Pollutant concentration in runoff at McMurdo Station, Antarctica

Abstract

The plan to modernize McMurdo Station involves constructing large buildings for more efficient facilities and infrastructure. Foundation design for these large buildings will require understanding of the mechanical properties of the native soil. This study is the first that we are aware of to conduct uniaxial compression tests on materials from McMurdo Station in their frozen state. The testing used in this study emulates specific ground conditions measured on-site. Reconstituted specimens of well-graded gravel basalt were compacted at 4% and 20% by weight moisture contents and frozen at temperatures of −7°C and −20°C. Test results determined that higher moisture content combined with lower ambient temperatures resulted in increased strengths compared to optimum moisture and compaction testing results. If new building foundations will be in direct contact with the ground and allow heat transfer to take place, then the base material should be placed and compacted at the optimum moisture content. This will reduce the potential effects of thaw degradation under the foundation, especially on icerich ground. DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents.

Assessment for soil reuse standards at McMurdo Station

“…Some of the natural runoff flow paths change over time due to erosion, which depends on the intensity of the snowmelt runoff. A study done by Affleck et al (2014) showed flow discharge during the austral summer ranges from 74 to 4239 m 3 /day, indicating runoff does occur at the Station. Consideration for the hydrological flow paths established at the site is important for understanding soil reuse standards and guidelines.…”

“…Because of the slow biological degradation of the legacy pollutants within polar environments, the contaminants persist, frozen in place, and accumulate, lasting indefinitely. Contaminants related to the above disturbances (hydrocarbons and metals) were specifically found to be elevated in runoff during the snowmelt period (Affleck et al 2014). Kennicutt et al (2010) and Klein et al (2008Klein et al ( , 2012 collected and analyzed several hundred soil samples over nine years to monitor the extent of the environmental impact of the various contaminants.…”

“…The finegrained materials exist due to the physical and natural (thermal and cryogenical) changes with time. The presence of ice-cemented permafrost within Ross Island is common (Balks et al 2013;Affleck et al 2017Affleck et al , 2014Affleck et al , 2012. The presence of reddish material is common throughout the Station and is composed of a sand and gravel mixture (Crockett 1998).…”

“…The major flow paths at the Station are well defined, with earthen ditches that cross under roads via culverts (Affleck et al 2014). Ditches are relatively deeper than other natural flow paths.…”

Ground-penetrating radar studies of permafrost, periglacial, and near-surface geology at McMurdo Station, Antarctica

“…However, moraines, permafrost polygons, massive ice wedges, and other shallow geomorphology features are still visible at the station borders, suggesting their prior existence also on station grounds. Secondary impacts from McMurdo activities include increased airborne dust from vehicle traffic, which has altered snowpack albedo; associated melt water runoff from local snowfields; a deepening of the active layer or complete thawing of permafrost; and increased stream flow and erosion (Campbell et al, 1994;Klein et al, 2008aKlein et al, , 2008bAffleck et al, 2012Affleck et al, , 2014aAffleck et al, , 2014band Affleck and Carr, 2015). Accidental or historical human activity, such as chemical spills, fuel leaks, garbage and construction debris burial, is also prevalent at McMurdo Station, resulting in increased subsurface complexity relative to other similar near-surface geology study sites.…”