Wednesday, January 1, 2014

Maine's Pinatubo: Unearthing a Natural Disaster

Soon J.D. Irving Limited may be freed to start thinking about how to take 22 million tons of copper ore out of the ground in northern Maine. The Maine legislature may relax laws regulating the mining of metals in Aroostook County. While Irving consider strategies for extracting copper and zinc, as well as relatively small amounts of gold and silver, I have been thinking about how the metal rich rock, called sulfide ore, got there in the first place. It all occurred about 500 million years ago when a series of islands, not too unlike the Philippine islands, were forming off the coast of North America.

The best lens from which to consider what went into creating the ancient ore might be to consider a more recent event. Twenty-one years previous to the bill being passed, Mount Pinatubo was cooling off after a long summer of letting off steam. In the summer of 1991, the Philippine Sea Plate subducted beneath the Eurasian plate, releasing 10 billion tons of magma in a volcanic eruption. As the magma neared the surface, it released chemicals that refused to join with others to form minerals. Valuable metals, like zinc and copper and dangerous ones like cadmium and lead, were distributed as ash across the Philippine region. Far from a rain of wealth, the ashfall is thought to have significantly shortened human lifespan on nearby islands. Sulfur combined with oxygen in the atmosphere to form sulfur dioxide gas, which in turn joined with moisture in the atmosphere to form sulfuric acid. Aircraft throughout the Northern Hemisphere experienced corrosion damage from the acid for years afterward. It is with good reason that the eruption of Mount Pinatubo was regarded as a natural disaster.

Five hundred million years ago no one was around to experience the ash or acidity of eruptions that formed the islands that would become the metal-rich rock in northern Maine. The islands and the ore formed as two oceanic plates in a proto-Atlantic ocean collided. One plunged beneath, bringing loads of ocean water with it. As the water and the rock descended, both heated. The water would have rushed through subterranean rock, dissolving unmatched elements along the way. The scalding liquid would have picked up sulfur, then metals. It would wend its way upward, cooling as it went. As its temperature dropped the dissolved sulfur, submerged and lacking its partner oxygen, would seek out other mates, finding them in the unmatched metals that flowed alongside. The sulfur/ metal pairs, sulfides, solidified and were stored underground preventing life's exposure to corrosive acids or dangerous metals.

In the next decade J.D. Irving may decide it is worth unearthing the metal-bearing sulfides of Aroostook County. But the price of digging up a natural disaster must be paid. Payment can be rendered in advance if the mining company works to prevent the spread of sulfur and metals into the environment. It can be paid after the fact by the citizens of Maine, in the form of clean up costs. Or, it can be paid by sacrificing the beauty and balance of northern Maine's natural ecosystem. Regardless, the cost must be rendered, and it's best to consider this before the bill comes due.

Beck, Fredrick. "A History of Non-Ferrous Metal Mining and Exploration in Maine." Geological Society of Maine. N.p., n.d. Web. 1 Jan. 2014. <http://www.gsmmaine.org/wp-content/uploads/2010/02/Beck-A-History-of-non-ferrous-metal-mining-and-exploration-in-Maine.pdf>.

Casadevall, Thomas J. , Perla J. Delos Reyes, and David J. Schneider. "The 1991 Pinatubo Eruptions and Their Effects on Aircraft Operations." Fire and Mud: Eruptions and Lahars of Mount Pinatubo. U.S. Geological Society, 10 June 1999. Web. 1 Jan. 2014. <http://pubs.usgs.gov/pinatubo/casa/>.
"Environmental Health and Safety Guidelines Base Metal Smelting and Refining." International Finance Corporation. International Finance Corporation, 30 Apr. 2007. Web. 1 Jan. 2014. <http://www.ifc.org/wps/wcm/connect/4365de0048855b9e8984db6a6515bb18/Final%2B-%2BSmelting%2Band%2BRefining.pdf?MOD=AJPERES&id=1323152449229>.

"Open-pit Metal Mining in Maine." Natural Resource Council of Maine. Natural Resource Council of Maine, n.d. Web. 1 Jan. 2014. <http://www.nrcm.org/issue_mining.asp>. 

"Volcanic Gases and Their Effects." Volcano Hazards Program. U.S. Geological Survey, n.d. Web. 1 Jan. 2014. <http://volcanoes.usgs.gov/hazards/gas>. 

"Volcano or Environmental Disaster?." VolcanoCafe. N.p., 18 Nov. 2013. Web. 1 Jan. 2014. <http://volcanocafe.wordpress.com/2013/11/18/volcano-or-environmental-disaster/>.


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