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Main waste rock dump at the Tintic Standard Mine.

Main waste rock dump at the Tintic Standard Mine.

In this post, we will report results and draw conclusions for our study of soil contamination in the Tintic Mining District. This study was supported by a grant from the American Chemical Society.

Students from Walden School of Liberal Arts brought back 42 samples of soils from the area in and around Eureka, Utah. Our purpose was to test for heavy metal contamination, especially lead. Previous tests done by the Utah Department of Health and the EPA showed lead contamination to be widespread throughout the town, due to the presence of historic concentration plants in the town and the use of mine waste rock as fill in many lots. Since there are mine dumps on the hillsides south of town, rain runoff also brought lead contamination into the residential areas.

Western side of the Swansea Consolidated mine dump near SIlver City.

Western side of the Swansea Consolidated mine dump near SIlver City.

These tests led the EPA to declare the town a Superfund project and spend $26 million to replace soils in some areas of town (but not all). They also placed limestone riprap over the mine dumps to prevent further runoff. The process took ten years and completely changed the look of the town, damaging or destroying several historic landmarks along the way, such as the headframes for the Eureka Hill and Gemini mines. Two landmarks, the Bullion Beck headframe and the Shea building, were restored. The rest have been left in ruins.

Middle section of the Swansea Consolidated mine dump near Silver City.

Middle section of the Swansea Consolidated mine dump near Silver City.

All of the tests we conducted were put into numerical form and entered into a spreadsheet so that we could compare the results. We used an ALTA II reflectance spectrometer to measure reflected light at eleven wavelengths, including four infrared wavelengths. We also tested the pH of the samples using several methods, including universal test strips, a garden soil test kit, and a pH meter. We tested for lead using a sodium rhodizonate solution, which changes from orange-red to pink in the presence of lead in neutral soils and to green or blue in the presence of lead in acidic soils. Please see our previous post for details on these tests. Since the rhodizonate test was qualitative, we assigned numbers depending on the color of the final solution so that some comparison could be made.

For the samples, we selected ten areas inside the town of Eureka, including some where the soil has been replaced and others where the soil is original. We tried to pick areas that were representative of the town as a whole. At each site, we sampled the surface soil and soil about six inches below the surface. We also sampled 12 sites outside of town, including areas away from town as controls and areas on or near exposed mine dumps, such as those from the Tintic Standard, Swansea Consolidated, and Tesora mines. We also took samples from gullies or washes downstream from mining areas and dumps, and from an exposed ore body (which has not been mined or processed) at a road cut along U.S. Highway 6.

Test Results:

Chart 1: Comparing Different pH Tests of Soil Samples. The readings taken with our portable pH meter provide the most consistent results (and can be done easiest in the field).

Chart 1: Comparing Different pH Tests of Soil Samples. The readings taken with our portable pH meter provide the most consistent results (and can be done easiest in the field).

As you can see from Chart 1 shown here, of the different methods we used to determine the soil pH, the pH meter was the most sensitive and consistently accurate. It was also easiest to use. It showed that most of the samples, were slightly acidic (between 6 and 7), but the samples taken from mine dumps and the areas immediately downstream were extremely acidic; in fact, some samples had a pH too low for our meter to read, which had a low limit of 2.5. Although not shown on this chart, the samples taken inside Eureka on our fourth collection trip all showed pHs near neutral (6 – 7).

Our lead test showed no discernable lead inside Eureka, even in soils that had not been replaced by the EPA. This is probably because our test is not sensitive enough for low lead levels. It becomes hard to distinguish the original color of the rhodizonate from the natural color of the soil unless there is enough lead present to create an obvious color change. In Chart 2, low levels of lead correspond very well with neutral pH soils.

Chart 2: Comparing Soil pH with Lead Levels. The lower the pH (more acidic) the soil samples were, the more lead was present with a correlation coefficient of rho = -0.876.

Chart 2: Comparing Soil pH with Lead Levels. The lower the pH (more acidic) the soil samples were, the more lead was present with a correlation coefficient of rho = -0.876.

The most interesting result of our study was to compare pH with lead levels. Chart 2 shows that the highest lead levels were found on or immediately downstream from mine dumps, which correlated very well with low pH levels with a correlation coefficient of rho = -0.876. Mine dump soils had high lead content and were highly acidic. Of course, this doesn’t imply causality: the high acid doesn’t cause lead, and the high lead probably doesn’t cause the acidity, but if one is present, so is the other.

Chart 3: Comparing Soils at Mine Dumps with Healthy Soil Using the ALTA II Reflectance Spectrometer. Healthier  soils were darker and richer in humus, whereas mine dump soils were pale and yellowish.

Chart 3: Comparing Soils at Mine Dumps with Healthy Soil Using the ALTA II Reflectance Spectrometer. Healthier
soils were darker and richer in humus, whereas mine dump soils were pale and yellowish.

