Montana Tech Research Articles

Chevron Applies Some Unconventional Thinking To Try To Make Shale EOR a Standard Treatment

In the shale business, the closest thing now to enhanced oil recovery (EOR) is improved techniques. During an earnings call last November an analyst asked EOG Resources executives about their enhanced completion technique which EOG reported was adding 20% to first-year well production in the Permian. Improved completions have allowed operators to significantly increase early production year after year, but after that, steep declines are a given. Back in 2016, EOG was talking about how it was increasing oil production significantly by injecting millions of cubic feet of gas a day into wells in the Eagle Ford. It triggered an EOR field-testing boom by competitors hoping to match reported reserve increases of “30 to 70%.” In a 2017 JPT story, Deepak Devegowda, a petroleum engineering professor at the University of Oklahoma, said, “This is the name of the game. Everybody is talking about EOR and pumping money into trials of EOR.” Now the only mention of the acronym EOR on EOG’s website is an item in its corporate history timeline for 2016: “We commercialized the first enhanced oil recovery process, or EOR, in shale.” In recent years, reported shale EOR work has been mostly in the form of occasional papers describing production uplift by companies selling ways to increase production by injecting gas or chemicals. EOR effectiveness isn’t the issue, according to Todd Hoffman, a petroleum engineering professor at Montana Tech University who wrote two papers evaluating EOG’s methods cited in two Chevron papers. “The EOG field work showed us that these projects can produce significant additional oil and be economically positive,” he said. The problem is that drilling and fracturing wells delivers “higher economic returns than the EOG-style EOR projects with the huge compressors, high gas rates, and high injection pressures.” Last year in the middle of this EOR drought, Chevron did something different. It delivered two papers revealing a major company-scale effort to find ways to use chemical and gas injections to economically produce more oil. The papers presented at the 2023 Unconventional Resources Technology Conference (URTeC) reported on field tests of surfactants and natural gas injection on Permian Basin wells which delivered sufficiently encouraging results to justify an expanded testing program. (URTeC 3870505 and URTeC 3871386). Chevron described a systematic effort by its corporate technical unit and its Mid-Continent business unit to rethink shale EOR methods based on the unconventional nature of flow through fractured reservoirs and the economic realities in a business where new EOR technology is competing with the profitable status quo. Its methods challenge accepted notions about the role of EOR. In SPE’s disciplines, EOR normally falls under the production topic, “marginal aging fields.” What Chevron tested is better described by the topic, “well interventions.” Rather than looking at these techniques as a way to eke out the last barrels from old wells, the papers describe methods that can be deployed earlier in the life of these short-lived wells.

Using Laboratory Results from New Methods of Measuring Proppant Conductivity to Model Hydraulic Fractures in Reservoir Simulation

Purpose: Hydraulic fracturing processes are conducted to create new fractures in a rock to increase the size, extent, and connectivity of existing fractures. The American Petroleum Institute (API) developed two testing procedures for measuring conductivity of proppants in a laboratory setting, namely; the Short-Term Proppant Conductivity Testing Procedure and Long-Term Proppant Conductivity Testing Method. However, these laboratory testing methods have produced inconsistent results, with a significant coefficient of variance of ±80% from one test to the other even with the use of the same proppants and procedures. Thus, this work seeks to use an improved laboratory variance from Montana Tech conductivity measurements to model hydraulic fractures in reservoir simulation to evaluate how it performs or compares with field performance.
 Methodology: Montana Tech researchers have developed new proppant conductivity testing methods to lower this variance. These testing procedures showed more consistent results with an average variance of ±7.6% and ±14.3% in ceramic and sand proppants respectively. These tests were all done at laboratory conditions and therefore this work used field production data obtained from the Willison Bakken Formation and an arbitrary high permeability value as a benchmark against the fracture models built using laboratory results from the new methods of measuring proppant conductivity testing by Montana Technological University.
 Findings: The conductivity values corresponding with 6,500 psi closure stress obtained for sand and ceramic were 2,133.5 md-ft and 4,870.3 md-ft respectively. The high permeability model recorded an incremental recovery increase of 42% over the unfractured model. Similarly, the laboratory sand and ceramic models had an incremental recovery increase of 12.9% and 33% respectively over the unfractured model. The dimensionless fracture conductivity for the laboratory sand, laboratory ceramic and high permeability models were 1,246, 2,844 and 233,577 respectively. Generally, laboratory conductivity overestimates field performance, however, this work did not show an improvement in modeling fractures using laboratory data as a result of the extremely low porosity and permeability values of the Bakken wells used for the study and the limitedness of the software package used. Simulation of low permeability reservoirs is still an area in development as traditional models often fail to produce results that match the physics. It is possible that as simulation methods for these types of reservoirs improve, the new laboratory data for fracture conductivity will prove beneficial in modeling.
 Unique contribution to theory, practice and policy (recommendation): A sensitivity analysis should be performed in Petrel that starts with the laboratory fracture conductivity and ends with infinite fracture conductivity. This would help determine the effect of correctly measuring fracture conductivity. Again, a better technique in Petrel such as using a tartan grid is encouraged to better assess the performance of each of the fractures and lastly, more well data with associated measured porosity and permeability data is suggested for future works.

