Contaminants, in freezing ground or elsewhere in the world, are of concern not simply because of their presence but because of their potential for detrimental effects on human health, the biota, or other valued aspects of the environment. Understanding these effects is central to any attempt to manage or remediate contaminated land. The polar regions are different from other parts of the world, and it would be naïve to assume that the mass of information developed in temperate regions can be applied without modification to the polar regions. Despite their obvious environmental similarities, there are important differences between the Arctic and Antarctic. The landmass of the Arctic is much warmer than that of the Antarctic and as a result has a much greater diversity and abundance of flora. Because of its proximity to industrial areas in the Northern Hemisphere, the Arctic also experiences a higher input of contaminants via long-range aerial transport. In addition, the Arctic, with its indigenous population and generally undisputed territorial claims, has long been the subject of resource utilisation, including harvesting of living resources, mineral extraction, and the construction of military infrastructure. The history of human activity in Antarctica is relatively brief, but in this time there has been a series of quite distinct phases, culminating in the Antarctic now holding a unique position in the world. Activities in the Antarctic are governed by the Antarctic Treaty, which contains provisions dealing with environmental matters. The differences between the polar regions and the rest of the world, and between the Arctic and the Antarctic, significantly affect scientific and engineering approaches to the remediation of contamination in polar regions. This paper compares and contrasts the Arctic and Antarctic with respect to geography, configuration, habitation, logistics, environmental guidelines, regulations, and remediation protocols. Chemical contamination is also discussed in terms of its origin and major concerns and interests, particularly with reference to current remediation activities and site-restoration methodology.

The behaviour of Antarctic soils towards contaminant materials depends on the nature of the contaminant and the properties of the soil. Relevant properties are: depth to permafrost, whether the permafrost is ice-cemented or dry frozen; the active layer depth, active layer moisture content, and frequency of liquid water; soil salinity characteristics; and the geological composition of the soil materials.

Soil contaminations in the McMurdo region have been investigated through several years in a number of studies, including site surveys, field investigations, and experiments. Results of these studies are summarized in this paper and the significance of the contaminations is discussed. The behaviour of contaminants at the sites investigated conforms to existing knowledge of the soil properties. In the presence of some summer water or occasional moisture influxes from snowmelt, soluble contaminants may be transported variable distances through soils, both downwards and laterally, depending on the amount of water available. Ice-cemented permafrost restricts the downward movement of most contaminants but may aid distribution via lateral flow, especially low-freezing-point contaminants such as hydrocarbons. In dry-frozen soils, low-freezing-point contaminants may penetrate deeply into the soil.

With respect to the sites investigated, the heavy metal contaminations were typically above the values from undisturbed sites, but there may at times be appreciable natural variation. The presence of solid materials in soils — such as particles of plastics, wood, fibre, etc — represents a widespread and pernicious form of contamination, because they are foreign to the environment and are non-degradable.

The ways by which contaminants in freezing ground disperse and interact with associated ecosystems is a new and challenging field of applied research that is crucial to effective assessment, monitoring, and remediation in cold regions. Three key issues have been identified as needing urgent research and development. The first concerns the development and application of meaningful environmental guidelines for cold regions. This usually means that contaminants in freezing ground per se need to be considered in their broadest context by also addressing associated ecosystems, such as the receiving marine environment. The second issue concerns developing best practice for bioremediation of seasonally frozen soils. Of particular concern are the risks, benefits, and costs of using so-called bioproducts, which may not offer substantial improvements over biostimulation of indigenous cold-adapted organisms. The third issue concerns the need for assessment and monitoring protocols and cost-effective analytical tools. In this respect the potential use of field portable instruments deserves careful consideration and on-site testing. Taken together, development of these issues during the coming years will be crucial if the science behind managing contaminants in freezing ground is to catch up with the knowledge that underpins the remediation industry elsewhere.

The International Conferences on Contaminants in Freezing Ground are organised under the auspices of an International Steering Committee to promote a better understanding of the unique characteristics and problems posed by contaminants in freezing ground. The first meeting was held in Cambridge in 1997 and was attended by 33 participants from nine countries. Results from the meeting were reported in Polar Record in 1998 (volume 35). The themes covered at the first meeting reflected a broad range of interests, including a synthesis of the Arctic environmental strategy as it stood in 1997; the fundamental physical, chemical, and biological properties of contaminated frozen soils; experimental approaches to determining contaminant movement; and possibilities for in situ bioremediation of petroleum spills.