In Chart 3, the reflectance spectrometer tests were inconclusive as far as detecting a signature for lead. We compared the results shown with samples of pure lead, pure galena (lead sulfide), and silver-lead ore. There were no obvious wavelengths that gave a definitive fingerprint for only lead.

The one useful result of the spectrometer tests was to confirm the overall health of the soil samples; those with lower percent reflectance overall were darker, richer, more healthy soils with more plant life growing. The lighter soils had less plant life and higher overall reflectances. The soils at mine dumps were yellowish to light purplish due to the presence of sulfur compounds, and these also had no plant life, lower pH, and higher lead.

Chart 4: Comparing the Levels of Nitrogen, Phosphorus, and Potassium in Soil Samples. The nitrogen and phosphorus tests gave no predictable results, whereas the potassium test showed higher levels of potassium in mine dump soils with high lead content (rho = .687).

Chart 4: Comparing the Levels of Nitrogen, Phosphorus, and Potassium in Soil Samples. The nitrogen and phosphorus tests gave no predictable results, whereas the potassium test showed higher levels of potassium in mine dump soils with high lead content (rho = .687).

Chart 4 shows the tests we conducted on soil nutrients. The nitrogen and phosphorus tests were inconclusive, and are probably due to the poor quality of the garden test kit we used. The potash (potassium) test did show higher potassium in the mine dump soils where lead levels were also highest, although the correlation was only moderate (rho = 0.687).

Conclusions:

A visual inspection of the mine dumps outside of Eureka, Utah in the Tintic Mining District shows that the waste rock and soils are highly contaminated. No plants grow on the dumps or in the gullies immediately below them. They are stained a bright yellowish-orange, and soils in the nearby gullies have layers of red, yellow, and even green. Overall, they are lighter and less rich than nearby soils with plant life. Our tests show that these mine dump soils are acidic and have high levels of lead contamination.

Similar mine dumps were located at the west end of town (around the Gemini and Bullion Beck headframes) and south of town (Chief Consolidated and Eagle and Bluebell mines). If the same pattern of contamination occurred there as what we found in the Swansea, Tesora, and Tintic Standard dumps, then it is likely that the soils downstream in the residential areas of town were also contaminated by lead and sulfur compounds. We did not find evidence of this in our tests of original soils inside town, but our test was not sensitive enough to find the lowest levels of lead. Soil pH throughout the town was slightly acidic, which may indicate sulfur or even lead content. We were not able to get the data from the original EPA tests.

Soil discoloration in the wash west of the main Swansea mine dump at Silver City.

Soil discoloration in the wash west of the main Swansea mine dump at Silver City.

Both pH and potassium content appear to be well correlated with lead content, with pH having a particularly high negative correlation (-0.876). Perhaps pH can be used as a marker, since it is easily measured. Where lead is suspected, a pH reading showing high acidity would indicate a strong possibility of lead. It would be interesting to see if the two measurements decouple as one travels further downstream from the mine dumps along washes and gullies. Do the lead and the acid travel the same distances?

Soil layers showing different types of contamination, in the middle wash downstream from the Swansea mine dump.

Soil layers showing different types of contamination, in the middle wash downstream from the Swansea mine dump.

Much remains to be tested. We have some additional grant funds that we will use to send four samples to an outside lab for detailed element analysis. I also hope to take all our samples to a local university and use an X-ray Fluorescence Spectrometer or Raman Spectrometer to get an accurate and precise readout of the lead levels and other heavy metal content. We need to determine the amount of sulfur compounds in the soils, and how that correlates with pH. We also need to pass our samples through a soil sieve and measure the relative sizes of particles and the amount of humus in each. We should test the mine dump soils to see if plants will grow in them compared to the other samples. Finally, we need to return to the site and collect more samples of other mine dumps, as well as the soils around and downstream from the dumps we’ve already tested. We need to determine how far the lead contamination and acidity travel down the washes and gullies and the extent to which the slope of the land affects this.

As with any field research study, it’s hard to keep all the variables constant. We’ve been careful and consistent with our tests, recording each location and using controlled testing conditions in the lab. But there are factors we can’t control. It could be that the low plant life on the dumps is simply because this is a desert, and plant life takes time to get established after soils are disturbed. The dumps were all dug up and the best materials were transferred to a leaching pile nearby in the 1980s. 30 years is not enough time for climax vegetation of sagebrush and juniper trees, but is enough time for grasses and low brush to grow. In general, soils in the area are poor in nutrients except where higher levels of water (such as in washes or gullies) allow more plants to grow and decay into better humus.

Staining on the asphalt where water draining off of the Swansea mine dump runs over the road near Silver City.

Staining on the asphalt where water draining off of the Swansea mine dump runs over the road near Silver City.

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Old car behind the Tintic Mining Museum in Eureka, Utah.

