Read PDF Impaired Wetlands in a Damaged Landscape: The Legacy of Bitumen Exploitation in Canada

Free download. Book file PDF easily for everyone and every device. You can download and read online Impaired Wetlands in a Damaged Landscape: The Legacy of Bitumen Exploitation in Canada file PDF Book only if you are registered here. And also you can download or read online all Book PDF file that related with Impaired Wetlands in a Damaged Landscape: The Legacy of Bitumen Exploitation in Canada book. Happy reading Impaired Wetlands in a Damaged Landscape: The Legacy of Bitumen Exploitation in Canada Bookeveryone. Download file Free Book PDF Impaired Wetlands in a Damaged Landscape: The Legacy of Bitumen Exploitation in Canada at Complete PDF Library. This Book have some digital formats such us :paperbook, ebook, kindle, epub, fb2 and another formats. Here is The CompletePDF Book Library. It's free to register here to get Book file PDF Impaired Wetlands in a Damaged Landscape: The Legacy of Bitumen Exploitation in Canada Pocket Guide.
These books may interest you
Contents:
  1. Imprudence: Book Two of The Custard Protocol by Gail Carriger PDF Book - Mediafile Sharing
  2. Ditt søk på "assemblages" ga 1890 treff.
  3. These books may interest you

During dry periods, considerable water can be stored in wetlands that provide small, sustained baseflows to streams and evapotranspiration to the atmosphere Mitsch and Gosselink In contrast, during wet periods, the capacity of wetlands to store water is exceeded and the saturated areas act as conduits of overland flow from the uplands to the streams. In areas of permafrost e. The interactions of the mass and energy cycles and the physical, chemical, and biological processes that drive them must be considered to understand the potential impacts of natural resource development on boreal water resources.

Water enters the ecosystem as precipitation. It is first intercepted by surface vegetation, where a portion is returned to the atmosphere by evaporation, and the remainder falls to the ground as throughfall. Water evaporates from plant and soil surfaces or infiltrates and is transpired by vascular vegetation, collectively known as evapotranspiration, and any water remaining is stored in the soil. Upon soil saturation, water flows via surface, shallow subsurface, or deeper groundwater pathways, creating areas of discharge upward movement of water to the surface to surface bodies of water or recharge downward movement of water into groundwater storage.

Storm and snowmelt intensity e. In general, surface flows predominate where there is steep relief, shallow soils, and or deeper soils with saturated conditions, and deep flows predominate where there is gentle relief, deep soils, and unsaturated conditions Dunne and Leopold Forest ecosystems are sources of nutrients to surface water, with important downstream water quality implications Waring and Schlesinger ; Chapin et al. Within forests, water flow pathways influence water chemistry by determining the materials with which water interacts.

Water travelling along shallow flow pathways will interact with organic-rich compounds such as freshly fallen leaves and or roots and forest floor materials, whereas deeper flow pathways interact with mineral-rich parent materials. The residence time of water moving along the flow path will also influence water quality McGuire et al. Residence times are governed by presence or absence of storage structures e. Short residence times create oxic conditions and result in less interaction with soils that may leach into the water than longer residence times that have anoxic conditions and more interaction with soils McGuire et al.

The residence time of water in turn alters the soil chemical environment, which alters the form and thus also the solubility and mobility of nutrients Chapin et al. Water quantity and quality changes throughout the year reflecting changes in precipitation inputs e. For example, water chemistry is typically more dilute in spring due to low biological processing under the snowpack and high quantities of available water during snowmelt. In contrast, water chemistry is typically more concentrated in the summer due to high biological processing and low quantities of available water Band et al.

In the eastern boreal zone, with shallow upland soils overlying the high relief of the Canadian Shield, water quantity and quality is predominantly determined by variable source area VSA regulated near-surface flows Fig. VSA refers to the concept that runoff-generating areas in the landscape vary in size and configuration over time. In VSA-controlled landscapes, as the groundwater table rises to intersect the surface soils, nutrients that have previously accumulated in the surface soils are mobilized and flushed to the stream Creed and Sass Topography, via VSA control, influences the hydrologic flushing of nutrients in various ways.

It affects i the generation of nutrient supply e. This mechanism, or variations of it, has been used to explain the export of carbon Hornberger et al. The western boreal zone is characterized by deeper upland soils and lower relief, and water quantity and quality is typically not regulated by VSA dynamics Fig. In nonVSA-dominated landscapes, the predominance of primarily vertical flows and deep subsurface pathways regulate water and nutrient transfer from land to aquatic systems Creed and Sass Thus, consideration has to be given to local, intermediate, and regional groundwater flows to understand the chemistry of surface waters.

In boreal forests with these complex hydrogeological systems, predicting the chemical responses of surface waters to disturbance is extremely difficult Devito et al. However, the size and configuration of surface saturated areas where water flowpaths created by these complex hydrogeological systems intercept with the land surface have been used to explain total phosphorus loading to boreal surface waters e. Wetlands can have a large impact on water quality, even if they occupy only a small percentage of basin area. Wetlands are unique in that they act as reservoirs of water and bioreactors of nutrients during drier periods and conduits of water and nutrients during wet periods.

In particular, there is a strong connection between the presence and extent of wetlands and the concentration of dissolved organic carbon in surface waters Dillon and Molot ; Creed et al. Similarly, wetlands have been shown to have an important role in nitrogen and phosphorus loading to surface waters e. Boreal ecosystems regulate weather and climate through both direct mechanisms such as transpiration cooling and albedo effects Oke ; Barnett et al.

Changes to global climate and hydrologic cycles have the potential to strongly impact boreal water resources Price et al. The key impacts from climate change on the water cycle will come in the form of extreme events such as droughts and floods, seasonal shifts in flow regimes, and reduced winter ice coverage NRTEE These hydrologic changes to the water cycle are likely to have positive feedbacks i.

Climate models show that changes in temperature and precipitation are likely to continue affecting the partitioning of water between evapotranspiration and runoff as well as the amount of water stored in glaciers, snowpack, lakes, wetlands, soils, and groundwater. Recent modelling studies suggest that the interior of North America, including the western boreal zone, will become much drier and may no longer be able to support forests Hogg ; Dai , ; Price et al.

These large scale vegetation changes are likely to have large impacts on water resources Baldocchi et al. The natural resource sectors make a significant contribution to the Canadian economy representing The thermal power-generating sector was responsible for the greatest gross water use, while agriculture accounted for the greatest water consumed Statistics Canada ; NRTEE Transportation infrastructure is an artefact of humans interacting with the landscape Coffin Pasher et al.

Canada's Tar Sands: The most destructive project on Earth? - Truthloader

There is little scientific literature on impacts of roads in the boreal zone even though roads are a pervasive linear disturbance that has no natural corollary. They create gaps, fragment habitats, alter access to humans and predators, provide vectors for introduction of invasive species, change local climate, and influence local hydrology Trombulak and Frissell The effects of roads often last well beyond their construction or even their use , with older roads tending to have greater effects on water resources because of the places in the landscape where they were constructed and because construction practices were more intrusive than more recently constructed roads Wemple et al.

These effects persist as long as the road remains a physical feature, continuing to alter flow routing even after abandonment and revegetation Trombulak and Frissell Road construction associated with natural resource development influences water quantity through the creation of road surfaces, cutbanks, ditches, and culverts Jones and Grant that contribute to changes in the timing and routing of runoff Trombulak and Frissell Road surfaces create increased overland flow due to an impervious surface layer that creates reduced infiltration capacity La Marche and Lettenmaier ; Tague and Band Cutbanks intercept upslope subsurface flow La Marche and Lettenmaier The depth of the road cut, which varies with local slope, and width of the road will determine the amount of subsurface runoff that is intercepted Tague and Band Ditches and culverts provide a conduit of flows directly to the channel, increasing the flow routing efficiency by extending the drainage network Wemple et al.

Road location on the landscape, specifically position on hillslope profile, influences the effects of roads on hydrology Jones et al. However, there are instances where, instead of concentrating flow, ditches and culverts diffuse flow if water is routed to relatively dry areas. Thus, the effect of this concentration of flow will depend upon the characteristics of the receiving area Tague and Band Wetland habitats can be destroyed or created with alterations to surface or subsurface flow Trombulak and Frissell For example, wetland road crossings may block drainage passages and groundwater flows, effectively raising the upslope water table and lowering the downslope water table Forman and Alexander ; Partington and Gillies Roads, in combination with forest harvesting, can have dramatic impacts on both the timing and volume of water during storms Jones and Grant However, despite some generalizations that roads have significant effects on peak flow, the impacts will vary with underlying geology, soil texture, vegetation, type of road construction, and both seasonal precipitation and local storm events Lugo and Gucinski ; Tague and Band For example, in regions with high precipitation and high relief landscapes e.

Hydrologic effects are likely to persist for as long as the road remains a physical feature altering flow routing Trombulak and Frissell Little effort has been expended in understanding the impacts of roads in low-relief landscapes. Roads affect water quality by increasing inputs of dust, generating higher erosion rates and therefore sediment loads, and increasing the turbidity of the waters Reid and Dunne ; Partington and Gillies thereby impacting aquatic biota Kreutzweiser et al.

Travel intensity, road surface type, vegetation cover, climate, geologic substrate, road maintenance, and road-stream connectivity are primary factors in regulating sediment production in road systems Lugo and Gucinski High rates of sediment production from road surfaces occur in the year immediately following road construction but diminish rapidly over time Wemple et al.

Trombulak and Frissell identified five classes of chemicals that roads contribute to the environment: heavy metals, organic molecules, ozone, nutrients, and chemicals for de-icing and dust control. This study indicates that most contamination declines within 20 m of the road but that elevated levels of contaminants often occur m or more from the road Trombulak and Frissell Roads will continue to be a part of industrial landscapes of the boreal zone.

