The Uintah Mining District Site (Site) is located in the Silver Creek and Mcloed Creek watersheds in and around Park City in Summit County, Utah. Mining began in the area around 1869 and the mining district produced substantial quantities of ore between 1875 and 1982. Mining activities involved tunnels to extract ore, tramways and railroads to transport ore, and milling facilities to process ore. As a result of these activities, tailings and other mine waste containing lead and other heavy metals were deposited throughout the area.

In 2015, EPA’s removal evaluation of the Site identified soil contaminated with lead and arsenic at the surface of the Treasure Mountain Junior High School and its adjacent recreation fields. EPA also found contaminated soil eroding from remnant mine waste piles in Ontario Canyon, Empire Canyon, Upper Woodside Gulch, Thaynes Canyon and Treasure Hollow. These particular waste piles are considered source areas of contamination and are found on properties owned by United Park City Mines (UPCM).

UPCM's parent company, a Talisker Affiliate, leases several properties in Upper Woodside Gulch, Thaynes Canyon and Treasure Hollow to Vail Resorts for its operation of the Park City Mountain Resort. Upper Woodside Gulch including King Road and Treasure Hollow provide critical access to both summer and winter visitors and workers at the resort.

In 2016, EPA completed a time-critical removal action at the Treasure Mountain Junior High School and its adjacent recreation fields. This action removed contaminated soil from the surface and restored the property to its full use.

In 2015-2017, UPCM constructed erosion control features at mine waste piles in Ontario Canyon, Empire Canyon, Upper Woodside Gulch and Thaynes Canyon in accordance with an Administrative Order on Consent.

In Spring 2018, serious erosion issues re-emerged at Treasure Hollow during snowmelt. UPCM performed repairs at Treasure Hollow in Fall 2018 after EPA issued UPCM a Notice of Work Takeover. UPCM's efforts were not effective and the same erosion patterns developed during Spring 2019. UPCM again failed to act and EPA issued another Notice of Work Takeover. UPCM did not resolve the deficiencies that led to EPA's Notice of Work Takeover and EPA began construction activities at Treasure Hollow on August 30, 2019 to repair the damage and prevent future erosion.

In Fall 2019, EPA installed new culverts, regraded much of the Treasure Hollow waste pile, constructed rocked ditches to capture runoff and drain it away from the waste pile, restored and reseeded disturbed areas, and installed temporary erosion control features such as erosion mat, waddles, etc.

EPA's goals during this Operational Period (September 2-8, 2019) were to:

   1. Mobilize equipment and personnel.

   2. Install temporary fencing and signage.

   3. Establish rough drainage plan.

   4. Excavate interception ditches at the top of the waste pile and begin excavation of drainage ditches along the access road.

   EPA began mobilizing equipment and personnel to the Site on August 31, 2019. This mobilization will continue over the next week and EPA should be at full strength by the end of the next Operational Period (September 15, 2019). EPA will be working 6 days a week (taking Sundays off). EPA will establish weekly Operational Periods which will begin on Monday mornings. Weekly updates for each Operational Period will normally be distributed to stakeholders Mondays by noon.

   This past week, EPA's crew installed temporary fencing at key locations to delineate construction zones and warn hikers, bikers, runners and motorists of potential hazards. The crew also placed the following sign at several locations around Treasure Hollow where visitors frequent: Treasure Hollow Sign.

   EPA identified at least 3665 feet of erosion control ditches that need to be repaired and/or constructed. These ditches include:

     a) Interception ditches at the top of the waste pile (500 feet).

     b) Interception ditches on the east side of the waste pile (310 feet).

     c) Drainage ditches along the access road (1265 feet).

     d) Drainage ditches along the west flank of the waste pile (690 feet).

     e) Drainage ditches along the east flank of the waste pile (600 feet).

     f) Drainage ditch on the waste pile near the toe (300 feet).

   Most ditches will be excavated to a standard size of 10 feet wide and 4 feet deep and lined with erosion fabric and angular rock that is 12 inches or greater. The sizes of the ditches and liner rock will vary according to site conditions. The rock may be grouted with concrete in places for added stability.

