Metallic mining years away
Friday, August 29, 2014 10:19 AM
It will be a long time before anyone in Winneshiek County gets rich off metallic minerals under the ground.
That was the report from Dr. Ray Anderson, retired geologist, to the Winneshiek County Board of Supervisors Monday.
Anderson, who retired last year following a 43-year career with the Iowa Geological Survey, addressed the Board and more than 100 people in attendance following an invitation from the Board.
Supervisor Dean Thompson said the Board invited Anderson to speak following a tour Thompson, Planning and Zoning Chair Wendy Stevens and Darrel Branhagen, candidate for Iowa House District 55, took of the Pattison sand mine in Clayton County.
During the tour, Pattison staff provided the group with an Iowa Geological Survey press release that explained the potential for strategically important deposits of metallic minerals.
“With so little science-based information at hand – and no shortage of rumor and misinformation – citizens might react by checking their property’s mineral rights, studying the market price of platinum, buying backhoes, becoming unnecessarily agitated, or all of the above,” said Thompson during his introduction of Anderson Monday.
Last year, the U.S. Geological Survey (USGS), working with the geological surveys of Iowa and Minnesota, initiated a program to study the “basement complex” – rocks below sedimentary rocks or sedimentary basins – of Northeast Iowa and adjacent Minnesota.
The study was initiated due to the similarities between interpretations of the geology of the Northeast Iowa Plutonic Complex (NEIPC) and the Duluth Complex in Northeastern Minnesota.
These basement rocks, located around 2,000 feet below the land surface, are currently interpreted as a series of iron-rich intrusive rocks associated with the formation of the Midcontinent Rift System, a “failed rift” in the center of North America. It formed when the continent’s core began to split apart about 1.1 billion years ago. A failed rift is the result of continental rifting that failed to continue to the point of break-up. When the rift failed, it left behind thick layers of rock, which today are buried beneath sedimentary formations.
Recent industry exploration of the Duluth Complex has led to the discovery of platinum group elements (PGE) in those rocks, leading to the suggestion of similar mineralization in the Iowa rocks.
In late 2012 and early 2013, the USGS obtained high-resolution aerial gravity gradiometer, aeromagnetic and aerial electro-magnetic data using a low-altitude helicopter and fixed-wing aircraft platforms over part of Winneshiek County and adjacent areas of Fillmore and Houston counties in Minnesota.
A slow process
Anderson explained determining whether or not the area contains minerals the USGS would deem “strategic and crucial minerals” takes time.
He said one company has been working on the Duluth Complex for 15 years, and they are still probably five years out.
“I wouldn’t be digging up your backyard for rocks just yet,” said Anderson.
Anderson explained in preliminary studies, Duluth is estimated to have deposits worth $64 billion, which could include stores of copper, nickel, platinum, palladium, gold and more.
He said the USGS is tasked with finding domestic resources for these items, but it takes years and major funding to do so.
“We were planning to do it this year, but the USGS ran out of funding (for the project),” said Anderson, adding maybe the Iowa Geological Survey would chip in.
“We’ve put it on the calendar, but we haven’t come up with enough money. I think it would be really important to understanding what’s there,” he said.
Anderson said one step the USGS has talked about would be to work with the Skyline Quarry well north of town.
The well shaft currently goes down around 1,600 feet. Anderson said an additional 250 feet would lead them to the rocks in question.
“How far they would drill into that, depends on how much money they could come up with. I would like to see them go an additional 400 or 500 feet,” said Anderson.
When someone asked what degree of radioactivity might be present at 2,000 feet below the surface, he said “not anything that would be dangerous for workers down there. We’re not looking at that as a potential problem.”
One attendee asked if there is any way to assess the potential viability of the deposits from above ground.
Anderson said there is not.
When someone asked if the identified deposits mimic the Decorah crater, Anderson said the crater is not at the center of the deposits, but lies inside the area.
Another person asked if there are any rules which govern what happens next. Another asked how the process is proceeding in Duluth.
“Iowa doesn’t have much in the way of mining rules and regulations,” said Anderson, adding in the Duluth area, it has been a private company, which has purchased land for prospective mining.
“The USGS doesn’t want to get involved (in the mining),” he said.
When someone asked Anderson about mineral rights, he responded that generally speaking, Iowa landowners retain their mineral rights.
“You’d have to check with lawyers, but there are few exceptions to that,” he said.
Anderson said it would be up to the landowners as to whether or not they wanted to allow land exploration of their property.
“Chances are, if they wanted to explore, they would buy the mineral rights and you would get a percentage of it,” he said.
When John Klosterboer asked what type of toxins and environmental consequences could be associated with this type of mining, Anderson said he was “not a mining expert.
“I know they can use some pretty nasty things sometimes. Gold miners use mercury. They’re going to have to follow whatever the rules are locally. I can’t imagine they couldn’t work out some way to do it in a safe way,” said Anderson.
When Joann Hagen asked what the mine would actually look like, and if it would be an underground mine or if the ore would be extracted chemically, Anderson responded it would involve miners going down there and bringing out the ore.
When Stevens asked Anderson how he would proceed as a member of the Planning and Zoning Commission regarding possible safeguards, Anderson said, “I would just let it go. I would encourage the USGS to do everything they could and I would encourage exploration companies to come in.”
Anderson said, “If I was a citizen, I would be real interested in it. Do we really have valuable minerals or not? After that, you can decide whether you want to put up with the headaches associated with mining.”
Anderson added although “hundreds of billions of dollars is a lot of money to the economy … I’d say the chances are there will probably never be any mining going on around here, but who knows?”