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Presentations Acid Drainage Technologies for Metal and Coal Mining Meteoric Water Mobility Procedure (MWMP) Standardization Through the ASTM Consensus Process: C. Bucknam, Newmont Metallurgical Services, Englewood, CO; G. McClelland, McClelland Laboratories, Inc., Sparks, NY; and S. Wilson, US Geological Survey, Denver, CO MWMP was developed in the state of Nevada during the 1980's as part of the mine waste characterization programs. During the 1990's the Waste Subcommittee of the Nevada Mining Association (NMA) contacted ASTM Subcommittee E01.02 on Ores, Concentrates and Metallurgical Materials to undertake a standardization program for the method. A cooperative program was developed in conjunction with the Acid Drainage Technology Metal Mining Sector Prediction Committee, which involved eight of the NMA labs performing duplicate leaching tests on two test materials: a coarse fraction of the USGS Hardrock Mine Waste Standard and a typical spoils sample from a heap leach operation in Nevada. Solutions for metals analysis were preserved and sent to the USGS Lab in Denver to determine the reproducibility and repeatability of the leaching. The history of the method, reference material and resu!ts of the testing will be presented. Presentation Acid-Base Accounting to Predict Post-Mining Drainage Quality on Surface Mines: Acid-Base Accounting (ABA) is an analytical procedure that provides values to help assess the acid-producing and acid-neutralizing potential of overburden rocks prior to coal mining and other large-scale excavations. This procedure was developed by West Virginia Univ. scientists during the l960's. After the passage of laws requiring an assessment of surface mining on water quality, ABA became a preferred method to predict post-mining water quality, and permitting decisions for surface mines are largely based on the values determined by ABA. In order to predict the post-mining water quality, the amount of acid-producing rock is compared to the amount of acid-neutralizing rock, and a prediction of the water quality at the site (whether acid or alkaline) is obtained. Geologic and geographic data for 56 mined sites in West Virginia were gathered. Presentation Solid Phase Characterization for Metal Mine Waste Drainage Quality Prediction: Static tests estimate the capacity of mine waste to produce and neutralize acid and are used as tools for predicting metal-mine waste drainage quality. Various methods and resulting accuracies are addressed. More accurate quantification of thee capaciteis, as well as availability and reactivity, may be necessary to predict drainage quality from some mine wastes. Chemical analyses, x-ray diffraction, optical microscopy, scanning electron microscopy, and electron beam analyses are among the techniques commercially available to more accurately quantify these capacities and provide insight into availability and reactivity. Development of the ADTI-WPl (Humidity Cell) and ADTI-WP2 (Leaching Column) Standard Weathering Procedures for Coal Mine Drainage Prediction: R Hornberger, Pennsylvania Dept. of Environmental Protection, Pottsville, PA; K. Brady, Pennsylvania Dept. of Environmental Protection, Harrisburg, P A; J. Cuddeback, Dyncorp Environmental, Alexandria, VA; W. Telliard, US Environmental Protection Agency, Two weathering procedures are being developed by the Acid Drainage Technology Initiative in cooperation with federal agencies (05M and EP A). Objectives are to 1) standardize existing humidity cell and leaching column procedures; 2) improve test methods by maintaining a carbon dioxide enriched environment needed to optimize carbonate mineral dissolution, and quantifying particle size variables to evaluate reaction kinetics, and 3) provide flexibility in test method implementation consistent with EPA guidelines for Performance-Based Measurement Systems. Preliminary results indicate the CO2-enriched leaching environments produce alkalinities that are similar to field observations and greater than the tests run under atmospheric PCO2' Leaching columns produce higher alkalinity than humidity cells. Effect of Salinity on Generation of Acid Rock Drainage at a Former Industrial Site: N. Nijhawan, Royal School of Mines, London, England A site on the shores of the San Francisco Bay is contaminated by pyrite cinders generated during the manufacture of sulfuric acid; these cinders are releasing acid and metals to an adjacent marsh and the Bay. The wastes are subject to tidal influence. In order to assess the effect of salinity on the rate at which acid is released from pyrite, cinder cores were exposed to cyclical saturation by solutions with different salinity, followed by drainage. Results on the rate of acid release directly influenced the eventual remediation strategy to be used at the affected site. Long-Term Performance of Passive Acid Mine Drainage Treatment Systems: P. Ziemkiewicz, J. Skousen, and J. Simmons, West Virginia Univ., Morgantown, WV Passive acid mille drainage (AMD) treatment systems were developed over the past 20 years to provide reliable, low cost, low maintenance treatment of mille drainage in remote locations. Passive treatment methods can be grouped into about nine cate- gories; this project evaluated the performance of these methods by studying 137 treatment units in eight eastern states. Performance was normalized according to construction cost, projected service life and tons of acid load treated and dimensioned as $/tons of acid load treated/year. These costs were then compared to those of chemical treatment. Sites that achieved acid load reductions at costs below those of chemical treatment were considered successful. In addition to evaluating the performance of the treatment methods, this paper describes the various passive treatment systems, applications and performance data for individual treatment units. The results indicated a high success rate for several passive treatment methods while others had high failure rates. New Mexico Mines Database: V. McLemore, C. Krueger, P. Johnson, J. Raugust, G. Jones, G. Holfman, and M. Wilks, New Mexico Bureau of Geology and Mineral Resources, Socorro, NM The NMBGMR has collected data on mining districts, mines, mills, geochemistry (water, solids), and historic photographs since it was created in 1927 and is slowly converting historical data into a relational database using Microsoft Access 97. The purpose of the database is to provide data on districts, mines, and mills in New Mexico to government agencies, public organizations, industry, and citizens to make informed decisions about resource development/management, water supplies, environmental impacts, hazard assessment, and waste disposal. Once the data are entered into the database with locations, it can easily be converted to GIS format for displaying as different map layers. Preliminary Results of a NASA-Funded Hyperspectral Remote Sensing Project on Natural and Anthropogenic Sources of Impacted Drainage: D.Peters, Peters Geosciences, Golden, CO; P. Hauff, Spectral International, Inc., Arvada, CO; M. Sares, Colorado Geological Survey, Denver, CO; F. Henderson III, HENDCO Services, Nathrop, CO; D. Bird, Colorado Geological Survey, Denver, CO; and E. Prosh and W. Peppin, Spectral International, Inc., Arvada, CO A NASA-funded project is underway to determine the ability of hyperspectral remote sensing to map mineralogy that affects water quality within a watershed and to identify the relative contributions of natural and anthropogenic sources to that drainage. Hyperspectral data allow identification of fine detai1s of mineralogical variations throughout a watershed and, thereby, should improve environmental assessments and tracking of impacts of acidic and/ or metal1iferous drainages. The first part of this project involves the Lake Creek watershed in central Colorado, a large tributary to the upper Arkansas River. The remainder of the project involves the upper Arkansas River and comparison of Lake Creek to the river, where the river is impacted by drainage from the Leadville Mining district and surroundings. This presentation will cover preliminary results of the project derived from the study of Lake Creek. Acid Drainage Technology Initiative, Coal Mining Sector Stephen Parsons, Fred Block, and John Craynon, Office of Surface Mining, Washington, DC; Roger Hornberger, |
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