It is likely that road networks will become denser and expand farther north in the boreal zone as natural resource exploration, development, and the associated infrastructure increase. Consequently, the influence on water resources from road construction is also likely to increase. Road construction has a lasting legacy. Even if access to roads is restricted, the road footprint never completely disappears, and hydrologic flows continue to be affected. There is potential to offset the impacts of roads to some degree by mitigation measures.

Recent technological advances enable land planners and managers to improve the location of roads, the location and installation of culverts, and the selection of appropriate road surface materials on roads near water. For example, the Government of Alberta has used a technique for mapping wet areas to generate databases available to public to optimize road design White et al. In collaboration with Ontario Ministry of Natural Resources, FP Innovations has summarized the tools and resources available for best management practices for roads Partington and Gillies and state-of-practice review Gillies focussing on the unique challenges for road construction through wetlands.

Forest management activities occur in all provinces, and to a much more limited degree in the Yukon and Northwest Territories, with the boreal zone host to a significant fraction of forest management activities in Canada Fig. Within the spectrum of forest management activities, including timber harvesting, site preparation, planting, competition management, and stand tending, only timber harvesting activities have received significant research attention with regards to their impact on water resources.

Timber harvesting in the boreal zone typically employs clearcut harvesting e. Forest management strategies in the boreal zone have evolved and large, regularly shaped cuts typical of the past have been replaced with smaller, irregularly shaped cuts containing residual material to address biodiversity concerns Potvin et al. An emerging issue in boreal forestry is biomass harvesting for bioenergy. Until relatively recently, slash nonmerchantable wood comprised of small diameter trees, tops and branches from the harvest was either left on the ground on-site or de-limbed at the road.

Now there are opportunities for use of this biomass in alternative wood products e. The removal of this material has implications for site productivity and water resources Thiffault et al. Our understanding of how timber harvesting affects water resources is based largely on a century of comparison studies of harvested versus unharvested paired-basin studies c.

Brown et al. The primary assumption underlying paired-basin studies, that changes in streamflow between a harvested and unharvested basins with similar climate, geology, and vegetation isolate and quantify the impacts of harvesting, has proven to be a powerful tool in understanding the effects of timber harvesting. Canada has a long history of paired-basin studies Buttle et al. However, not all of these studies have forest management activities as a primary focus and only a small proportion are located in the boreal zone Fig. These paired-basin studies, combined with stand- or site-level studies, have contributed greatly to our understanding of the effects of timber harvesting of water quantity and quality.

In general, reduction of forest cover by timber harvesting and other natural and anthropogenic disturbances reduces canopy interception and evapotranspiration, leading to increases in soil moisture Buttle and Metcalfe ; Guillemette et al. The characteristics of the topography, soil, and surficial geology will determine how the increase in soil moisture is expressed in terms of increases in groundwater recharge versus runoff.

The processes connecting the changes in coverage, composition, and structure of tree canopies due to harvesting and the increase in groundwater recharge or runoff are numerous, primarily driven by the water balance and radiation balance National Research Council There are, of course, many localized processes and the exceptions to these general principles demonstrate the importance of the particular combination of climate, geology, topography, and soils Devito et al. Forest canopy intercepts precipitation where a portion is subsequently returned to the atmosphere by evaporation or delivered to the ground surface as throughfall and stemflow.

The amount of precipitation intercepted varies with tree species.

Imprudence: Book Two of The Custard Protocol by Gail Carriger PDF Book - Mediafile Sharing

Elliott et al. Price et al. In the boreal zone, snowfall is a significant contributer to the water balance of most basins. Pomeroy et al. Comparing mature, clearcut, and regenerating stands in northern Saskatchewan, Pomeroy and Granger found that clearcuts accumulated the most snow, followed by mature mixed wood stands, mature jack pine stands, and regenerating stands 15 years old had the least accumulation. Similar results were found in other regions, including conifer stands in British Columbia Winkler et al.

The size of canopy openings in relation to the surrounding forest influences the radiation balance within forest stands. Increases in solar radiation have pronounced effects on evapotranspiration and snowmelt Winkler In a study of a variety of forest types in northern Manitoba, Metcalfe and Buttle showed that increasing canopy density, measured as gap fractions, reduced incoming short-wave radiation and wind speeds, reducing latent and sensible heat fluxes and subsequent melt rates.

Pomeroy and Granger found that clearcuts underwent an earlier and more rapid melt. Faria et al. The impacts of timber harvesting on runoff related to the water and radiation balances, together with site-specific changes to water flow pathways associated with land surface erosion, compaction, rutting, and loss of organic matter, have been the subject of many general reviews e.

The majority of these studies focused on how timber harvesting affects peak flows because of concerns for flooding and associated increases in stream scouring and bank undercutting, which in turn can affect water quality and aquatic habitats downstream through transport and subsequent deposition of sediment Alila and Beckers In the eastern boreal zone, dominated by a hydrologic regime characterized by high precipitation and relatively high relief, runoff responses to forest management are extremely variable, ranging from negligible to moderate depending on the amount of basin disturbed and the prevalence of skid trails and road ditches.

The relatively large peak flow response, when compared to 50 other similar studies globally, was attributed to increased channelized flow to the basin outlet due to skid trails and road ditches Guillemette et al. They did, however, report that there was some augmentation of base flows in summer months and suggested the muted responses reflected the ability of large basins to buffer the response to timber harvesting. Metcalfe and Buttle noted that water storage and evaporation in small wetlands and ephemeral surface depressions is a fundamental component of the basin water balance that may influence runoff response.

In the western boreal zone, dominated by a hydrologic regime characterized by low precipitation and relief, runoff responses were more difficult to discern. In the aspen-dominated mixedwood forest of northeastern Alberta, Devito et al. In these areas, where deep sedimentary deposits are interspersed with clay lenses, greater infiltration and increased groundwater recharge lead to raised water tables following harvest Smerdon et al. Runoff generation only occurred under exceptional circumstances one in 20 years and within specific landscape units ephemeral draws and wetlands that were only rarely hydrologically connected to surface waters.

Swanson and Hillman examined the effects of timber harvesting in nine control and nine harvested basins in the foothills of the Rocky Mountains in west-central Alberta, where precipitation and relief are much greater than the boreal plains to the east. Timber harvesting causes many physical, geochemical, and biological changes to a forest ecosystem. The impacts of timber harvesting on stream water temperatures are variable. Timber harvesting results in higher incident radiation on the soil surface that results in an increase in soil temperatures. Timber harvesting also results in changes in wind patterns that influences soil temperatures.

Changes in soil temperature influence temperatures of saturated and unsaturated water flow and, thus, the temperatures in downstream aquatic ecosystems Johnson and Jones Temperatures in small headwater streams in sub-boreal Engelmann spruce and subalpine fir forest ecosystems of British Columbia remained four to six degrees warmer and diurnal temperature variation remained higher than in the control streams regardless of riparian buffer retentions five years after the completion of timber harvesting treatments MacDonald et al.

Although initially the high-retention treatment acted to mitigate changes in temperature, successive years of wind throw reduced forest canopy density creating temperature impacts equivalent to a clearcut MacDonald et al. In contrast, in more eastern parts of the boreal zone, Tremblay et al. Similarly, Kreutzweiser et al. Steedman et al. Timber harvesting has been shown to have variable effects on water temperatures, with the largest impacts usually in early season of the year following canopy openings when the riparian canopy is drastically reduced either by harvesting or post-harvest wind throw.

Erosion occurs when there has been physical disruption to the soil surface e.

Ditt søk på "assemblages" ga 1890 treff.

Erosion results in the transport of sediment into adjacent streams, wetlands, and lakes. This material takes with it nutrients that are embedded within or sorbed i. MacDonald et al. Tremblay et al. Kreutzweiser et al. In addition to the sediments from erosion, Steedman and France found that wind-blown sediment from black spruce — jack pine clearcuts, roads, and skid trails, where soil disturbance is large and able to reach the lake, may have led to elevated levels of littoral sedimentation, although it was thought this mechanism would not cause important changes in water quality. Although some studies do not examine sedimentation directly, many have found that water clarity is reduced by timber harvesting over a variable range in time one to four years following harvest Carignan et al.

Changes occur to soil nutrient cycles post-harvest see review by Kreutzweiser et al. Nutrient cycles such as carbon, nitrogen, and phosphorus are driven primarily by microbial activities. Timber harvesting affects both the environmental constraints on and the sources of organic material for decomposition Kreutzweiser et al. The warm, mesic, and aerated conditions created from timber harvesting operations are ideal for microbial metabolism and their mineralization of organic matter. The rate and timing of decomposition is also constrained by the amount of organic material left following harvest and its quality i.

The amount and type of residue slash retained on the site will differ depending on timber harvest approach and whether whole tree de-limbing at road, less residue in plot or tree-length de-limbed where cut, more residue on plot methods were used. Following timber harvest, the demand for nutrients from vegetation is low because of the removal of plants and the lag time in regeneration Kreutzweiser et al. Thus, high concentrations of nutrients can accumulate in the soil and soil pore water, creating the potential for leaching into groundwater or loading to downstream ecosystems Kreutzweiser et al.

Disruption of the forest floor containing easily decomposed residues leaves and bark or damage to wetlands where there is deeper organic layers in combination with changes to soil environmental conditions that enhance microbial activity following harvesting can create hydrologically mobile sources of dissolved organic carbon DOC. A rise in groundwater level following timber harvesting can mobilize DOC both during peak and base flow conditions Laudon et al.