   Crews completed excavation of roughly 500 feet of interception trenches at the top of the waste pile and another 500 feet of ditch along the access road. Topsoil was saved for later use and mine waste was moved to the bottom of the waste pile where it will ultimately be capped. EPA is using a water truck to actively control dust emissions during these activities.

   EPA plans to perform the following activities during the next Operational Period (September 9-15, 2019):

   - Continue mobilizing resources.

   - Continue excavation of drainage ditches along the access road.

   - Excavate interception trenches on the east side of the waste pile.

   EPA's goals during this Operational Period (September 9-15, 2019) were to:

   - Continue mobilizing resources.

   - Continue installing temporary barriers and signage.

   - Continue excavation of drainage ditches along the access road.

   - Begin excavation of drainage ditches on the west flank and bottom of the waste pile.

   - Begin regrading the west flank of the waste pile.

   EPA added a project manager, two response technicians, a field accountant, an off-road haul truck, a water truck and a skid steer to the 3 technicians, excavator and front end loader that were on-site during the previous Operational Period. EPA plans to add 3-5 more technicians, a second off-road haul truck, and a second excavator over the next Operational Period.

   EPA's crew installed and continues to maintain temporary fencing at key locations to delineate construction zones and warn hikers, bikers, runners and motorists of potential hazards. The crew placed the following sign at several locations around Treasure Hollow where visitors frequent: Treasure Hollow Sign.

   EPA completed excavation of the drainage ditches along the uphill side of the access road that crosses the waste pile and the drainage ditch along the west flank and bottom of the waste pile.

  EPA also began regrading the west flank by cutting and filling material in the north west section of the waste pile. Stormwater which had collected at the toe of the waste pile was drained during this regrading effort.

   At this time, EPA is planning to conduct following response activities. These activities may change as the response progresses.

- Mobilize equipment and resources (In Progress).

- Install temporary barriers and signage (In Progress).

- Construct approximately 3665 feet of ditches to capture runoff and drain it away from the waste pile. Note that most ditches will be excavated to a standard size of 10 feet wide and 4 feet deep and then lined with both erosion fabric and angular rock sized 12 inches or greater. The sizes of the ditches and liner rock may vary according to site conditions and the rock in the ditches may be grouted with concrete in places for added stability.

     a) 500 feet of interception trenches on the south side (top) of the waste pile (In Progress).

     b) 310 feet of interception trenches on the east side of the waste pile (Not Started).

     c) 1265 feet of drainage ditches on both sides of the access road that crosses the waste pile (In Progress).

     d) 690 feet of drainage ditches along the west flank and bottom of the waste pile (In Progress).

     e) 600 feet of drainage ditches along the east flank of the waste pile (Not Started).

     f) 300 feet of drainage ditches at the toe of the waste pile (Not Started).

- Bury snow making power lines deeper and insulate the associated water lines as they cross the access road (Not Started).

- Regrade the west flank of the waste pile (In Progress).

- Regrade the lower waste pile and reconstruct appropriate water bars (Not Started).

- Install a culvert across the access road along the west flank as the road leaves the Site (Not Started).

- Repair access road for use by search and rescue, ambulance and other emergency response vehicles. Repairs are not being designed for use as a daily service road nor for use by heavy equipment at this time (Not Started).

- Restore and reseed all disturbed areas (Not Started).

- Install temporary erosion control features such as erosion mat, waddles, etc (Not Started).

- Demobilize equipment and resources (Not Started).

EPA's objectives during this Operational Period (September 16 - 22, 2019) were to:

1. Continue mobilizing equipment and resources.

2. Maintain temporary barriers and signage.

3. Continue rough excavation of interception and drainage ditches and begin installing erosion fabric and rip rap.

4. Begin regrading the lower section and west flank of the repository.

EPA continued mobilizing equipment and resources. EPA currently has 2 excavators, 1 loader, 1 bulldozer, 1 off-road haul truck, 1 skid steer, 1 water truck and 10 personnel on-site. EPA anticipates adding another off-road haul truck and operator.

EPA has installed temporary barriers and signage across the Site to delineate construction zones and direct the flow of Vail personnel as well as runners, hikers and bikers. The trail at the base of waste pile has been temporarily re-routed. High winds frequently impact the barriers delineating construction zones and the crew continues to maintain their placement.

