MTM & Mining Methods

8/3/2019 MTM & Mining Methods

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EXECUTIVE SUMMARY

Coal mining is the most important component of WestVirginias economy, accounting for the majority of jobs andeconomic activity and many counties. Wages in the coal industry

are some of the highest in the state and are usually double theaverage annual income provided by other occupations. Taxes paidby the coal industry provide the largest component of statesrevenue base and support essential social and welfare programsadministered by state and local governments (additional economicinformation is provided in attachment 1). Because of the overallimportance of the coal industry to the overall welfare of WestVirginia it is critical that underground and surface coal miningcontinue in the Mountain State. Fill construction is an absolutenecessity for coal mining and other forms of development to

proceed in West Virginia.

All forms of coal extraction, underground and surface,invariably rely on some form of fill construction to facilitate removalof the mineral resource. These fills, which are highly engineeredand regulated, are usually constructed in small, ephemeral andintermittent stream courses.

Figure 1Typical Appalachian Ephemeral Stream


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Figure 2Typical Appalachian Intermittent Stream

The construction of fills is not unique to the mining industry inWest Virginia or Appalachia. The steep, rugged terrain of theregion has provided limited areas for development or constructionof any kind. What little flat land that does exist in West Virginia isconfined to the floodplains of rivers and creeks and is usuallyoccupied by roads, railroads and highways. New construction ordevelopment, mining or otherwise, will require some form of streamimpacts and fill construction.

Figure 3Compressed Nature of Development in West Virginia: All the Useable Land Between

Steep Mountains has Been Developed


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Figure 4Retail Center in West Virginia Constructed on a Mountaintop Using Valley Fills

Figure 5Federal Highway Construction in West Virginia


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Figure 6Fill Constructed in Connection with Highway Development

Figure 7Photo of Highway Construction (Background) and New Residential and School

Development Site (Foreground)

As noted previously, all forms of mining in West Virginia require theconstruction of fills. In underground mining, fills are required toprovide access to the coal seam for miners and the coal extractionmachinery. Underground mines also require the construction of a


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flat area or bench for the construction of essential supportstructures such as bathhouses, ventilation devices (fans), raw coalstorage areas and electrical installations. Additionally, coalextracted using underground mining techniques must be cleanedon the surface at a preparation plant. Coal seams in Appalachiatypically contain non-coal materials that lay within, above or below

the coal seam. This material is mined along with the coal inunderground mining and is mechanically separated from the coal atthe preparation plant. The leftover material is placed in an adjacentrefuse fill or impoundment.

Figure 8Underground Mine Access Road, Deep Mine Entries and Bench in West Virginia

Constructed on Fills


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Figure 9Coal Refuse Fill at an Underground Mining Complex

At surface mines, fills are required as a result of the swell factorthat occurs when rock and soil is excavated to uncover coal seams.Most of the rock and soil that is excavated to allow removal of thecoal is returned to the mined area as the first step of minereclamation in a process known as backfilling. Backfilling alsorestores the pre-mining contours and appearance of the mined areato mirror the surrounding, undisturbed topography (surface miningis explained in more detail in subsequent sections).

Figure 10Diagram Explaining Swell Factor of Overburden Following Excavation.


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Figure 11Valley Fill Construction at an Active Surface Mine

Figure 12Reclaimed and Revegetated Surface Mine and Valley Fills

Fills are a necessary component of all forms of development inAppalachia and West Virginia and any actions that restrict theseneeded fill structures will restrain if not stop this samedevelopment. Prohibitions or restrictions on mining-related fill


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structures will cripple both the underground and surface coalmining industry in West Virginia and Appalachia.

Because West Virginias economy, both state and local, is sodependent on revenues and taxes from the coal industry, anydecline in the industry will have a resulting negative impact on the

state. If the construction of fills are restricted, coal mining will berestricted and the efects on the economy of West Virginia will bedevastating. The severity of the economic impacts increase as fillsare further restricted and coal production is further reduced as theability to mine coal, surface or underground, is dependent on fills.

Recent mining engineering studies conducted as part of aprogrammatic Environmental Impact Statement on surface mining inAppalachia provide more detailed and exact evidence with respectto fill prohibitions:

Limiting valley fills to ephemeral streams resulted insignificant or total loss of the coal resource for 9 of the11 mine sites when compared to the original mine siteplans. All of the coal resource was lost for 6 of the 11mine sites. 1

A recent study in the central Appalachian coalfieldsindicated the draconian efects that prohibiting all

mining [in intermittent and perennial streams] couldhave on our nations energy supply. Assuming thatmining activities could not be conductedthis OSM[federal Oce of Surface Mining] study has estimatedthat 92.5 percent of the available coal reserves in theCentral Appalachian coal fields could not bemined.2

In response to a 1999 judicial decision that would have limited fillconstruction (later overturned on appeal) the West Virginia

Legislature commissioned a study of the economic and socialconsequences of limiting coal production:

1 Programmatic Mountaintop Mining /Valley Fill Environmental Impact Statement. EPA, OSM, Corps,F&WS and WV DEP. Mountaintop EIS Technical Report. Pg 1. 2000.

2 U.S. Department of the Interior, Office of Surface Mining Reclamation and Enforcement. Environmental Assessmentfor Rulemaking on Stream Buffer Zones and Excess Spoil, RIN 1029-AC04. pg.15 . 2004.


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Theanalysis considers two scenarios that are bothwithin the realm of reason. In the first of these twoscenarios, surface mining is gradually reduced, ascurrently permitted mines are retired and no newsurface permits are granted. Even under this restrictedscenario, the economic efects on the counties that

comprise the study region are likely to be devastating.Total regional employment is predicted to decline by 4.3percent, while overall regional economic activity ispredicted to decline by $620 million within the firstyear. The economic impacts observed under theextreme scenario, in which the Haden decision leads tothe immediate curtailment of surface mining, are evenmore extreme. A sudden cessation in surface mining ispredicted to cost the study region more than 10,500jobs, $281 million in incomes, and $1.8 billion in totaleconomic activity. 3

In summary, fill construction is an absolute necessity for any formof development or coal mining activity to take place in Appalachiaand/or West Virginia. The continued ability to construct these fillsin connection with coal mining activities is critical to the economicand social well-being of West Virginia.