Most studies reviewed found an increase in surface water DOC concentrations following harvest that were maintained for a few years followed by a decline towards pre-harvest conditions in lakes Carignan et al. A few studies reviewed showed no effect in streams Hillman et al. The specific silvicultural practices applied have an impact on how long surface water DOC concentrations remained elevated. For example, Schelker et al. However, since DOC concentrations in undisturbed basins are closely linked to presence and extent of permanently or transiently saturated soils Dillon and Molot ; Creed et al.

Timber harvesting effects on nitrogen mobility and export are mediated by microbial processes affecting mineralization and nitrification Mallik and Teichert Studies examining the impacts of timber harvesting on nitrogen in surface waters have observed a variety of responses in boreal lakes. These include increases in total nitrogen Lamontagne et al. Other studies have shown no effect on total nitrogen Garcia and Carignan ; Prepas et al. Variation in nitrogen response to harvesting is due to local site factors such as vegetation type controlling carbon to nitrogen ratio, local environmental conditions such as temperature and moisture controlling rates of mineralization, and local topography affecting its aquatic versus atmospheric fate Holmes and Zak ; Lamontagne et al.

Timber harvesting effects on phosphorus export is related to soil erosion and soil properties that influence biotically controlled mineralization processes or abiotically controlled adsorption and desorption processes. Landscape position affects these processes Mallik and Teichert Studies examining the impacts of forestry on phosphorus loading to surface waters reveal a variable response. Several studies observed increased concentrations of total phosphorus in lakes Carignan et al. Other studies observed no change in concentrations of total phosphorus concentrations Evans et al.

Base cation calcium, magnesium, sodium, potassium and anion chloride, sulphate exports are controlled primarily by soils, geology, pH, and organic matter associations rather than decomposition processes. Base cations in water were generally observed to increase following timber harvesting.

Increases were observed for calcium Carignan et al. However, Steedman observed decreases in calcium and magnesium. Trends in acid anions are less well studied, and include sulphate increases Carignan et al. Water pH is primarily driven by balances in cations and anions and, in general, timber harvesting appeared to have little effect on pH Hillman et al. Studies investigating the impacts of forestry on water quality parameters within the boreal zone have tended to focus more on lakes than streams, with more studies from the eastern boreal zone compared to the western boreal zone.

Although the majority of studies have shown short-term increases in many of the nutrients, it is not well known what the longer-term changes are following timber harvesting and stand regrowth. Nutrients may differ in their responses, with mobile nutrients potassium, chloride, sulphate, nitrate that are released following a harvest being rapidly flushed out of the basin e.

The rate of decline in nutrient export will be determined by microbial demand for nutrients during decomposition, vegetation demand for nutrient uptake, and water availability for solubilizing and mobilizing nutrients. Forestry operations have been shown to increase mercury and methyl mercury output from boreal catchments Porvari et al.

Clearcutting and or site preparation significantly increases the mobility of total mercury and methyl mercury accumulated in forest soil and may be an important factor for the total input of mercury to boreal freshwater ecosystems Porvari et al. The study of Garcia et al. More than a century of research into interactions between forestry and water resources has led to significant improvements in forest management practices to protect water resources Ice et al.

Significant improvements have been made in forest management planning, beneficial management practices, and certification standards. Improving road placement White et al. The role that riparian buffers play in mitigating forest management impacts on water resources has been evaluated Buttle Fixed-width riparian buffers have become the norm for streamside protection from forest management activities, due to their relatively easy implementation in forest planning, yet few experiments have been done to test the efficacy of riparian buffers of a particular width or explore site or landscape-specific modifications Richardson et al.

The study of Prepas et al. In the same region, Creed et al. The relationship between wet area and return period was proposed as an approach for estimating risk associated with harvesting in these critical areas, enabling land managers to design variable width riparian buffers based on the level of risk they are willing to accept with respect to increasing nutrient loading to surface waters following harvesting Creed et al. Modern forest management strategies aim to emulate natural disturbance as much as possible in its methods Hunter This has implications for the protection of water resources, because natural disturbances often occur in riparian buffers, and emulating those disturbances will require timber harvesting closer to water than previously allowed under conventional riparian buffers Kreutzweiser et al.

This emphasis on emulation of natural disturbance is providing impetus for new directions in basin and riparian forest management Naylor et al. Implementation will also need to consider conditions under which riparian buffer harvesting does not mimic natural disturbances. Although achieving harvest patterns that are similar to fire patterns near water can be successful, creating similar response in processes is more difficult. For example, fires in riparian buffers result in standing dead trees that can provide shade temperature control and pulsed inputs of large wood organic matter input and retention to streams, whereas harvesting in riparian buffers generally does not Moore and Richardson A similar problem is encountered with emulating the impacts of fire on water quality.

In a series of syntheses, Buttle et al. For example, DOC, mercury, sodium, and potassium responded more strongly to harvesting, whereas nitrate-nitrogen, phosphorus, calcium, and magnesium responded more strongly to fire, with other parameters responding similarly. Given the importance of forestry operations in the boreal zone, a large knowledge gap remains in understanding the persistence of impacts of timber harvesting activities.

Most studies do not continue beyond two or three years post-harvest. While studies of this duration may capture recovery of rapidly responding effects, it may not capture some of the longer-term impacts or the time scales of recovery in runoff and water quality that have been observed in some forest ecosystems Carignan and Steedman ; Nitschke Furthermore, studies on the impacts of forestry on water resources have been predominantly conducted outside of the boreal zone or within the eastern boreal zone, and the applicability of these results to the entire boreal zone is unknown.

Also, studies on the impacts of forestry on water quality within the boreal zone have focused primarily on lakes, not streams. Although some general trends in water quality parameters were observed, there was considerable variability and inconsistency in water quality observations, reflecting the substantial spatial heterogeneity and temporal variability of drivers of hydrologic and biogeochemical processes within the boreal zone sensu Devito et al. Several studies have considered the impacts of harvesting intensity, and typically the impacts became more pronounced with increasing intensity of harvest, when normalized by the lake surface area or volume Carignan et al.

However, forest management studies have typically focused on low order, headwater basins, and the spatially cumulative impacts of timber harvesting at larger scales has rarely been evaluated Buttle and Metcalfe , or in combination with other landscape disturbances Buttle et al.

Furthermore, scaling impacts from the stand level to the basin or landscape scale still remains a challenge. Timber harvesting in treed peatlands presents unique challenges for forestry. Timber harvesting within peatlands is not a widespread practice in the Canadian boreal zone as it is in the boreal zone of northern Europe Poulin and Pellerin , although it occurs in certain areas, such as the Clay Belt in Ontario and Quebec and in north-central Alberta. Tree productivity in peatlands is generally low because of a high water table, poor aeration Campbell , low substrate temperature Lieffers and Rothwell , and inadequate nutrient availability Tilton However, treed peatlands have marketable black spruce Picea mariana and tamarak Larix laricina that are harvested primarily as high-quality pulpwood Locky and Bayley These elevated water tables can persist for many years.

Pothier et al. Watering-up creates conditions conducive for paludification i. Silvicultural practices within peatlands commonly include draining to improve forest productivity prior to harvest Poulin et al. Watering-up can alter local downstream flows, although there has been no recent work to quantify the potential magnitude of impact. The increase in water table following timber harvest in treed peatlands creates an anoxic environment Aust et al. Peatland draining prior to timber harvest causes changes in water chemistry, opposite to that of watering-up, as a result of increased oxygen transport into the peat Silins and Rothwell Numerous negative effects of peatland draining have been observed, including increases in suspended sediments, nutrients, specific conductivity, and pH of peat soil water Lieffers and Rothwell ; Lieffers ; Rothwell et al.

These water chemistry changes have the potential to influence downstream water quality during periods when the peatlands are hydrologically connected in the regional flow network e. Changes in demand for different wood products will determine if forest management activities within treed peatlands are likely to expand or decline. Extensive research that occurred during eras when demand for forest products from peatlands was high and from the European experience has identified many beneficial management practices to minimize impacts on water resources.

Although peatland draining following clearcutting or pre-commercial harvesting helps in the recovery from watering-up, it is considered a costly and remedial approach to the problem Marcotte et al. For example, drainage should be limited to the first cohort stand following harvesting Lavoie et al. Preventive measures, including silvicultural treatments that promote regeneration and evapotranspiration, along with protecting understory vegetation, should be employed to limit water table rise Lavoie et al.

Partial cutting scenarios also conserve the vertical complexity of the stand that is essential to the recovery process Marcotte et al. This requires the use of appropriate equipment to minimize site disturbances while the ground is frozen Locky and Bayley Applying these practices will help in minimizing negative impacts to water resources within commercially viable forested peatlands.

During the same year, Canada ranked first in world production of newsprint Boreal forests are the dominant contributor to the pulp and paper industry. As of , there were 17 active and 7 closed or decommissioned pulp and paper mills in the boreal portion of the commercial forest fig. The pulp and paper industry is capital-intensive, characterized by complex system processes to convert cellulose fiber from trees into a wide variety of traditional products such as pulps, papers, and paperboards Environment Canada a and emerging products such as fibre-bioplastic composites NRCan b.

Wood is reduced to fiber either by cooking in chemicals or by mechanical means Environment Canada a. The fibers are then mixed with water, adhering to one another as the water is removed by pressure and heat. Chemical pulping kraft and sulfite process uses sulphur to extract fiber that is exceptionally strong and is used for magazines, printing and graphics papers, grocery bags, and corrugated packaging Biermann Mechanical pulping mills physically shred wood into pulp with grindstones and or heat to produce pulp that has weaker fibers and is commonly used for newspapers Biermann Large volumes of water are required for processing and cooling during pulp and paper production, however most of the water is not consumed.

