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Penokee Range in Wisconsin. We

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¶ … Penokee Range in Wisconsin. We focus our analysis on various areas of the range such as its general geology, formation, surficial geology as well as quandary geology. The paper also focuses on discussions around the major issues surrounding the proposed building of an iron mine on the range. In this paper, we discuss how the mine will affect the geology of the range as well as the environmental impacts of building such a mine on the range.

The Penokee Range in Wisconsin is an important feature of the county. However, in the past few months, the region has been on the headlines as a result of the proposed building of a mine which is regarded as one of the ecological hotspots of the region. There has been a lot of foul cry from environmental agencies, house representatives and even locals on the environmental and social risks that the construction of iron mines on the range could cause. The company that wants to build the mine however claims that it enjoys the support of a "silent majority" of the residents in Ashland who it purports to be in supports of its proposal to construct an extensive iron mine in the Penokee Range (Bronam,2011). In this paper, we present an analysis of likely environmental impact of the proposed iron ore construction on the Gogebic-Penokee Range.

Formation of Gogebic-Penokee Range.

The formation of Gogebic-Penokee Range can be traced to the formation of the Precambrian-iron (James,1973). The Gogebic-Penokee Range was formed during the second phase of the Penokean Orogeny. Penokean Orogeny was a period of mountain building that took place in the early Proterozoic period (1.85-1.84) billion years ago in the North American region. This area is what is currently called Wisconsin, Minnesota, Ontario and Michigan. The Penokean Orogeny was a major even in North American continent formation. Prior to this event, the area was a continental margin (passive) that was occupied by a relatively shallow sea that created the large sediment deposits that includes the banded iron formations that form part of the Iron Ranges. The Penokean Orogeny took place in two distinct phases. The first phase involved the collision of an island arc known as Pembine-wausa terrane with a very ancient North American craton and this lead to the formation of the bar-arc basin. Parts of Wisconsin and Illinois were formed in the second phase which involved Marshfield terrane, a microcontinent (Holst,1989).

The geology

The Penokean orogen can best be described as an Early Proterozoic belt which is highly deformed. It trends towards south-west and Archean craton margin along the southern margin (Hoffman, 1988).The Penokean orogen is truncated by Grenville orogen to the east, Central Plains orogen to the southwest (Sims and Peterman, 1986).

The very early Penokean orogeny models for Minnesota revealed that intracratonic tectonism was the main mechanism involved in their formation (Morey and Sims, 1976). These models made a lot of emphasis on the role played by the basement rock that underwent a vertical remobilization as indicated in the work of Morey (1979). The same explanation is used for the formations in Upper Michigan. Cannon (1973) stressed the role of vertical movement of the basement rocks in the region's structural evolution. The last decade has however seen the emergence of a new theory that presents the idea of plate collisional movement as the main feature of the tectonic models for the Penokean orogeny for the Minnesota and the Upper Michigan regions (Van Schmus, 1976, Sims et al., 1987). The rock formation has several assemblages. The Wisconsin magmatic terranes are part of the southern assemblage and are primarily composed of volcanic as well as plutonic rocks. Several Geochemical analyses have indicated that these rocks have an affinity for the island arc (Sims et al., 1989, Shulz et al., 1984, Schulz, 1983).

Figure 1: A map which shows the distribution of all sorts of lithologies in the Metasedimentary and Middle Precambrian rocks that includes iron-formations, slates, conglomerates as well as carbonates. The rocks are least deformed as well as metamorphosed in regions towards the extreme direction of northwest. The rocks contain kyanite as well as other forms of minerals of metamorphic grade to the South. The metavolcanic rocks are made up of felsic and mafic lavas as well as other epiclastic and pyroclastic materials. The granitic rocks are made up of granitic plutons, post-tectonic granites (alkali-rich) and epizonal granodiorite (Ostrom,1979, p.4).

Figure 2: A schematic cross-section indicating the lithologic-structural features that occurred during the Middle Precambrian age "Penokean" event. Wisconsin is located near the Wausau (left side) at the Middle Precambrian period which took place close to 1,900 million years ago (Ostrom,1979, p.4). To the north is the platform which contains sediments like iron-formation as well as carbonate deposits.

A summary of site description

Martin (2008,p.1916) pointed out that the area is made up of a geologic feature that is referred to as Penokee range. The topography is rugged and was formed several million years ago. Since then, the area has weathered as well as eroded in order to form its current configuration. The area features three hundred and twenty foot rise in elevation. The rock that underlies the Range is very resistant with a total of 4 glacial events failing to completely pulverize it. There are two rivers, Montreal and Potato that effectively breaks through the range in order to foam very spectacular classic water gaps in this section (Martin,2008,p.357). To the southern part of the Penokee range is located Alder Creek which runs slowly, parallel to the topography of the range. The area has resistant shale, swamp conifer vegetation and alders. The bedrock has forests vegetation on it which is covered by aspen, yellow birch, maple as well as basswood. Patches of other vegetations also exists.

