Savage River Research Articles

Some Observations from a Summer Trip to Alaska

Last summer my wife and I went to Alaska for a couple of weeks. In my nearly 40 years of work with the U.S. Fish and Wildlife Service I never had the opportunity to experience Alaska’s wetlands, so I had to do it in retirement — one item on my bucket list. We started our trip in Anchorage and our first stop with the rental car was Potter Marsh which has a great boardwalk system traversing the marsh. To our surprise after walking just 100 yards, we saw a moose feeding in the shallow water...what a sight at our first stop. We then went to Seward and along the way stopped at the Alaska Wildlife Conservation Center and Exit Glacier. When back in Anchorage we stopped at 49th State Brewing where I had two pints of a delicious imperial stout — “Candy Bar” — brewed with peanuts, chocolate, and caramel...perfect for my sweet tooth (sorry but the beer was just so good I have to give it a shout-out). We also visited a high school classmate who was a teacher in Anchorage and spent a day in Talkeetna where we spoke with Aurora Dora, a local photographer who has captured some amazing images of the Aurora Borealis (check out images on her website: https://auroradora.com/). Here we also sampled some birch syrup made from White or Paper Birch (Betula papyrifera var. humilis and B. neoalaskana). On Day 3 we began our Princess land-sea cruise tour as we headed north to Denali for a couple of days and then took the scenic train to Whittier (great views of Alaska’s wetlands on the way, despite the rain) and then to various ports via ship. I was hoping to see some bears in Denali and other places, but the salmon were not yet running, so bears were out of sight although I did see one running across a meadow at some distance. I also saw a few along with other animals common to the state at the Alaska Wildlife Conservation Center where they rescue injured/orphaned wildlife. Some high points of the trip were seeing Denali in all its glory, a female moose with calf at Horseshoe Lake, wildflowers in bloom along the Savage River Trail and the Savage Alpine Trail (exhausting but great time for wildflower photography), a hike across a local bog at Hoonah (Icy Strait Point), a hike through a temperate rain forest (Tongass National Forest) to Mendenhall Glacier, and seeing Humpback Whales (Megaptera novaeangliae) bubblenet feeding in Auke Bay, plus views of a few other glaciers and whales during the cruise. If you don’t know what bubble-net feeding is ... check out this website: https:// www.youtube.com/watch?v=z00G0RxeSP0. There’s still more to see in Alaska, so we’ll probably be heading back in late summer 2025 to travel inland. Here’s some mostly wetland-centric images from the trip.

Genetic Structure of Maryland Brook Trout Populations: Management Implications for a Threatened Species

AbstractBrook Trout Salvelinus fontinalis have declined across their native range due to multiple anthropogenic factors, including landscape alteration and climate change. Although coldwater streams in Maryland (eastern United States) historically supported significant Brook Trout populations, only fragmented remnant populations remain, with the exception of the upper Savage River watershed in western Maryland. Using microsatellite data from 38 collections, we defined genetic relationships of Brook Trout populations in Maryland drainages. Microsatellite analyses of Brook Trout indicated the presence of five major discrete units defined as the Youghiogheny (Ohio), Susquehanna, Patapsco/Gunpowder, Catoctin, and Upper Potomac, with a distinct genetic subunit present in the Savage River (upper Potomac). We did not observe evidence for widespread hatchery introgression with native Brook Trout. However, genetic effects due to fragmentation were evident in several Maryland Brook Trout populations, resulting in erosion of diversity that may have negative implications for their future persistence. Our current study supplements an increasing body of evidence that Brook Trout populations in Maryland are highly susceptible to multiple anthropogenic stresses, and many populations may be extirpated in the near future. Future management efforts focused on habitat protection and potential stream restoration, coupled with a comprehensive assessment framework that includes genetic considerations, may provide the best outlook for Brook Trout populations in Maryland.

