Manila Lode is a former mine/mill facility outside the town of Montezuma, Colorado that operated from the 1870s into the 1910s during the Colorado Silver Boom. The remnants of this operation still impact the area today. Two large contiguous waste rock and mine tailing piles exist and present heavy metal contamination threats to hikers/recreationists, the Upper Snake River and a residence adjacent to the Site. Soil samples collected by Trout Unlimited in 2018 reported the presence of aluminum, arsenic, cadmium, copper, iron, lead, manganese and zinc. Lead concentrations in the pile range from 2,000 to 20,000 mg/kg. Trout Unlimited sampling results from 2019 found that much of the heavy metal contamination form the piles was reaching the Upper Snake River adjacent to the site.

In July, 2021, EPA initiated a Removal Action with the following objectives:

• Safety of the public and response personnel is top priority.
• Maintain site security to prevent public exposure.
• Minimize or, if possible, eliminate threats to human health and/or the environment posed by metal laden rock and contaminated storm water.
• Temporarily reroute storm water drainage around the waste pile to allow for waste piles to be reworked and a permanent drainage path to be constructed without the inflow of water.
• Rework and regrade the waste piles to eliminate void spaces within the piles and to eliminate the steep slopes currently present. This will minimize water infiltration through the piles as well as mitigate erosion.
• Construct a permanent lined drainage channel to take water from the Toledo Tunnel across the waste site to the wetland area without allowing direct contact with waste materials.
• Install an evapo-transpiration cover over the waste piles and establish proper vegetation to promote stabilization and mitigate direct contact with the metal laden rock.
• Provide institutional controls, such as deed restriction or an environmental covenant.
• Provide timely and accurate communication of response information to the public, on-site media, and affected stakeholders.

• Continue harvesting and stockpiling rock for waste pile stabilization.
• Complete the rough grade and stabilization of the upper portions of the waste piles.
• Continue the temporary diversion around the Site of the discharge from the Toledo Tunnel.

The EPA Team (ERRS crew, START Contractor, and EPA personnel) worked Monday through Saturday (July 19 to July 24).  Operations were hampered by afternoon thunderstorms and lightning, which caused early departures from the Site Tuesday through Saturday.  Personnel and Heavy equipment used on-site  this period included: 

• 2 Excavators
• 1 Bulldozer
• 1 Front End Loader
• Vibratory Roller/ Compactor
• 1 500- Gallon Water Tank/ Pump Unit
• EPA Mobile Command Truck
• 5 ERRS Crew
• 2 EPA
• 1 START (July 23 only)

The rough grading of the upper portion of the waste pile was completed on Saturday, July 24, 2021.  This section is ready for rocking, drainage ditch installation, topsoil, and vegetation.

The crew continued to collect and segregate large rocks/boulders (>1' diameter) for use in drainage ditches and pile stabilization.  A portion of this rock was put in place along the toe of the upper waste pile.

• Complete the Installation of rock stabilization structures along the toe of all steeper slopes of the upper waste pile.
• Cut, line, and rock the permanent Toledo Tunnel discharge channel over the upper waste pile.
• Begin stabilization work on the lower portions of the wastes piles.
• Collect and segregate large boulders/rocks from waste piles for use in pile stabilization.

For the Operational Period of July 26 to August 1, 2021, the OSC established the following objectives:

• Complete the installation of rock stabilization structures along the toe of all steeper slopes of the upper waste pile.
• Cut, line, and rock the permanent Toledo Tunnel discharge channel over the upper waste pile.
• Begin stabilization work on the lower portions of the waste piles.
• Collect and segregate large boulders/rocks from waste piles for use in pile stabilization.
• Award subcontracts for the purchase of common fill; compost; topsoil; road base; and rip-rap.

During the Current Operational Period the EPA Site Team worked Monday thru Saturday. Operations were hampered by a series of heavy afternoon thunderstorms and lightning. During this period the Team:

• Installed rock stabilization structures along the south flank and toe of the waste pile, and along the base of the upper portion of the pile.
• Completed cutting and rocking all drainage ditches and structures on the upper portion of the pile.
• Began cutting and placing a synthetic liner for the permanent Toledo Tunnel discharge channel over the upper portion of the Site.  However, the channel remains to be rocked.
• Continued harvesting large rock from the Site for use as stabilizing rip-rap.
• Began taking delivery of the needed construction materials (e.g., common fill, rip-rap, road base, erosion mat, compost, etc.)
• Began placing fill and rip-rap on the upper portion of the waste pile.
• Began grading the top portion of the lower waste pile.

For the next Operational Period, August 2 thru August 8, 2021, the EPA Site Team Plans to:

• Complete construction of the lined drainage channel on the upper pile.
• Begin construction of the lined drainage channel over the lower pile.
• Continue construction of Site drainage features, including run-on/run-off controls.
• Finish grading the pile.
• Continue cover installation of soil cap.
• Purchase vegetation seed mix.

For the Operational Period of August 2 to August 15, 2021, the OSC established the following objectives:

• Continue stabilization work on the lower portions of the waste piles.
• Place erosion control mats on the slopes to prevent erosion.
• Construct drainage channels on top and middle sections of pile to prevent erosion from excess water flow.
• Collect and segregate large boulders/rocks from waste piles for use in pile stabilization.
• Use topsoil to fill gaps between rocks that is used to stabilize the steeper slopes.
• Spread seeding on topsoil for new vegetation growth.

