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Mine dump at the Tintic Standard Mine near Eureka, Utah

Mine dump at the Tintic Standard Mine near Eureka, Utah

On Tuesday, March 12, 2013 I took three students down to Eureka, Utah to collect our third set of soil samples for our Amercian Chemical Society grant project. Jeffrey, Sean, and Indie helped to collect samples and measure the soil pHs, as well as explore the history of the Tintic Mining District.

Mine dump with contaminated soils at the Tintic Standard Mine

Mine dump with contaminated soils at the Tintic Standard Mine

This time our first stop was at the old Tintic Standard Mine workings above Burgen and Dividend in the East Tintic District. Of all the ore bodies in the area, these on the east side of the Tintic Mountains were the last discovered and the Tintic Standard Mine was in full production by the 1920s. A reduction mill was built across Goshen Valley at the warm springs near Genola. Workers lived in a company town below the mine called Dividend. The mine produced well into the early 1940s, when it was partly shut down for the war effort, then re-opened. Work continued sporadically into the early 1970s.

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Collar and shaft at the Tintic Standard Mine. Even with a chain link fence around the hole, the loose soil at the collar could cave in and makes this shaft a dangerous place if you get too close.

There are still quite a few artifacts and ruins at the site, and care must be taken as there is a large vertical shaft with loose dirt around the collar, so you should stay well back from it. There is a large glory hole on the back hill and two water tanks further up, with the remains of a wooden ditch that brought water down to the company buildings and change room. The main portal to the mine went back from the change room, where there is still an old stove to keep the miners warm. That portal has been sealed off.

Stove in the change room at the main portal of the Tintic Standard Mine. This portal was active off and on into the 1970s.

Stove in the change room at the main portal of the Tintic Standard Mine. This portal was active off and on into the 1970s.

After exploring around, we collected some samples from the mine dump at the bottom of the hill where melting snow had created a clayey puddle. We also collected several samples along a trench that had been cut into the waste rock dump, where the soil was discolored with purplish or yellow deposits. The pH indicator needle pegged several times, showing an acidic pH of less than 3.5. It will be interesting to see what kind of lead content these samples have.

Jeffrey and Indie taking samples at the Tintic Standard Mine

Jeffrey and Indie taking samples at the Tintic Standard Mine

We then drove into Eureka and scouted around town for some additional sample sites to collect on our final trip on Thursday, as well as to look around the mining museum, old City Hall building with its jail in back, and the cemetery. I showed the students how miners worked the air-driven hammers and how water was sprayed into the holes through the center of the drill steel. We looked at the skips or man cages, the water removal buckets, and the mucker machine out front. We walked around Main Street, which was very quiet for a Tuesday afternoon. Only a few cars were driving through.

David Black by City Hall on Main Street in Eureka, Utah.

David Black by City Hall on Main Street in Eureka, Utah.

Water chute, tanks, and old foundation at the Tintic Standard Mine

Water chute, tanks, and old foundation at the Tintic Standard Mine

We drove out through the west end of town on Highway 6 and took a detour through the cemetery, recording with the Flip cameras as we went.  We explored around the town of Mammoth and collected samples in a wash at the mouth of Mammoth Canyon. We then went on around to the Swansea mine dumps at Silver City to continue collecting samples.

Ruins of the old power plant in Eureka. Heavy machinery moving through town has contributed to the deterioration of historic buildings like this one.

Ruins of the old power plant in Eureka. Heavy machinery moving through town has contributed to the deterioration of historic buildings like this one.

Since last week, the snow has mostly melted and the ground dried out to where we could walk on it in most places without leaving muddy footprints. We sampled in several washes running off the main dump and in soils between the washes where some scrub brush survives. The main wash feeding off of the dump had several layers of brightly colored soils, ranging from reds to yellows to even a shade of green.

Mammoth Mine, headframe, and glory hole. This was the deepest mine in the district, with the richest concentration of silver and gold ore.

Mammoth Mine, headframe, and glory hole. This was the deepest mine in the district, with the richest concentration of silver and gold ore.

I can see we need to do more studying here, to see how much lead and acidic runoff continue down these washes into the valley beyond. The runoff water has left a red stain on the asphalt of the road over a hundred yards from the main dump. The soil on and near the dump itself and in the bottom of the washes is devoid of life. Even though the last time this mine waste was dug up was the 1980s, when the leach pile nearby was created, no plant life has yet to colonize the contaminated soils in about 30 years.

Sean and Indie at the Silver City mine dump.

Sean and Indie at the Silver City mine dump.

David Black taking pH readings in the middle wash draining the mine dump at Silver City.

David Black taking pH readings in the middle wash draining the mine dump at Silver City.

All told we had an enjoyable and low-key trip, and even though it was overcast the day was fairly warm. We had now collected all the samples we needed outside the remediated zone.

Contaminated soils in the wash draining the Silver City mine dump.

Contaminated soils in the wash draining the Silver City mine dump.

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Science Research Class at Walden School on our second collection trip.