The detailed sections that follow are intended to provide a betterunderstanding of the methodsof coal extraction employed in WestVirginia and the fill structures that facilitate coal extraction.

A. WEST VIRGINIA COAL MINING METHODS

Coal continues to play an important role in supplying the

energy needs of the United States and, more than any otherdomestic fuel resource, helps to assure this countrys energyindependence by providing a reliable, domestic source forelectricity generation and industrial consumption of energy. Coal isAmericas most abundant fuel resource and it is provided to the

3Marshall University- Center for Business and Economic Research. Coal Production Forecasts and Economic ImpactSimulations in Southern West Virginia: A Special Report to the West Virginia Senate Finance Committee. pg. 37.2000.


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market by a highly-trained and specialized workforce. Coal miningin the United States is also heavily regulated by matureenvironmental regulatory programs, including a specific federalstatute directed specifically at coal mining. The federal SurfaceMining Control and Reclamation Act (SMCRA), (30 U.S.C. 1201,et.seq.) expressed the importance of coal mining to the future

economic security of the United States when stating Congressionalintent:

Surface and underground mining operations afectinterstate commerce, contribute to the economic wellbeing, security and general welfare of the Nation andshould be conducted in an environmentally soundmanner.4

It is the purpose of this chapter toassure that coalsupply essential to the Nations energy requirements,and its economic and social well-being is provided andstrike a balance between protection of theenvironmentand the Nations need for coal as anessential source of energy. 5

West Virginia is the nations second largest coal producingstate. Coal mining operations in West Virginia produced over 161million tons of coal last year. West Virginia coal is used extensively

by domestic utility companies to produce electricity. Metallurgicalcoal mined in West Virginia represents some of the highest qualitycoal found anywhere in the world, and both domestic andinternational steel companies rely on this coal to produce coke foruse in the iron making process.6

Coal extraction in West Virginia is accomplished generally byunderground or surface mining. Both methods of coal extractionrequire the placement of fill structures, commonly referred toas valley fills, acknowledging the steeply-sloped terrain that

exists in West Virginia, within CWA section 404 jurisdictionalwaters. Construction of these valley fills necessitates section 404authorization from the Corps of Engineers (Corps).

4 Surface Mining Control & Reclamation Act, 30 U.S.C. 1201(j).

5 Surface Mining Control & Reclamation Act, 30 U.S.C. 1201(f).

6 See Generally Attachment 1, coal production statistics for West Virginia.


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A.1 UNDERGROUND COAL MINING

Underground mining techniques, which account for themajority of West Virginias coal production, utilize machinery todrive tunnels under the surface of the land. These tunnels are

situated in coal seams so as the machinery advances furtherunderground, coal is removed. Using a combined system of vehiclehaulage and conveyor belts, the coal extracted from the seam istransported to the surface. Underground mining is practical fromengineering and safety standpoint for coal seams that are locatedmore than 100 feet below the surface of the land. Undergroundmining in shallower coal reserves will often encounter mine roofintegrity problems as the geology and overburden at such shallowdepths is less consolidated and more susceptible to cracking andfailure (roof falls) than the strata above deeper coal seams.

Underground mines are usually characterized by the way thecoal seam is accessed from the surface and the undergroundextraction method used to mine the coal. The method foraccessing a coal seam for underground extraction is largelydependent on its vertical position relative to the surface. The threemethods of underground mine access are summarized in Figure A.1.

Figure A-1.Methods of Entry to Underground Coal Mines


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An individual underground mine may have more than one of theseaccess methods, depending on the characteristics of the individualcoal seam, the coal haulage system used at the mine, theventilation, roof control and safety plans for the mine and themines supply and employee transport considerations.

Underground mining coal extraction methods can generally bedivided into two categories: room and pillar mines and longwallmines. The type of extraction practiced is dictated by thecharacteristics of the coal seam and its related geology. Generally,longwall mining is restricted to seams with uniform geology andcoal seam thickness while room and pillar mining is more adaptableto seams with varying thickness, uniformity and geologic settings.

A.1.a. ROOM AND PILLAR UNDERGROUND MINING

Room and pillar mining is defined by the fact that portions of thecoal seam being extracted are left in place to support the roof ofthe mine. Room and pillar mines are developed by using machineryto extract the coal seam in a grid like pattern through thedevelopment of a parallel series of extraction areas referred to asentries. The entries are connected together by extracting the coalperpendicular to the parallel entries in crosscuts. To support thecoal extraction areas in the entries and crosscuts, roof support is

installed by using machines to install long bolts into the roof ofthe mining area to consolidate and tighten the overlying rockstrata. Referred to as roof bolting, this is the central point of amines roof control plan that is developed by safety regulatoryagencies and the operator to assure a maximum amount of safetyby minimizing the possible occurrence of roof fractures and slips orroof falls. Figure A-2 provides an illustration of typical room andpillar mine in Appalachia.


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Figure A-2.Room and Pillar Mining

Coal extracted from the entry and crosscut areas or working facesof the room and pillar mine is loaded onto special undergroundrubber tired haulage vehicles called shuttle cars. The shuttle cars

move the coal from the working face to a centrally-located conveyorbelt loading point where the coal is unloaded and transported tothe surface for processing at the coal preparation plant. Somemines use shuttle cars to move the extracted coal to a loading pointwhere it is transferred to narrow gauge railroad cars for movementto the surface. In slope and shaft mines there may also be a thirdtransfer point where the coal from the working face is transferredagain from the conveyor belt or rail car to an elevator-like haulagesystem where the coal is lifted vertically to the preparation plant.

