2.1.1 Narrative
2.1.1.1 Current Situation
During this period the ERRS contractor excavated uranium mine waste on one the most difficult areas of the site. The slope below the former mine is an approximate 60 degree slope rocky slope covered in loose mine waste. The slope begins at the top edge of Oljato Mesa and extends down approximately 200 feet before terminating in a sheer vertical face 600 feet above the valley floor. Expert equipment operators were able to carefully work an excavator down the slope and move mine waste back up to the top of the mesa, where it was transported into the repository. Due to the rocky nature of the slope, it was difficult for the excavator to get solid footing and the machine was anchored with cable to a bulldozer at the top of the mesa. A long-reach excavator, with a 65 foot reach, was used to remove mine waste approximately 100 feet below the edge of the mesa. This difficult, dangerous work was performed safely and the ERRS contractor deserves recognition for this accomplishment.
Another major progress step made during this period was the set-up of the skyline cable yarder system. The skyline with a dredge bucket will be used to remove remaining mine waste on the lower 100 feet of the upper slope and a yarder bucket will be used to transport excavated mine waste from the valley floor to the repository on top of Oljato Mesa. Coincidentally, the skyline subcontract company is named “Skyline” just like the old mine (no connection to the former mine operator). When the mine was in operation a similar skyline system was used to transport uranium ore down to the valley floor for transport to a mill.
June 6 – 11, 2011
OSC Musante onsite this week.
This week ERRS:
-Continued water conveyance system operations.
-Continued site-wide road improvements and maintenance.
-Continued dust control program using water for dust suppression.
-Continued excavation, using a long-reach excavator, on upper slope area below mine opening.
-Completed moving stockpiled AML materials into repository.
-Completed excavation, using a long-reach excavator, on upper slope area below mine opening.
-Completed decontamination of heavy equipment used on top of mesa and transport to north side excavation work zones.
-Began setup of the skyline cable yarder system.
-Began excavation and stockpiling of soils in the Arroyo area. Stockpiled materials were coated with soil sealant to prevent migration.
START delineated excavation extent in the Arroyo area, performed air sampling around work zones as part of the effluent dust sampling program, and performed radiation surveys as needed.
June 13 – 18, 2011
OSC Musante onsite this week.
This week ERRS:
-Continued water conveyance system operations.
-Continued site-wide road improvements and maintenance.
-Continued dust control program using water for dust suppression.
-Continued excavation, using a long-reach excavator, on upper slope area below mine opening.
-Continued excavation and stockpiling of soils in the Arroyo area. Stockpiled materials were coated with soil sealant to prevent migration.
-Completed setup of the skyline yarder system.
-Completed development of a new construction water supply well on the north side of Oljato Mesa.
-Began transport of stockpiled mine waste materials to top of mesa via the skyline cable yarder.
START delineated excavation extent in the Arroyo area, performed air sampling around work zones as part of the effluent dust sampling program, and performed radiation surveys as needed.
2.1.2 Response Actions to Date
Mobilization for removal activities and site setup began the week of March 28, 2011. Construction of the repository began the week of April 4, 2011, and was completed at the end of May. Excavation of mine waste from the upper slope below the mine opening and valley floor areas on the north side of Oljato Mesa began in early June and continues.
2.1.3 Enforcement Activities, Identity of Potentially Responsible Parties (PRPs)
EPA to date has been unable to identify any existing PRPs. EPA will continue to analyze the voluminous responses to the information requests it sent to numerous parties associated with mining in general on the Navajo Reservation. Because of the urgency of this removal, EPA is proceeding with a fund-lead action. EPA will continue to review the information referenced above to determine whether viable and liable parties may be identified, and will pursue recovery of the removal costs if appropriate.
2.1.4 Progress Metrics
There are no progress metrics to report at this time. Off-site disposal is not planned for this removal. Uranium mine wastes at the Site will be transferred to the on-site repository. Total volumes of waste moved into the repository may be reported in future POLREPs.
Waste Stream |
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Quantity |
Manifest # |
Treatment |
Disposal |
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