Working top to bottom, EPA has completed excavation of all our ditches and trenches except for the ditch along the east flank of the repository. Crews have completed laying erosion fabric in the interception trenches at the top (north) of the waste pile and started laying fabric in the primary ditch along the access road which crosses the pile. UPCM has begun hauling the rock that will be used to rip rap the ditches to the base of the ski resort and EPA is bringing it up to Treasure Hollow.

EPA started regrading the lower portion of the repository during this Operational Period. When the snow making lines and vaults were installed in 2017, they were placed down the center of the repository at a grade that is lower than the surrounding mine waste. This has resulted in a situation where runoff is directed towards the center of the repository and down the snow making lines as opposed to towards the edges and off the repository. The crew needs to raise the grade at the center of the pile but there is one snow making vault that is particularly problematic. EPA is looking at ways to raise the grade of the repository while still controlling runoff from this low point but the owner/operator will need to maintain physical barriers to keep skiers away from this location if the repository is to continue being used as a ski run in the winter.

In addition, EPA completed regrading the west flank of the repository below the access road except for an area just below the road near a stand of trees.

At this time, EPA is planning to conduct following response activities. These activities may change as the response progresses.

- Mobilize equipment and resources (In Progress).

- Install temporary barriers and signage (Complete).

- Construct approximately 3665 feet of ditches to capture runoff and drain it away from the waste pile. Note that most ditches will be excavated to a standard size of 10 feet wide and 4 feet deep and then lined with both erosion fabric and angular rock sized 12 inches or greater. The sizes of the ditches and liner rock may vary according to site conditions and the rock in the ditches may be grouted with concrete in places for added stability.

     a) 500 feet of interception trenches on the south side (top) of the waste pile (In Progress).

     b) 310 feet of interception trenches on the east side of the waste pile (In Progress).

     c) 1265 feet of drainage ditches on both sides of the access road that crosses the waste pile (In Progress).

     d) 690 feet of drainage ditches along the west flank and bottom of the waste pile (In Progress).

     e) 600 feet of drainage ditches along the east flank of the waste pile (In Progress).

     f) 300 feet of drainage ditches at the toe of the waste pile (In Progress).

- Bury snow making power lines deeper and insulate the associated water lines as they cross the access road (Not Started).

- Regrade the west flank of the waste pile (In Progress).

- Regrade the lower waste pile and reconstruct appropriate water bars (In Progress).

- Install a culvert across the access road along the west flank as the road leaves the Site (Not Started).

- Repair access road for use by search and rescue, ambulance and other emergency response vehicles. Repairs are not being designed to support use as a daily service road nor for use by heavy equipment until a responsible entity can be identified for long-term maintenance (Not Started).

- Restore and reseed all disturbed areas (Not Started).

- Install temporary erosion control features such as erosion mat, waddles, etc (Not Started).

- Demobilize equipment and resources (Not Started).

EPA's objectives during this Operational Period (September 23 - 29, 2019) were to:

1. Finish mobilizing equipment and resources.

2. Maintain temporary barriers and signage.

3. Continue dust suppression.

4. Continue construction of drainage ditches.

5. Continue regrading the lower section of the repository.

6. Excavate snowmaking power lines to be buried deeper.

EPA completed mobilizing equipment and resources to the Site. EPA currently has 2 excavators, 1 loader, 1 bulldozer, 2 off-road haul truck, 1 skid steer, 1 water truck and 12 personnel on-site.

EPA installed temporary barriers and signage across the Site to delineate construction zones and direct the flow of Park City Mountain Resort personnel as well as runners, hikers and bikers. The trail at the base of waste pile has been temporarily re-routed and was completely closed on September 26 and 27 to allow for the installation of rip rap in a drainage ditch right above the trail. EPA coordinated this closure with Vail Resorts, Park City Municipal and local trail stakeholders.

EPA continued using a water truck to suppress dust emissions along the ski resort access road and at the Site.