The initial development of a room and pillar mine, whereentries and crosscuts are driven in the coal seam is referred to asprimary extraction. Mines using primary extraction only can usuallyrecover 40 to 60 percent of the coal in a given seam and reserve.Depending on the characteristics of the coal reserve, its overlyingstrata or roof and its underlying strata or floor, secondaryproduction may be possible in room and pillar mines. In secondaryproduction, some of the coal pillars that were established by the


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entries and crosscuts and were left in place for added roof controlare removed. Extraction of the coal in the pillars, if possible at all,is governed by roof control and safety conditions as extraction ofthe pillars usually results in some level of roof collapse. Where itcan be practiced secondary extraction is designed to remove thecoal resource in the pillars in a calculated and designed fashion to

allow for controlled roof collapse that will not endanger the safetyof coal miners or compromise the overall geologic integrity of theentire mine. Where it is possible, secondary extraction can allowfor recovery of 70 to 80 percent of the coal in a given coal seam.

A.1.b. LONGWALL UNDERGROUND MINING

The other major form of underground coal extraction islongwall mining. In longwall mines, equipment used in Room andPillar mining is used to develop two or three parallel entries in acoal seam. The longwall mine entries or headings are usuallyseparated by several hundred feet of solid coal. At a certaindistance advancing into the coal seam (depending on mine-specificgeology), the headings are connected by driving a crosscuts, or inlongwall mines, cross headings to connect the entries to form ablock of solid coal called a panel. Specialized equipment, known aslongwall machines, that are usually custom-built for specific minesthen begin extracting the coal along the face of the panel. Thesemachines include a shear or plow device mounted on a track that

moves back and forth across the panel cutting the coal with eachpass of the machine, referred to as the cutting head. As thecutting head extracts the panel of coal, the longwall machineadvances further into the coal seam extracting more of the seam asit advances through successive passes across the panel, allowingfor recovery of up to 85 percent of a given coal seam and reserve.The cutting head is attached to a special type of armored conveyorthat gathers the coal as it is cut by the head and moves it to aloading point where it is transferred to the main haulage system formovement to the surface and the coal preparation plant. Both the

cutting head and the special conveyor are protected by a specialform of hydraulic roof support devices known as shields. Theshields support the roof immediately above the longwall machineand are designed to advance as the cutting head moves deeper intothe coal reserve keeping the roof support parallel to coal face.Figure A-3 is a photograph of a longwall shear and Figure A-4provides an illustration of a Longwall mining system.


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Figure A-3Longwall Mining Machine with Shear Cutting Head

Figure A-4Longwall Mining Illustration

A.2 SURFACE COAL MINING

Surface coal mining techniques, which account for themajority of national coal production and roughly 42 percent of WestVirginias coal production, involve the mechanical removal ofoverlying native earth and rock or overburden to reach underlyingcoal seams. Surface mining can be further categorized into threebasic operational methods: contour mining, area mining andmountaintop removal mining. All three forms of surface miningare generally referred to as mountaintop mining. Secondary


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extraction methods can also be employed with surface mining,usually through a process known as highwall mining. While surfacemining includes a variety of methods, certain criteria used todetermine the exact operation, layout and the extent and form ofcoal extraction are applicable to all forms of surface mining.

Included in the criteria that are transferable to all forms ofsurface mining are mining and reclamation considerations. Beforeany permit is issued under SMCRA or a state delegated program,the operator must submit a specific mining and reclamation planfor review and approval by the regulatory authority. Thecomponents of the mining and reclamation plan include a variety ofissues such as initial mine development, final mine design,backfilling and regrading, achieving Approximate Original Contouror AOC (explained in greater detail in subsequent sections) anderosion and sediment control. Reclamation considerations, alongwith stripping ratios (explained in subsequent paragraph), areusually the dominant factors that dictate the form of surface miningthat is used to extract a coal reserve.

In addition to permitting considerations, determining theextent to which a coal seam or block of coal seams is economicallyfeasible for mining is an integral part of determining the method ofsurface mining used to extract the reserve. The typical method ofassessing surface mining economics for a coal seam is a calculation

of overburden (native rock and soil above a coal seam) moved perclean ton of coal produced, commonly referred to as mining ratio.The higher the mining ratio (or more overburden moved per cleancoal ton), the higher the cost of producing coal. In situations wherea given coal reserve includes more than one coal seam, therecoverable coal volume from the multiple seams is factoredtogether to lower the overall mining ratio for the entire coal reserve.Because mining more than one seam lowers the mining ratio for amining project and increases its economic potential, it allows forextraction of coal seams that would be uneconomic to recover by

themselves.

The economic viability of a surface mining project, calculatedthrough the mining ratio, is highly mine and coal reservedependent. Site-specific factors such as overburden type and


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depth, excavation costs, coal value and overburden haulagedistances and costs are all considered in the development ofstripping ratios for a particular mine site and coal reserve.

The ability to construct valley fills is paramount to theeconomic and physical viability of a surface mining project. As

explained in more detail in the following sections, all surfacemining methods need valley fills for placement of excessoverburden. Without the ability to construct fills, surface miningbecomes physically impossible in the steep terrain ofAppalachia and West Virginia.

A.2.a. SURFACE vs. UNDERGROUND COAL MINING

The decision to develop a coal reserve using surface orunderground mining is governed by a combination of severalgeologic, safety, economic, physical, regulatory and engineeringconsiderations. For example, if a coal reserve is located very deepin the geologic column, surface mining is simply not a viablerecovery method. These coal seams, which are typically accessedusing slope or shaft entries (see Figure A-1), can only be recoveredusing underground mining methods. The deeper the coal reserve,the less likely that it can be recovered using surface miningmethods. Coal seams that are thin or less than three feet thickcannot be recovered using underground mining methods regardlessof the seams location in the geologic column (see Figure A-5).

However, the same seams, if located close enough to the surfacecan be recovered using surface mining methods. Conversely, coalseams that are located closer to the surface of the land and outcropalong high ridges may be thick enough for underground miningextraction but fail roof control considerations as they are too closeto the surface for efective roof control of unconsolidated strata.