Issue of conservation

The areas having steep topography have in the past not been extensively The whole range had been a subject of deep-hole mining activities which ended sometime in the 1960s. This left the area relatively undisturbed. What remained are the areas that are extensively forested and are mature in regard to the growth of vegetation. Various forms of developments on the forested range coupled with various types of forest-harvesting activities, over-browsing by the local deer population as well as invasive species have degraded the habits extensively. This has also lead to a simplification of the forest structure. This led the Iron County Forestry to recognize the Penokee Range as an area for birds by setting up close to 1,700 acres of the County Forest to be used as biological reserve. The area was appropriately named the Penokee Biological Reserve.

The proposed construction of a mine on the Penokee Range

Several companies have expressed a lot of interest in constructing mines for extracting the iron ore from the iron-rich Penokee-Gogebic Range, an area that extends about twenty five miles through the Ashland and Iron Counties in northern Wisconsin (The Nature Conservancy,2011).

A large part of the Range belongs to RGGS Land and Minerals, Ltd. A company headquartered in Houston, Texas together with LaPointe Mining Co. from Minnesota. Both companies control close to 22,000 acre and twelve mile narrow stretch of the larger Penokee Range, apportion that lies southwest of a region called Hurley and close to 6-miles to the west of Mellen. Also another group of companies called the Cline Group from Florida has managed to secure an option to allow them obtain mineral rights that are held for the property. It has since gone ahead to create a subsidiary named Gogebic Taconite (G-TAC) to proceed with the mining of iron ore.

It is noted that any decision that is made to allow the extensive mining of iron as well as other minerals in the region should take a lot of considerations of the forest, water as well as other forms of natural resources that makes an important component of the region's economy and livelihood. The certification of mining activities in the area would disrupt the environmental and social equilibrium of the region since it would most likely cause a destruction of forest, loss of wildlife and hence a disruption of the tourism economies, loss of culture as well as a contamination of the currently clean and safe water sypply.The result would be disease and death for animals, humans and plants that depends on the current biodiversity.

Taconite iron ore and its source

The iron to be mined from the Gogebic-Penokee Range is called taconite iron ore which is a low-grade and magnetic iron ore. At the time when the high grade iron ire was still available in large quantities, taconite iron ore was considered a low grade iron and waster rock which was never extracted or used. However, as the supply of the high-grade iron ore dwindled, the iron ore mining industry began to realize that their only hope was taconite. They regarded it as an important resource. They therefore took their time and effort to develop a process for creating taconite pellets through the concentration of the low grade iron ore into a resource which is economically viable. Since taconite iron ore can be attracted by magnets, it is called a magnetite. Magnetite is abundant in the Minnesota Iron Range as well as the Michigan Iron Range that is located next to Marquette as well as in the Penokee Range in Wisconsin, Minnesota. In Wisconsin-Minnesota's Gogebic-Penokee Range, the taconite iron ore deposits are concentrated on the bands that run from the Mellen area in Ashland County up to the area near Upson in the Iron County.

The taconite iron ore extraction process

The mining of taconite iron ore in the Gogebic-Penokee Range is carried out by means of open-pit mining methods. The mining process commences by the drilling of a hole into the ground in order to determine the exact location and quality of the iron ore deposit. The drilling also reveals the characteristics of the rocks that surround the ore. For the rather large modern mines, there is a need to carry out several exploratory as well as characterization drilling of bore holes into the iron formations. After the adequate characterization of the iron ore body as well as the one for the overburden has been characterized, the next process involves the removal of the non-ferrous rock that lies over and next to the iron deposit. The ratio of the iron ore to the waste rock that has to be removed in order to access the iron ore (striping ratio) of 2:1 or 1:1 is common. If the iron ore deposit has vertical orientation to the ground surface, then the amount of overburden that has to be removed in order to access the iron ore may be greater that the amount of the iron ore to be extracted. The rock that surrounds the iron ore area/zone is then hauled out of the open pit mine and then stored appropriately as waste rock. In order to remove the iron ore, the rock is blasted with dynamite explosive and then loaded onto trucks. They are then removed from the pit area. The ore is then transported to the processing plan a place where it would be crushed using a series of crushers as well as mills. The scale of land alteration that is associated with the mining activities for the extraction of taconite are enormous. The open pi mines would create permanent alterations to the landscape. The resources and the habitats that the Gogebic-Penokee Range supports would also be removed permanently.

What makes the Penokee Range special?

The Penokee-Gogebic Range is made up of two large and steep ridges that lie parale to each other. These two ridges dominate the local landscape and rise to about 1200 feet above Lake Superior which is located nearby. The soil condition and the region's topography results in a diverse habitat that supports a large number of natural communities and species.