Old car behind the Tintic Mining Museum in Eureka, Utah.

During our Intersession period between third and fourth terms, I taught a class that would help complete our study of lead contamination in the Tintic Mining District around Eureka, Utah for our American Chemical Society Hach grant. We had already visited the area three times to collect samples in the various mine dumps around the area, but we needed one more trip to collect samples from inside the town of Eureka itself. We traveled down for this last trip on Thursday, March 14, 2013. I had three students with me from Walden School: Jeffrey, Indie, and Aaron.

Aaron, Jeffrey, and Indie collecting samples of a hydrothermal vein at a road cut on Highway 6.

Aaron, Jeffrey, and Indie collecting samples of a hydrothermal vein at a road cut on Highway 6.

We had scoped out the town and decided to collect at ten locations in the town and at least one location further southwest outside the entire district as controls. The town was cleaned up by the EPA as a superfund project, and $26 million was spent to dig up contaminated topsoil in sensitive areas, such as playgrounds, the baseball field, and lawns at the high school. Other areas have been covered with limestone fragments, or rip-rap, dug up at a quarry about five miles outside town and supposedly beyond the contaminated zone. Still other areas in town have had plastic netting laid over the ground, supposedly to prevent erosion from washing contamination back into the town. And there are many areas that have not been touched, with climax vegetation (mostly sagebrush and some juniper trees) that would take decades to grow. These untouched areas are even found upslope from sensitive areas, such as the high school. There doesn’t seem to be much rhyme or reason to it. The EPA claims that the problem has been solved, but my goal with this study is to provide independent evidence. Are areas inside the town still contaminated?

Headframes at the Eagle and Bluebell Mines

Headframes at the Eagle and Bluebell Mines

We had hoped that students at Tintic High School would identify and collect samples inside town, but the teacher that was going to collaborate with us bowed out because it was getting too close to the end of the year and he needed the time to prepare his students for state mandated tests. So instead, my students and I had traveled around town on our previous trips looking for candidate locations that will give us a good cross section and not cause problems with identifiable private property

Collecting samples near the High School

Collecting samples near the High School

I also wanted to get soils from a typical mineralized area that had not been mined or processed. There are a series of road cuts leading into town from the east where U.S. Highway 6 goes around several sharp turns. One of these curves cuts through a section of reddish-yellow rock and soil, the marker of a hydrothermal vein. We stopped and collected two samples, one from yellowish soil and one purplish-white. Then we drove on in to town to start collecting samples there.

We began by driving up to a dirt parking lot near the high school baseball diamond. There is an ATV track there where contamination is likely to have been stirred up by the four-wheelers and washed down a small gully through climax sagebrush and junipers. We collected inside the track, in the gully itself, and at the base of the junipers in what was undisturbed original soil.

A pump used to drain water from the mines. Power for the pump came from the Nunn brothers' hydroelectric station in Provo Canyon.

A pump used to drain water from the mines. Power for the pump came from the Nunn brothers’ hydroelectric station in Provo Canyon.

We then proceeded around town, taking samples on the surface and about six inches below at several locations, including a few empty lots, spots next to road right of ways and the city park, downslope from the Eagle and Bluebell mine dumps, and around an old house foundation that was long since abandoned and crumbling into ruin. Altogether we collected at ten sites, or twenty samples, in town. We then drove out of town to the west and collected samples from the bottom of a wash about half way down to the old CCC camp. This would be a control.

Map of Eureka, Utah

Map of Eureka, Utah

Although we needed to collect quite a few samples in a short period of time, we also took some time to explore more of the town. Around the museum, I explained to the students how the equipment worked, such as the pneumatic hammers, skip cages, water buckets, and muckers. They looked around the old jail and discovered some papers in a room underneath, including a booklet summarizing clean-up efforts after the flooding in 1983. We also found an old, yellowed map of Eureka itself. I carefully took photos of these documents and put them back where we found them. It was a sunny, warm day and we didn’t need coats even though there was still snow on the ground in places. We drove up to get some pictures of the Eagle and Bluebell mine sites. I got out of the car and walked along a hill that is covered in rip-rap to take photos of some old mine equipment and got myself stuck in a snowbank for a minute.

Mining gear at the Chief Consolidated Mining Company headquarters.

Mining gear at the Chief Consolidated Mining Company headquarters.

All told, we have about 42 samples from over 20 locations all over the district. We had identified these areas using Google Earth last fall. In addition to our sample collecting, we shot video and took photos as we traveled around town, with the intent to put all of this into a video on the history and current challenges of the town. Now for the analyses!

Plastic netting used by the EPA to slow down erosion on slopes, allowing native plants to grow.

Plastic netting used by the EPA to slow down erosion on slopes, allowing native plants to grow.

Ruined foundation of a house in Eureka. We sampled near here, since yard fill was often collected from the mine dumps.