Figure A-5 is a cross section diagram of the coal seamstypically extracted using surface mining methods in West Virginia.

The heights of the various coal seams are shown on the diagramclearly indicating that most of the seams are too thin for extractionby underground coal mining.


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Figure A-5Cross Section of Coal Seams Extracted Using Surface Mining Methods

Another consideration that generally governs the selection ofthe underground or surface mining methods to extract a given coalseam and reserve is the quality of the coal seam. Very few coalseams in Appalachia and West Virginia are comprised entirely ofcoal. Most of the recoverable coal seams in this region have small

seams of non-coal materials such as shale and clay that areimbedded within, above or below the coal seam. The presence ofthese non-coal materials in a coal seam afects the coals heatingvalues, air emission properties and other factors that generallyinfluence the usability of the coal. For example, the presence ofnon-coal impurities will afect a coals ability to meet air emissionstandards imposed on electric utilities and could make the coalunusable. Figure A-6 is an illustration of a typical seam inAppalachia showing the inherent non-coal impurities that existwithin the coal seam. In underground mining, all of this materialwould be extracted along with the coal.


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Figure A-6Illustration of Typical Appalachian Coal Seam Showing Non-Coal Impurities

Within the Coal

In surface mining extraction, these non-coal impurities can beseparated in the pit or separated from the coal by the surfacemining equipment, negating the need for a separate coalprocessing plant. In underground mining methods, it is impossibleto separate the shale, clay and other non-coal partings from thecoal seam as the mining machinery removes the entire coal seam-partings included- to maintain a workable height for miners andsometimes to achieve maximum roof stability. This raw coal mustbe cleaned on the surface at the coal processing plant. The need toclean virtually all underground mined coal at a coal processing plantadds considerably to the cost of underground mining.

A.2.b. CONTOUR SURFACE MINING

Contour mining is practiced in areas where it is uneconomicalto remove all the overburden from a coal seam or series of coalseams. In contour mining, surface mining machinery follows thecontours of a coal seam or seams around a ridge excavating theoverburden and recovering the coal seam or seams as a contourbench around the mountain is created. Excavation proceeds inwardtowards the mountain to a pre-determined depth. Contour miningresults in excavation areas or contour cuts that wrap aroundmountaintops or ridgelines parallel to the contour of a given

mountain or ridge line. Contour cuts may be conducted on multipleseams on a ridge or mountain side, stepping upward in elevationmuch like a layer cake pattern. In multiple seam contour mining,the cuts for multiple seams extend deeper into the mountainsidemoving upwards towards the ridge top. Figure A-7 is a photographof an active contour mine in West Virginia. The photograph inFigure A-8 shows active contour mining along with reclaimed areas.


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Figure A-7Contour Surface Mine in West Virginia

Figure A-8Active Contour Surface Mine in West Virginia with Initial Reclamation Visible in

Distance

As coal removal proceeds around the mountain side, theexcavated material from new overburden cuts is used to backfill theprevious mining area to restore the pre-mining contours of the land


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or Approximate Original Contour (AOC). Figure A-9 is aphotograph of a former contour mine that is in the first stage ofreclamation. Overburden has been returned to the mining area andit is ready for compaction. In Figure A-10 the reclamation area hasbeen graded, seeded and initial vegetation has been established.

Figure A-9Initial Reclamation of a Contour Surface Mine

Figure A-10


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Regrading and Seeding of a Reclaimed Contour Surface Mine

In final reclamation, the initial vegetation has been succeededby mature and successful tree growth. The existence of a now-reclaimed contour mine in Figure A-11 is discernible only becauseof a slight diference in tree height between the reclaimed minebench and the undisturbed, existing topography and vegetation.

Figure A-11Reclaimed Contour Surface Mine

A.2.c. AREA SURFACE MINING

Area mining takes place over a ridge or mountainside and isnot restricted, as is contour mining, to the side of a mountain. Areamining occurs in locations where lower slopes and the presence ofmultiple coal seams produce mining ratios that allow for coalextraction across topography rather than around it (as in contourmining). Although area mining may afect a larger area than

contour mining, with coal extraction across an entire ridge ormountaintop, it is not considered mountaintop removal mining,because all the coal seams may not be recovered and the miningarea must be restored to AOC. Figure A-12 is a photograph of anactive West Virginia area mine.


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Figure A-12Active Area Surface Mine in West Virginia

Area mines may deploy mining equipment excavatingoverburden and recovering coal in a cross ridge approach, wheremining advances parallel to the long axis of a ridge. Area minesmay also be designed to advance mining through a cross ridgeapproach where equipment excavates perpendicular to the longaxis of a ridge. Both approaches and several areas of advancingcoal overburden excavation and subsequent backfilling may be

present on a given mining operation to take full advantage of localtopography to maximize production and reduce coal andoverburden haulage distances.

As with contour mining, overburden from the new mining cutsis used to backfill previous mining areas and restore AOC.Reclamation of an area mine follows the same general progressionas a contour mine. The mining area is backfilled and regraded torestore AOC. The area is seeded and initial vegetation is

established. Final reclamation involves substantial tree growth.Figure A-13 depicts the phases of area mining and reclamation withactive mining visible in the distance, initial reclamation in themiddle of the photograph and late reclamation with treesestablished in the foreground. Figure A-14 is a photograph of thesuccessive stages of area mining with active mining, earlyreclamation and late reclamation all visible in the picture. FiguresA-15, A-16 and A-17 depict area mines in the various successivestages of reclamation.


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Figure A-13Mining and Reclamation Phases of an Area Mine in West Virginia

Figure A-14Initial Reclamation of an Area Mine: Backfilling and Regrading to Restore AOC


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Figure A-15Early Reclamation of an Area Mine: Regraded Area Has Been Seeded and Initial

Vegetation Established

Figure A-16


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Late Reclamation of an Area Mine: Regraded Area with Vegetation Establishedand Tree Growth

A.2.d. MOUNTAINTOP REMOVAL SURFACE MINING

Mountaintop removal mining (MTR) is a special form of areamining where complete coal seams are recovered between a givenridge or mountaintop down to a basal coal seam or lowestelevation of coal extraction. The mining sequence for MTR isbasically the same as area mining, although the operational areasare generally larger and reclamation leaves a flat or gently rollingterrain versus the AOC restoration of area mining.