A Geometallurgical Approach to Tailings Management: An Example from the Savage River Fe-Ore Mine, Western Tasmania

At the Old Tailings Dam (OTD), Savage River, Western Tasmania, 38 Mt of pyritic tailings were deposited (1967 to 1982) and have since been generating acid and metalliferous drainage (AMD). Mineral chemistry analysis confirmed high concentrations of refractory cobalt in pyrite (up to 3 wt %). This study sought to determine, through a series of bench scale tests, if Co could be liberated using biohydrometallurgical techniques. Four bulk tailings samples were collected across the OTD, from up to 1.5 m depth, targeting three sulphide-bearing facies. The study was conducted in four stages: (1) bacterial adaption using BIOX® bacteria; (2) biooxidation optimization with pH, temperature and Fe medium parameters tested; (3) flotation test work to produce a sulphide concentrate followed by biooxidation; and (4) Fe and Co precipitation tests. The BIOX® culture adapted to the bulk composite (containing 7 wt % pyrite) in ~10 days, with biooxidation occurring most efficiently at pH 1.5–1.6 and 40 °C whilst the Fe medium concentration was identified as a less-controlling parameter. Flotation produced a 71% pyrite concentrate with total oxidation occurring after 14 days of biooxidation with 99% of Co leached. At pH 3, Co was effectively separated from Fe, however Ni and Cu were also present in the pregnant liquor solution and therefore required refining before production of cobalt hydroxide, the intermediate saleable product. This study shows that adopting a geometallurgical approach to tailings characterisation can identify if mine waste has commodity potential and how best to extract it therefore unlocking the potential for unconventional rehabilitation of AMD affected sites.

Mercury Concentrations in Northern Two-Lined Salamanders from Stream Ecosystems in Garrett County, Maryland.

The purpose of this study was to increase our understanding of the bioaccumulation of mercury in northern two-lined salamanders (Eurycea bislineata bislineata) in freshwater stream ecosystems. We collected 111 adults and 131 larval northern two-lined salamanders from six streams in Garrett County, Maryland. These salamanders were collected in April, July, and September 2010. We measured the size and tissue mercury content in all of these salamanders. We also measured the total and methyl mercury concentrations in stream water on monthly basis from April through December 2010. Averaged over all stream ecosystems, adult northern two-lined salamanders had significantly greater total mercury concentrations than larval salamanders (29.6 vs. 23.8ngg-1). For individual stream ecosystems, the mean tissue mercury contents in adult northern two-lined salamanders were significantly greater than the mean tissue mercury contents in larval northern two-lined salamanders for Bear Pen and Mill Run. Adult and larval salamanders from the Little Savage River and Mud Lick had 1.5-2 times greater mean tissue mercury contents than salamanders in all other streams. These two streams also had significantly greater total and methyl mercury concentrations. Despite their different life-stage feeding behaviors (terrestrial vs. aquatic), the tissue mercury contents of adult (r=0.76) and larval (r=0.79) northern two-lined salamanders were strongly linked to the methyl mercury concentrations in stream water. This implies that northern two-lined salamanders may be a useful bioindicator of mercury pollution in relatively pristine stream ecosystems.

Improved mine waste characterisation through static blended test work

Prediction of the geoenvironmental characteristics of mine waste materials typically relies on the static and kinetic testing of individual waste units. In reality, waste rock piles are heterogeneous landforms containing potentially acid forming (PAF) units juxtaposed with non-acid forming (NAF) units. Despite this, predictive geoenvironmental test work programs rarely characterise blends of waste materials. Through undertaking laboratory-based blended static testing and mineralogical assessments, a first insight into the leachate chemistry of a waste landform can be ascertained. This was tested using three waste units (Type A – alkaline, B – neutral and D – PAF; n=31) obtained from the Savage River mine, Western Tasmania. Seven daughter blend types (1–7; n=42) were prepared using different ratios of the individual waste types, and characterised by acid base accounting and mineralogical techniques. Blend types were NAF when a maximum of 20% of Type D was used, with daughter blend 4 (90% Type A+10% Type D) the most inert when screened against ANZECC (2000) aquatic protection trigger values. This study demonstrates that through first-pass static blended testing, opportunities exist to improve waste-rock handling practices and design NAF waste piles once field trials, involving a range of particle sizes, have been conducted.