Ruined foundation of a house in Eureka. We sampled near here, since yard fill was often collected from the mine dumps.

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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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Parked along the switchbacks from Slumgullion Pass

Parked along the switchbacks from Slumgullion Pass

I came to Lake City from the south along Highway 149, driving from Creede along the headwaters of the Rio Grande River over the Continental Divide at Spring Creek Pass (10,901 feet). After staying on the high plateau, the road climbs again to Slumgullion Pass at 11,361 feet. It then descends toward Lake City, taking a series of dramatic switchbacks. At one hairpin turn, there is a nice overlook of Lake San Cristobal and Lake City. I stopped to look at the interpretive signs and take a few photos.

The San Juan Mountains of Southwestern Colorado

The San Juan Mountains of Southwestern Colorado

I parked along the old main street of town and found a nice old-fashioned soda fountain, the San Juan Soda Company, in a store next to the historic Miners and Merchants Bank. I had a tasty mint chocolate chip shake, which really hit the spot. I asked for directions and drove northeast out of town up Henson Canyon about two miles in a slight drizzling rain for the Hard Tack Mine.

Entrance to the Hard Tack Mine near Lake City, Colorado

Entrance to the Hard Tack Mine near Lake City, Colorado

As I always do, I asked the tour guide if I could videotape the tour, and he told me to check with the owner, who was in the main office next to the mine entrance. She was afraid that I would show their tour to “the competition” and refused to let me videotape it, although she said that photographs were allowed. I tried to assure her that my reporting should help business, but she wasn’t convinced. At least this would give me a chance to take more photographs. As things turned out, I’m glad I didn’t tape the tour. The guide was fairly new, having only done this about two months. He was from out of state, and was unable to answer questions about the types of minerals found here or how mining began around Lake City (which you would think would be standard background any guide would know). Hopefully he’s done more homework since.

Mucking Machine Diagram in the Hard Tack Mine

Mucking Machine Diagram in the Hard Tack Mine

The tour itself was disappointing compared with other tours I’ve taken on my trip through Colorado. To begin with, the Hard Tack Mine wasn’t a mine at all; it was originally blasted as an adit to reach other mines further up the mountain but was abandoned after reaching only 350 feet. No ore was ever struck. The current owners came in, cleaned out the old works, blasted a few way stations to hold exhibits, brought equipment in from other places, and called it a “mine tour.” Now, if I had never been on any other mine tours (such as the one in Creede just this morning, which was far superior) then I might have learned some interesting things about hard rock mining. But the other tours at least had tour guides who had been miners and knew their stuff, and their displays were better designed and more detailed. And their mannequins were less cheesy.

Jack leg drill display in the Hard Tack Mine

Jack leg drill display in the Hard Tack Mine

There were a few good things about this tour. The displays had some illustrated signs that did a good job explaining how the drills and other equipment worked. The signs were on paper inside plastic sleeves and were hard to photograph because they didn’t lie flat, but I did the best I could. There was also a good mineral exhibit and some photographs of the mining in the area. But the tour didn’t last very long nor was it very informative. There is a museum in town that no doubt gives more details about the history of the area, but my time was short – I wanted to get to Victor before nightfall. I’ve had to do some further research on my own.

Lake City Colorado from Highway 149

Lake City Colorado from Highway 149

Lake City, Colorado is the county seat of Hinsdale County and the only incorporated town in the county, which is the most sparsely populated county in Colorado. This should tell you something about how remote the town is from just about anywhere else; although it is not very far as the eagle flies from Lake City to Ouray or Silverton, you need a good four-wheel drive vehicle to make it over Engineer or Cinnamon Pass. This silver camp is located on the west slope of the continental divide along Colorado Highway 149, northwest of Creede and southwest of Gunnison.

Lake City in 1881

Lake City in 1881

The same caldera eruptions that brought veins of silver, gold, lead, zinc, and copper to the San Juan Mountains also placed veins in this area, cut into by glaciers to form the rugged peaks and ridges of the San Juans. About 800 years ago, a large earthflow filled the canyon and damned off the Lake Fork of the Gunnison River, creating Lake San Cristobal, the second largest natural lake in Colorado. Lake City is located in a dell about three miles below this natural dam. The slide itself is called the Slumgullion Slide, because its brownish-orange color studded with boulders reminded the early miners of slumgullion stew, a beef stew with onions, carrots, and potatoes.

Lake San Cristobal above Lake City, Colorado

Lake San Cristobal above Lake City, Colorado

This area was home to various Ute tribes, especially the Tabeguache Tribe led by Chief Ouray. They originally ranged from the San Luis Valley through the San Juans. But their range was reduced through several treaties, ending with the Brunot Treaty of 1873, which moved the Utes to the Uintah-Ouray Reservation in Eastern Utah.