In the press and as used by anti-mining groups the termmountaintop removal mining is used more broadly than its

SMCRA statutory definition to include all forms of surfacemining in Appalachia and West Virginia. It is very important tonote that for a mining site to be considered a MTR miningoperation it MUST fit the narrow SMCRA definition of a surfacemining operation that removes all of the coal seams in a givenridge and DOES NOT restore the mining area to AOC.

As noted above, MTR mining operations do not restore AOCas do contour and area mines. Reclaimed MTR mines generally

have lower slopes and elevation than the original topography. Theability to obtain a variance from AOC restoration (and change anarea mine to a MTR mine) is dependent on the intended post-mining land use (PMLU) of the former mining area. The PMLUs thatwill qualify a site for a variance from AOC restoration areenumerated in SMCRA and the corresponding state programs (moredetail on these PMLUs is provided in the section on miningregulation). Generally, the approval able PMLUs for MTR mines arelimited to commercial, industrial, residential or agricultural uses. In

the steeply-sloped terrain of Appalachia and West Virginia, thepotential for PMLU development has emerged as a solution tochronic economic problem in the region- the lack of land, outsideof flooding zones with needed infrastructure that is suitable fordevelopment (see Figure 3). Figures A-17 through A-23 arephotographs of PMLUs developed on former MTR mining sites.


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Figure A-17Former MTR Mine with Golf Course as Approved Post Mining Land Use

Figure A-18


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Another View Former MTR Mine with Golf Course as Approved Post Mining Land

Use

Figure A-19Former MTR Mine with Developed as an Airstrip

Figure A-20Former MTR Mine with Light Industrial PMLU (Wood Products Plant)


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Figure A-21Former MTR Mine with Residential Development

Figure A-22Hospital and School Construction on Former MTR Mine Site


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Figure A-23Retail Center Developed on Former MTR Mining Operation

A.2.e. AUGER & HIGHWALL SURFACE MINING(Secondary Coal Production on Surface Mines)

As noted in previous sections, secondary coal production ispossible on surface mining operations through various methods ofauger or highwall mining. Both auger and highwall mining activitiesare conducted after the economic threshold imposed by thestripping ratio for a particular mine is achieved and no furtherexcavation of overburden is possible. Auger and highwall miningallows for additional coal extraction in individual coal seams alongthe highwall once the maximum depth of excavation is reached ona surface mine. These mining activities (if used) are the last to beconducted in a mining extraction area before backfilling, regradingand AOC restoration commences as the first stage of reclamation.

In auger mining, holes are drilled into the exposed coal seamoutcrop by augers driven by rotary shafts and hydraulic rams. Thecoal is removed by the advancing auger through a screw-likeaction. Mining augers may come in single, double or triple headmachines. Augers are generally limited to advancing and removingcoal to a depth of 200 feet into the coal seam. Augers typicallyhave a recovery rate of 33 percent of a given coal seam. As the


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auger reaches the maximum depth of penetration into the coalseam it is withdrawn from the highwall and moved further along theoutcrop to being the extraction process again. Figure A-24 is anillustration of a typical auger mining system.

Figure A-24Auger Mining System Extracting Coal from the Highwall of Surface Mine

As coal is produced from the auger mining machine it is stockpiledand loaded into haulage trucks.

Much more common than auger mining as a means ofsecondary coal production on surface mines are highwall miningsystems. These mining systems use continuous mining machinessimilar to those used in underground mining methods to drive aseries of entries into a coal seam outcrop along a surface minehighwall. As the highwall mining machine advances into the coalseam its cutting head removes the coal and directs it to specialized

conveyor cars that are coupled to the machine. These conveyorcars deliver the coal to the surface where it is stockpiled andloaded. As the maximum depth of coal extraction is reached themining machine is withdrawn from the highwall and the system ismoved further along the outcrop to drive a new entry. Highwallmining systems have a better recovery rate than auger machineswith up to 45 percent of coal seam being extracted. Figures A-25


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and A-26 are photographs of highwall mining systems at work onsurface mines in West Virginia.

Figure A-25Highwall Mining System on an Area Mine in West Virginia


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Figure A-26A Highwall Mining System on an MTR Mine in West Virginia. To the Right of the Picture

are the Specialized Conveyor Cars that Follow the Highwall Mining Machine into the CoalSeam

A.2.e. MINING COMPLEXES(Synergies Between Underground and Surface Mining)

The various surface and underground mining methodsdescribed in Section A rarely exist in a vacuum as single sources ofcoal production. Instead, several diferent forms of mining providecoal to centrally located preparation plant and coal loading facility(such as a railroad car loading facility or loadout). Figure A-23

depicts a typical mining complex in West Virginia. Figure A-27 is acoal preparation plant and railroad loadout at a mining complex.


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Figure A-27Typical Appalachian Mining Complex

Figure A-28


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Coal Preparation Plant and Railroad Loadout at a West Virginia Surface andUnderground Mining Complex

The use of several diferent mining methods at a complex isindicative of coal seam characteristics and overburden geologypresent in West Virginia. As previously explained in Section A,these factors dictate whether coal seams will be removed usingunderground or surface mining techniques. Additionally, the abilityto separate impurities from coal mined using surface miningmethods in pit ofsets the higher costs associated with cleaningvirtually all the coal from underground mining. Thus, lower costsurface mining production ofsets the higher cost of undergroundproduction, making the underground mines associated with miningcomplexes economically viable.

