr. Peter Karasik Associate Compliance Manager
pkarasik@nsf.gov
Ms. Joyce Jatko Environmental Officer
jjatko@nsf.gov
Dr. Polly Penhale Manager, Polar Biology and Medicine
ppenhale@nsf.gov
Dr. Carol Roberts Deputy Director, Office of Polar Programs
croberts@nsf.gov

Antarctic Support Associates (ASA)
(303)790-8606
Ms. Terry Johnson Environmental Manager
JOHNSOTE.ASA@asa.org
Ms. Vicki Kraus Environmental Engineer
krausvi.asa@asa.org
Dr. Steve Kottmeier Manager Lab Services
kottmest.asa@asa.org

S-024/MCMLTER
Dr. Diane McKnight USGS/Team Member
(303) 541-3015

ATTACHMENTS

Attachment A

Journal Article: Hydrologic and geochemical processes at the stream-lake interface in a permanently ice-covered lake in the McMurdo Dry Valleys, Antarctica; McKnight/Andrews

Attachment B

Abstract for S-008 project

Attachment C

Antarctic Conservation Act permit for gauging Canada Stream

Attachment D

Map of Stream Channel Reactivation Site

Attachment E

McMurdo LTER: Stream Flow Measurements in Taylor Valley

Attachment F

Letter from NSF Environmental Officer and Proposal to Study Hydrologic Processes at Lake Fryxell; McKnight/Andrews/von Guerard/Harnish


Go to: MCM Dry Valley environmental issues MCM LTER home page