Major Challenges in Landscape Planning: Simulated Field Trips

Surface Mining1

2/ Robert Leopold, Bruce Rowland and Reed Stalder

Abstract: The surface process consists of four phases: (1) exploration; (2) development; (3) production; and (4) reclamation. A variety of methods has been developed, including strip mining, auger, area strip, open pit, , and hydraulic. Sound planning and design techniques are essential to implement alternatives to meet the myriad of laws, regulations, and mining and visual resource objectives.

INTRODUCTION OVERVIEW OF SURFACE MINING

Our brief slide introduction of various Stated in the simplest terms, surface mining activities should reinforce your con- mining consists of removing the topsoil, , viction(s) that management of the visual and other strata called overburden that lie resource in conjunction with surface mining above mineral or fuel deposits to recover is a feasible and necessary undertaking. We them. have far too long stressed the negative; the time is now to stress the positive. When compared to underground methods, surface mining offers several advantages: it The purpose of this simulated visual (1) allows recovery of deposits which cannot field trip is to increase the audience's be deep-mined; (2) it usually results in a more (1) understanding of the surface mining complete recovery of the deposit; and process; (2) sensitivity to surface mining- (3) generally, lower cost per unit of related visual impacts; and (3) awareness of production. visual impact mitigation and design practices and planning techniques. The surface mining process generally consists of four phases: (1) exploration; (2) development; (3) production; and (4) reclamation.

The purpose of exploration or "prospec- ting" is to discover, delineate, and prove the ore body. Exploration techniques vary with the commodity and its geographic location. l/ Presented at the National Conference on These include remote sensing or on-site mapping, Applied Techniques for Analysis and Management core drilling to intersect deeper-lying ore of the Visual Resource, Incline Village, bodies, or excavating shallow trenches or pits Nevada, April 23-25, 1979 to expose the ore. For example, uranium ex- ploration in the West combines aerial geo- 2/ physical mapping and core drilling. Chief, Division of Planning and Environ- mental Coordination Colorado State Office During the development phase, detailed Bureau of Land Management, Denver, Colo.; mining and reclamation plans are developed, Landscape Architect, Valley access and haul roads are constructed, and Authority, Division of Natural Resources support facilities and structures are built. Services, Norris, Tenn.; State Landscape Architect, Utah State Office, Bureau of Production is a four-step process, Land Management, Salt Lake City, Utah. including: (1) site preparation to remove vegetation and other obstructions, and to prepare sites for spoil or waste disposal; (2) blasting and removing overburden; (3) excavating and

20 loading ore; and (4) transporting the ore to (3) Area strip mining is used in flat or a processing plant, storage area, or to market. rolling terrain where the deposits are exten- sive and lie relatively near the surface. A Reclamation involves restoring the land trench is made through the overburden, exposing to productive use and controlling on-site and the deposit which is then removed. As each off-site impacts. Reclamation problems and succeeding parallel cut is made, the spoil is techniques vary with the type of mineral, deposited in the previous cut. The final cut mining method, regional climatic differences, leaves an open trench and a highwall. Prior and regulations. to reclamation, the area from the air appears to have been subjected to a giant plow with For example, regulations which resulted furrows reaching a depth of 100 feet or more. from enactment of the Surface Mining Control Eastern phosphate, western , and some and Reclamation Act of 1977 require surface clays and iron ore are mined using this method. coal mines to be reclaimed back-to-approximate original contour. Successful reclamation In recent years, a combination of area depends in large part on accurate identifica- and contour strip mining methods called tion of the physical and chemical characteris- mountaintop removal has been employed to tics of the overburden and effective segrega- recover coal in southern Appalachia. This tion of material which will support re- method is often used when the coal lies establishment of vegetation. close to the ridge of the mountain, thus allowing economical removal of the overburden A variety of surface mining methods has above the entire seam. been developed to handle effectively the diversity of geologic, topographic, and (4) Open pit mining, also called - climatic conditions inherent in the location ing, is similar to area strip mining, but it of various minerals. These include: is generally conducted in a localized area (1) contour strip mining; (2) auger mining; resulting in large vertical pits. Unlike (3) area strip mining; (4) open pit mining; area strip mining, the amount of overburden (5) dredging; and (6) . removed is proportionately small compared with the quantity of ore recovered. In many (1) Contour strip mining is used in cases, large quantities of ore are obtained hilly or mountainous terrain where the within a relatively small surface area because mineral lies in beds or seams. The overburden of the thickness of the deposits. In addition, is removed beginning where the mineral outcrops open pit mines are generally in operation over on the surface and proceeds into the mountain much longer periods of time, often decades. until the cost of removing the overburden Limestone, sandstone, marble, granite, sand exceeds the value of the deposit to be re- and gravel, iron ore, , uranium, mica, covered. In the past, this unconsolidated sulfur, and some phosphate are mined using material was cast down the outslope as spoil. this method. Once exposed, the deposit is loosened and removed. This creates a bench on the mountain- (5) Dredging is a -oriented mining side with an associated highwall, sometimes operation that uses a suction apparatus or exceeding 100 feet in height, which marks the various mechanical devices such as buckets, lateral extent of overburden removal. This clamshells, and draglines mounted on floating process is continued generally on contour barges to recover the deposits. Tailing around the mountainside. Coal in Appalachia piles left at mine sites resemble spoil piles and phosphate in the West are mined using created during area strip mining for coal. this method. This technique is often used to mine and sand and gravel. (2) Auger mining is often performed in conjunction with contour strip mining. When (6) In hydraulic mining, a powerful jet the economics of mining stop the stripping, of water is used to erode a bank of earth or the operator sometimes chooses to extract gravel which is either the overburden or more of the deposit by boring horizontally contains the desired mineral. Ore- into the seam where it is exposed at the bearing material is fed into slurries or base of the highwall, like a carpenter bores other concentrating devices where the desired a hole in wood. However, it is an extremely product is separated from the wasteful technique. For example, augering coal (waste). Although extensively used in the may recover only 40 per cent of the seam, leaving past to mine gold, it is a practice that has the remaining 60 per cent in a condition that makes been virtually eliminated today. it unrecoverable by existing mining techniques. To date, an estimated 6.5 million acres of land, approximately 10,000 square miles