Surface mines further ofset the economic disadvantages of

underground mining because of greater flexibility to meet changingmarket and customer needs. Surface mines in Appalachia typicallyextract more than one coal seam and coals can be cleaned andblended in the pit, providing options for coal producers to respondto changing coal markets and customer quality specifications.Recent reviews by the federal agencies that regulate coal mininghave acknowledged the interrelationship between underground andsurface mining:

Many mines rely on blending the products of diferent

surface mines or a combination of surface andunderground coal to conform with supplycontracts for particular coal quality. Also, transportation and coal preparation costs associated withsmaller underground mines are sometimes related tothe proximity of larger mines with this existinginfrastructure. If the infrastructure is not available, a new,smaller mine may not be practical. Therefore, thetypes and qualities of coal reserves available in various seams,

transportation, and coal cleaning facilities maydetermine mining viability.7

7 Programmatic Environnemental Impact Statement Page IV. I-4


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B. FILL CONSTRUCTION & COAL MINING

Coal extraction in West Virginia is accomplished generally byunderground or surface mining (explained in section A). Bothmethods of coal extraction require the placement of fill structures,commonly referred to as valley fills in acknowledgment of thesteeply-sloped terrain that exists in West Virginia, within CWAsection 404 jurisdictional waters. Construction of these valley fillsnecessitates section 404 authorization from the Corps of Engineers(Corps).

B.1. FILL CONSTRUCTION & UNDERGROUND COAL MINING

Underground mining techniques, which account for themajority of West Virginias coal production, utilize machinery todrive tunnels under the surface of the land. These tunnels are

situated in coal seams so as the machinery advances furtherunderground, coal is removed. Using a combined system of vehiclehaulage and conveyor belts, the coal extracted from the seam istransported to the surface. 8 In underground mining, it isimpossible to separate coal from the rock partings that lie above,within or below the coal seam. This inherent material is removedalong with the coal and transported to the surface. In order toprovide a saleable product that is free from these impurities, theserock partings are removed from the coal in a preparation plantusing combined mechanical and chemical separation procedures:

Underground mining methods extract everything withinthe coal seam and sometimes several inches of top orbottom rock. Raw coal from most deep mines todayactually contains only about 50 percent coal by weight.The remainder is actually in-seam impurities or out-of-

8 See Generally Underground Mining Methods, pages III-I.3-11, Draft Programmatic EnvironmentalImpact Statement. Corps, EPA et.al. 2005.


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seam dilution that must be separated from the coal toproduce a marketable product. 9

Figures B.1 and B.2 are photographs of typical preparation plants.

Underground mining may also involve excavating non-

coal waste rock underground. Because undergroundmining typically brings this waste rock material to thesurface, the mine operator typically constructs fills toaccommodate the material. 10

Figure B-1Coal Preparation Plant and Railroad Loadout.

9Bragg v. Robertson. Report of O. Eugene Kitts, 1998



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Figure B-2Coal Preparation Plant

Once removed from the coal, these partings, now referred toas coal refuse, are placed in engineered and permitted structuresreferred to as refuse fills. Figure B-3 is a photograph of a coalrefuse fill.


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Figure B-3Coal Refuse Fill at an Underground Mining Operation in West Virginia

In some cases the coal refuse is used to construct anembankment of a dam that serves as a source of water used in thecoal preparation plant process. Known as coal refuse dams, thesestructures along with refuse fills, are subject to the requirements offive separate regulatory programs and are designed to the strictestengineering standards to assure their stability and safety. Inaddition to the CWA section 404 permitting and mitigationrequirements, these structures are permitted and reviewed by thefederal Mine Safety and Health Administration, the West VirginiaDepartment of Environmental Protection (both the mining and waterresources programs), and the federal Oce of Surface Mining

Reclamation and Enforcement. Figure B-4 is a photograph of anactive coal refuse impoundment. Figures B-5 and B-6 arephotographs of a coal refuse impoundments that are beingreclaimed. Note that the face of the embankment has been seededand the impounding capacity of the structure is being eliminated.


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Figure B-4Active Coal Refuse Impoundment

Figure B-5Coal Refuse Impoundment Being Reclaimed. The Face of the Embankment is Seeded and

the Impounding Capacity of the Structure is Being Eliminated


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Figure B-6Coal Refuse Impoundment in Late Reclamation. Tree Growth is Evident on the Face of

the Embankment.

Most, if not all of the coal removed using underground miningtechniques must be cleaned in the preparation plant process beforeit is shipped to consumers, making coal refuse fills and dams vital

to the continued existence of the underground mining industry inWest Virginia and the country:

Whatever is not shipped to a [coal] customer from apreparation plant goes into a refuse disposal facility. Itis not unusual for a plant to handle over 1,000 tons perhour of coal refuse. An operation of that magnitudemust have access to a large disposal site withinrelatively close proximity to the plant. Without theability to construct valley fills for coal refuse disposal,deep mining in West Virginia would become virtuallyimpossible.11

In addition to the required refuse structures, underground

mining operations in West Virginia fall under the jurisdiction of thesection 404 program because of the pre-mining construction

11Bragg v. Robertson. Report of O. Eugene Kitts, 1998


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activities that are necessary to provide access to the coal seam. Theinstallation of an underground mine generally requires theconstruction of a valley fill as rock and earth is removed from themountainous area and a flat area, or bench is created that allowsaccess to the coal seam and provides an area for criticalunderground mining infrastructure such as bathhouses, electrical

power installations, access roads and underground ventilationfacilities:

Development of underground mine portal facilities insouthern West Virginia often requires the construction ofvalley fills for permanent disposal of excess material andfor temporary storage of mine face-up spoil. A typicalsmall deep mine installation includes a portal benchexcavation, a stockpile bench cut into the hillside, and avalley fill as close to possible to provide spoil storageand to serves as a parking and supply storage area.12

Underground mining development involves excavatingrock and soil on the surface to expose the coal seam andto provide access for people, equipment andventilation for the underground mining operation. Thisprocess is referred to as facing up. In steep terrain, excavated material from these face-up areas may

result in small fills if the excavation is limited toproviding coal seam access, or larger fills if facilitiessuch as miners bathhouses, oce buildings, andcoal storage or coal preparation areas are needed. 13

In addition to the face-up areas, underground mines requiresection 404 permits for the construction of in-stream ponds tocontrol the runof from the mining area:

In order to minimize sedimentation and comply with

CWA [Clean Water Act] or state euent standards, anoperator of a surface or underground mine may need to

12Bragg v. Robertson. Report of O. Eugene Kitts, 1998.