Long-term response of surface water acid neutralizing capacity in a central Appalachian (USA) river basin to declining acid deposition

Long-term changes in acid-base chemistry resulting from declining regional acid deposition were examined using data from repeating synoptic surveys conducted within the 275 km2 Upper Savage River Watershed (USRW) in western Maryland (USA); a randomly-selected set of 40 stream reaches was sampled 36 times between 1999 and 2014 to: (1) repeatedly characterize the acid-base status of the entire river basin; (2) determine whether an extensive network of streams of varying order has shown signs of recovery in acid neutralizing capacity (ANC); and (3) understand the key factors controlling the rate of ANC recovery across the river network. Several non-parametric analyses of trends (i.e., Mann Kendall Trend: MKT tests; and Regional Kendall Trend: RKT) in streamwater acid-base chemistry suggest that USRW has significantly responded to declining acid deposition during the study period; the two most robust, statistically significant trends were decreasing surface water SO42− (∼1.5 μeq L−1 yr−1) and NO3− (∼1 μeq L−1 yr−1) concentrations—consistent with observed downward trends in regional wet S and N deposition. Basin-wide decreasing trends in K+, Mg2+, and Ca2+ were also observed, while Na+ concentrations increased. Significant ANC recovery was observed in 10–20% of USRW stream reaches (depending on the p level used), but the magnitude of the trend relative to natural variability was apparently insufficient to allow detection of a basin-wide ANC trend using the RKT test. Watershed factors, such as forest disturbances and increased application of road deicing salts, appeared to contribute to substantial variability in concentrations of NO3− and Na+ in streams across the basin, but these factors did not affect our overall interpretation of the results as a systematic recovery of USRW from regional acidification. Methodologically, RKT appears to be a robust method for identifying basin-wide trends using synoptic data, but MKT results for individual systems should be examined closely (e.g., to identify trends for specific subpopulations).

Mineralogical and geochemical characterization of the Old Tailings Dam, Australia: Evaluating the effectiveness of a water cover for long-term AMD control

Establishing a shallow water cover over tailings deposited in a designated storage facility is one option to limit oxygen diffusion and retard oxidation of sulfides which have the potential to form acid mine drainage (AMD). The Old Tailings Dam (OTD) located at the Savage River mine, western Tasmania contains 38 million tonnes of pyritic tailings deposited from 1967 to 1982, and is actively generating AMD. The OTD was constructed on a natural gradient, resulting in sub-aerial exposure of the southern area, with the northern area under a natural water cover. This physical contrast allowed for the examination of tailings mineralogy and geochemistry as a function of water cover depth across the OTD. Tailings samples (n = 144, depth: ≤ 1.5 m) were collected and subjected to a range of geochemical and mineralogical evaluations. Tailings from the southern and northern extents of the OTD showed similar AMD potential based on geochemical (NAG pH range: 2.1 to 4.2) and bulk mineralogical parameters, particularly at depth. However, sulfide alteration index (SAI) assessments highlighted the microscale contrast in oxidation. In the sub-aerial zone pyrite grains are moderately oxidized to a depth of 0.3 m (maximum SAI of 6/10), under both gravel fill and oxidized covers, with secondary minerals (e.g., ferrihydrite and goethite) developed along rims and fractures. Beneath this, mildly oxidized pyrite is seen in fresh tailings (SAI = 2.9/10 to 5.8/10). In the sub-aqueous zone, the degree of pyrite oxidation demonstrates a direct relationship with cover depth, with unoxidized, potentially reactive tailings identified from 2.5 m, directly beneath an organic-rich sediment layer (SAI = 0 to 1/10). These findings are broadly similar to other tailings storage facilities e.g., Fox Lake, Sherritt-Gordon ZnCu mine, Canada and Stekenjokk mine, Sweden where water covers up to 2 m have successfully reduced AMD. Whilst geotechnical properties of the OTD restrict the extension of the water cover, pyrite is enriched in cobalt (up to 2.6 wt%) indicating reprocessing of tailings as an alternative management option. Through adoption of an integrated mineralogical and geochemical characterization approach for tailings assessment robust management strategies after mine closure can be developed.

