Volume 11 | Issue 4 | Year 2008

Here’s something to mull on: there were no golf courses in Permian North America, roughly around the area of Idaho, 240 million years ago. A ludicrous statement? Yes … and no. Certainly, if any club-wielding took place, it wasn’t to hit small balls down a fairway. But if you’re charged with reclaiming a mining operation, whose geological layers were laid during the Permian Age, you’re sensitive to the fact that the landscape whose earth you’ve moved never consisted of neatly mowed, rolling green contours – not 240 million years ago, not 30 years ago – and shouldn’t now.
That is to say that Monsanto, as it restores land to its pre-mining state, is as attentive to the landscape – terrain, treelines, habitats, sandhill cranes and all – as it is to its phosphate mining operation, which produces elemental phosphorous, a key ingredient in the company’s Roundup® herbicide, a top-selling product for Monsanto. And paying attention to environmental habitats is one of the reasons why Monsanto has won accolades such Habitat of the Year Nominee from the Wildlife Habitat Council.

Monsanto’s phosphate mining in the region dates to 1951, but the discovery of deposits there extend back to the 1920s, relates Dave Farnsworth, manager of mineral operations. Mining rights in this area fell under government jurisdiction in the 1920s, whereupon the government sponsored an intensive exploration program, sending geologists throughout Idaho and Utah. “A lot of the work we do now is because of their work in mapping out deposits,” Farnsworth says.

Monsanto, which calls itself an “agricultural company,” actually had been mining phosphate since the 1930s in the Tennessee area, and as the nation came out of World War II, there arose additional demand for phosphate detergent, and other phosphate products, which drew Monsanto’s attention westward. From 1951 the company has mined four sites, beginning with the mine known as Ballard, until 1969; the Henry mine from 1969-1989, and Enoch Valley from 1989-2004. The current mine site, South Rasmussen, has been mined since 2001. The company also maintains a processing plant in Soda Springs, Idaho.

Monsanto, Farnsworth says, holds about 20 different mining leases, and produces from the current mine about 1.1 million tons of ore a year. Such productivity necessitates the removal of about six to seven million tons of overburden material – dirt and rock – that doesn’t contain phosphate content.

“What you have are two ore layers or beds,” Farnsworth explains. “One is 45 feet thick and the other is 25 feet thick. Other material needing to be moved consists of limestone, chert and shales.” The ore is processed into elemental , or raw, phosphorous. “Phosphate ore is 10-15 percent phosphorus and we refine that into a product that is 99.9 percent pure phosphorus.” This ingredient goes into various products such as toothpaste; it makes the fizz in soda pop (phosphoric acid); plasticizers (phone cords) and also tires. But over 70 percent of the product goes into Roundup®, which kills invasive plants and noxious weeds.

“We run the mine in two 10-hour shifts a day, 12 months out of the year, even in the winter, when there’s three to four feet of snow on the ground and temperatures hover around minus 30 degrees,” Farnsworth says.

Because of consolidation, Monsanto’s plant is the last one of its kind operating in the Western Hemisphere. Ore comes in and is heated in a kiln, which is a long tube, 16 ½ feet in diameter and 325 feet long, and lined with bricks. The near-melting of the ore drives off organic compounds, the hot gases of which go through scrubbers to clean out particulates from the air. The remaining material is converted into a nodule. “It looks like basalt rock, full of little holes,” Farnsworth says. That nodule is sent to the furnaces, combined with coke, which contains carbon and silica, and heated to over 6,000 degrees – “We use the same amount of electricity as residential demand in Kansas City, Mo.” – and eventually comes out as elemental phosphorus gas. This cools and is run through a sprayer, condenses and forms a liquid. However, there’s a need for caution with phosphorus in this form, as Farnsworth explains: “Elemental phosphorus will ignite violently as soon as it gets near oxygen. It has to be handled under water with a blanket of nitrogen gas at the surface.”

Altogether, the plant produces more than 200 million pounds of elemental phosphate a year, which leaves the plant via railroad in specially designed cars and tanks.