Twenty-fifth Antarctic Treaty Consultative Meeting Warsaw, Poland, 10–20 September 2002

Management Plan for Antarctic Specially Protected Area No. 130 TRAMWAY RIDGE, MT. EREBUS, ROSS ISLAND

Located on the northwest coast of Heard Island, a World Heritage-listed sub-Antarctic territory of Australia, Atlas Cove served as the site of the first permanently occupied Australian National Antarctic Research Expedition (ANARE) station (1947–55). Subsequent to its closure, Atlas Cove Station was abandoned and left largely to the mercy of the natural elements, although it has been visited and occupied on an infrequent basis by ANARE. All activities on the island are now subject to the provisions of the Heard Island Wilderness Reserve Management Plan. During 2000–2001 a major clean-up of the site was undertaken, with most of the remaining structures demolished and material collected for return to Australia and disposal. To assess the extent and intensity of contamination within the station area, soil and water samples were collected and analysed for petroleum hydrocarbons and heavy metals. Assessment of site contamination was made with reference to specific background control limits calculated for Atlas Cove Station, and comparison was also made with Australian and New Zealand guidelines for the protection of aquatic and terrestrial ecosystems. Contamination by heavy metals is evident throughout the station but not at levels of sufficient magnitude to infer a significant potential toxic impact on local ecosystems. Hence remedial action to reduce the concentration and mobility of heavy metals in soil and water is not a high priority, although monitoring of changes at the site through time is recommended. Contamination by petroleum hydrocarbons is at a level that may cause a significant toxic impact on the environment and requires further investigation to assess impacts and possibly to undertake remedial action. Given the large quantity of petroleum-contaminated soil present, remediation processes that can be carried out in situ are likely to be the preferable clean-up options. The benefits of remediation, however, must be balanced against any negative effect this might exert on the plant and animal wildlife that have recolonised this historically important site.

During the last several decades there has been much financial investment in the cold regions on projects (mining, oil and gas, etc) that can be the source of ground contamination and that require actions to prevent, mitigate, or remedy such effects. Yet contamination in freezing ground and its remediation have been the subject of research largely only in the last 10 years. This is a short time in terms of research and subsequent technology development, particularly as so few scientists are involved. Probably, therefore, many significant advances remain to be made.

Normally in the development of new technologies there is a driving financial input from industrial activity; a certain, if small, percentage of expenditures goes towards research and development. In the case of major geotechnical, contaminant-remediation projects in the cold regions, it appears that a substantially smaller percentage of expenditures than might be expected is going into inherently necessary research. The implication is that contamination management is not developing at a rate that would be the most effective and cost-efficient. The reasons for this are examined with regard to international funding of major construction projects in cold regions, and the associated requirements for contaminant management, and political and societal pressures. The potential scientific advances are examined and it is concluded that not only the contaminant management industry (consultants, contractors) but the industries behind cold-regions development and society more generally, would benefit greatly from an understanding of and provision for such advances.

The Peel-Caribou Staging Area, located along the Peel River, northern Yukon Territory, was used for exploratory drilling activities during the mid-1960s. Following abandonment of the project in 1975, waste materials were buried in a pit on site. An encroachment of the river on the waste pit in 1994 exposed the debris along with soils contamiated by DDT (1,1,1-trichloro-2,2-bis-(4-chlorophenyl)ethane), metals, hydrocarbons, and dichloromethane. The results of subsurface drilling in April 2000 and contaminants analyses, along with data from a geophysical investigation, indicated contaminated soils and debris were located in a 2-metre thick layer below the high-water mark of the riverbank, with an overburden of soil varying in depths from 3 to 4 m. The validation of various field test kits — including immunoassay test kits, PetroFLAGTM analyzer, and photoionization detector — as possible analytical tools for on-site testing was conducted during the site investigations. Site remediation was conducted in January–March 2002 while the river was frozen to facilitate excavations along the frozen and exposed riverbank as well as site access. The debris along the riverbank is usually submerged in the summer and autumn due to fluctuating water levels. Following the construction of a winter overland route to the site, the contaminated soils and associated waste were excavated and transported off-site for disposal. Based on the validation exercise, immunoassay test kits were used for on-site delineation and confirmatory testing during site remediation.