Does the spatial arrangement of disturbance within forested watersheds affect loadings of nitrogen to stream waters? A test using Landsat and synoptic stream water data

Remotely sensed maps of forest disturbance provide a powerful tool for predicting spatial and temporal variability in the loading of nitrogen to receiving waters, key data needed for effective watershed management of nutrient pollution. We hypothesize that the spatial arrangement of disturbances within small-forested watersheds can affect N loadings. To test this, we developed schemes for spatially weighting maps of yearly disturbance produced through change analysis of the Landsat Tasseled Cap Disturbance Index (DI), and evaluated the ability of each scheme to predict N concentrations, and subsequently estimated N loads, from forty low-order streams within the Savage River drainage of western Maryland, USA during the 2006–2010 water years, a period encompassing extensive defoliations by gypsy moths (Lymantria dispar). We generated a base scheme of unweighted, watershed averaged change in DI (ΔDI), and five other schemes that weighted ΔDI by either a pixel's flow accumulation value, the distance to the watershed outlet, or proximity to the stream. Over the five years, the flow accumulation scheme tended to perform better than other weighting schemes, and even explained slightly more variability than the base scheme during years of moderate N loads (R2=0.15 vs. 0.03 in 2007 and R2=0.30 vs. 0.18 in 2010). However, this best spatial weighting scheme explained comparable or less variability during the two post-defoliation years with larger N loads (R2=0.43 vs. 0.44 in 2008 and R2=0.31 vs. 0.48 in 2009). Thus, for the purposes of utilizing remote sensing information within watershed management of nutrient pollution, these results suggest that coarse-scale, high temporal frequency data such as MODIS could be well suited for characterizing forest disturbance and predicting the resultant episodic N loads.

Simulating streamflow and the effects of projected climate change on the Savage River, Maryland, USA

The Savage River in western Maryland and its associated reservoir and watershed serves many purposes including recreation, drinking water supply, and auxiliary water supply for Washington DC. Streamflow on the Savage River was modeled using a simple hydrologic model and validated with historical streamflow observations. Future projected climate data were used to drive the model to assess the impact of temperature and precipitation changes on future streamflow. Winter streamflow is projected to increase, while spring, summer, and fall streamflow are projected to decrease. Annual streamflow totals show a slight negative trend over the coming century. Future changes in precipitation are more influential on future streamflow during the winter while temperature may be more important during the summer and fall. On an annual basis, by the year 2098, the impacts of temperature and precipitation will essentially cancel each other out resulting in only a small negative trend in annual streamflow. Increased streamflow during the winter months may not be able to compensate for decreased flow during the remainder of the year which raises concerns about the ability of the reservoir to supply water during future droughts.

Ore Deposits and Metallogenesis of Tasmania

Tasmania contains a broad variety of economic mineral deposits, which includes several that have been known for over a century and are still operating today or were worked in the recent past. The Arthur Lineament, a belt of allochthonous amphibolite, carbonate rocks, psammite and pelite in northwest Tasmania hosts the Savage River magnetite deposit, which is now considered to be a Proterozoic carbonate replacement deposit with affinities to Kiruna-style iron-oxide Cu-Au deposits. The allochthon was formed during an early Cambrian collisional event between an east-facing passive margin sequence and an intraoceanic island arc. Post collisional, proximal submarine volcanism at c. 500 Ma in the Mount Read Volcanics followed and associated mineralisation includes world-class deposits. High grade Zn-Pb-Au-Ag-Cu massive sulfide deposits (e.g., Rosebery and Hellyer) were formed from seawater-dominated hydrothermal fluids. Disseminated Cu-Au-Ag deposits of the Mount Lyell field are associated with broad alteration zones that include phyllosilicate assemblages indicative of a component of oxidised magmatic fluid, as does the Henty Au deposit in the north. Orogenic Au is an important deposit style in northeast Tasmania and includes the Tasmania deposit, Australia's largest single Au reef. Largely post-orogenic granitic magmatism (Lower Devonian-Tournaisian) includes an important Sn-W-base metal ± magnetite mineralising event associated with reduced, fractionated granite in northeast and western Tasmania. World class Sn ± Cu sulfide skarn and vein deposits are the product of interpreted magmatic fluids exsolved from these granitic magmas. The highly unusual disseminated Avebury Ni deposit is associated with granite of this type. World class scheelite skarn deposits on King Island lie in the contact aureole of moderately oxidised, unfractionated Tournaisian granodiorite on King Island.