Altogether, the mining site occupies close to 300 acres and through reclamation, Monsanto tries to keep the mining footprint as small as possible and reclaim as close behind mining as practical.

“What makes us unique is that we go above the law with reclamation and the law is pretty strict on requirements. Nothing in the law requires trees, but we plant 5,000 trees a year. We’re also proactive in mimicking original land forms. We move 50,000 tons of rock a day and because of that, we change the look of the land. We’ve put in an effort to contour sites to look like they did before we started the mine. We don’t want the land to look like a golf course.”

Indeed, adds Chris Leatherman, mine manager, “We take a lot of pride in our stewardship. We do a lot of reclamation with conventional farm equipment to flatten and contour the land. We would hope 20 years from now that someone wouldn’t even realize there’s been a mine here. One of our backfill designs entails putting overburden back into the area to create hills and valleys to blend in.”

He adds that Monsanto works with a company called Degerstrom Ventures, Idaho-based contract mining specialists, on environmental compliance issues. “We have someone who spends a lot of time identifying the ore and delineating it from the waste.” He continues: “The ore was formed in an ocean environment during the Permian Age – that’s when most of this phosphate was laid down. There was a great inland sea and it was a very warm and humid environment.” After the ocean retreated back, it took the next several million years of land change and reformation to deposit and bend the phosphate layers.

A perennial concern with such reclamation efforts is selenium, which is toxic in large amounts, but trace amounts of it are necessary for cellular function in most, if not all, animals. Geologists, Farnsworth says, have known about its presence in the ground for years but were not aware that it was leaching from the rocks as these were moved.

“Leaching has occurred since the deposits formed a million years ago but in a slower manner,” Farnsworth points out. “Because we stirred up the pot we accelerated the process. The last few years we’ve been involved in innovative techniques to control and measure potential impact” on the environment.

Reclamation Specialist Mike Vice notes that Monsanto collects vegetation samples of reclaimed areas in their first, second and fifth years of reclamation to analyze for selenium. “We used to be able to use brown shales for planting medium if we didn’t have enough topsoil. In 1999, we initiated better use of topsoil starting at Enoch Valley, using limestone, shale, and chert. On the overburden we put a five to 10 foot limestone cap and then two feet of topsoil on top of that – that way the deep rooted plants can’t get down into the selenium-bearing material.”

Among other remedies is the construction of settling ponds to control water and snow runoff, which occurs mostly in April and May. And because areas that naturally collect water turn dry by mid-July, the ponds also serve as a vital water source for animals and birds.

Other innovations include a shingle system for selenium on the overburden piles to stop or hinder the leaching progress. Much like roof shingles, these keep the rain out of the overburden, and thus, keep the selenium out of water runoff. Geologists are also able to locate the selenium deposits in the overburden so that these sections can be properly sealed and protected.

Leatherman notes that additional environmental measures entail controlling airborne particles and dust. “It’s a 3 ½- to four-mile haul from mine to load out area and there are air compliance requirements. We water the road and in springtime put down chloride to minimize dust.”

Vice adds that Monsanto’s voluntary work on behalf of the environment is “impressive.” We go above and beyond what is required in reclamation. We plant 15 and 19 species in the seed mix as opposed to the state’s requirement of eight. We go out of our way to plant trees and shrubs and we collect local tree seeds for growing out our own root stock. Great Bear Restoration in Montana receives the seeds and plants them. We’ve been doing this since 1993.”

Also a part of the reclamation process is the construction of wildlife habitats consisting of rock piles and brush piles for shelter. “That makes us unique – a lot of companies don’t do that,” Vice says.

Through all of these various activities, Monsanto keeps its environmental commitment high and its footprint small, so that future generations – wildlife and people – can enjoy a landscape the way it is supposed to look, and not permanently damaged. As Farnsworth adds, “Monsanto is very concerned about doing the right thing – not because it’s mandated but because it’s the right thing to do. Our goal is to make ours one of the best mining processes and operations in the world. It starts from the day we get the lease and stops only when the highest standards of reclamation are met. There isn’t a day in which environmental excellence isn’t paramount.”

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