During the Current Operational Period, operations were hampered by a series of heavy afternoon thunderstorms and lightning. During this period the Team:

• Added rocks to the drainage channel on the middle section.
• Began construction of drainage channel for upper and lower portions of waste pile.
• Continued harvesting large rock from the site for use as stabilizing rip-rap.
• Began adding rip-rap and topsoil to middle section of the pile.
• Added Erosion control matting on the top and lower sections of the pile.
• Began grading the top portion of the lower waste pile.
• Added road base along the Pedestrian trail and outlined the trail boundary with rock.
• Seeding was spread on topsoil that was placed between the gaps where rock was placed to stabilize the steep slopes.

For the next Operational Period, August 16 through August 22, 2021, the EPA Site Team Plans to:

• Add rocks to the drainage channel located within the middle section of the pile.
• Continue construction of the lined drainage channel from the middle to the bottom section.
• Continue construction of Site drainage features, including run-on/run-off controls.
• Begin adding erosion control matting material on the middle section of the pile.

For the Operational Period of August 16  to August 22, 2021, the OSC established the following objectives:

• Continue adding rocks to the drainage channel located within the middle section of the pile.
• Continue construction of the lined drainage channel from the middle to the bottom section.
• Continue construction of Site drainage features, including run-on/run-off controls.
• Add erosion control matting to middle section of the pile 

During the subject Operational Period, operations were hampered by a series of heavy afternoon thunderstorms and lightning. During this period the Site Team:

• Completed regrading the top portion of the lower waste pile and continued placement of erosion control matting matting material.
• Completed rock channeling for the permanent Toledo Tunnel discharge channel over the upper portion of the Site.
• Completed placement of culvert, continued regrading and placement of erosion control matting material in middle section of pile.
• Continued construction of drainage channel for lower portion of waste pile.

For the next Operational Period, August 23 through August 29, 2021, the EPA Site Team Plans to:

• Continue placement of erosion control matting and topsoil on upper and middle levels.
• Continue construction of the lined drainage channel from the middle to the bottom section, including channel excavation and rock armoring. 
• Continue construction of Site drainage features, including run-on/run-off controls.

For the Operational Period of August 23 to August 29, 2021, the OSC established the following objectives:

• Continue erosion control matting of upper and middle sections.
• Continue construction of the lined drainage channel from the middle to the bottom section.
• Continue construction of Site drainage features, including run-on/run-off controls.

During this period the Site Team:

• Completed placement of erosion control matting and topsoil on upper and middle levels.
• Added rocks to the drainage channel located within the middle section of the pile.
• Completed construction of the lined drainage channel from the middle to the bottom section, including channel excavation and rock armoring. 
• Opened and restored water flow to the Toledo Tunnel drainage channel.
• Continued construction of Site drainage features, including run-on/run-off controls.

For the next Operational Period, August 30 through September 5, 2021, the EPA Site Team Plans to:

• Add road base to driveway and continue ditch construction along driveway.
• Placement of rock, topsoil, and erosion control matting on lower level and slope down to road.
• Continue construction of Site drainage features, including run-on/run-off controls.

During this period the Site Team:

• Completed ditch construction and added rock along driveway. 
• Added and compacted road base on Site driveway.
• Completed placement of rock, topsoil, and erosion control matting on lower level.
• Continued construction of Site drainage features, including run-on/run-off controls.
• Conducted UAS drone survey of Site on September 2.

For the next Operational Period, September 6 through September 12, 2021, the EPA Site Team Plans to:

• Complete construction of Site drainage features.
• Complete placement of rock, topsoil, and erosion control matting on slope down to road.
• Complete Site restoration activities including vegetative cover.
• Demobilize crew and equipment from the Site by September 11. 

For the Operational Period of September 6 to September 12, 2021, the OSC established the following objectives:

• Complete placement of rock, topsoil, and erosion control matting on lower level and slope down to road.
• Completed Site restoration activities including vegetative cover.
• Demobilize crew and equipment from the Site by September 10.

During the Current Operational Period, the Team:

• Completed construction of Site drainage features.
• Completed placement of rock, topsoil, and erosion control matting on slope down to road.
• Demobilized crew on September 10.

For the next Operational Period, September 12 through September 21, 2021, the EPA Site Team Plans to:

• Complete the demobilization of heavy machinery from the site.

EPA is mobilizing to the Manila Lode Site to adjust some of the drainage features installed last year, and perform some routine maintenance at the Site.  For the Operational Period of August 22 to August 29, 2022, the OSC established the following objectives:

• Complete the mobilization of equipment and personnel
• Construct a drainage channel along the base of the middle mound
• Re-dig and re-rock the drainage channel along the base of the upper mound
• Re-seed the less vegetated areas of the repository for erosion control
• Construct a small drainage channel across the road on the middle mound
• Construct 3 rock aprons around the sides of the lower mound in high flow areas
• Begin grading the road and top of the lower mound to guide surface flow towards the new and existing drainage channels
• Remove eroded soil from the culvert and ditch along Montezuma Road
• Repair erosion damage and add road base in eroded areas

During the current operational period of August 22 through August 29, 2022, the team has:

• Completed the mobilization of equipment and personnel
• Constructed the drainage channel along the base of the middle mound
• Re-dug and re-rocked the drainage channel along the base of the upper mound
• Re-seeded the less vegetated areas of the repository for erosion control
• Constructed the small drainage channel across the road on the middle mound
• Constructed 3 rock aprons around the sides of the lower mound in high flow areas
• Graded the road and top of the lower mound to guide surface flow towards the new and existing drainage channels
• Removed eroded soil from the culvert and ditch along Montezuma Road
• Repaired erosion damage and added road base in select areas

All of this operational period objectives were completed including the demobilization of personnel and equipment. Notices for further planned activities and future maintenance will be provided as necessary