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place sediment control structures or ponds in streamsbelow the mine.14

Figure B-7 is a photograph of an underground mining complex inWest Virginia. This particular operation accesses the coal seam with

a slope entry. As the photo indicates, section 404 authorizationwas required to provide room for the deep mine slope, supportingfacilities such as the equipment shop, bathhouse, ventilation fansand raw coal staging area. In this particular case a large culvertedfill was constructed to provide the underground mine bench.

Figure B-7

Underground Mining Operation in Southern West Virginia Showing Surface Facilities thatNecessitate Stream Impacts and Section 404 Authorization.

B.1. FILL CONSTRUCTION & SURFACE COAL MINING



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Surface coal mining techniques, which account for themajority of national coal production and roughly 38 percent ofWest Virginias coal production, involve the mechanical removal ofoverlying native earth and rock or overburden to reach underlyingcoal seams. While surface mining includes a variety of methods,the overall objective is the same: coal extraction through surface

removal of overburden. Under any method of surface mining, mostof the excavated overburden is returned to the mined-out areas toeliminate the contours of the mineral extraction areas. Referred togenerally as backfilling, this restoration eliminates the contoursand appearance of the mined areas such as coal pits and highwallsand restores the approximate original contour (AOC) or the original,pre-mining topographic contours and appearance of the area.However, not all of the overburden can be returned to the originalareas due to the swell factor of the native rock and soil. Thisexcess overburden is typically placed in valley fills that areconstructed in jurisdictional waters. The need for fills results fromthe swell factor- the physical expansion of the fractured rock andsoil- which can increase its volume by 15-40 percent:

The primary reason for using valley fills is thatexcavation of overburden results in a greater volume ofmaterial than was present on the mine site beforemining. When bedrock is broken up forming spoil, voidspaces are left between the individual rock fragments,causing them to occupy a greater volume than theoriginal, unbroken rock. This expansion is referred toas swell and typically represents a volume increase ofabout 40 percent. Compaction of soil during backfilling

partially ofsets swell as the rock fragments aresqueezed together by the weight of overlying material,but this shrinkage factor will not completely return thespoil to its solid or bank volume. 15

Figures B-8 and B-9 illustrate swell, shrinkage and bulking factors.

15 Programmatic Environmental Impact Statement. Corps, EPA et.al. 2005. Page III.K-3, Swell Factor andExcess Spoil.


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Figure B-7Diagram Explaining the Swell, Shrinkage and Bulking Factors of Overburden Following

Excavation.


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Figure B-8Cross Section Diagram of Mining Site that Illustrates Physical Configuration and Swell,

Shrinkage and Bulking Factors

As illustrated by the diagrams above, the backfilling and regradingprocess of mine reclamation to restore AOC can reduce the swellfactor of overburden this shrinkage factor, typically by 15 percent.The diference between the swell and shrinkage factors is referredto as the efective swell or bulking factor of the overburden. Thebulking factor of overburden can very depending on mine-specificgeology but in Appalachia the industry average is about 25 percent.This extra 25 percent material or excess overburden must beplaced in a stable, engineered manner. Because of the extremelysteep slopes that exist in Appalachia, over-stacking this materialto create ridges or mountains that are higher than what existed

before is not possible:

Particularly on steep-sloped mine sites, the excess spoilgenerated by the swell factor cannot be completelybackfilled on the mine bench without construction ofpotentially unstable slopes or substantial deviation fromAOC. The maximum amount of spoil that can bereturned to the mined bench is constrained by SMCRA


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slope stability and design requirements (i.e., the slope atwhich backfills can be constructed)16

Transporting the excess overburden material to a separate locationon another mountaintop or ridge is also impractical. Such sites aregenerally unavailable because of property constraints and any

placement of overburden on disturbed areas would significantlyalter the topography resulting steeper slopes that are unstable.The physical constraints imposed by steeply sloped, rugged terrainleaves only one available option for the placement of excessoverburden- valley fills.

Fill construction methods employed in surface mining weredeveloped to some degree prior to the passage of the SMCRA. Thetechnique was largely perfected by the mining industry and the pre-SMCRA mining regulatory authority in West Virginia. This practiceof controlled, engineered placement of excess overburden wassubsequently recognized by Congress in SMCRA and the federalOce of Surface Mining in its corresponding regulations.Additionally, the federal Environmental Protection Agency hasrecognized the environmental advantages of overburden placementin valley fills as early as 1979 and the agency conducted its firstEnvironmental Assessment on the practice in 1984. Valley fills havean excellent record of long-term stability as recently confirmed in amulti-agency programmatic Environmental Impact Statement.

Valley fills (and coal refuse fills and impoundments) are alsosome of the most heavily regulated, reviewed and engineered man-made structures in the world. As detailed in subsequent sections,mining-related fills are subject to host of federal and state laws andregulations that afect everything from fill site selection toconstruction and reclamation criteria to storm water runofdischarges.

The size of valley fills associated with mining (surface or

underground) has been the subject of much debate over the last 12years. Lost in most of these discussions is the fundamental factthat fills are constructed because of physical and geologic realitiessuch as swell factor that was described in detail in previoussections. Additionally, the size of fills associated with miningoperations has been addressed in West Virginia and other

16 Programmatic Environmental Impact Statement. Corps, EPA et.al. 2005. Page III.K-3, Swell Factor andExcess Spoil.


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Appalachian states with the adoption of formal AOC policies. Thesedocuments provide for an engineering and mathematical analysis todemonstrate that valley fills are as small as possible by maximizingthe amount of overburden that is returned to the mined area as partof AOC restoration. Also, West Virginias AOC policy has beenaccepted by the Corps and EPA as a demonstration of fill

minimization under the section 404 permit and review analysis.