Developing Trees Tolerant to Degraded Mine Soils in an Underground Greenhouse

This project is exploring the potential for developing trees tolerable to degraded un-reclaimed mine site soils and tailings as a solution to re-establishing long-term tree growth on those sites. The project incorporates growing tree seedlings in an underground greenhouse grown from seeds planted in the degraded mine soils in which they will eventually be planted. The outcome of the project is expected to lead to a successful solution for re-establishing tree growth in soils and tailings containing high metal concentrations with minimal post-planting human intervention. The research is being conducted in an underground greenhouse located 100 ft below the surface in the old Orphan Boy Mine Underground Mine Education Center (UMEC) located on Montana Tech’s campus in Butte, Montana.

Huff 'n' Puff Gas-Injection Pilot Improves Oil Recovery in the Eagle Ford

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 189816, “Huff ’n’ Puff Gas-Injection Pilot Projects in the Eagle Ford,” by B. Todd Hoffman, SPE, Montana Tech, prepared for the 2018 SPE Canada Unconventional Resources Conference, Calgary, 13–14 March. The paper has not been peer reviewed. The Eagle Ford formation has produced approximately 2 billion bbl of oil during the last 7 years, yet its potential may be even greater. Using improved oil-recovery (IOR) methods could result in billions of additional barrels of production. While a number of companies have field-tested an IOR method called huff ’n’ puff gas injection, most of the published results are from laboratory and modeling studies. This paper evaluates the results of these field tests and discusses the potential of the huff ’n’ puff method in the formation. Introduction The Eagle Ford formation, formed during the late Cretaceous, is a laminated calcareous organic rich shale. The shale was deposited in a low-energy anoxic marine shelf environment, which allowed for rapid deposition and burial of abundant organic material. The Eagle Ford is divided typically into two sections: the Upper, which was deposited during a regional marine regression, and the Lower, which was deposited during a transgressional period and tends to have more organic-rich black shale. The Eagle Ford is laterally continuous and spatially extensive throughout much of southern Texas. The matrix permeability of the reservoir is low enough that typical hydrocarbon migration is restricted, causing the oil-rich rocks to be stratigraphically higher than the gas-filled ones. Results of Previous Huff ’n’ Puff Pilot Projects The huff ’n’ puff process involves injecting a miscible gas into a well and then, after some time has passed, producing back from that same well. Data have been collected on seven pilot projects in the Eagle Ford that have been completed during the last 5 years. Data from four of these seven are discussed in this synopsis. All of the pilots used hydrocarbon gas, but the composition of the gas varied across the locations. In addition, all of the field trials used a huff ’n’ puff injection scheme. Pilot A. The first pilot was a single isolated well where the nearest offset producers were more than 2 miles away. This provided some assurance that the injected gas would not migrate to other wells. The oil rates for the well indicated a positive response to the process. Each cycle increased the production rate to approximately half of the well’s initial rate. Once the oil rate began to drop, another injection cycle was started. This is encouraging because not only the first cycle but also subsequent cycles were able to increase production.

W. Franklin Gilmore

W. Franklin Gilmore, 82, died on Feb. 14 in Oxford, Miss. “Frank Gilmore devoted his professional life to academia and the advancement of chemistry. He was a professor at the School of Pharmacy at the University of Mississippi for 26 years before becoming provost at West Virginia University Institute of Technology and then chancellor at Montana Tech. He also served as president of the Goldwater Scholarship Foundation and of Sigma Xi and as a reviewer for the National Association of Boards of Pharmacy licensure exam for 34 years. His research included the development of peptidomimetics, the first synthesis of optically active amino phosphonic acids, and the first synthesis and biological evaluation of peptides containing amino phosphonic acids.”—Ann Gilmore, wife Most recent title: President, Goldwater Scholarship Foundation Education: B.S., chemistry, Virginia Military Institute, 1957; Ph.D., organic chemistry, Massachusetts Institute of Technology, 1961 Survivors: Wife, Ann; daughter, Kristin Newman; son, Paul To