Relationship of a Landsat cumulative disturbance index to canopy nitrogen and forest structure

Spatially-explicit knowledge of the timing, frequency, and intensity of forest disturbances is essential for forest management, yet little is known about how disturbances such as forest harvests and insect outbreaks might accumulate in their effects over time. Capturing the many forest harvest and insect defoliation events occurring over twenty-five years, we transformed a series of Landsat images into cumulative disturbance maps covering Green Ridge State Forest (GRSF) and Savage River State Forest (SRSF) in western Maryland. These maps summed yearly ΔDI images, which were defined as the change in a yearly tasseled cap disturbance index (DI), relative to a synthetic reference condition map created by finding the minimum DI value for all years. Intensive field-plot surveys and AVIRIS imagery collected during the summer of 2009 provided measurements of forest structure and canopy nitrogen. With these data, we found that while the most recent year's ΔDI had little relation, increases in the cumulative DI were related to decreased field-measured current canopy cover (R2=0.66 at GRSF, 0.67 at SRSF and 0.34 combined) and watershed-averaged AVIRIS canopy N (R2=0.40 at GRSF, 0.57 at SRSF and 0.54 combined). The latter relationship was obscured at the field-plot level of analysis, suggesting that fine scale studies will also need to account for other drivers (e.g. species composition) of variability in canopy N. Nevertheless, our study demonstrates that Landsat time series data can be synthesized into cumulative metrics incorporating multiple disturbance types, which help explain important cumulative disturbance-mediated changes in ecosystem functioning.

Detection of flooding responses at the river basin scale enhanced by land use change

The Georges Creek watershed (area 187.5 km2) in western Maryland (United States) has experienced land use changes (>17% of area) associated with surface mining of coal. The adjacent Savage River watershed (area 127.2 km2) is unmined. Moments of flood frequency distributions indicated that climatic variability affected both watersheds similarly. Normalizing annual maximum flows by antecedent streamflow and causative precipitation helped identify trends in flooding response. Analysis of contemporary storm events using Next Generation Weather Radar (NEXRAD) stage III precipitation data showed that Georges Creek floods are characterized by higher peak runoff and a shorter centroid lag than Savage River floods, likely attributable to differences in current land use. Interestingly, Georges Creek produces only two thirds of the stormflow volume as Savage River, apparently because of infiltration into abandoned deep mine workings and an associated transbasin diversion constructed circa 1900. Empirical trend analysis is thus complicated by both hydroclimatic variability and the legacy of deep mining in the basin.

Slurry Pipelines: Past, Present and Future

The world’s first long-distance mineral slurry pipeline was built in Australia in 1967for the Savage River magnetite concentrate mine in Tasmania. Since then, in the Australasian region, the following slurry pipelines have been built: the 24 km Gladstone limestone pipeline; the 18 km NZ steel ironsand pipeline; the 304 km Century zinc/lead concentrate pipeline; and most recently the 62 km OneSteel Whyalla magnetite pipeline commissioned in 2007. The current paper reviews the development of long-distance pipeline technology, describes the existing pipelines in the Australian region, and considers the engineering, construction, operation and current status and future of long-distance slurry pipelines in Australia.

A comparison of techniques to sample salamander assemblages along highland streams of Maryland

Amphibians may be useful indicators of biological condition in small streams so determining which sampling technique maximizes encounters at the least cost and at the optimal time of year is important. Area constrained surveys (ACS), used by the Maryland Biological Stream Survey, were tested against cover board surveys, drift fences with pitfall and funnel traps, quadrat leaf litter searches, and leaf litter bags. Sixteen, 100 m-long sites were established in headwater streams in the Savage River State Forest in Garrett County, Maryland. Each technique was randomly assigned to a 25 m stream section within each overall sampling site, and sites were sampled once each month from May to October (2005) with additional sampling in March and April (2006). Area constrained surveys yielded means of 2.7 taxa and 14.9 total individuals per sampling visit, which was significantly higher than the yield of all other methods in all months except October and March, when yields were low for all techniques. Area constrained surveys were also significantly more cost-effective per taxon and per individual compared to all other methods. September produced the most taxa and individuals, October and March produced the least, and yields for April through August were similar to September. We employed removal sampling at four sites in April 2006, but abundance could not be estimated because a significant linear decrease in the accumulated catch versus catch per unit effort did not occur for three of the sites.