Figure B-9Valley Fill Construction on an Active Surface Mine


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Figure B-10Early Reclamation of a Valley Fill- Compaction and Seeding

Figure B-11Reclaimed Valley Fill on an AOC Variance MTR Mine


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Figure B-12Valley Fill on a Reclaimed Area Mine


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Figure B-13Older Valley Fill on a Reclaimed Area Mine

C. ENVIRONMENTAL LAWS AND REGULATIONS GOVERNINGUNDERGROUND

& SURFACE COAL MININGOPERATIONS Coal mining is one of the most heavily-regulated industrialactivities that occurs anywhere in the world. Mining operationsmust obtain multiple permits from multiple state and federalregulatory agencies before coal extraction can begin. Thesepermits cover everything from basic geologic principles that governthe design of the operation, to the coal mining techniques andpractices used to recover the coal to the close out and finalreclamation of a mining site. The most important environmental

programs related to coal mining include the Surface Mining Controland Reclamation Act and various sections of the Clean Water Act.

C.1. SURFACE MINING CONTROL & RECLAMATION ACT

Passed by Congress in 1977, this all-encompassing regulatoryprogram addresses every environmental facet of surface andunderground mining operations. The Surface Mining Control and


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Reclamation Act (SMCRA), created an entire federal regulatoryprogram specifically for coal mining operations. SMCRA alsocreated a new federal regulatory authority, the Oce of SurfaceMining Reclamation & Enforcement (OSM), to permit and inspectmining operations across the country. SMCRAs permittingrequirements are comprehensive and require the submission of

detailed information regarding all aspects of mine design, operationand reclamation.

SMCRA also established a process by which states couldassume the primary authority for the environmental regulation ofmining activities through a process referred to as primacy. In aprimacy state, the permitting and regulation of mining operations ismaintained by a state environmental protection agency withoversight from OSM.

State primacy programs must meet the standards establishedunder SMCRA with respect to program stringency, permittingrequirements and environmental inspection frequency.

If a state fails to meet these SMCRA requirements, OSM canrevoke primacy and takeover the inspection and permitting ofmines within that state. West Virginia has primacy under thefederal surface mining laws and maintains its own set of detailedand comprehensive statutes and regulations.

The West Virginia Department of Environmental ProtectionsDivision of Mining & Reclamation (WV DEP) administers WestVirginias mining regulatory program. In addition to meeting therequirements of SMCRA, West Virginias mining regulatory programis considerably more stringent than the federal regulations. WestVirginia has more stringent controls on reclamation, post-miningland uses and disturbed areas than OSM or our surrounding states.West Virginia also has more stringent requirements on blasting,with an entire division of WV DEP dedicated solely to inspection and

monitoring of surface mine production and underground minedevelopment blasting.

In addition to regulating active mining, SMCRA imposes strictrequirements on reclamation of mined areas. For example, SMCRArequires that all surface mined areas be returned to approximateoriginal contour (AOC) unless a mine operator can demonstrate thatleaving a mine site configured with flat, or more gentle relief will


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lead to a beneficial post-mining land use such as industrial orhousing development.

SMCRA also requires that all mine operators furnish financialinstruments to guarantee the completion of reclamation and landrestoration following the completion of coal recovery. Coal

companies typically post bonds with the agency to cover the cost ofreclamation should an operator go out of business. Any shortfallbetween the actual cost of reclamation and the bonds is covered bya bonding pool that is funded with a tax on active coal production.The bonds are not released by the agency until the company hasdemonstrated compliance with the approved reclamation plan.

In addition to these program basics, recent changes to WestVirginias surface mining regulatory program are detailed in aseparate attachment to this section. These changes were made tospecifically address concerns related to surface mining operations.In most cases, these West Virginia revisions exceed therequirements mandated under SMCRA by OSM and the similarprograms in other states.

C.2. CLEAN WATER ACT

In addition to SMCRA, The coal mining industry is subject to

three separate regulatory programs established under the federalClean Water Act: The section 402 water discharge program, thesection 404 dredge and fill program and the section 401 waterquality certification programs. In addition to the information belowregarding the various regulatory programs under the Clean WaterAct, more detail on the implementation of West Virginias waterregulatory program is provided in a separate attachment thatdetails recent revisions to those programs.

C.2.a. CLEAN WATER ACT SECTION 402

Under section 402 of the 1972 Clean Water Act, coal mining iscategorized as a point source category meaning that alldischarges from mining operations must comply with established


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water quality euent limitations. Any and all discharges mustcomply with these euent limitations which are established byindividual states to protect the existing use of streams. Miningcompanies must obtain section 402 permits before initiating anyactivity that will result in a discharge to a stream. The majority ofthe discharges from coal mines are simply storm water runofs

which must be routed to a discharge point where compliance with asection 402 permit is monitored. The federal EnvironmentalProtection Agency has delegated administration of the section 402program to the State of West Virginia.

C.2.b. CLEAN WATER ACT SECTION 404

Section 404 of the Clean Water Act regulates the placement ofdredged or fill material into waters of the United States. Coalmining operations that result in the construction of valley fills orcoal refuse structures must obtain permits from the U.S. ArmyCorps of Engineers for these activities. The Corps, with oversightfrom the federal Environmental Protection Agency, administers thisregulatory program. The permit review for a section 404 activityincludes a detailed analysis of alternatives to assure that the sameactivity could not be accomplished without the placement of fillmaterial in streams. The section 404 regulations also require thatan applicant minimize the amount of fill material that is placed in astream.

C.2.c. CLEAN WATER ACT SECTION 401

Referred to as state water quality certification, section 401of the Clean Water Act is a state-administered program related tothe federally-administered section 404 program. Under section401 certification no placement of fill material can occur under asection 404 permit unless the state certifies that the placement ofthat fill material will not result in a violation of applicable statewater quality standards. In order to construct valley fills or coal

refuse structures, the coal industry must obtain section 401certification after the Corps has issued a section 404 permit.

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