21 or roughly the size of Maryland, have been In the past, improper placement of over- disturbed in the United States by surface burden and topsoil, exposure of toxic materials, mining activities and associated access and inadequate drainage and revegetation have facilities. As of 1971, 90 per cent of this acreage resulted in many environmental impacts, in- was attributed to seven commodities: coal, cluding landslides, , stream siltation, sand and gravel, stone, copper, clay, phos- and acid mine drainage. phate, and iron ore. The current estimated rate of disturbance, which is 225,000 acres In the exploration phase, visual impacts annually, will increase in future years. are generally slight, due to the limited dis- turbance caused by drilling, trench excavating, Over 50 types of minerals and commodi- and access road development. ties are recovered by surface mining methods. Their nature, extent, and geographic distri- The visual impact of the mining process bution vary widely. For example, coal in becomes more intense in the development and different forms is found scattered throughout production phases due to the large amount of the eastern, midwestern and western portions land disturbance. of the United States in 34 states. Although one of the goals of reclamation As our society becomes more complex in is to reduce visual impacts, the visual con- its industrial and technological development trast between reclaimed areas and surrounding and needs increased energy sources and undisturbed areas often remains for many years. independence, the pressure to recover our natural resources will intensify. This Changes over time in the mining process inevitably means that surface mining will due to advances in technology (equipment) and greatly increase, not decrease in signifi- mining methods, and the influence of regula- cance in the coming decades. For example, tory laws and their enforcement have affected coal strip mining in Appalachia, recently the nature, extent, and duration of associated thought to be near an end, is only just surface mining visual impacts. Until the mid- beginning, considering development in mining 1960's, surface mining was largely uncontrolled technology and revived national coal produc- with little concern for the environment. tion goals. The challenge is to increase Between the mid-1960's and the mid-1970's, production efficiently while maintaining or surface mining states made enormous efforts enhancing environmental and visual quality. to regulate mining and reclamation activities by law. These laws concentrated on reducing environmental impacts, which indirectly VISUAL IMPACT AND SURFACE MINING lessened the severity of visual impacts. The back to contour provisions of the Surface The visual resource, like other earth Mining Control and Reclamation Act of 1977 resources, must be properly managed to main- are the strongest attempt to date to control tain acceptable standards of quality. Whether visual impacts of surface mining, although existing quality is enhanced or degraded is a they apply only to coal. function of the nature and extent of change to the landscape. Surface mining extensively changes the landscape through removal and/or VISUAL IMPACT MITIGATION relocation of vegetation and large quantities of earth. Changes in the land's natural form, Sound planning and design techniques are line, color, and texture that create contrast essential to implement creative alternatives between the mine and its surroundings consti- to meet mining objectives. These techniques tute the major visual impacts of surface must be viewed as principles or objectives mining. and not rigid standards with limited flexi- bility. Two specific components are generally Examples of these changes include: recognized. They are: (1) regional analysis, (1) form - notches or sombreros; (2) line - which establishes broad visual quality guide- haul roads; (3) color - bare against lines for implementation of basic land-use green vegetation; and (4) texture - excavated planning; and (2) site-specific analysis, overburden. which establishes specific visual resource objectives for the site, which may be as Surface mining's visual impacts result large as several thousand acres. Generally, from basic mining activities and other asso- the site-specific analysis of the four cate- ciated environmental impacts both on-site gories of stages of mining, as previously and off-site. discussed, are evaluated, and design changes are proposed if required. Simulation and