There is an urgent need to develop new technologies to address the problem of soil remediation in high-latitude regions. A field study was initiated in January 1997 in two contaminated soils in Terre Adélie (Antarctica) with the objective of determining the long-term effectiveness of two bioremediation agents on total and hydrocarbon-degrading microbial assemblages under severe Antarctic conditions. This study was conducted in two steps, from January to July 1997 and from February to November 1999 in the Géologie Archipelago (Terre Adélie, 66°40′S, 140°01′E). Changes in bacterial communities were monitored in situ after crude oil or diesel addition in a series of 600 cm2 soil sectors (20×30 cm). Four contaminated sectors were used for each experiment: diesel oil (10 ml), diesel oil (10 ml) + fertilizer (1 ml), Arabian light crude oil (10 ml), and crude oil (10 ml) + fertilizer (1 ml). Two different bioremediation agents were used: a slow release fertilizer Inipol EAP-22 (Elf Atochem) in 1997 and a fish compost in 1999. Plots were sampled on a regular basis during a three-year period. All samples were analysed for total, saprophytic psychrophilic, and hydrocarbon-utilising bacteria. A one order of magnitude increase of saprophytic and hydrocarbon-utilising micro-organisms occurred during the first month of the experiment in most of the contaminated enclosures, but no clear differences appeared between fertilized and unfertilized plots. Diesel-oil contamination induced a significant increase of all bacterial parameters in all contaminated soils. Crude-oil contamination had no clear effects on microbial assemblages. It was clear that the microbial response could be rapid and efficient in spite of the severe weather conditions. However, microbial growth was not clearly improved in the presence of bioremediation agents.

Major (Al, Fe), minor (Mn), and trace (Li, Cu, Ni, Cr, Cd, Zn, Pb) metals along with nutrients (TOC, TON, TS, TP) and enzymatic activities were determined in 18 surface sediment and two soil samples collected in six small bays of the Karelian shore of Kandalaksha Bay, White Sea, Russian Arctic. The studied sediments tended to be marine, with a major input of organic matter from autochthonous sources. Marine organic material might be an important carrier of trace metals in the examined sediments. According to sediment quality guidelines, all trace-metal contents were below the threshold levels. The results of azocasein-trypsin tests also suggested no significant contamination of analysed sediments and soils. A comparison of the trace-metal contents in the sediments examined with those of the western Arctic shelf showed higher levels of Zn and Cr in the Karelian shore. Presumably these disparities were related to regional differences in sediment chemistries rather than to any enhanced pollution within the studied area. Both geochemical composition and enzymatic-activities patterns among sites studied are largely controlled by the sediment granulometry. The evolution of sediments in the restricted exchange environments under investigation is caused by depositional conditions, which are strongly affected by small-scale hydrodynamic processes specific for each particular area. The most vivid examples are separating basins, where the fine-grained sediments enriched in organic matter — and thus in nutrients and metals — are formed under calm hydrodynamic conditions enhanced by severely restricted water exchange.

The Larsemann Hills provide a unique opportunity for studying the environmental impacts of four research facilities run by three nations (Australia, China, and Russia). Soil and water samples collected from the vicinity of each station approximately 10 years after their establishment were analysed for a variety of hydrocarbons, metals, and nutrients. Results confirm that hydrocarbon contamination is the most common impact of the stations. Nutrient enrichment of soil was identified within small areas of each station, and water samples obtained from several local tarns and meltpools revealed low-level contamination by metals and polyaromatic hydrocarbons (PAH). Faecal coliforms were present in intertidal pools adjacent to sewage effluent discharge but not in any other water bodies tested. The cumulative impact of the four facilities was an increase in the number of sites contaminated, rather than increased contamination at specific locations due to the additive effect of overlapping sources. The highest levels of contamination were extremely localised and the footprint of contamination arising from each of the facilities remained discrete from that of neighbouring stations. These data provide a baseline to compare environmental conditions at these locations in the Larsemann Hills before and after implementation of the Protocol on Environmental Protection to the Antarctic Treaty.

In North American cold regions, terrestrial spill-response tactics have evolved through clean-up experience with crude oil and refined petroleum products. Alaska has developed response tactics as guidelines for clean-up of petroleum-based spills. Generic application of any response tactic without regard for season, site-specific conditions, and equipment limitations can further damage an ecosystem. For example, the practice of igniting and burning petroleum product spilled onto frozen tundra without consideration of the anthropogenic effect on the surface energy balance may actually increase the vertical migration of the spilled product. Prior to application of any mitigation strategy to a release of petroleum product, the movement of the product through freezing soil needs to be better understood. Case studies are presented, and lessons learned from them are discussed.

Clean-up sites in cold climates present unique challenges for the analytical chemist, primarily because of transportation constraints and limited infrastructure. Excavation of chemically contaminated soils and dumps requires a quick turnaround for analytical results. This is mainly due to the cost factors involved in having expensive heavy equipment idle and the short working seasons, but also because of melting of exposed permafrost during excavation. Three options are available for conducting analyses at remote polar sites. These are off-site determinations, the use of on-site test kits (or simple procedures), and the deployment of a mobile laboratory. This paper discusses these options and provides details of available on-site techniques as well as specific examples of their application in remote northern sites. The design and operation of a mobile laboratory at Resolution Island, Nunavut, is described, and available test kits are compiled and reviewed.