Lake City winter

Lake City winter

Even before the treaty was ratified, prospectors were heading into the San Juans, pressing south along Lake Fork to the area around Lake San Cristobal. One party of six men, led by Alferd Packer, got caught in deep snows as they tried to hike to the Los Pinos Indian Agency near Saguache. They ran out of food and even ate their shoe leather to try to stay alive. Only Packer made it to the station.

Alferd Packer. You would not want to hire this man as a tour guide . . .

Alferd Packer. You would not want to hire this man as a tour guide . . .

Later that year, the bodies of the other five men were found dead at the base of Slumgullion Pass and showed signs of foul play and cannibalism. Packer had seemed well enough fed, and was spending money from several different wallets. He was arrested and charged with murder, escaped, was captured seven years later and convicted of murder in the Hinsdale County Courthouse. He was retried in Gunnison and found guilty again, then sentenced to 40 years. He was later pardoned by the Governor of Colorado. He always claimed he had killed one of the men in self-defense, and that another man, the oldest of their party, had died of natural causes and was probably eaten by the others.

The Golden Fleece mines above the Slumgullion Slide.

The Golden Fleece mines above the Slumgullion Slide.

Other prospectors discovered claims, which were staked out and filed just as soon as the treaty was complete. The first big strike was the Golden Fleece claim discovered by Enos Hotchkiss (who also built the first cabin in the area of what is now Lake City). He and Henry Finley and D. P. Church were building a toll road between Silverton and Saguache in 1874 when he located rich gold ore by the lake. By 1875, Lake City was incorporated as a town, and became the county seat. Within a few years over 500 structures had been built and mining had extended all the way into the valleys and passes above Lake San Cristobal. The town itself became an important jumping off, resupply, and smelting point.

Illustrated map of Lake City, Colorado

Illustrated map of Lake City, Colorado

In 1889 the Denver and Rio Grande Railroad built a narrow gauge line in from the north and the ores could now be transported much more cheaply. Otto Mears built toll roads over the passes from Silverton and Ouray to Lake City and charged $2.25 per passenger for the daily stagecoach runs. It would take two days to make the bone-jarring ride, and the stages would stop over at Rose’s Cabin, originally built in 1874 by Corydon Rose as a one-story log cabin. It eventually grew into a saloon and hotel, stable, store, post office, and cultural center for the mining claims in the area.

Downtown Lake City, Colorado

Downtown Lake City, Colorado

Lake City reached its peak population of about 6000 around 1900, but the writing was already on the wall. The Silver Panic of 1893 cut the price of silver so much that it doomed much of the mining in the San Juan Mountains and elsewhere in Colorado and throughout the West. Only those mines that contained enough gold and other ores to ride out the downturn were able to survive. Now maybe 500 people live there year-round.

Soda fountain in Lake City, Colorado

Soda fountain in Lake City, Colorado

The last train out of Lake City left on May 25, 1933. After the railway was abandoned, Mike Burke, owner of the Ute-Ulay Mine, had a 1928 Pierce Arrow automobile remodeled with train wheels so it could run on the tracks. It was called the Galloping Goose because of its tendency to weave back and forth on the rails.

Silver ore from the Ute-Ulay Mine near Lake City, Colorado

Silver ore from the Ute-Ulay Mine near Lake City, Colorado

The Ute-Ulay (or Ule) Mine is one of the more famous in the area, with over $10 million worth of silver and lead extracted. Its mill was used as late as 1983, but now the buildings, mill site, boarding house, tram line, etc. are decaying and in danger of collapsing under heavy winter snows. The current owners, LKA International, have donated the land to Hinsdale County and options are being looked at to renovate the structures and remediate the tailings pile and pit near the mill.

Miners at the Black Creek Mine near Lake City, Colorado.

Miners at the Black Creek Mine near Lake City, Colorado.

The county invited in the nonprofit Colorado Art Ranch to put together the Hardrock Revision Team, a group of seven artists to find creative ways to utilize the property while maintaining its historic appeal. Some ideas include turning the over 100 miles of tunnels into a large Aeolian harp, converting the water tank into a camera obscura, covering the roofs of the buildings with protective tarps painted with mining scenes, and turning the tailings pit into an ice skating rink once it has been remediated. This is not a bunch of outsiders coming in to tell the community what to do – it was initiated by Lake City citizens. It will be interesting to see what happens, and perhaps I’ll have to stop when I come this way again. Here is a link to the article I found on this project: http://www.hcn.org/issues/43.20/can-an-old-mine-become-a-work-of-art/article_view?b_start:int=0. I just wish similar efforts could happen in Utah before the state shuts all our mining history down or all the old structures collapse into oblivion.