EPA is excavating erosion control ditches and lining them with fabric and rip rap. Working top to bottom, EPA completed rough excavation of all the ditches. The crew also completed installing fabric and rip rap in the ditches at the top (south) of the waste pile. The crew also continued installing fabric and rip rap in the primary ditch along the access road which crosses the pile. UPCM continued hauling the rock used to rip rap the ditches to the base of Park City Mountain Resort and EPA continued bringing the rock up a ski resort access road to Treasure Hollow. To date, EPA has hauled approximately 2300 cubic yards of rock up to Treasure Hollow. UPCM also provided EPA with 3 cubic yards of crushed rock for use repairing rut in the access road up the ski resort.

EPA continued regrading the lower portion of the repository during this Operational Period. When the snow making lines and vaults were installed in 2017, they were placed down the center of the repository at a grade that is lower than the surrounding mine waste. This has resulted in a situation where runoff is directed towards the center of the repository and down the snow making lines as opposed to towards the edges and off the repository. The crew needs to raise the grade at the center of the pile but there is one snow making vault that is particularly problematic. EPA changing the grade of the repository and installing new water bars to better control runoff and erosion of the waste pile.

EPA began excavating the power lines between two snowmaking vaults so they can be buried deeper to allow for construction of a drainage ditch along the access road.

At this time, EPA is planning to conduct following response activities. These activities may change as the response progresses.

- Mobilize equipment and resources (Complete).

- Install temporary barriers and signage (Complete).

- Construct approximately 3665 feet of ditches to capture runoff and drain it away from the waste pile. Note that most ditches will be excavated to a standard size of 10 feet wide and 4 feet deep and then lined with both erosion fabric and angular rock sized 12 inches or greater. The sizes of the ditches and liner rock may vary according to site conditions and the rock in the ditches may be grouted with concrete in places for added stability.

     a) 500 feet of interception trenches on the south side (top) of the waste pile (Complete).

     b) 310 feet of interception trenches on the east side of the waste pile (Not Started).

     c) 1265 feet of drainage ditches on both sides of the access road that crosses the waste pile (In Progress).

     d) 690 feet of drainage ditches along the west flank and bottom of the waste pile (In Progress).

     e) 600 feet of drainage ditches along the east flank of the waste pile (In Progress).

     f) 300 feet of drainage ditches at the toe of the waste pile (In Progress).

- Bury snow making power lines deeper and insulate the associated water lines as they cross the access road (In Progress).

- Regrade the west flank of the waste pile (In Progress).

- Regrade the lower waste pile and reconstruct appropriate water bars (In Progress).

- Install a culvert across the access road along the west flank as the road leaves the Site (Not Started).

- Repair access road for use by search and rescue, ambulance and other emergency response vehicles. Repairs are not being designed to support use as a daily service road nor for use by heavy equipment until a responsible entity can be identified for long-term maintenance (Not Started).

- Restore and reseed all disturbed areas (Not Started).

- Install temporary erosion control features such as erosion mat, waddles, etc (Not Started).

- Demobilize equipment and resources (Not Started).

EPA's objectives during this Operational Period (September 30 - October 6, 2019) were to:

1. Maintain temporary barriers and signage.

2. Continue dust suppression.

3. Continue construction of drainage ditches.

4. Continue regrading lower portion of the repository.

5. Bury snow making power lines deeper as they cross the access road.

EPA maintained temporary barriers and signage across the Site to delineate construction zones and direct the flow of Park City Mountain Resort personnel as well as runners, hikers and bikers. The trail at the base of repository has been temporarily re-routed and the access road across the face was periodically closed as EPA rerouted power lines and constructed a drainage ditch. EPA anticipates a complete closure of the access road for several days on or after October 10 to install a culvert across the road.

EPA continued using a water truck to suppress dust emissions along the ski resort access road and at the Treasure Hollow repository.

EPA is excavating erosion control ditches and lining them with fabric and rip rap. Working top to bottom, EPA completed rough excavation of all the ditches. The crew also completed installing fabric and rip rap in the ditches at the top (south) of the waste pile, along most of the access road, along the eastern flank, and along the lower portion of the western flank. UPCM continued hauling the rock used to rip rap the ditches to the base of Park City Mountain Resort and EPA continued bringing the rock up a ski resort access road to Treasure Hollow. To date, EPA has hauled approximately 4,000 cubic yards of rock up to Treasure Hollow.