The large amounts of water used in processing and cooling reappear as effluent Pokhrel and Viraraghavan There is no evidence to suggest that boreal water quantity is significantly affected by water use in the pulp and paper industry. Pulp mill effluent is a known pollutant of surface waters Walden Pollutants are generated at various stages of the pulping and paper making process Pokhrel and Viraraghavan Effluents are a complex combination of waste streams produced in debarking, pulp washing, bleaching, and regeneration of cooking chemicals Pokhrel and Viraraghavan ; Hewitt et al.

Chemicals in effluents may be from the wood itself or from chemicals added during the pulping and bleacing process and include suspended solids, lignins, resins, fatty acids, volatile organic carbon e. During the s, pulp and paper production worldwide became an area of increased environmental scrutiny by the public as dioxins and furans in effluents and paper products were found to have toxic effects on aquatic organisms McMaster et al.

As a result of studies conducted internationally and in Canada, new regulations came into force in to set revised limits for biochemical oxygen demand BOD; the amount of oxygen needed to decompose organic matter , total suspended solids TSS , and dioxins and furans Environment Canada b. To meet the new regulatory limits, the industry was required to make process changes e. Effluents are now treated with both primary treatment to remove solids in settling basins, and secondary treatment to adsorb, settle, and promote microbial breakdown of biodegradable material to reduce BOD and levels of toxic organic compounds Pokhrel and Viraraghavan ; Hewitt et al.

Since the Pulp and Paper Effluent Regulations under the Fisheries Act came into force in , there have been declining trends in discharge loads of total suspended solids, adsorbable organic halides, dioxins, and furans and declines in BOD Chambers et al. Changes to effluent treatment to reduce contaminants have not reduced nutrient load.

Eutrophication that results from elevated nutrient concentrations in water remains a predominant environmental issue for pulp mill effluents Bothwell ; Biermann , Chambers et al. This is particularly a concern in northern boreal rivers where they are naturally nutrient deplete Chambers et al. The increased nutrient concentrations result in increased production of phytoplankton and aquatic plants, cause changes in the abundance and composition of consumers, and contribute to declines in dissolved oxygen Smith et al.

These nutrient concentrations were elevated downstream of the pulp mills, particularly during the low discharge periods of fall and winter September—April; Chambers et al. These elevated nutrient concentrations extended 4— km downstream of the point of effluent discharge Chambers et al. Global market trends, including increased demand for paper for small printers but declines in newsprint coupled with changing markets in which there is greater use of recycled fibre and fibre from plantations Whitman , has affected the viability of the Canadian pulp and paper industry FPAC Changes or recovery in traditional markets and acceptance and application of new technologies will impact how this sector develops into the future.

Declining newsprint demand and improved effluent treatments indicate that effects of toxic compounds in pulp mill effluents on water quality are likely to decline in the boreal zone. Furthermore, compliance with toxic substance control regulations over the past couple of decades has resulted in improved water quality of pulp mill effluents Environment Canada b. However, studies from the western boreal forest indicate that nutrient additions from mill effluents continue to be a persistent challenge and will pose risks of eutrophication effects in downstream water bodies.

Schindler and Lee point out that eutrophication in riverine boreal lakes is an increasing problem, and they suggest that the contribution of pulp mill effluents has to be considered along with cumulative effects of municipal sewage, agricultural, and shoreline developments. As a result of research from the Northern River Basin Study, nutrient loading to the Athabasca and Wapiti rivers has improved and pulp mills are required to develop nutrient minimization plans and investigate new methods to reduce nutrient discharge Chambers et al.

These examples from the western boreal suggest that continued improvements in effluent processing technologies are warranted to further reduce nutrient and suspended sediment loads. Canada is the third largest producer of hydroelectricity in the world behind China and Brazil accounting for approximately In , electricity generation in Canada amounted to In , there were large dams greater than 5 m in crest height across Canada in the boreal zone Brandt et al.

Two hydroelectric power projects within the boreal zone, Le Grande complex Quebec and Churchill Falls Labrador , are ranked among the largest projects in the world in terms of capacity and reservoir size International Hydropower Association ; Lewis Canada has diverted more water by damming rivers than any other country Dynesius and Nilsson ; Ghassemi and White Although the distribution of dams is considerable Fig.

Free flowing blue and dammed orange rivers of Canada based on data from Dynesius and Nilsson Conventional hydroelectric power requires construction of dams to impound water to generate electricity and is the most common type of power generation in the boreal zone. Thermal power generation uses heat energy from fossil fuels or uranium to produce steam to drive turbines.

Run-of-the-river installations are small, low capacity hydroelectric power installations where natural flow of the river itself is used, requiring little to no water retention within reservoirs. In addition to generating stations and impoundments, hydroelectric power developments also bring with them thousands of kilometres of transmission lines along linear corridors that are cleared of trees and maintained by herbicides and cutting Urquizo et al.

Of all the modes of hydroelectric power generation, conventional hydroelectric dams have the largest impact on boreal water resources, with impacts both upstream and downstream of the dam Baxter ; Rosenberg et al. Direct and often obvious upstream impacts include flooding of riparian buffers, wetland and upland habitats, conversion of lotic flowing environments to lentic standing water systems, shoreline erosion with water level fluctuations including thermokarst slumping where permafrost exists , and altered groundwater recharge patterns.

The amount of water impounded upstream of a dam differs greatly from one site to another depending on the local topographic relief Baxter Upstream flooding associated with conventional hydroelectric dams is also the main cause of peatland loss in the country Rubec Although recent data were not available, in the early s, approximately ha of peatlands were flooded, mostly in Quebec, Manitoba, and Alberta Rubec ; Urquizo et al. Downstream impacts of hydroelectric dams include decreased groundwater recharge, streambank erosion, and associated change in stream morphology Baxter ; Rosenberg et al.

Conventional hydroelectric dams do not diminish the magnitude of downstream water flow, unless it involves large reservoirs that lead to increased evaporation losses. However, the timing of water flow is significantly altered to meet electricity demands Woo and Thorne Changes to downstream flow occur immediately after the dam construction is complete; flows are dramatically reduced during the time required to fill the reservoir, sometimes for up to several years Rosenberg et al.

Once the dam is in operation, the natural river flow regime is altered, including changes to the magnitude, frequency, duration, timing, and rate of change of flows Magilligan and Nislow Alteration to the natural river flow regime has consequences not only for water resources, but also for the entire ecological integrity of the river system Poff et al. Hydroelectric power developments characteristically trap high spring flows for storage in reservoirs and release higher-than-normal flows in winter when the power is needed Woo and Thorne This results in an attenuation of the normal hydrograph in spring and enhancement in winter Rosenberg et al.

This leads to a decrease in the amplitude of annual variations in water levels, although a higher frequency of small-amplitude, short-period variations may result as the discharge is varied with electricity demand Baxter The regulation of flows that result in little to no annual spring flooding has been identified as an important impact on delta ecosystems that depend upon flooding for replenishment of water and nutrients Woo and Thorne Weirs were built to recreate the hydraulic damming effect of the pre-impoundment Peace River to restore flooding to the delta Rosenberg et al.

However, paleolimnological evidence indicates that recently observed dryness is part of a longer trend, which began some 20—40 years prior to Peace River regulation and not out of the bounds of historical variability Wolfe et al. Many large hydroelectric power projects divert water from the natural basin into a neighbouring basin Ghassemi and White Such diversions further exacerbate downstream flow patterns, by decreasing flows in the contributing river and increasing flows in the receiving river Newbury et al.

Disruptions of freshwater flows, particularly for the many boreal rivers flowing northward to the Arctic Ocean, affect the timing of the spring breakup of ice in the lower reaches of the river, hastened by the increased hydrostatic pressure of water flowing from the south to the north Baxter Any or all of these changes in upstream and downstream flow regimes have implications for the aquatic organisms that live in those habitats Rosenberg et al.

Other forms of hydroelectric power generation have less impact on water quantity. Run-of-the-river hydroelectric installations create minimal changes in flow, since they have little to no reservoir retention. The purpose of the dam in a run-of-the-river installation is to direct and control the flow of the stream and little water is impounded Baxter However, if there is an increase in the popularity of run-of-the-river power generation, the cumulative impacts of multiple installations along a river section will need to be considered Douglas Thermoelectric power is one of the largest water users but not consumers among natural resource sectors in Canada Statistics Canada Oil and coal-fired thermal power generating plants generally use and discharge more water than natural gas-fired plants, and gas-fired plants are becoming more prevalent.

The main impact on water quantity with thermal power generating stations is the loss of water through evaporation during steam generation or during cooling, if cooling towers are parts of the operation Smith and Tirpak ; Statistics Canada Conventional hydroelectric power generation, through changes in upstream and downstream flow regimes, has large impacts on water quality.

Upstream changes to water quality include sedimentation from bank erosion, nutrient enrichment from leaching of flooded material, and changes in thermal regime due to shorter water residence times and less mixing Baxter Perhaps one of the most significant effects of forming upstream reservoirs is the release of methyl mercury, a strong vertebrate neurotoxin, into water Tremblay et al. Methyl mercury is of particular concern in the boreal zone because of the high density of organic matter deposits found in wetlands, and riparian areas, which when combined with naturally occurring or anthropogenically deposited mercury and flooding induced anoxic conditions result in ideal conditions for mercury methylation Kelly et al.

The decomposition of organic matter in flooded lands, particularly wetland soils in reservoirs, fuels the microbial methylation of inorganic mercury to methyl mercury Hall et al. Impoundments increase the surface area of potential mercury methylation by imposing anoxia over the entire flooded area and by facilitating the exchange of nutrients and methyl mercury between the ground surface and the surface water Heyes et al. Ecosystem-scale experiments from the Experimental Lakes Area have improved our understanding of mercury dynamics in reservoirs e. Louis et al.