Science Research Class at Walden School on our second collection trip.

After our fall semester, my research science class ended and the two sections of chemistry were consolidated down to one, with me teaching a computer technology course third period instead of chemistry. Without the two classes that could support the Tintic soil analysis project, I had to put the project on hold until I could get some more students involved. We also had an unusually cold January and February, with snow staying on the ground. This hampered our ability to collect samples. Between 3rd and 4th terms we hold a two-week Intersession at Walden School of Liberal Arts that allows us to teach specialty courses, and I dedicated my course entirely to finishing the Tintic project.

Altogether five students took the course, including Jeffery, Indi, Sean, Jem, and Aaron. To finish collecting all the samples, we had to take three additional trips down to the Eureka area. We were fortunate that the weather cooperated and warmed up enough that the snow melted.

Our second collection trip was on March 5 to the area of the Knight Smelter, the cyanide leeching pile, and Silver City. We stopped at the Bullion Beck Headframe on the way to take a group shot.

Ruins of the Knight Smelter built by Jessie Knight to process silver ore.

Ruins of the Knight Smelter built by Jessie Knight to process silver ore.

The Knight Smelter was built by silver tycoon Jesse Knight, who made his initial fortune with the Humbug Mine, then expanded along the Iron Blossom lode. Eventually, Uncle Jesse needed a smelter to concentrate and refine the ores from his mines, and he built it south of Eureka near the Union Pacific line. To connect his mines with the smelter and the Union Pacific main line, he built a narrow gauge railroad so that the smaller engines could make the turns and the steeper grades. A fairly level grade was built around the hills into his mines, and the road I walked on to the Iron Blossom #2 last fall followed this old grade. Jesse Knight contributed quite a bit of money to what was then the fledgling Brigham Young Academy, now Brigham Young University. The Jesse Knight Building, where I had several classes, is named after him.

Tank foundations and kiln at the Knight Smelter

Tank foundations and kiln at the Knight Smelter

The technology for refining ore went through rapid change in the 1920s. The smelter only operated for about four years, at which point it became cheaper to ship the ore by rail to the more modern smelters in Murray. The same thing happened with the Tintic Standard Mine and the reduction mill near Goshen.

There isn’t much left of the Knight Smelter except crumbling foundations for the solution tanks, a few archways where the kilns stood, and a pile of slag. Just to the south is the leeching pile. During the 1980s the price of gold jumped up when we went off the gold standard and the price was allowed to rise. Investing gurus such as Warren Buffet were advising people to invest in gold, and that drove up the price even more. Now, all these old tailings and waste rock piles that hadn’t been economical to process suddenly were. A layer of thick plastic was laid down and the waste rock crushed and piled onto the plastic, then a solution of cyanide was pumped over the pile. The cyanide would chelate with the gold and silver and trickle down through the pile into its lowest area, where it was pumped out and transported for smelting. This same process is being used at the Cripple Creek and Victor gold mine in Colorado.

Collecting a sample inside the kiln at Knight Smelter

Collecting a sample inside the kiln at Knight Smelter

We walked into the old smelter ruins and identified spots where there would likely be contamination, such as inside the kiln and underneath the tanks. We saw that a layer of sand was laid down under the tanks over the original soil, which is now covered with new soil deposited since the 1920s. We also collected samples from the top of the leeching pile. I picked up some samples of slag as well.

This smelter took the original ore and concentrated it by crushing and chemical action, using both physical and chemical separations. Mercury was used to bind to the silver (amalgamation). The amalgam was then heated up in a kiln to drive off the mercury and leave silver and gold. Since the silver started out in a compound with a higher oxidation state (+1) and was now a metal with an oxidation state of 0, this process is also called reduction. There were several reduction mills in the Tintic District. The leftover ore, after heating, still contained appreciable amounts of iron and lead, and was dumped onto a heap in a molten state. This waste material is called slag.

Slag at the Knight Smelter.

Slag at the Knight Smelter.

Sample under the tank foundations. Notice the layering of the soil; a layer of sand was laid down under the tanks when they were first built which is now covered with new topsoil.

Sample under the tank foundations. Notice the layering of the soil; a layer of sand was laid down under the tanks when they were first built which is now covered with new topsoil.

We moved on to the waste rock pile at Silver City where the Swansea Consolidated mine was located. Here, water runoff since the pile was created in the 1980s has washed small gullies fanning out south of the pile, crossing the road, and going on down the valley. The asphalt on the road is stained red with the iron sulfides. We collected on the pile itself, and used a portable pH meter to test the soil at locations on and near the pile. It was still too muddy to walk around much, and we were getting short on time, so we packed back up and drove back to Provo. We collected ten samples from five sites on this trip.

Testing the soil around the Swansea mine dump. The pH is very low, under 3.0.

Testing the soil around the Swansea mine dump. The pH is very low, under 3.0.

Sample at the Swansea Consolidated dump near Silver City

Sample at the Swansea Consolidated dump near Silver City

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