EPA continued regrading the lower portion of the repository during this Operational Period. When the snow making lines and vaults were installed in 2017, they were placed down the center of the repository at a grade that is lower than the surrounding mine waste. This has resulted in a situation where runoff is directed towards the center of the repository and down the snow making lines as opposed to towards the edges and off the repository. The crew needs to raise the grade at the center of the pile but there is one snow making vault that is particularly problematic. EPA changing the grade of the repository and installing new water bars to better control runoff and erosion of the waste pile.

EPA replaced the power lines between two snow making vaults on either side of the access road that crosses the repository so that they could be buried deeper and allow for construction of a drainage ditch along the access road.

At this time, EPA is planning to conduct following response activities. These activities may change as the response progresses.

- Mobilize equipment and resources (Complete).

- Install temporary barriers and signage (Complete).

- Construct approximately 3665 feet of ditches to capture runoff and drain it away from the waste pile. Note that most ditches will be excavated to a standard size of 10 feet wide and 4 feet deep and then lined with both erosion fabric and angular rock sized 12 inches or greater. The sizes of the ditches and liner rock may vary according to site conditions and the rock in the ditches may be grouted with concrete in places for added stability.

     a) 500 feet of interception trenches on the south side (top) of the waste pile (Complete).

     b) 310 feet of interception trenches on the east side of the waste pile (Not Started).

     c) 1265 feet of drainage ditches on both sides of the access road that crosses the waste pile (In Progress).

     d) 690 feet of drainage ditches along the west flank and bottom of the waste pile (In Progress).

     e) 600 feet of drainage ditches along the east flank of the waste pile (In Progress).

     f) 300 feet of drainage ditches at the toe of the waste pile (Not Started).

- Bury snow making power lines deeper and insulate the associated water lines as they cross the access road (Complete).

- Regrade the west flank of the waste pile (In Progress).

- Regrade the lower waste pile and reconstruct appropriate water bars (In Progress).

- Install a culvert across the access road along the west flank as the road leaves the Site (Not Started).

- Repair access road for use by search and rescue, ambulance and other emergency response vehicles. Repairs are not being designed to support use as a daily service road nor for use by heavy equipment until a responsible entity can be identified for long-term maintenance (Not Started).

- Restore and reseed all disturbed areas (Not Started).

- Install temporary erosion control features such as erosion mat, waddles, etc (Not Started).

- Demobilize equipment and resources (Not Started).

EPA's objectives during this Operational Period (October 7 - 13, 2019) were to:

1. Maintain temporary barriers and signage.

2. Continue dust suppression.

3. Continue construction of drainage ditches.

4. Install culverts under access road and Jenny's Trail.

5. Grout in culverts and nearby rock work. 

6. Continue regrading lower portion of the repository.

EPA maintained temporary barriers and signage across the Site to delineate construction zones and direct the flow of Park City Mountain Resort personnel as well as runners, hikers and bikers.

EPA continued using a water truck to suppress dust emissions along the ski resort access road and at the Treasure Hollow repository.

EPA completed construction of most of the erosion control ditches. UPCM stopped hauling rock used to rip rap the ditches to the base of Park City Mountain Resort on Tuesday, October 8th. To date, EPA has hauled roughly 5,080 cubic yards of rock up to Treasure Hollow and plans to procure another several hundred additional cubic yards of rock to complete its effort.

EPA closed the access road that crosses the repository from Wednesday, October 9, through Saturday, October 12th, while installation of a 4 foot culvert under the access road occurred. Notifications of closures to stakeholders were made the week prior as well as the morning of the closure. EPA also installed a series of culverts under Jenny's Trail at the base of the repository. One additional culvert is yet to be installed under Jenny's Trail as it enters the Site from the east. The installed culverts and nearby rock work were also grouted in during this period.    

EPA continued regrading the lower portion of the repository during this Operational Period.

At this time, EPA is planning to conduct following response activities. These activities may change as the response progresses.

- Mobilize equipment and resources (Complete).

- Install temporary barriers and signage (Complete).