Flooding of newly created reservoirs creates more methyl mercury than flooding of existing lakes Rosenberg et al. Flooding of wetland areas is more detrimental than flooding of upland areas since the higher concentration of organic matter produces methyl mercury for longer periods than flooding of upland areas St.

In a flooding experiment in boreal upland forests, Hall et al. The initial pulse of methyl mercury production in all experimental reservoirs lasted for two years, after which net demethylation began to reduce the pools of methyl mercury in the reservoirs, but not back to levels found prior to flooding Hall et al. Many of the impacts caused by conventional hydroelectric dams on the streams below them are the reverse of those produced on the reservoirs above them Baxter Attenuated spring flows reduce organic matter and nutrient loading to downstream waters during biologically active periods, ultimately influencing coastal productivity Rosenberg et al.

Other downstream impacts include altered water temperature regimes cooler in the summer and warmer in the winter and increased turbidity due to sediment inputs from erosion Baxter As for other types of hydroelectric power generation, run-of-the-river has few impacts on water quality, allowing sediment to pass through relatively unimpeded Kondolf Thermal power generating stations have impacts on water quality, with the primary concerns related to elevated temperatures of discharge waters and potential pollution from corrosion-control products used in cooling waters Donahue et al.

Madden et al. Although no boreal specific values could be found, this effect could be larger in northern ecosystems where intake temperatures would be lower, particularly in the winter. These thermal effects may be quite localized, but may impact lake stratification and other chemical and biological processes Baxter ; Environment Canada In the United States, thermal regulations have caused a shift in the design of new cooling systems, from once-through cooling systems that discharge heat back into water sources, to cooling systems that evaporate water with towers and ponds that alleviate the thermal pollution but result in increased water consumption due to evaporation Smith and Tirpak Thermal power generation, particularly with coal-fired generating stations, also result in atmospheric emissions of pollutants that may be deposited on local water bodies, or enter the airshed to be subsequenty deposited on downwind water bodies.

The impact of the pollutant emission and deposition is similar to that described for other resource industries see Section 3. Donahue et al. Pollution abatement technologies will become increasingly important, particularly if increased thermal power generating capacity in Alberta is met by expansion of the coal-burning industry Donahue et al.

Electric power generation has differential impacts across the boreal zone. With high topographic relief and wetter climates, the eastern and cordilleran parts of the boreal zone are ideal for hydroelectric power generation, while flatter and drier areas of west-central part of the boreal zone are dependent primarily on thermal power generation. Thus, the specific impacts of these different technologies will be manifested in the areas in which they occur.

There are currently approximately 55 thermal power generation stations across the boreal zone, mostly in Alberta and the Northwest Territories. An increasing demand for cleaner power will likely lead to a decline in fossil fuel based thermal generating stations creating an energy gap that will likely to be filled by hydroelectric power generation based on global trends Kumar et al.

Northern rivers in the boreal zone hold the most remaining potential for large-scale hydroelectric power development in Canada Fig. A large number of new conventional hydroelectric power developments have already been identified across the boreal zone Environment Canada ; Fortin and Collu Although run-of-the-river installations are more environmentally friendly, their low capacity output is likely to limit their use to meeting specialized local power demands. After creating a probability surface to map areas most suitable for frac sand mine occurrence, I developed neutral landscape models from which to compare actual mine distributions in zoned and unzoned areas at three different spatial extents.

Mines were significantly clustered in unzoned jurisdictions at the statewide level and in 7 of the 8 counties with at least three frac sand mines and some unzoned land. Subsequent regression analyses showed mine prevalence to be uncorrelated with land value, tax rate, or per capita income, but correlated with remoteness and zoning. The predicted mine count in unzoned townships was over two times higher than that in zoned townships.

However, the county with the most mines by far was under a county zoning ordinance, perhaps indicating industry preferences for locations with clear, homogenous rules over patchwork regulation. Rural communities can use the case of frac sand mining as motivation to discuss and plan for sudden land-use predicaments, rather than wait to grapple with unfamiliar legal processes.

Shifting markets can cause unexpected, stochastic changes in rural landscapes that may take local communities by surprise. Rural communities can use the case of frac sand mining as motivation to discuss and plan for sudden land-use predicaments, rather than wait to grapple with unfamiliar legal processes during a period of. Removal method of radium in mine water by filter sand. We observed that filter sand with hydrated manganese oxide adsorbed radium in the mine water safely for long time.

The removal method of radium by filter sand cladding with hydrated manganese oxide was studied. The results showed that radium was removed continuously and last for a long time from mine water with sodium hypochlorite solution by passing through the filter sand cladding with hydrated manganese. Only sodium hypochlorite solution was used. When excess of it was added, residue chlorine was used as chlorine disinfection. Filter sand cladding with hydrated manganese on the market can remove radium in the mine water.

The removal efficiency of radium is the same as the radium coprecipitation method added with barium chloride. The cost is much lower than the ordinary methods. Oil sands mine planning and waste management using goal programming. Ben-Awuah, E. Mining Optimization Laboratory. A goal programming method was used to plan waste management processes at an oil sands mine.

This method requires the decision maker DM to set goals. Mine planning is used to determine a block extraction schedule that maximizes net present value NPV. Due to land restrictions, tailings facilities are sited within the pit area and dykes are used to contain the tailings. Many of the materials used to construct the dykes come from the mining operation. The mine plan scheduled both ore and dyke material concurrently.

Dykes were constructed simultaneously as the mine phase advanced. A model was used to classify an oil sands block model into different material types. A mixed integer goal programming MIGP method was used to generate a strategic schedule. Block clustering techniques were used to large-scale mine planning projects. The method was used to verify and validate synthetic and real case data related to the cost of mining all material as waste, and the extra cost of mining dyke material. A case study of an oil sands project was used to demonstrate the method.

The study showed that the developed model generates a smooth and uniform strategic schedule for large-scale mine planning projects. Injury experience in sand and gravel mining , This Mine Safety and Health Administration MSHA informational report reviews in detail the occupational injury and illness experience of sand and gravel mining in the United States for Data reported by operators of mining establishments concerning work injuries are summarized by work location, accident classification, part of body injured, nature of injury, and occupation.

Related information on employment, worktime, and operating activity also is presented. Data reported by independent contractors performing certain work at mining locations are depicted separately in this report. For ease of comparison with other metal and nonmetallic mineral mining industries and with coal mining , summary reference tabulations are included at the end of both the operator and the contractor sections of this report. Sand and gravel mine operations and reclamation planning using microcomputers.

The purpose of this study is to focus on the application of microcomputers, also known as personal computers, in planning for sand and gravel mine operations and reclamation at a site in Story County, Iowa. The Arrasmith site, which encompasses an area of about 25 acres, is a relatively small site for aggregate mining. However, planning for the concurrent mine operation and reclamation program at this site is just as critical as with larger sites and the planning process is the same. Oil sands mining and reclamation cause massive loss of peatland and stored carbon.

We quantified the wholesale transformation of the boreal landscape by open-pit oil sands mining in Alberta, Canada to evaluate its effect on carbon storage and sequestration. Contrary to claims made in the media, peatland destroyed by open-pit mining will not be restored. Current plans dictate its replacement with upland forest and tailings storage lakes, amounting to the destruction of over 29, ha of peatland habitat. Landscape changes caused by currently approved mines will release between These losses have not previously been quantified, and should be included with the already high estimates of carbon emissions from oil sands mining and bitumen upgrading.

A fair evaluation of the costs and benefits of oil sands mining requires a rigorous assessment of impacts on natural capital and ecosystem services. Reclamation of prime farmland following mineral sands mining in Virginia. Significant deposits of mineral sands were discovered in Virginia's Upper Coastal Plain in Taken as a whole, these combined results clearly indicate that mining and reclamation of these prime farmlands will lead to a substantial decrease in rowcrop productivity, at least over the initial years following pit closure and reclamation.

For a given crop in a given year, response to topsoiling versus compost addition to the surface varied, and neither treatment appeared superior. Corn and cotton yields on the mined land treatments were reduced despite the application of irrigation. Cotton quality was also adversely affected by the mining reclamation treatments. Results of these controlled experiments are somewhat encouraging. However, the implementation of protocols will be complicated in practice if tailings and slimes cannot be re-blended to generate a reasonably uniform final reclaimed surface.

Efficient management of marine resources in conflict: an empirical study of marine sand mining , Korea. This article develops a dynamic model of efficient use of exhaustible marine sand resources in the context of marine mining externalities. The classical Hotelling extraction model is applied to sand mining in Ongjin, Korea and extended to include the estimated marginal external costs that mining imposes on marine fisheries.

The socially efficient sand extraction plan is compared with the extraction paths suggested by scientific research. If marginal environmental costs are correctly estimated, the developed efficient extraction plan considering the resource rent may increase the social welfare and reduce the conflicts among the marine sand resource users. The empirical results are interpreted with an emphasis on guidelines for coastal resource management policy. Full Text Available One of main problems in freshwater aquaculture development in Indonesia, especially in Java, is unavailability of developing zone.

It is important to find an underutilized area that meets for industrial scale freshwater aquaculture, i. The abandoned mining sand , tin, etc. For example, there are at least 13 water pools with total surface area of ha at 15 km side of Citarum River in Karawang District West Java Province. Mini floating net cages of 1 x 1 x 1. Observed data showed that patin catfish grew from the initial size of 2.

These three species were technically prospective for aquaculture development in the abandoned sand-mining pools. Based on this preliminary study, existing sand and gravel mining regulations in Maine, USA can be inferred to provide some protection to water resources. Sand and gravel deposits are important natural resources that have dual uses: mining for construction material and pumping for drinking water.