Water

Water is one of the resources that are at risk of being polluted or depleted by the proposal to start extensive mining at the Penokee-Gogebic Range. Close to 71 miles of rivers and intermittent streams have been noted by the Nature Conservancy (2011), to flow through the area that has been ear-marked for the proposed mining activity. These rivers and streams currently empty their water into Lake Superior and Bad River. The surface as well as the ground water that originates from the Penokee Range is noted as one of the main sources of waters that are used in the Upson, Marengo, Udanah, Ashland, Highbridge as well as Mellen municipalities.

A large part of the various waterways that include Potato, Bad as well as Tyler Folks rivers are given the Exceptional or Outstanding Resource Waters designation to mean that they are Wisconsin's rivers of highest quality. The good quality water makes them favorable for fishing and wildlife rearing.

Wetlands

It is worth noting that the proposed area of mining embodies a large part of the headwaters that are part of the Bad River watershed. This supports close to sixteen thousand acres of the Kakagon-Bad River Sloughs. These are known as the largest watershed complex that is underdeveloped in the upper Greater Lakes region.

The sloughs in the wetlands have a very strong cultural significance to the natives of the area. They also support the Great lake basin's largest natural wild rice bed. That has been used for several centuries. The streams as well as sloughs that feed the entire wetland system comprising of Kakagon river, Bad river as well as Wood and Bear Trap creeks are all directly dependent on the ground and surface water that emanates from the Penokee Rage. The Sloughs are also noted to be perfect natural homes to several endangered and threatened species like bald eagle, trumpeter swam, piping plover as well as lady-slipper orchid.

The forest

Since the proposed mining area covers close to thirty five square miles of the northern hardwood forest, the current forest is at risk of being destroyed despite the fact that it has been used for the production of hardwood for several decades

A large part of the land is protected by the Wisconsin's Managed Forest Law which makes it open for the recreation of the general public. Activities such as hiking, hunting as well as snowmobiling can be carried out here. The forest in this region acts as a link between the Ottawa National Forest located in the Upper Peninsula of Michigan and the Chequamegon-Nicolet National Forest that is located ion in northern Wisconsin. This means that it provides close to forty miles of an expansive continuous forest cover that supports the lives of several animals such as timer wolves. The forest also acts as the breeding grounds for a large population of birds that are noted to be migratory.

A detailed analysis of the effect of Iron ore mining on the Penokee-Gogebic Range

A review of literature clearly indicates that the concept of iron ore mining has devastating effects on the surrounding environment in regard to pollution and general damage (Ratha and Venkataraman,1995).The recent discovery of the Penokee-Gogebic Range by the U.S. Geological Survey (USGS) as a potential source of a large copper as well as nickel deposit makes it the concept of iron ore mining in the region environmentally detrimental. This is because the two heavy metals, copper and nickel would automatically be produced as the by-products and thus pose environmental risks associated with the mining of metallic sulfides (Clements and Sack,2008).

The mining of metals in the Penokee-Gogebic Range have been noted to pose a significant amount of environmental threat to the surrounding communities who depend on the area as their source of sustenance. Other than the extensive aesthetic impact that it might have on the landscape, the trees that are currently intact would become very fragmented and the increased runoff as well as the potential level of acid and heavy metal contamination that might emanate from the tailing pile may drastically change the health of the existing river systems. The heavy machinery that is to be used as well as the industry to be constructed on the land may produce too much hydrocarbon emission as well as ore dust that may deteriorate the air quality while contributing to anthropogenic global climate change.

Since the area is the headwaters of rivers such as Bad River, a river which is regarded as the largest watershed in Wisconsin and which also drains into Lake Superior, the seventy two rare species as well as endangered plants and animals that reside in the Bad River may perish as noted by the Nature Conservancy.

The changing water levels as well as the pollutants that may get their way into the water may have a great impact on the Wild Rice beds that grow at the mouth of the river. The Mahnoomin region is of great economic value as well as source of livelihood of the Ojibwe people. Additionally, the tourism-based economies of the communities that live in lakeside regions like Washburn, Ashland and Bayfield could be negatively impacted by the contaminants from the mining activity which could easily find their way into Lake Superior. Even though the mining executives have attempted to convince the people that they are sensitive to their concerns of the environmental impact of the mining activities by claiming that they would rely on technologies that would reduce the level of pollution. Most residents and experts still worry that the overall image of the paradise of North Wood would forever be altered by the creation of large open-pit mines. It is noted by Clements and Sack (2008) that even the very best of technologies, the environmental consequences may well outweigh the perceived short-term economic benefits that may be derived from the creation of the mines.

Figure 3: A diagrammatic representation of Gogebic section at the Penokee-Gogebic Range (Marsden,1978)

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PaperDue. (2011). Penokee Range in Wisconsin. We. PaperDue. https://www.paperdue.com/essay/penokee-range-in-wisconsin-we-47956

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