English

In 1979, the Maryland Abandoned Mine Inventory (MAMI) estimated that over 450 miles of Maryland streams had been damaged by acid mine drainage (AMD) from abandoned pre-law coal mine sites. Aaron Run, a sub- drainage of the Savage River Watershed, has been severely impacted by acid mine drainage from pre-law mining activities, and is now listed on Maryland's 1998-303 (d) list of Water Quality Limited Segments (WQLSs) for pH impairment. In 2005 the Maryland Department of Environment, Bureau of Mines (MDE-BOM) submitted a proposal, and received funding through the Environmental Protection Agency's (EPA) 319 program to demonstrate de-listing of Aaron Run. Overall, the remediation plan developed and carried out by the MDE-BOM, proposes to mitigate AMD impacts at 3 project locations, to raise the entire stream's average pH from approximately 3.3 to 7.0, and eliminate the majority of all AMD inflow. Treatment technologies will include Aluminator© systems, limestone leach beds and a limestone doser, in 2008. MDE-BOM initiated the formation of the Savage River Watershed Association (SRWA) along with numerous cohesive partnerships. These partnerships have facilitated applying for match funding through OSM Watershed Cooperative Grants, and other sources. The SRWA has provided in-kind services through volunteer effort to help with the monitoring of Aaron Run. The Savage River Watershed Association hired an OSM/VISTA (Office of Surface Mines/Volunteer in Service to America) in June 2007 to assist with monitoring of planned project sites and to build capacity of the organization. The Aaron Run Watershed Restoration initiative is an ideal opportunity to exemplify a holistic approach to watershed restoration through joint efforts. There is potential to de-list a watershed from Maryland's 1998-303(d) list, restore a currently extirpated population of native brook trout, remediate numerous AMD impacts, and protect important economic fisheries resources. Because the Savage River is known for its pristine quality and is frequently used as a reference site to characterize the quality of other streams, it is truly a priority conservation system. Success of the Aaron Run restoration effort may lead the way for future regional watershed restoration efforts.

Relationship Between Wetlands and Mercury in Brook Trout

The purpose of this study was to determine if wetlands influence mercury concentrations in brook trout (Salvelinus fontinalis), benthic macroinvertebrates, and stream water. On September 26, 2005, water samples, benthic macroinvertebrates, and brook trout were collected from four streams in western Maryland under low-flow conditions. Water samples were also collected in these four streams under high-flow conditions in January 2006. The watersheds of Blue Lick and Monroe Run did not contain wetlands, but the watersheds of the Upper Savage River (3% of upstream area) and Little Savage River (7% of upstream area) contained wetlands. We found significantly (p = 0.05) higher average total mercury concentration in brook trout from Little Savage River (129 +/- 54 ng g(-1)); intermediate concentrations (66 +/- 19 ng g(-1)) in brook trout from Upper Savage River; and lowest concentrations in brook trout from Blue Lick (28 +/- 11 ng g(-1)) and Monroe Run (23 +/- 19 ng g(-1)). Brook trout in all streams accumulated mercury at the same rate over their lifetimes, but the youngest fish had significantly different mercury concentrations (Little Savage > Upper Savage > Blue Lick = Monroe Run), which may be due to differences in mercury concentrations in the eggs or food for the fry. Mercury concentrations in brook trout were not consistent with mercury concentrations in stream water and benthic macroinvertebrates. The Little Savage River had significantly higher total and methylmercury concentrations in stream water, but mercury concentrations in the other streams and in the benthic macroinvertebrates were not significantly different among streams. The unusually high methylmercury concentrations (0.5 to 2.1 ng L(-1)) in the Little Savage River may have been caused by production of methylmercury in the pools. The relatively low methylmercury concentrations in the Upper Savage River may be caused by a mercury concentration gradient downstream of the wetland.