Mining structures in the Lake City area

Mining structures in the Lake City area

As I left the Hardtack Mine, I drove north out of Lake City on Highway 149 and left the San Juan Mountains behind. North of Lake City, large basalt flows continue all the way to the Black Canyon of the Gunnison. I joined U.S. 50 nine miles west of Gunnison and stopped to gas up. Now I was on a familiar road – I’ve traveled most of the length of U. S. 50 at one time or another. I’ve been on this section with my children 10 years ago when I was last in the San Juans.

Captain John W. Gunnison, for whom many towns and places are named in Colorado and Utah. His 1853 survey expedition was attacked by a Pahvant war party in Oct., 1853 west of Deseret, Utah.

Captain John W. Gunnison, for whom many towns and places are named in Colorado and Utah. His 1853 survey expedition was attacked by a Pahvant war party in Oct., 1853 west of Deseret, Utah.

Captain John William Gunnison left his name all over Colorado and into central and western Utah, but not in Nevada. He never made it that far. As a Captain of the Army Corps of Topographical Engineers, he was commissioned in 1853 to survey a route for the transcontinental railroad between the 38th and 39th parallels. U.S. 50 and parts of the Denver and Rio Grande Railroad follow the route his team surveyed. They discovered the gorge of black basalt and the river that bears his name. Once they reached Utah, they surveyed along the Sevier River near the site of Gunnison, Utah and passed through Leamington Canyon into the Pahvant Valley. Fearing the approach of winter, he sped up the work by splitting his team into two groups. His half of the party surveyed a large meander in the Sevier River where the Gunnison Bend Reservoir is now located. Several miles further down the river, west of what is now Deseret (my hometown), they were attacked by Pahvant Utes on the warpath. Of eleven men in the group, only three survived. Gunnison was killed. I travelled east on U. S. 50, thinking about how Deseret would be different if Gunnison had finished his survey and the transcontinental railroad had followed that route instead of the more northern route it took.

Hidden Treasure Mine near Lake City, Colorado

Hidden Treasure Mine near Lake City, Colorado

I became so sleepy that I had to pull over and take a nap for an hour, then press on. Clouds gathered as I drove up into the Sawatch Range and it began to drizzle. I had intended to take the tramway to the top of Monarch Pass, but I was behind schedule and it wouldn’t have been much of a view in the rain, so I pressed on. I drove into Buena Vista and ate supper at a burger place, then tried to get the phone number for the KOA campground outside of Victor that I was going to stay at. It was getting dark and I wanted to let them know I was going to be late coming in. My wife looked up the number for me (somehow I had forgotten to write it down with all my other contact information when planning this trip) as I drove east on U.S. 24. I had to double back to find a spot with cell tower reception in order to get the number, but was not able to get through to the campground. They must have already closed the office.

The Road to Gunnison

The Road to Gunnison

By now it was completely dark, so once again I travelled this highway in the night, the last time being in 2010 when we drove out to Denver, stopping in Cripple Creek. Now I was returning to complete the visit I made then. At least I had driven this route once in the daytime, back in September, 2009 on my way back from Philadelphia, and had good photos of the scenery.

My route from Lake City to Victor, Colorado on July 14, 2012.

My route from Lake City to Victor, Colorado on July 14, 2012.

I was getting very tired by the time I got to Divide and turned south. I took the turn toward Victor, but somehow missed the KOA in the dark and wound up driving all the way into town. I turned around and headed back. I almost missed the sign again. The KOA is located just south of the turnoff to Victor, and I arrived about 11:00. The manager had left a map for me in the entranceway to the office with my site circled, a tent site on the outer edge of the camp. It took a couple of drives around the camp before I found the right trail leading off to the tent sites. Mine was Site 1, nestled back in the aspens with good privacy. I was too tired to make camp, so I just rearranged my gear, setting stuff outside like the tent that I knew bears wouldn’t get in to, and made a fairly good bed in the back of my minivan.

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For the last week, I’ve been busy preparing for my classes at Walden School, including inventorying the science lab room (which is also my classroom) and planning out my course schedules. I’ll be teaching two sections of Chemistry, one of Astronomy, one of Computer Technology (a basic computer literacy course required in Utah), a section of Media Design, and a section of Video Production. This is, for me, a perfect schedule. In the meantime I’ve also been preparing a series of maps and 3D images of the Tintic Mining District, focusing on the ore deposits and the various mines located there. I’ve also prepared the script for this section of the video, which I have pasted below:

Mines in the East Tintic Mts

MInes and Roads in the East Tintic Mtns.