How the mining of sand and gravel affects aquifers and change aquifer vulnerability to contamination is not well documented. Mining regulations vary greatly by state and local jurisdiction. This study test metrics to measure the effectiveness of mining regulations. Data from homeowner interviews and field measurements found scant evidence of changes in water quantity.

Water quality analyses collected from springs, streams, ponds and wells indicate that the aquifer was vulnerable to contamination by chloride and nitrate. However, water quality changes can not be related directly to mining activities. Economic impact of world mining. Mining plays a vital role in the economic development of many countries.

Mining also has a positive impact on the economy of many countries. Another impact of mining can be measured in terms of employment opportunities and income generation. Commercial scale mining provides employment and skills transfer to more than 2 million workers. The multiplier effect increases this benefit by a factor of between 2 and 5. This study demonstrates that there are substantial social and economic benefits to the community.

The most positive cases are related to the growth of local small- and micro-enterprise activities. However, mining remains controversial, as true sustainable development is not only a matter of financial flows. Mining has also been associated with a number of economic and social problems. As a result there are questions about the sustainability of the economic outcome of mining. The contribution of mining to sustainable development needs to be considered in terms of economic and technical viability, ecological sustainability and social equity.

To achieve this, governments, mining companies and local communities must work together to address these issues. The conzequence low income of the farmer household in agricultural sector is the increase in their activities as miner of sand and stone. It means for increasing of their household income. However, how important mining role on the increasing of household income has to be studied in deeply. The factual problem is the base for research aims, with the spesific stress on studying socio-economic characteristic of sand and stone miner, and the contribution of the mining income to household income.

Study on sand particles creep model and open pit mine landslide mechanism caused by sand fatigue liquefaction. The sand particles in the sand - rock composite slope of the open pit mine occurs creep deformation and fatigue liquefaction under the action of vehicle load vibration and hydraulic gradient, which causes landslide geological disasters and it destroys the surface environment.

Data from sand creep experiments are used to identify the parameters in the model and to validate the model. The results show that the mechanical model can describe the rotation progress between the sand particles, disclose the negative acceleration creep deformation stage during the third phase, and require fewer parameters while maintaining accuracy. It provides a new creep model considering rotation to analyze sand creep mechanism, which provides a theoretical basis for revealing the open pit mine landslide mechanism induced by creep deformation and fatigue liquefaction of sandy soil.

Sphere impact and penetration into wet sand. We present experimental results for the penetration of a solid sphere when released onto wet sand. We show, by measuring the final penetration depth, that the cohesion induced by the water can result in either a deeper or shallower penetration for a given release height compared to dry granular material. Thus the presence of water can either lubricate or stiffen the granular material. By assuming the shear rate is proportional to the impact velocity and using the depth-averaged stopping force in calculating the shear stress, we derive effective viscosities for the wet granular materials.

Ecohydrology applications to ecosystem reconstruction after oil- sand mining. Oil- sand deposits in northeast Alberta, Canada comprise some of the world's largest oil reserves. Open-pit mining of these resources leads to waste-rock piles, tailings ponds and open pits that must be reclaimed to "equivalent landscape capability", with viable forests and wetlands, using only native vegetation. Understanding ecohydrological processes in natural systems is critical for designing the necessary landforms and landscapes.

A challenge is the cold, sub-humid climate, with highly variable precipitation. Furthermore, there are competing demands, needs or uses for water, in both quantity and quality, for reclamation and sustainability of forestlands, wetlands and end-pit lakes. On average there is a potential water deficit in the region, yet wetlands cover half of the undisturbed environment. Water budget analyses demonstrate that, although somewhat unpredictable and uncontrollable, the magnitude and timing of water delivery largely control water storage and conservation within the landscape.

The opportunity is to design and manipulate these reconstructed landscapes so that water is stored and conserved, and water quality is naturally managed. Heterogeneous geologic materials can be arranged and layered, and landforms sculpted, to minimize runoff, enhance infiltration, and promote surface and subsurface storage. Similarly, discharge of poor quality water can be minimized or focused.

And, appropriate vegetation choices are necessary to conserve water on the landscape. To achieve these ends, careful attention must be paid to the entire water budget, the variability in its components, interconnections between hydrologic units, in both space and time, and coupled vegetation processes. To date our knowledge is guided primarily by natural analogues.

To move forward, it is apparent that numerous priorities and constraints, which are potentially competing, must be addressed. These include geotechnical and operational requirements, material limitations or excesses. Impacts and mitigations of in situ bitumen production from Alberta oil sands.

Does this impending development threaten the local ecosystem? A quantitative account is given of the principal impacts of in situ oil sands development in Alberta. Impacts on land habitats , water, and air are considered in terms of local capacity, global benchmarks, and comparisons to alternative renewable technologies. Improvements due to new solvent-additive technology are highlighted.

Sand impaction of the small intestine in eight dogs. To describe signalment, clinical findings, imaging and treatment of intestinal sand impaction in the dog. Medical records of dogs with radiographic evidence of small intestinal sand impaction were reviewed. Sand impaction resulting in small intestinal obstruction was diagnosed in eight dogs.

All dogs presented with signs of vomiting. Other clinical signs included anorexia, lethargy and abdominal pain. Radiographs confirmed the presence of radio-opaque material consistent with sand causing distension of the terminal small intestine in all dogs.

Four dogs were treated surgically for their impaction and four dogs were managed medically. Seven of the eight dogs survived. Both medical and surgical management of intestinal sand impaction in the dog can be effective and both afford a good prognosis for recovery. Economic deposits of heavy mineral sand were identified in the late 's under prime farmland along the Upper Coastal Plain of Virginia.

Experiments were established on two mine pits representing two likely pit closure scenarios; regrading the surface with unprocessed subsoil Pit 1 or filling to the surface with processed material Pit 3. To evaluate topsoil replacement vs. Instream sand and gravel mining : Environmental issues and regulatory process in the United States. Sand and gravel are widely used throughout the U. Fisheries biologists often find themselves involved in the complex environmental and regulatory issues related to instream sand and gravel mining.

This paper provides an overview of information presented in a symposium held at the midyear meeting of the Southern Division of the American Fisheries Society in San Antonio, Texas, to discuss environmental issues and regulatory procedures related to instream mining. Conclusions from the symposium suggest that complex physicochemical and biotic responses to disturbance such as channel incision and alteration of riparian vegetation ultimately determine the effects of instream mining.

An understanding of geomorphic processes can provide insight into the effects of mining operations on stream function, and multidisciplinary empirical studies are needed to determine the relative effects of mining versus other natural and human-induced stream alterations.

Mining regulations often result in a confusing regulatory process complicated, for example, by the role of the U. Army Corps of Engineers, which has undergone numerous changes and remains unclear. Dialogue among scientists, miners, and regulators can provide an important first step toward developing a plan that integrates biology and politics to protect aquatic resources. Full Text Available The conzequence low income of the farmer household in agricultural sector is the increase in their activities as miner of sand and stone. This research was carried out in Progo catchment area, Yogyakarta Special Region.

Survey method was employed by data collecting from respondents. The respondents are head of households HH working as sand and stone miner. Sampling technique was proportionally simple random sampling in which HH was taken as respondents sample. They were representatives of upper part, middle part, and lower part of Progo catchments area.

Data on socio-economic structure of the household and household income were collected by mean of structured interview. Data analysis was performed through descriptive technique in which frequencies and cross tabulation varians statistic, and multiple regression analysis were mostly used. The research shows that there are relatively similarities on socio-economic characteristic of sand and stone miners, between at lower part, middle part with upper part of Progo catchments area.

Landless farmers who land own less than m2 characterize them. The most of them are male, withlow formal education, and as small family 4 people evey HH. Some of them have been as sand and stone miners for more than 4 years. Generally, they work less than 8 hours for mining every day. This research is also finding that the income of the sand and stone miners are seasonal. The averages of mining income on dry season Rp , per month.

Considerations when ranking stochastically modeled oil sands resource models for mining applications. Etris, E. Alberta's Athabasca oil sands deposit has been targeted as a major resource for development. Bitumen recovery operations fall into 2 categories, namely mining and in situ operations. Mining recovery is done above ground level and consists of open pit digging, disaggregation of the bitumen-saturated sediment through crushing followed by pipeline transport in a water-based slurry and then separation of oil, water and sediment.

In situ recovery consists of drilling wells and stimulating the oil sands in the subsurface with a thermal treatment to reduce the viscosity of the bitumen and allow it to come to the surface. Steam assisted gravity drainage SAGD is the most popular thermal treatment currently in use. Resource models that simulate the recovery process are needed for both mining and in situ recovery operations. Both types can benefit from the advantages of a stochastic modeling process for resource model building and uncertainty evaluation.

Stochastic modeling provides a realistic geology and allows for multiple realizations, which mining operations can use to evaluate the variability of recoverable bitumen volumes and develop mine plans accordingly. This paper described the processes of stochastic modelling and of determining the appropriate single realization for mine planning as applied to the Fort Hills oil sands mine which is currently in the early planning stage.

The modeling exercise was used to estimate the in-place resource and quantify the uncertainty in resource volumes. The stochastic models were checked against those generated from conventional methods to identify any differences and to make the appropriate adaptations. The radiological impact of past and present practices of the mineral sands industry in Queensland. It is shown that the introduction of uniform Australian national Codes of Practice for radiation protection in the mining and milling of radioactive ores in the early 's has led to the mining and health regulatory authorities implementing the provisions of the Codes.

There are guidelines for screening the radioactivity of tailings released into the environment and some products for industrial use. Future activities by the regulatory authorities and industry will involve an optimisation of radiation protection, ongoing remedial programs, register of data about contaminated lands and assessments of the environmental, occupational and the public radiological impacts from downstream processing of mineral sands.