English

The Savage River Mine has operated as an open cut iron ore mine on the northwest coast of Tasmania since the mid 1960's. The impact from ARD became evident during the 1990's when monitoring found high levels of Cu and low pH in the river over 30 km downstream of the mine. Closure of the mine in the mid 1990's and subsequent reopening by new owners resulted in funding of approximately A$24M for remediation to be administered by a joint committee representing the mine owners and the Tasmanian state government. Ecotoxicology work showed that Cu was not acutely toxic to aquatic life forms provided alkalinity levels of more than 15mg/L and pH>6.5 were maintained in the river. A feasibility study established methods of achieving these goals by a range of measures including oxygen exclusion covers, water shedding covers, ARD catch drains, pumping systems and use of centralized treatment facilities. The utilization of naturally occuring magnesite and other alkaline rocks was of particular interest. Capital and operating costs of possible options were estimated to +/- 30% for comparison then a whole of site strategic plan developed to demonstrate how the required level of remediation could be achieved and maintained over a 60-year time span using the funds available. The Strategic Plan showed the committee that the aims of remediation were achievable and delivered a program that could be met by staged development making effective use of the operating mine resources. The paper describes the site, the strategic plan and details of the implementation to date.

English

Australian Bulk Minerals purchased the Savage River Mine in 1996 from the Tasmanian government. The mine operates in a wet temperate environment in steep terrain and has an historic environmental legacy of acid rock drainage. Mining personnel have worked with the government to remediate the historic legacy and along the way have developed simple mine planning and mining techniques to maximize the cost effectiveness of the operation. This paper outlines several of those techniques, including ore and waste handling procedures, alkaline flow-through construction, waste dump construction and remediation of an historic acid producing waste dump by construction of combined water shedding and alkaline side covers. ______________________ 1 Paper presented at the 7 th International Conference on Acid Rock Drainage (ICARD), March 26-30, 2006, St. Louis MO. R.I. Barnhisel (ed.) Published by the American Society of Mining and Reclamation (ASMR), 3134 Montavesta Road, Lexington, KY 40502 2 Bruce J. Hutchison is Principal Engineer, Australian Bulk Minerals, Burnie, Tasmania, 7325, Australia, 3 David Brett is Principal Engineer, GHD, Hobart, Tasmania, 7000, Australia 7 th International Conference on Acid Rock Drainage, 2006 pp 810-820 DOI: 10.21000/JASMR06020810

ARTIFICIAL NEST PREDATION ACROSS RIPARIAN-UPLAND FOREST ECOTONES

Abstract On the central Appalachian Plateau, evergreen trees and shrubs often dominate riparian vegetation. In contrast, deciduous trees dominate upland forests. To evaluate an important aspect of habitat suitability for Neotropical migratory birds, we placed artificial nests baited with a Japanese quail (Corturnix coturnix japonica) egg at regular intervals along successively upland transects paralleling Poplar Lick Run and Little Savage River, Garrett County, Maryland. Nests were alternated between 0–0.5 m and 1–2 m heights and were exposed for 12 days during each of four trials in 1990, and 12 days during each of six trials in 1991. Egg predation was typically higher within 50 m of these streams than farther from them. Although artificial nests may not truly represent natural nests and the losses incurred by nesting birds, our results should alert land managers and conservationists to a potential problem and stimulate further research into the suitability of existing, evergreen riparian zones for nesti...

Design and performance of a “flow – through” spillway at Broderick Creek waste rock dump – Savage River mine

Australian Bulk Mineral’s Savage River iron ore mine is located in rugged topography in the NW of Tasmania, a region with rainfall in excess of2000mm per annum. Over its 30 years of operation to date, around 260 million m3 of waste rock has been generated and current mining plans allow potential for a further 160 million m3 over the next 20 years. Disposal of this material poses significant difficulties, not least of which is the practical placement of such large volumes of material.Erosion of early dumps placed in Broderick Creek was recognised as an environmental issue and led to a review of spillway options for the dump, which was effectively damming the valley. Lying parallel to and to the west of the northern deposits of the mine, Broderick Creek was a logical waste rock disposal site if stormwater flow could be properly managed. The review led to adoption of an innovative flow-through spillway, which utilised hard coarse waste rock as a drainage zone. Construction was successful and has led to extension of this concept for further major development of waste dumps at the site.Design of flow-through spillways in Tasmania was first looked at by the eminent Hydro Electric Commission engineer, the late John Wilkins. Wilkins used the concept successfully at Laughing Jack Dam and later at the North Slot Dam at Savage River.The paper describes the work of Wilkins and how this was used to design the Broderick Creek structure. Results of site flow monitoring are used to demonstrate the effectiveness of the design and actual permeability values achieved.