Tintic Geology

To understand how the ore bodies in the Tintic District were deposited, we have to start about 800 million years ago in the Precambrian Period when the western portion of the North American craton rifted away from the rest of the continent along a line where the Wasatch Front now lies – this Wasatch Line has been an important hinge line in Utah’s geology ever since. For the next 600 million years, a sequence of ocean sediments including dolomite, limestone, shale, and sandstone were deposited off the coast in the geosyncline that would become western Utah. Beginning 150 million years ago, Nevada and then western Utah were uplifted as the Farallon tectonic plate was pushed under North America. Like a throw rug being wrinkled up as it’s pushed over a hardwood floor, western Utah was folded by thrust faults into a large mountain range during the Sevier orogeny about 70 million years ago. This thrusting continued across eastern Utah and into Colorado and Wyoming during the Laramide orogeny, building up the Uintah and Rocky Mountains.

East Tintic Mines

Mines in the eastern portion of the Tintic Mining District

Then, about 50 million years ago, the Farallon plate began to collapse from underneath the continent. As it peeled away, a wave of volcanism moved from east to west across Colorado and Utah. Intrusive laccoliths rose to the surface, bulging up the LaSal and Henry Mountains in eastern Utah and forming explosive calderas in several places in western Utah. About 35 million years ago, a series of calderas formed in the area that would become the Tintic Mountains. A large andesitic volcano rose up from eruptions of ash and tuft.

Tintic Standard ore samples

Ore samples from the Tintic Standard Mine, eastern district.

About 31.5 million years ago, the volcano collapsed as the intrusive magma began to cool. Mineral rich fluids were injected into the surrounding limestone, quartzite, and dolomite as replacement beds. The hot magma caused the carbonate rocks to decompose; for example, limestone turns into lime or calcium oxide and carbon dioxide gas when heated. This left large cavities that then filled up with the mineral-laden magmas. These deposits are called stopes, such as the famous Oklahoma stope of the Chief Consolidated mine. The carbon dioxide released from the decomposing limestone and dolomite in turn dissolved into the hot magma, making it a kind of lava champagne, and reacting with it to form various exotic minerals, some of which are found nowhere else.

More Tintic ore samples

More ore samples from the Tintic District

The primary ore-bearing minerals in the Tintic District are enargite, tetrahedrite, galena, sphalerite, pyrite, marcasite, and native gold, silver, and copper. But many more minerals are present, including unusual minerals that blend copper, silver, tellurium, arsenic, sulfur, carbonates, hydrodixes, etc. At the Centennial Eureka mine, over 85 different minerals have been identified, ranging from common pyrite, malachite, and azurite to minerals found only here. It is the type locality (where the mineral was first identified) for leisingite, frankhawthorneite, jensenite, juabite, utahite, and eurekadumpite. Other rare minerals include xocomecatlite, carmenite, adamite, duftite, and mcalpineite.

These mineral deposits occurred around the edges of the caldera and formed the five large ore zones of the main Tintic District. The Gemini Ore Zone runs to the west of Eureka south to the north edge of Mammoth Gulch. The Gemini, the Bullion Beck and Champion, the Eureka Hill, and the Centennial Eureka mines (known collectively as the Big Four) are located on this zone.

The Chief-Mammoth Ore Zone begins under the center of Eureka and extends due south across the mountain to the east end of Mammoth Gulch. The Chief Consolidated mine is located on the richest ore body, which is right under the center of Eureka city; up the hill is the Eagle and Blue Bell mine, named for the beautiful deposits of azurite found inside. Further south over the top of Eureka Peak lie the Grand Central, Mammoth, Apex, and Gold Chain mines that are also part of this deposit.

Ore zones in the Tintic District

Ore Zones and Major Mines of the Tintic Mining District

The Plutus Zone branches off of the Chief-Mammoth Zone high up in the Tintic Mountains. The Godiva Zone starts just east of Eureka and runs southeast in a curve where it joins the Iron Blossom Zone, which continues in a curve south and then southwest. Some mines in these zones include the Godiva, May Day, Humbug, Beck Tunnel, Sioux, and Iron Blossom mines.

In the eastern section of the Tintic District, several zones of minerals were deposited and were among the last to be discovered because they are overlain by 400 feet of igneous rock. These bodies include the Burgin ore body, the Tintic Standard, and the North Lily bodies. Other bodies are located at the Apex and Trixie mines.

In the southern section of the Tintic District, the large replacement bodies give way to smaller fissure veins that are only two feet wide on average but can be up to 4000 feet long. Here, the mineral-bearing magma was injected into cracks and fault lines already existing in the host rocks. The Dragon mine is the only true open pit mine in the area; it sits on top of a network of fissure veins at the south end of the Iron Blossom Zone. Other mines in the area include the Swansea and Sunbeam mines at Silver City, the Tesora and Treasure Hill mines at Ruby Gulch, and the Showers mine at Diamond Gulch.

More ore samples from the Tintic Standard Mine

More ore samples from the Tintic Standard Mine

The final chapter in the area’s geomorphology began about 17 million years ago when normal faulting created the Basin and Range province, lifting up blocks to form the mountain ranges of Utah and Nevada, including the East Tintic Mountains. Other blocks sank to form the valleys, such as the Tintic Valley. Erosion has exposed the ore bodies in many places, including the outcropping that George Rust stumbled over in 1869. It was to become the Sunbeam Mine.