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computer-graphics are a key to complete SURFACE MINING CONTROL AND understanding by all. Let's look at a RECLAMATION ACT OF 1977 case study for illustration. Public concern over the environmental, cultural, visual, and economic impacts of Case Study 1 surface culminated with the enactment of the Surface Mining Control and This case study involves a large lime- Reclamation Act of 1977. In the law, stone deposit in . At the time of Congress recognized that recovery of coal this proposal, there was no specific mining through surface mining methods must continue plan, but the proposal indicated these visual in order to meet future national energy impacts were possibilities: needs, and they established standards to insure that it would be conducted in a sound 1. Large open-pit mine; manner.

2. Slurry line to deep water port; In various sections, the Act requires consideration of the visual environment 3. Power and telephone, water lines, through explicit language and general legis- material and housing center. lative intent. In addition, environmental standards set by the law do much to alleviate The visual analysis process included the visual impacts associated with surface the following computer-generated overlays coal mining. Beyond these standards, the for analysis of impacts on the visual resource: final regulations, which translated the law into detailed procedures for implementation, 1. Seen areas from 36 observation points; only minimally express visual criteria.

2. Seen area during exploration; Visual considerations are included in the final regulations in two categories: 3. Slope map and aspect maps and (1) regulation of present mining practices; vegetation; and (2) reclamation of previously disturbed mine lands. 4. Visual Resource Management class maps; Many people believe that in large part 5. Overlay to indicate degree of visual the back-to-contour reclamation provision for absorption capability of proposed new mining was adopted in response to public action. concern for the visual impacts of surface coal mining. As such, additional visual With these base overlays, the agency now criteria are not required in order to grant can evaluate a definite mining proposal, in- mining permits on private lands unless the cluding supporting facilities. Quality land has been designated unsuitable for standards to lessen the visual impacts now surface mining, nor will they be used to can be implemented by management. Specific determine variances for post mining land design alternatives are now identified and uses. Each state has the discretion to implemented. include or omit visual criteria as part of the designation criteria within their Lands One federal agency utilizes a design Unsuitable for Surface Mining Program (LUSM) process called a "visual contrast rating and to determine reclamation priorities process" to insure that all design alterna- within their Land Reclamation tives are carefully and analytically con- Program (AMLR). sidered to meet the visual objectives for the site. It has been found to be a valuable Visual criteria will be considered for tool for planning and design implementation permitting surface mining on federal lands for mining plans, etc. Examples of these and to determine priorities within the USDA various "nuts and bolts technology" are dis- Soil Conservation Service's Rural Abandoned cussed in the subsection on Surface Mining Mine Program (RAMP). It's uncertain whether and Reclamation. visual considerations will have a role in setting priorities for distribution of research funds.

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SUMMARY Technology will allow the designer to show more clearly planning and design alter- With the increasing knowledge acquired natives to all constituents through computer- by study, practice, and experimentation, graphic systems and simulation techniques. surface mining is being developed into an art and science which is increasingly attrac- New equipment advances and other techno- ting trained professionals of all disciplines. logical advances will allow us to accomplish As a result, their impacts are being more in the future what today we think is unattain- effectively utilized in both private corpora- able. tions and public policy. This trend will increase. The key is a spirit, a belief, a commit- ment, that we must relate man to earth--for The individuals will have a significant ourselves and for future generations. We role in the enactment and enforcement have the creativity, the drive, and almost (monitoring) of existing and future surface the technology. We need communications mining laws and regulations. This will be among all, and time to enact these beliefs. especially true for local situations. The future role of visual resource Interdisciplinary team involvement, management in the eyes of the public will representing the physical/natural, social/ significantly increase. This concept will economic, and environmental design arts is be fostered by all, in recognition that pro- the key to the full enactment of surface fessional planning and design for surface mining in this country. mining is essential for economic, social, and environmental survival and enhancement for the lands of our country.

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