Engineering Tourism: Sightseeing across the Curriculum for Non-STEM Librarians

Advice for librarians' professional development sometimes includes encouragement to attend classes, but the benefits for STEM librarians have not been well defined. This article describes a study in which engineering librarians at the University of Vermont and Montana Tech of the University of Montana observed class sessions across first-year engineering programs. The study provided numerous insights into the orientational design of these programs, the scope of the curriculum, building relationships with different groups, the importance of relating instruction to professional success, opportunities for integrating library services, and the ability of non-expert librarians to support STEM programs. This article also provides suggested best practices for an observational project of this kind.

High Precision Characterization of Lithium Plating and Abuse Response during Extreme Fast Charge (XFC) of Lithium Ion Batteries

Increasing EV pack size and customer expectations are necessitating the push towards higher charger rates, culminating in what the Department of Energy Vehicle Technology Office deems “Extreme Fast Charge” (XFC), which is charging to 80% of the battery capacity in 10 minutes. Though charge rates have generally increased over the last 10 years, cell development has kept pace because moderate charge rates have not introduced new degradation mechanisms. However, with XFC rates approaching 4C, lithium plating has been commonly observed.[1] Sandia National Labs is uniquely qualified to characterize this phenomenon, particularly from the perspectives of early detection and impact on abuse response / safety. This talk will describe Sandia’s work to better characterize lithium plating over several variables, including cell chemistry, charge rate, and temperature. High precision cycling, a result of partnership with Arbin, Ford Motor Company, and Montana Tech, will be used to accurately measure cell efficiency and identify markers of lithium plating.[2] While similar approaches have been reported in the past,[3] Sandia’s high precision tester offers extreme levels of Measurement Precision (25ppm), Timing Precision (5ppm), and control accuracy (< 0.003%) to derive earlier and more accurate Li plating evidence. [4] We will also report results a Rapid EIS technique, which completes scans in under 10 seconds, to identify impedance-related markers for lithium plating. The technique allows fast EIS scans during applied fast-charge loads, providing a window into electrode interface events as they occur. In additional to early detection of lithium plating, Sandia is uniquely qualified to assess the safety impacts of XFC and potential lithium plating. Abuse response of cells will be characterized after varying degrees of fast charge, including initiation points of thermal runaway and changes in EUCAR ratings. Lithium plating will be quantified, and any unique safety implications of molten lithium during safety events will be discussed, especially any increases in thermal runway sensitivity. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy?s National Nuclear Security Administration under contract DE-NA0003525. [1] S. Ahmed et al., J. Power Sources, 367, p. 250 (2017). [2] A. Masias, "Electrochemical Prozac: Relieving Battery Anxiety through Life and Safety Research,” in Frontiers of Engineering: Reports on Leading-Edge Engineering from the 2014 Symposium, p. 25, The National Academies Press, Washington, DC (2015). [3] A. J. Smith, J. C. Burns, S. Trussler, J. R. Dahn, J. Electrochem. Soc., 157 (2), A196 (2010). [4] Arbin Instruments HP Tester Specifications, http://www.arbin.com/products/coulombic-efficiency/ (2016).

