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An Evaluation of Flue Gas Desulfurization Gypsum For AN EVALUATION OF FLUE GAS DESULFURIZATION GYPSUM FOR ABANDONED MINE LAND RECLAMATION THESIS Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in the Graduate School of The Ohio State University By Rachael A. Pasini, B.A Civil Engineering Graduate Program The Ohio State University 2009 Thesis Committee: Professor Harold Walker, Advisor Professor Linda Weavers Dr. Tarunjit Butalia ABSTRACT The goal of this study is to understand the environmental impacts associated with using FGD gypsum for abandoned mine land reclamation (AMLR) in Ohio. There are over 200,000 acres of abandoned strip mines and over 600,000 acres of abandoned underground mines throughout Ohio that cause physical and chemical hazards to surrounding waterways, soil systems, and wildlife. Ten abandoned mine lands (AMLs) in eastern Ohio were reviewed in order to classify the different types of AMLs and build model scenarios. FGD gypsum samples from two different coal combustion power plants were tested in order to characterize the leaching behavior of the material under a variety of conditions. The USEPA Methods 1311 (TCLP) and 1312 (SPLP) were used alongside a three-tiered framework developed by Kosson et al. In order to assess the overall impacts of using FGD gypsum for AMLR, a Life Cycle Assessment (LCA) was conducted to calculate output emissions and energy consumption. A combination of conventional, ecological, and economic input-output LCA were used in this study. The TCLP and SPLP results yielded concentrations of regulated constituents well below Ohio standards for beneficial use application. Thus, according to such standards the FGD gypsum samples can be classified as nonhazardous substances that present no significant impact on groundwater or risk to public health. The results from the three- ii tiered Kosson et al. framework provided evidence that the leaching of Ca, S, and SO4 is not necessarily affected by pH, but is mainly dependent on the solubility of gypsum. Some constituents, such as Mg and Mn, were dependent upon pH while other showed trends as a function of time. For instance, a majority of the available B was extracted in each experiment and concentration increased over 8 days, but did not change in response to varying pH. Less than 0.02% of Hg was available for leaching in each experiment and decreased over time, suggesting that long-term leaching of Hg is potentially not a concern. Overall, the leaching results demonstrate that the FGD gypsum samples do not present significant impacts on surrounding waters. The LCA results showed that using FGD gypsum for AMLR is a better option than landfilling in terms of overall negative environmental impacts. In addition, it showed that there are only slight differences between reclaiming abandoned highwalls, highwall pits, and underground mine entranceways; though, due to high unit costs gob pile reclamation was shown to be the least favorable option. The results from this analysis do not include the positive impacts associated with reclamation, however, such as acid mine drainage abatement and reduced sedimentation runoff. Thus, stakeholders must weight the trade-offs between cost, benefits of reclamation, and overall negative impacts when developing AMLR plans. iii ACKNOWLEDGEMENTS First and foremost, I would like to thank my parents for always supporting my goals and encouraging my education. Next, I thank Dr. Harold Walker for providing the opportunity to study environmental engineering and gain valuable research and field experience. Thank you to my committee members, Dr. Tarunjit Butalia and Dr. Linda Weavers, for supporting my research. I would like to thank members of the environmental engineering lab group, especially Ruiyang Xiao, Yuan Gao, Mengling Li, Xuan Li, and Qing Le for their friendship and sharing their knowledge in the laboratory. I thank the process system engineering group, especially Bob Urban and Dr. Bhavik Bakshi, for assisting me and inviting me to learn about their research. Thank you to Dr. John Lenhart, Dr. William Wolfe, Robert Baker (Baker Consultants), Richard Warden (ODNR), and Bill Richardson (AEP) for providing instruction and information for my research. To Kevin Jewell at OARDC for performing many laboratory tests and answering my many questions. Last, but not least, I thank my close friends and companions, especially Alex Morison, that make me laugh and encourage me to grow. iv VITA March 1984……………………………… Born June 2002………………………………… Magnificat High School June 2007………………………………… B.S. Industrial and Systems Engineering, The Ohio State University June 2008 to present……………………… Graduate Research Associate, Department of Civil and Environmental Engineering and Geodetic Sciences, The Ohio State University Field of Study Major Field: Civil Engineering Environmental Engineering v TABLE OF CONTENTS Page LIST OF TABLES ..............................................................................................................xi LIST OF FIGURES ..........................................................................................................xiii LIST OF ABBREVIATIONS............................................................................................. xv CHAPTER 1: INTRODUCTION ........................................................................................1 1.1 Scope of Work............................................................................................................. 1 1.2 Changes in FGD Material Production ........................................................................2 1.3 Abandoned Mine Lands in Ohio................................................................................. 3 1.4 Leaching Experiments ................................................................................................6 1.5 Life Cycle Assessment ...............................................................................................8 1.6 Outline of Chapters..................................................................................................... 9 CHAPTER 2: ABANDONED MINE LANDS AND FGD MATERIAL UTILIZATION IN OHIO ............................................................................................................................11 2.1 History of Mining and Legislation in Ohio ..............................................................11 2.2 History of FGD Material Production in Ohio........................................................... 15 2.3 FGD Material Usage at Mine Sites........................................................................... 22 2.3.1 Otsego Gob Pile .................................................................................................24 vi 2.3.2 Fleming Surface Mine........................................................................................ 24 2.3.3 Freeport Gob Pile ...............................................................................................25 2.3.4 Broken Aro Remining ........................................................................................26 2.3.5 Roberts-Dawson Injection Project .....................................................................26 2.3.6 Rehoboth Refuse Pile .........................................................................................27 2.3.7 Rock Run Gob Pile............................................................................................. 28 2.3.8 Central Ohio Coal Company Coal Refuse Impoundment .................................28 2.3.9 Conseville Prep Plant Refuse Pile...................................................................... 29 2.3.10 Conesville Highwall......................................................................................... 29 2.3.11 Summary of AML Sites.................................................................................... 30 CHAPTER 3: CHEMICAL AND PHYSICAL PROPERTIES OF FGD GYSPUM ........32 3.1 Chemical Properties.................................................................................................. 32 3.1.2 Mercury.............................................................................................................. 35 3.1.3 Boron.................................................................................................................. 36 3.1.1 Elemental Analysis............................................................................................. 37 3.2 Physical and Mechanical Properties .........................................................................40 3.3 Overview of Leaching Experiments .........................................................................41 3.4 Methodology ............................................................................................................41 3.4.1 Toxicity Characterization Leaching Procedure ..................................................41 vii 3.4.2 Synthetic Precipitation Leaching Procedure ......................................................42 3.4.3 Integrated Framework ........................................................................................43 3.4.3.1 Tier 1 ..........................................................................................................43 3.4.3.2 Tier 2 ..........................................................................................................43 3.4.3.3 Tier 3 ..........................................................................................................45 3.4.4 Chemical analysis ..............................................................................................47
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