The latter involves synthetic rutile, zircon flour, rare earth and refractory technologies. Disposal of radioactive waste from mining and processing of mineral sands. All mineral sands products contain the naturally radioactive elements uranium and thorium and their daughters. The activity levels in the different minerals can vary widely and in the un mined state are frequently widely dispersed and add to the natural background radiation levels.

Following mining , the minerals are concentrated to a stage where radiation levels can present an occupational hazard and disposal of waste can result in radiation doses in excess of the public limit. Chemical processing can release radioactive daughters, particularly radium, leading to the possibility of dispersal and resulting in widespread exposure of the public. The activity concentration in the waste can vary widely and different disposal options appropriate to the level of activity in the waste are needed.

Disposal methods can range from dilution and dispersal of the material into the mine site, for untreated mine tailings, to off site disposal in custom built and engineered waste disposal facilities, for waste with high radionuclide content. The range of options for disposal of radioactive waste from mineral sands mining and processing is examined and the principles for deciding on the appropriate disposal option are discussed.

The range of activities of waste from different downstream processing paths are identified and a simplified method of identifying potential waste disposal paths is suggested. Economic impacts of Alberta's oil sands , volume 1. In , the international media recognized Alberta's oil sands as part of the global oil reserves, thereby establishing Canada as second to Saudi Arabia as potential oil producing nations. The economic impacts of Alberta's oil sands industry on economies were assessed at regional, provincial and international levels for the to period. A customized input-output model was used to assess economic impacts , which were measured in terms of changes in gross domestic product; employment and labour income; and, government revenues.

Cumulative impacts on employment by sector and by jurisdiction were also presented. The impact of the oil sands industry on local employment was also evaluated. It was shown that activities in the oil sands industry will lead to significant economic impact in Alberta, Ontario, Quebec and the rest of Canada. Alberta's local economy would be the main beneficiary of oil sands activities with nearly 3. Another 3 million person years employment would be created in other Canadian provinces and outside Canada during the same time period. A sensitivity analysis on the responsiveness to oil prices and the removal of various constraints incorporated in the main analysis was also presented.

The federal government will be the largest recipient of revenues generated to to oil sands activities. This first volume revealed the results of the study while the second volume includes the data and detailed results. Oil sands production now accounts for 1 out of every 2 barrels of supply in Western Canada. It is anticipated that Alberta's oil sands sector will experience significant growth over the next few decades. This paper provided an outline of the challenges and economic impacts resulting from oil sands development in Canada. Alberta's oil sands reserves are estimated at billion barrels that are deemed economically recoverable using current technology.

At current production levels, reserves will sustain production of 2. Numerous companies hold leases and are planning new projects. A number of recent advances in oil sands technology are expected to further reduce costs as development matures. A royalty and tax regime that provides long-term fiscal certainty is a key factor that supports current oil sands growth forecasts.

The CERI study has indicated that economic spinoffs from oil sands development relate to employment generated outside of Alberta, and that the largest percentage of government revenue accrues to the federal government. However, development may be constrained because the pace of growth in the sector may exceed underlying infrastructure related to roads, housing and municipal services. An adequate workforce of qualified trades and technical and professional people is also crucial. Several pipeline projects have been proposed to deliver oil sands crudes to new markets over the next decade.

It was concluded that the billions of dollars invested in oil sands in Alberta will contribute to the economic prosperity of the entire country. Keywords: Solid mineral, Impact assessment, Mined -out area utilization, Metal mining to the aid of the oil sands? Lateral opportunities in industrial cross-breeding.

This paper demonstrated how oil sands operations can benefit from supporting innovative low cost metal mining to enhance their eco-footprint. Northeast Alberta contains large accumulations of recoverable metals, hosted in metal bearing black shales. Immense low grade polymetallic zones were discovered in but could not be exploited with existing recovery technologies. However, significant advances in bioleaching of metals from polymetallic black shale deposits have propelled this new deposit type to the forefront over the past 5 years as a long term future source of metals.

Dumont Nickel Inc. The projects present opportunities to develop low footprint metal mines , to use run-of-river hydro, to harvest waste heat, and to combine local technologies to create a new valuable industry independent of energy markets. Radionuclides and radiation doses in heavy mineral sands and other mining operations in Mozambique.

Sites at the littoral of Mozambique with heavy mineral sands exploited for ilmenite, rutile and zircon and inland mineral deposits exploited for tantalite, uranium and bauxite were surveyed for ambient radiation doses, and samples were collected for the determination of radionuclide concentrations. Radiation exposure of workers in mining facilities is likely to occur at levels above the dose limit for members of the public 1 mSv y -1 and therefore radiation doses should be assessed as occupational exposures.

Local populations living in these regions in general are not exposed to segregated minerals with high radionuclide concentrations. However, there is intensive traditional mining and a large number of artisan miners and their families may be exposed to radiation doses exceeding the dose limit. A radiation protection programme is therefore needed to ensure radiation protection of the public and workers of developing mining projects. However, there is intensive artisanal mining and a large number of artisanal miners and their families may be exposed to radiation doses exceeding the dose limit.

Impacts of Canada's uranium mining industry. This study examines economic and environmental impacts of uranium mining in Canada and compares these impacts with those of other extractive and energy industries. The uranium industry generates taxes and royalties, income, employment, foreign exchange earnings, security of energy supply, and technological spinoffs. The indirect impacts of the industry as measured by employment and income multipliers are lower than those for other types of mining and comparable to oil and gas because of the high proportion of costs withdrawn from the economy in the form of taxes and operator margin.

Social costs are primarily occupational hazards. Uranium mining probably has a lower non-health environmental impact than other mining industries due to much smaller throughputs and transportation requirements. Residents of the area surrounding the mine bear a disproportionate share of the social costs, while non-residents receive most of the benefits. Environmental impact of uranium mining and milling. The author introduces the subject with an overview of the regulatory requirments and philosophy applied to uranium mines and mills. The special attention given to tailings management is highlighted, and a discussion of the basic environmental concerns is concluded with an itemizing of the main tasks facing the AECB.

The extent of the environmental impact of uranium mining , milling and waste management is illustrated with specific details pertaining to mines in the Elliot Lake area. The author concludes that the impact on the ground and surface water system is not alarming, and the impact on air quality is not significant beyond a few hundred metres from the mining facilities. The publicly perceived impact is discussed, followed by a rationale for the continued licensing of new uranium mining operations complete with tailings management facilities.

Cultural keystone species CKS shape the cultural identify of people through the roles they have in diet, material and spiritual practices. The use of the CKS concept is regarded as a method of addressing linked social and ecological issues. This paper presented the results of using the CKS model in the indigenous community of Fort McKay, Alberta to address, social, ecological and spiritual values in regional mine -land reclamation. Fort McKay is at the epicenter of the existing mine developments.

Its residents regard human and environmental health to be be linked and therefore experience the effects of development and subsequent reclamation on both cultural and ecological levels. The community is actively engaged in working with the local mining companies on issues of mine reclamation design. In order to hold meaning to the local people, oil sand operators used the CKS concept in their reclamation efforts to take into account ecological functionality and also address the linked social factors.

Five CKS were identified through a literature review and extensive community interviews. The list includes moose, cranberry, blueberry, ratroot and beaver. These 5 CKS were used to focus discussions and make recommendations for relevant land reclamation within Fort McKay traditional territory.


  • Killing the Dream: James Earl Ray and the Assassination of Martin Luther King, Jr..
  • Stanford Libraries?
  • Environmental Reviews!

The project has influenced the way both the community and oil sands operators engage with reclamation. Lessons learned from this process will help direct reclamation activities on other portions of traditional territory, while offering guidance to other regional developers for addressing cultural values in reclamation on their leases.

Spontaneous revegetation vs. Uranium mining : Environmental and health impacts. Producing uranium in a safe and environmentally responsible manner is important not only to the producers and consumers of the product, but also to society at large. Given expectations of growth in nuclear generating capacity in the coming decades - particularly in the developing world - enhancing awareness of leading practice in uranium mining is important.

This was the objective of a recent NEA report entitled Managing Environmental and Health Impacts of Uranium Mining , providing a non-technical overview of the significant evolution of uranium mining practices from the time that it was first mined for military purposes until today. Assessment of source material U and Th in exploration, mining , processing of zircon sand in Central Kalimantan.

From to , according to data released by the Commerce Department, the volume of zircon sand and concentrates exports has increased highly. One of many locations in Indonesia that widely available zircon sand is Kalimantan island. For example, Central Kalimantan Province in to exports about 51, tones up to 79, tones of zircon sand annually. The concentration of source material in the zircon sand is important to be known because the presence of natural radioactive U and Th in zircon sand has the potential radiation hazard.

Therefore it is necessary to conduct an assessment the potential reserves related to the source material contained in the zircon sand and radiation safety that are applied in the process of mining or processing of zircon sand. In this paper the location of mining and processing of zircon sand is restricted to the province of Central Kalimantan. Environmental impacts of mining : monitoring, restoration and control.

Contains 12 chapters with the following titles: mining and the environment; surface coal mining with reclamation; reclamation and revegetation of mined land; the acid mine drainage problem from coal mines ; acid rock drainage and metal migration; hydrologic impact ; erosion and sediment control; wetlands; blasting; mining subsidence; postmining land use; environmental effects of gold heap-leaching operations.

Full Text Available Lubricant contaminants cause severe problems to machines. Substantial research has been conducted to study the impact of such contaminates on the tribological performance of lubricated contacts. The current study investigates the tribological behavior of contaminated lubricated contacts; the contaminants considered in this research are sand particles. The effect of the sand particles concentration levels on friction and wear of a tribological system under sliding contact was studied.