EOR-For-Shale Ideas to Boost Output Gain Traction

Low oil prices may not be the biggest threat to the long-term sustainability of the North American shale business. Some are more concerned about the low recovery rates of horizontal shale wells, estimated to be about 7% on average— far short of the 40% achieved through primary and secondary (waterflooding) production in conventional reservoirs. Refracturing has been touted as the next big thing to improve ultimate recovery, but such operations remain relatively expensive and may only temporarily reset production to initial rates once or twice in a well’s life. To see long-term results and a doubling or tripling of current recovery rates, a number of experts say enhanced oil recovery (EOR) technologies must be developed to work in tight shale reservoirs. And due to persistently low natural gas prices, current efforts appear to be exclusively focused on oil and condensate producing wells. It is early days for this area of EOR research. There is no consensus on which approaches will work best, how much they may cost, what the most pressing challenges are, or exactly when an EOR operation should begin. “Our understanding is really small,” said Todd Hoffman, an assistant professor of petroleum engineering at Montana Tech University. “We’re coming from the conventional world where ‘this’ is how we did EOR and we may just have to throw all that out.” Hoffman is one of several researchers trying to figure out how EOR methodologies can be adapted or reinvented for the oil-rich shale fields of North Dakota, Texas, and Canada. One of the most popular ideas being studied is a huff-and-puff approach that uses a single horizontal well to alternate between producing oil and injecting natural gas or CO2 to re-pressurize the reservoir and displace oil. Another idea is to apply continuous injections into one well and use an offset well as the producer. Others are looking into flooding the wells with surfactants and possibly acid to stimulate production. In May, EOG Resources laid claim to the first economic demonstration of an injection-based EOR technology for tight oil in the US. The company said the development may have long-term production benefits and is competitive with drilling new wells. But other than making it clear that the process has been successful and uses dry gas produced in the same field, EOG is withholding key operational details such as whether it involves the huff-and-puff technique or continuous injections. A number of other innovative shale producers including Statoil, Nexen Energy, Continental Resources, and Marathon Oil have also either funded research or are known to be running pilots, but have not made their results public. As most shale producers remain silent about their EOR efforts, there are a growing number of technical papers being published by university petroleum departments and reservoir engineering consultants. They are using computer models and corefloods to test their theories and have produced promising numbers that suggest there may be several practical ways to implement EOR strategies for shale.

Carbon Dioxide May Offer An Unconventional EOR Option

As the daily oil output of the Bakken and Eagle Ford formations rose toward 1 million B/D, researchers were seeking a way to push the ultimate recoveries in these formations, where producing 6% of the oil in the ground is now considered good. One line of attack on the problem is using carbon dioxide (CO2) to get more oil from tight formations where rapid production declines are the norm. In laboratories at the Energy and Environmental Research Center (EERC) at the University of North Dakota and at Texas A&amp;M University, experiments have shown that carbon dioxide circulated around a small sample of source rock can remove a significant amount of oil. Now, the scientists are trying to understand how it works and if those lab results can be applied in the real world. “It is incredible what CO2 can do,” said John Harju, associate director for research at the EERC, while describing the center’s research program at the annual CO2 Flooding Conference in Midland, Texas. “The really big prize is (overcoming) the innately low recovery rate in these shale plays,” said David Schechter, an associate professor of petroleum engineering at Texas A&amp;M University who is turning his expertise in conventional enhanced oil recovery to unconventional reservoirs. While laboratory results normally show much higher recovery than field results, even a 1% improvement of recoveries in the Bakken formation could yield more than 1 billion bbl of oil, according to an EERC paper. Previous SPE papers, based on reservoir simulation work at Montana Tech of the University of Montana and the Colorado School of Mines, concluded that significant increases in ultimate oil recovery might be possible using CO2 injections. One of the biggest backers of the work in North Dakota has been Harold Hamm, the chief executive officer at Continental Resources, which pioneered unconventional liquids development and is the biggest acreage holder in the Bakken, Harju said. On the basis of early tests using CO2 and similar positive results from using chemical surfactants, Texas A&amp;M is working to recruit support from oil companies for a joint industry project called the Enhanced Oil Recovery in Unconventional Reservoirs Joint Industry Project. Both the EERC and Texas A&amp;M have tested samples ranging in size from Chiclets—square bits of reservoir rock about the size of the popular chewing gum—to small core samples about the size of a disposable lighter. The tests produced significant amounts of oil from samples exposed to CO2 flowing through a test chamber simulating reservoir conditions.

After Freedom Summer: how race realigned Mississippi politics, 1965-1986

A brilliant history of black politics and white resistance in post civil rights era Mississippi. Danielson s work helps to fill the yawning gap in the black politics historiography between the Black Power movement and contemporary black politics. Additionally he makes a critical contribution to the literature of the racial realignment of the two major political parties. A must-read! G. Derek Musgrove, University of the District of Columbia A sobering account of what happened after the singing and marching stopped. Danielson s masterful analysis of Mississippi s racially divided electorate proves that, despite the election of hundreds of blacks to public office, whites still hold all the levels of political power. John Dittmer, author of Local People: The Struggle for Civil Rights in MississippiNo one disagrees that 1964 Freedom Summer forever changed the political landscape of Mississippi. How those changes played out is the subject of Chris Danielson s fascinating new book, After Freedom Summer. Prior to the Voting Rights Act of 1965, black voter participation in Mississippi was practically zero.Aftertwenty years, black candidates had made a number of electoral gains. Simultaneously, white resistance had manifested itself in growing Republican dominance of the state. ?Danielson demonstrates how race not class or economics was the dominant factor in white Mississippi voters partisan realignment, even as he reveals why class and economics played a role in the tensions between the national NAACP and the local Mississippi Freedom Democratic Party (an offshoot of SNCC) that limited black electoral gains.Using an impressive array of newspaper articles, legal cases, interviews, and personal papers, Danielson s work helps fill a growing lacuna in the study of post civil rights politics in the South.Chris Danielson is assistant professor of history at Montana Tech University.