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    I’m sorry that I haven’t written for a couple of weeks. This last week I’ve been laid up with a kidney stone and haven’t felt up to sitting at this computer until today. If you’ve ever had one, you know why – the pain is tremendous. To keep from writhing on the floor in agony, one has to take rather strong pain medication (which I am very thankful for) and it isn’t good for one’s mental acuity. The stone was the first I’d ever had, and it came upon me suddenly last Friday morning. It wound up being large (12 mm), so this Monday evening I had a laser laproscopy to break up the stone and remove the pieces. I’m still a bit foggy and my concentration isn’t up to par yet, but I’m at least semi-vertical. If this post doesn’t make much sense, please excuse me. 

View along Hwy 24 in Colorado

View along Hwy 24 in Colorad

    At my last post I was still in Colorado on Sunday morning, Sept. 6 at Mueller State Park west of Colorado Springs. I had intended to get to Cripple Creek the evening before, but daylight ran out on me. It was a beautiful morning, and I had to decide once I left the park whether to turn right and go 12 miles to Cripple Creek and spend the day there going through the Molly Kathleen Gold Mine and the visitor’s centers or turn left and head back to Utah. I’d been on the road for six days already, and by this time I just wanted to get home, so I opted for left. Cripple Creek will have to wait for another time when I can spend a whole day there – to give it any less wouldn’t do it justice. I’ve read the book Midas of the Rockies about Winfield Scott Stratton (it’s a bit hard to find – I stumbled across a 1937 edition in our local library) and have wanted to visit Cripple Creek and the Independence Mine ever since. Perhaps next September when the aspens are turning I’ll be back this way with the funds to do it right.

Drilling competition rocks at Leadville, CO

Drilling competition rocks at Leadville, CO

 

    I turned onto CO-24 at Divide and headed west, driving through wonderful country. The few photos here don’t do it justice; once I get my health back I’ll piece together a panoramic shot. I traveled north on 24 from Buena Vista, then stopped at Leadville and took a few photos. Leadville was once the highest incorporated city in the U.S. at over 10,000 feet elevation. It was a major silver mining town and made a fortune for Horace Tabor and others, but when the price fell out of the silver market, Tabor lost his fortune. It’s quite a story, and the town still celebrates its mining heritage with Boom Days each year,

 

Silver mining ruins at Leadville, CO

Silver mining ruins at Leadville, CO

Main St. in Leadville, CO

Main St. in Leadville, CO

which includes a man-mule race to the top of Colorado’s highest peak and a hydraulic drilling competition. I’ve been through the Mining Hall of Fame here before, but didn’t have a functioning camera at the time. I’ll have to stop here as well when I make my next trip out to Colorado.

 

Mining along CO-24

Mining along CO-24

 

 

 

    I continued on the 24 through glacial valleys and around hairpin turns past old mine diggings. Some of the aspens were already beginning to turn. At Minturn I joined I-70 and continued west through Glenwood Springs, Grand Junction, and on into Utah. I stopped at the Book Cliffs to take some spectacular shots (the clouds and lighting were just right), then turned off at Green River and took US-6 through Price and on to Utah Valley and home. It was a long drive, but I managed to get home by about 6:30 to see my wife and two youngest children again after 10 days absence (they had flown back to Utah on Aug. 25).

 

The Book Cliffs, east of Green River, Utah

The Book Cliffs, east of Green River, Utah

 

    Since then I’ve started to capture the footage I took along the way and am beginning to make contacts for an advisory board for this project, which I will work on quite a bit in October. By October 22 I will have put together at least a couple of episodes. Sorry it’s taking so long, but my biggest hang up right now is simply hard drive space. We’ve been waiting for a deposit reimbursement from our Philadelphia apartment so that I can get another hard drive; the 1 TB drive I bought in May is already full, and I can’t do much more editing or capturing without more space. On October 22 I will be presenting at the Utah Museum Association conference and will show some completed episodes and footage of the Tintic Mining Museum while there. I’m also working on footage of my interview with Dr. Eric Scerri that I have promised to send him. It took some time to figure out how to capture from my Canon Vixia HD30 camera; my Final Cut Pro software can capture SD tapes from that camera just fine, but not HD. I finally got it to work by using iMovie to capture the HD tapes instead. In the meantime I also have to make a living, and since I’m not teaching any longer I’m doing some freelance video production work with a friend, and that’s taken up my spare time until this kidney stone knocked me out last weekend. 

    It’s good to be home; the weather has turned cool and rainy today, the maples and oaks on the mountains are blazing and there’s snow on the peaks of the Wasatch. Writing this post has helped me clear my head a bit, so maybe I can get some actual work done now.

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