Rare Earth Elements: A Review of Production, Processing ...

More documents

Recommendations

Info

Rare Earth Elements Review Section 3 – Life-Cycle Stages of Rare Earth Elements Mines a b c Table 3-1. Numbers of Existing Mines by State Where Potential REE Resources Have Been Reported (see Appendix B for References) State Placer Mine or Sedimentary Deposit a Open Pit or Underground - Unspecified a, b Existing Open Pit Existing Open Pit with Underground Works Existing Underground Mine Total Mines/ Deposits by State Alaska (9) (5) 1 0 0 15 Arizona 0 (2) 0 0 0 2 Arkansas 0 1 0 0 0 1 California (1) 2 1 0 0 4 Colorado 0 (3) 1 0 0 4 Florida c 2, (4) 0 0 0 0 6 Georgia c 1, (4) 0 0 0 0 5 Idaho 7,(15) (2) 4 1 0 29 Illinois 0 (1) 0 0 0 1 Missouri 0 0 0 0 1 1 Montana 0 1, (3) 0 0 0 4 Nebraska 0 (1) 0 0 0 1 Nevada 0 1 0 0 0 1 New Jersey 0 0 0 0 1 1 New Mexico 0 (6) 4 1 0 11 New York 0 0 0 0 1 1 North Carolina 1, (1) 0 0 0 0 2 Oregon 0 (1) 0 0 0 1 South Carolina 1, (2) 0 0 0 0 3 Tennessee 1, (5) 0 0 0 0 6 Texas 0 1 0 0 0 1 Utah (1) 0 0 0 0 1 Virginia 1 1, (1) 0 0 0 3 Wyoming (5) (5) 0 0 0 10 Totals: 61 37 11 2 3 113 Numbers in parentheses indicate that a record of an existing mine was found, but that the type of mine was not specified; numbers in parentheses are known occurrences. Mines assigned to this category are for igneous or metamorphic deposits and not placer or sedimentary deposits. A few mines extend across state boundaries between Florida and Georgia. 3.3.2.4 Mine Closure The closure of a mine refers to cessation of mining at that site. It involves completing a reclamation plan and ensures the safety of areas affected by the operation; for instance, by sealing the entrance to an abandoned mine. EPA requires that planning for closure is ongoing for mines located on federal lands and not left to be addressed at the end of operations. The Surface Mining and Control Act of 1977 states that reclamation must “restore the land affected to a condition capable of supporting the uses which it was capable of supporting prior to any mining, or higher or better uses.” 3-18
Rare Earth Elements Review Section 3 – Life-Cycle Stages of Rare Earth Elements Mines In some cases, reclamation may not be possible to a level that would support past uses, and long-term monitoring and management may be required. Mines close for a variety of reasons, including economic factors due to a decline in the market value of the metal; geological factors such as a decrease in grade or size of the ore body; technical issues associated with geotechnical conditions, such as mine stability or in-rush of ground water at rates too high to manage; equipment failure; environmental impacts; and community pressures (Laurence, 2003). Often, mines will not close but rather become idle, with plans for reopening when the market will support the venture. Idle mines can continue to cause a variety of health-related hazards and threats to the environment if not properly managed. While the mine is idle, the waste piles, the tailings ponds that are associated with the processing plant, and other mine areas must be stabilized and managed, potentially over many years. Mines can be adequately managed to avoid log-term problems; however, the pollution and contamination issues that generally require environmental management over the life of the mine can remain after mine closure, such as the following: • Sedimentation of surface waters • Effluent and drainage (e.g., due to heavy precipitation during the rainy season and snow melt) from the mine, storage piles, or tailings management areas that can impact downstream drinking water sources and aquatic habitat • Acid mine drainage (AMD) and enhanced acid rock drainage (ARD) that also effect aquatic habitat • Continued pumping of mine water and contaminant plume migration control pumping that causes drawdown of nearby aquifers • Contaminated dusts • Subsidence or collapse of tunnels and subsurface structures, which also represents a safety hazard • Hazardous materials remaining on-site (e.g., fuels, lubricants, other chemicals). These management activities must be planned for long after operations cease and the mine is closed. The risks associated with these impacts are discussed in Section 6. In the case of public lands the state or a land management agency has the final authority for concerting various regulatory authorities and overseeing mine closures. For example, EPA’s responsibilities may include but not be limited to; NPDES wastewater discharge permits for post-closure mining operations, Clean Water Act (CWA) and Resource Conservation and Recovery Act (RCRA) related permits required for wastewater or contaminant treatment options (if necessary), and CERCLA financial responsibility documentation. 3.4 Characteristics of Mining Waste Sources Mining wastes could be referred to as (managed) materials of concern and, in general, some materials are not considered wastes until a particular time in their life cycle. However, that is not to imply an absence of environmental risk from stockpiled or stored materials. Mined materials that are generated may only occasionally or periodically be managed as wastes. Often, these materials are used for various onsite or offsite purposes instead of being stored as wastes, although the volume of waste material can often exceed the demand for reuse alternatives. EPA evaluates the risks to human health and the environment from reuse of various types of industrial sector wastes, including mining; however, many of these studies are ongoing, and this report does not 3-19
Page 1 and 2: EPA 600/R-12/572 | December 2012 |
Page 3 and 4: Foreword The U.S. Environmental Pro
Page 5 and 6: Abstract Rare earth elements (REEs)
Page 7 and 8: Table of Contents List of Acronyms
Page 9 and 10: List of Tables 2-1. Abundance of El
Page 11 and 12: Rare Earth Elements Review List of
Page 13 and 14: Rare Earth Elements Review Section
Page 41: Rare Earth Elements Review Section
Page 93 and 94:
Rare Earth Elements Review Section
Page 95 and 96:
Page 97 and 98:
Page 99 and 100:
Page 101 and 102:
Page 103 and 104:
Page 105 and 106:
Page 107 and 108:
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Rare Earth Elements Review Appendix
Page 119 and 120:
Page 121 and 122:
Page 123 and 124:
Page 125 and 126:
Page 127 and 128:
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
show all

Rare Earth Elements: A Review of Production, Processing ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?