Neural Network and Support Vector Machine Classification of UXO Using Magnetics Finite Element Modeling Data

A recently completed Montana Tech study used finite element modeling to calculate magnetic dipole moments for realistic unexploded ordnance (UXO) shapes found at Montana Army National Guard training sites. The modeling approach compared predictions from a simple prolate spheroid model, typical for conventional modeling, with a complex shape constructed using computer aided design (CAD). The complex shapes embody all of the features of the actual UXO bodies. Results showed that the larger, more accurate dipole moments calculated from the complex shape can be used to adjust the dipole moment discrimination level, ultimately reducing the number of targets to be dug.

A preliminary investigation into the effect of pressure on flotation performance

In a previous study, various pyrite depressants were examined to improve the flotation performance of a copper-sulfide ore containing tetrahedrite (Cu12Sb4S13). Optimal results from this study were used to examine the effect of elevation on recovery and grade. Tests were conducted at elevations of 3,350 meters, 1,735 meters, 610 meters, and-760 meters, consisting of five repetitive experiments for statistical analysis. The experiments were performed both with and without airflow control. Tests were also performed in a glove box at Montana Tech of The University of Montana to mimic the pressure conditions. Results indicate that both recovery and grade are dependent on pressure via bubble size and airflow, suggesting that pressurized fl otation cells should be considered for operations, particularly those at high elevation. Economics are extremely favorable for implementation because ensuing capital expenses are inconsequential with minimal time for return-on-investment.

Superfund Site Harbors Extremophiles Producing Potent Compounds

About 200 miles from Yellowstone National Park, is a site not as scenic, yet proving nearly as exotic in terms of its rich diversity of extremophiles. Instead of geysers and hot springs, the Berkeley Pit in Butte, Mont., contains 30 billion gallons of highly acidic waters (pH 2.5) from abandoned copper mines. The Berkely Pit is the largest site in the Environmental Protection Agency’s Superfund program, which provides money for environmental cleanup at hazardous waste sites. Although nearly saturated with sulfates of iron, copper, aluminum, and zinc, the seemingly inhospitable waters and sediments in the Berkeley Pit yield more than 60 different microorganisms, including some that produce compounds that kill cancer cells and are active against other drug discovery targets, according to Andrea and Donald Stierle at Montana Tech of the University of Montana in Butte and their collaborators.

Land Streamer Aided Geophysical Studies at Saqqara, Egypt

During December 2002 and January 2003, Montana Tech in collaboration with Ain Shams University, Cairo, collected Ground Penetrating Radar (GPR) and seismic data at Saqqara, Egypt. The purpose of this study was to see if GPR and seismic methods could detect manmade structures in the subsurface at Saqqara. In particular, land streamer aided, seismic diving-wave tomography was tested as a method to detect archaeological features. Saqqara was one of the principal necropolises of Memphis, an ancient capital of Egypt. The research site was near the 3rd Dynasty pharaoh Djoser’s Step Pyramid—the first monumental structure built entirely of stone. A preliminary GPR study of our site yielded numerous, possibly manmade features in the subsurface with a [Formula: see text] depth of penetration using [Formula: see text] antennas. A follow-up three-dimensional (3-D) GPR survey over one of the more interesting features showed a broad trench underneath the flat-lying sand that is seen at the surface. This feature is most likely manmade because the horizontally layered limestone rocks of Saqqara are inconsistent with the shape of this feature. Seismic diving-wave tomograms show that this probable manmade feature extends to a depth of [Formula: see text] into the subsurface. Moreover, we were able to complete the seismic survey faster using a land streamer consisting of gimbaled geophones than could be done using conventional planted geophones. This site has potential for further investigation and possible excavation.