- Construct approximately 3665 feet of ditches to capture runoff and drain it away from the waste pile. Note that most ditches will be excavated to a standard size of 10 feet wide and 4 feet deep and then lined with both erosion fabric and angular rock sized 12 inches or greater. The sizes of the ditches and liner rock may vary according to site conditions and the rock in the ditches may be grouted with concrete in places for added stability.

     a) 500 feet of interception trenches on the south side (top) of the waste pile (Complete).

     b) 310 feet of interception trenches on the east side of the waste pile (In Progress).

     c) 1265 feet of drainage ditches on both sides of the access road that crosses the waste pile (Complete).

     d) 690 feet of drainage ditches along the west flank and bottom of the waste pile (Complete).

     e) 600 feet of drainage ditches along the east flank of the waste pile (Complete).

     f) 300 feet of drainage ditches at the toe of the waste pile (No Longer Required).

- Bury snow making power lines deeper and insulate the associated water lines as they cross the access road (Complete).

- Regrade the west flank of the waste pile (In Progress).

- Regrade the lower waste pile and reconstruct appropriate water bars (In Progress).

- Install a culvert across the access road along the west flank as the road leaves the Site (Complete).

- Repair access road for use by search and rescue, ambulance and other emergency response vehicles. Repairs are not being designed to support use as a daily service road nor for use by heavy equipment until a responsible entity can be identified for long-term maintenance (Not Started).

- Restore and reseed all disturbed areas (Not Started).

- Install temporary erosion control features such as erosion mat, waddles, etc (Not Started).

- Demobilize equipment and resources (Not Started).

EPA's objectives during this Operational Period (October 14 - 20, 2019) were to:

1. Maintain temporary barriers and signage.

2. Continue dust suppression.

3. Complete construction of drainage ditches.

4. Complete regrading lower portion of the repository.

5. Install water bars, erosion fabric and waddles.

EPA maintained temporary barriers and signage across the Site to delineate construction zones and direct the flow of Park City Mountain Resort personnel as well as runners, hikers and bikers.

EPA continued using a water truck to suppress dust emissions along the ski resort access road and at the Treasure Hollow repository.

EPA completed construction of the erosion control ditches. In total, EPA utilized roughly 5,500 cubic yards of rock. Approximately 5000 cubic yards were provided by UPCM.

EPA completed regrading the lower portion of the repository during this Operational Period.

EPA installed 3 water bars on the lower repository and repaired several water bars on the upper repository. Erosion fabric and waddles were also installed in key areas.

In addition, EPA repaired several areas on the access road up to Treasure Hollow including replacing rock at the transition to pavement at the bottom of the road.

EPA completed all of the following planned activities at Treasure Hollow and will re-assess conditions in Spring, 2020 after snowmelt runoff.

- Mobilize equipment and resources (Complete).

- Install temporary barriers and signage (Complete).

- Construct approximately 3665 feet of ditches to capture runoff and drain it away from the waste pile. Note that most ditches will be excavated to a standard size of 10 feet wide and 4 feet deep and then lined with both erosion fabric and angular rock sized 12 inches or greater. The sizes of the ditches and liner rock may vary according to site conditions and the rock in the ditches may be grouted with concrete in places for added stability.

     a) 500 feet of interception trenches on the south side (top) of the waste pile (Complete).

     b) 310 feet of interception trenches on the east side of the waste pile (Complete).

     c) 1265 feet of drainage ditches on both sides of the access road that crosses the waste pile (Complete).

     d) 690 feet of drainage ditches along the west flank and bottom of the waste pile (Complete).

     e) 600 feet of drainage ditches along the east flank of the waste pile (Complete).

     f) 300 feet of drainage ditches at the toe of the waste pile (Not Required).

- Bury snow making power lines deeper and insulate the associated water lines as they cross the access road (Complete).

- Regrade the west flank of the waste pile (Complete).

- Regrade the lower waste pile and reconstruct appropriate water bars (Complete).

- Install a culvert across the access road along the west flank as the road leaves the Site (Complete).

- Repair access road for use by search and rescue, ambulance and other emergency response vehicles. Repairs are not being designed to support use as a daily service road nor for use by heavy equipment until a responsible entity can be identified for long-term maintenance (Complete).

- Restore and reseed all disturbed areas (Complete).

- Install temporary erosion control features such as erosion mat, waddles, etc (Complete).

- Demobilize equipment and resources (Complete).