The experimental program was carried out using an in-house built ball on disc machine at room temperature, constant normal load, constant speed, constant running time and constant travelling distance. Results showed that both friction coefficient and wear volume of the contacting surfaces are dependent on the concentration level of the sand particles.

Both friction coefficient and wear volume increased by increasing the sand particles concentration. SEM was utilized to study the wear mechanisms of the contacting surfaces, it was found that the dominant wear mechanism in all cases was abrasive wear. Newest oil sands mine on the horizon : Fort McMurray's next megaproject. The newly approved Horizon mine project and on-site upgrader project will be one of Canada's largest oil sands operation. The site for the facility is 70 km north of Fort McMurray, Alberta. Drilling has revealed an in-place resource of 16 billion bbl of bitumen, of which 6 billion bbl is potentially recoverable using existing mining technologies.

In situ recovery potential on the western parts of the lease will be used to obtain additional resources. Horizon is owned by Calgary-based Canadian Natural Resource Limited, the second largest oil and gas company in Canada. The mine will be a truck and shovel operation, mining , tonnes of oil sand daily from 2 main pits.

The clean, diluted bitumen from the froth treatment plant will be sent to an onsite upgrader that will use delayed coking technology to recover 99 per cent of the sulphur using a tail gas cleanup unit. All of the product will be hydrotreated. In the first phase, the mine will produce sweet synthetic crude oil by the second half of at a daily rate of , bbl. The tailings during the first phase will be sent to a conventional tailings pond. A non-segregating tailings disposal method will be considered for the second phase to reduce the size of the required tailings pond and to leave less of an environmental footprint.

The Horizon leases include traditional lands of several First Nation bands. Canadian Natural is involving Aboriginal communities in the project through employment and consultation for traditional environmental knowledge. During peak. Underground coal mine subsidence impacts on surface water. This paper reports that subsidence from underground coal mining alters surface water discharge and availability. The magnitude and areal extent of these impacts are dependent on many factors, including the amount of subsidence, topography, geology, climate, surface water - ground water interactions, and fractures in the overburden.

One of the most significant surface water impacts occurred in July near West Pittston, Pennsylvania. Subsidence in the Knox Mine under the Coxton Yards of the Lehigh Valley Railroad allowed part of the discharge in the Susquehanna River to flow into the mine and create a crater feet in diameter and feet deep.

These books may interest you

Fourteen railroad gondola cars fell into the hole which was eventually filled with rock, sand , and gravel. Other surface water impacts from subsidence may include the loss of water to the ground water system, the gaining of water from the ground water system, the creation of flooded subsidence troughs, the increasing of impoundment storage capacity, the relocation of water sources springs , and the alteration of surface drainage patterns.

Summary of environmental impact assessment for the Syncrude Canada Ltd. Aurora Mine. A summary of the environmental impact assessment for the Syncrude's proposed Aurora Mine was provided. Two mining areas will be opened. Aurora Mine North, located on oil sands leases 10, 12 and 34 will open first followed by the opening of Aurora Mine South, located on Lease Each mining area will contain two extraction facilities, each capable of producing 6. The areas of land that will be disturbed by development of the Aurora Mines will total 15, hectares.

The preferred pipeline, roadway and utility corridor and river crossing to be used for the Mine are shown. Production of SO 2 and NO x emissions from the Aurora Mine is expected to be very low, nevertheless, the cumulative effects of emissions from the mines will be addressed in the context of emissions from the existing or proposed oil sand facilities in the area. Oil sands tailings technology : understanding the impact to reclamation.

This paper discussed tailings management techniques at oil sands mines and their effects on reclamation schedules and outcomes. The layer of mature fine tailings MFT that forms in tailings ponds does not settle within a reasonable time frame, requiring more and larger tailings ponds for storing MFT. Consolidated tailings CT technology was developed to accelerate the consolidation of MFT, although the process nonetheless takes decades. CT is produced from mixing tailings sand , gypsum, and MFT to create a mixture that will consolidate more quickly and release water.

However, CT production is tied to the extraction process, making it applicable only when the plant is operational, and a precise recipe and accurate injection are required for CT to work. In tailings reduction operations TRO , a new approach to tailings management, MFT is mixed with a polymer flocculant, deposited in thin layers, and allowed to dry. TRO has a significant advantage over CT in that the latter takes up to 30 years to consolidate to a trafficable surface compared to weeks for TRO.

TRO allows MFT to be consumed more quickly than it is produced, reducing need to build more tailings ponds, operates independent of plant operations, accelerates the reclamation time frame, and offers enhanced flexibility in final tailings placement sites. TRO also creates a dry landscape, to which well established reclamation techniques can be applied. Dried MFT is a new material type, and research is exploring optimum reclamation techniques.

Seasonal impact of quarry mining effluent discharge impacted soils This study was designed to assess the impact quarry mining effluent discharge impacted soil on growth parameters and phytochemical constituents of edible vegetables. Three quarry mining sites were used for the study that covered wet and dry seasons.

Plant growth such as plant height, leaf area, internodes and plant Final environmental impact statement. Marquez uranium mine. As one of many activities TVA has undertaken to ensure an adequate supply of uranium for these plants, TVA has proposed to underground mine , through its operator, the uranium deposits located in the Canon de Marquez in McKinley County, New Mexico. Construction and operation of the underground mine would be expected to have the following environmental effects: a a temporary change in land use for The no action alternative and alternatives for securing uranium ore by other methods were considered but were found insufficient to meet TVA objectives.

None of the alternatives explored were environmentally preferable. TVA also evaluated site specific alternatives including the following: different shaft and support building siting, mining techniques, and reclamation options. Key performance indicators for electric mining shovels and oil sands diggability. A shovel performance monitoring study was undertaken in two oil sands mines operated by Syncrude Canada Ltd. One year of shovel performance data along with geological, geotechnical, and climatic data were analyzed. Analysis of performance data along with digital video records of operating shovels indicated that hoist and crowd motor voltages and currents can be used to identify the beginning and the end of individual dig cycles.

A dig cycle identification algorithm was developed. Performance indicators such as dig cycle time, hoist motor energy and power, and crowd motor energy and power were determined. The shovel performance indicators provide important insight into how geology, equipment and operators affect the digging efficiency. The hoist motor power is a useful key performance indicator for assessing diggability.

Hoist motor energy consumption per tonne of material excavated and the number of dig cycles required for loading a truck can be useful key performance indicators for assessing operator performance and productivity. Analysis of performance data along with operators team schedules showed that the performance of a shovel can be significantly influenced by the operator's digging technique while digging uniform material.

Shovel type and dipper teeth configuration can also influence the power draw on electrical motors during digging. There is no common agreement existing on the influence of bitumen content on oil sands diggability. By comparing the hoist motor power consumption, it was found that the rich ore was more difficult to dig than the lean ore. Similarly, estuarine ore was more. As a result, new facilities including tailings management areas are designed and developed to meet a high standard. The impact of the mines and tailings areas in the Elliot Lake area on ground and surface waters and air quality is discussed in detail.

Literature search on the environmental impacts of tar sands operations. An extensive review is presented of the literature on the chemistry and biological impacts of current and potential effluents and discharges from oil sands plants on the Athabasca River. The pollutant compounds of interest included polycyclic aromatic hydrocarbons, methyl homologues and metabolites, polycyclic aromatic sulfur heterocycles, polycyclic aromatic nitrogen heterocycles, and naphthenic acids.

Topics of interest include chemical methods for identifying and quantitating the above compounds and their metabolites, their sources and release rates, their toxicity to native fish of the Athabasca system, and their degradation in the natural environment. Microbial turnover and incorporation of organic compounds in oil sand mining reclamation sites. Microorganisms play an important role in the development of new soils and in the reclamation of disturbed landscapes.

Especially in hydrocarbon-contaminated soils their ability to degrade organic matter and pollutants makes them essential to re-establish full ecosystem functionality. Microbes are also involved in the mobilization of nutrients for plant growth and in the production of greenhouse gases.

Reclamation sites from oil sand mining activities in Alberta, Canada, contain residual bitumen as well as other hydrocarbons. So, these areas provide a great opportunity to study microbial degradation of residual contaminants from oil sand. To get an impression of degradation rates as well as metabolic pathways, incubation experiments were performed in the lab.

We measured microbial turnover catabolic metabolism and incorporation anabolic metabolism rates of different common organic compounds in samples from differently treated reclamation sites - with plant cover and without plant cover. About 10 g of sample material was suspended in 10 mL of a solution that mimics the in-situ concentration of dissolved ions. Radioactively labelled 14C-acetate was added as a common substrate, whereas 14C-naphthenic acid was chosen to investigate the microbial community's capability to utilize a typical hydrocarbon pollutant in oil sand tailings as a nutrient source.

To test for the influence of fertilizers on microbial activity, phosphate, nitrate and potassium were added to some samples in different combinations. Incubations were run over two different time periods 7 and 14 days. At the end of each incubation experiment, the amount of produced 14CO2, 14C incorporated into the cells and the remaining unreacted 14C in the slurry were measured. First results show that most of the added 14C-acetate is used for respiration as it is mostly released as 14CO2. Vulnerability of soils towards mining operations in gold-bearing sands in Chile.

The contamination levels in handicraft mining , despite less production and processing less equipment, have high repercussions upon the environment in many cases. High-grade ore extraction, flotation, gravity concentration, acid leaching cementation and mercury amalgamation are the main metallurgical technologies employed.

Gold recovery involving milling and amalgamation appears to the most contamination source of mercury. This research work is only a starting point for carrying out a risk probability mapping of pollutants of the gold bearing sands.