English

For the past 13 years, the Mine Waste Technology Program (MWTP) has been operated by MSE with administrative assistance from the Department of Energy (DOE)'s Western Environmental Technology Office (WETO) and technical direction from EPA's National Risk Management Research Laboratory (EPA-NRMRL). A portion of the MWTP funding has been used to perform Field Demonstrations of innovative technologies with the potential to address mine waste issues. This paper will highlight current and past MWTP successes and discuss important lessons learned. Over 70 distinct projects have been completed or are currently being performed by MSE and Montana Tech of the University of Montana. Some issues addressed by these projects include: sustainability; acid drainage/water treatment; trace/heavy metal removal; remote locations; source control; pit lakes; and heap detoxification/closure. Other projects are focused on prediction, characterization, and modeling. Within the past year, new MWTP management personnel have been assigned at MSE, EPA-NRMRL, and Montana Tech of the University of Montana providing an opportunity for positive evolution of the MWTP. Future strategies for MWTP success will also be presented.

Sulfide detection in drill core from the Stillwater Complex using visible/near‐infrared imaging spectroscopy

This feasibility study examines the potential of imaging spectroscopy to estimate sulfide percentage in drill core from the Stillwater Complex, Montana. The Stillwater Complex is a layered mafic to ultramafic intrusion hosting ore‐grade platinum group elements within the zone known as the JM Reef. Stillwater Mine geologists indirectly infer the platinum/palladium grade by the presence and abundance of sulfide minerals. In order to discriminate between waste and ore rock, geologists visually inspect the core and working faces for minerals such as chalcopyrite, pentlandite, and pyrrhotite. Iron sulfide minerals have a strong ultraviolet absorption that blends into the blue portion of the visible region and produces their yellow luster. The spectral differences between these pathfinder minerals and the accessory minerals are sufficiently distinct to allow classification of this mineralogy using imaging spectroscopy even in the absence of a particular absorption feature. Five different sections of split core from the JM Reef were chosen for their representative mineralogical character. The surface of each sample was scanned with Montana Tech's prototype Airborne and Laboratory Imaging Spectrometer (ALIS) and the images were analyzed for sulfides. For validation, the amount of sulfides was independently determined visually with counting grids. The imaging spectrometer results correlate well with the point‐count percentage, although all five samples consistently fall below the point‐count average. This underestimation is possibly due to metal ion substitution, linear mixing at mineral boundaries, or anisotropic scattering due to the high spatial resolution of the spectrometer. The success of this experiment suggests possible machine vision applications in future mining operations, such as automation of core logging and downhole instrumentation.

Strength and Conditioning for Reality Fighting

Montana Tech University of Montana Butte, Montana West Side Judo & Vale Tudo Club Butte, Montana John Amtmann is a professor of Applied Health Sciences at Montana Tech of the University of Montana in Butte, Montana. Steve Berry is a strength and conditioning coach at the West Side Judo & Vale Tudo Club in Butte, Montana.

Strength Training In Prisons

Applied Health Science Montana Tech of The University of Montana John Amtmann is a professor of Applied Health Sciences at Montana Tech of the University of Montana in Butte, Montana.

Strength and Conditioning for Reality Fighting

Montana Tech University of Montana Butte, Montana West Side Judo & Vale Tudo Club Butte, Montana John Amtmann is a professor of Applied Health Sciences at Montana Tech of the University of Montana in Butte, Montana. Steve Berry is a strength and conditioning coach at the West Side Judo & Vale Tudo Club in Butte, Montana.

BACTERIAL EFFECTS AND ALGAL BIOREMEDIATION BY CHLORELLA ELLIPSOIDEA GERNECK OF THE BERKELEY PIT LAKE SYSTEM

Mitman, G. G.Department of Biological Sciences, Montana Tech of The University of Montana, Butte, MT 59701The Berkeley Pit Lake System is one of the largest contaminated sites in North America and is located near the headwaters of the largest superfund site in the U.S. It is filling at a rate of about 28.7 million liters per day with metal laden, acidic (pH 2.7) water. Chlorella ellipsoidea is one of the first autochthonous species of algae from the Berkeley Pit Lake System to be tested for its bioremediative potential. An experimental matrix was designed for this experiment using a completely randomized design (CRD). The matrix was set up with tissue culture flasks having the following treatments: Na2HPO4 at 0, 25, 50, 75, 100 mg/l, inoculated vs. no‐ inoculated with algae (187,500 algae/ml final), and filtered (0.2Fm) vs. non filtered pit water as variables, NaNO3 amount was fixed at 53 mg/ml. Three replicates were made of each and the experiment lasted 60 days. The results of this experiment demonstrated significant remediation of most metals. These results will be presented. In addition, filtering seemed to negatively impact the bioremediative potential of the cultures. As a result, axenic cultures of Chlorella ellipsoidea will be tested in Berkeley pit water to determine if it is bacteria or filtration that caused these results.