2017-04-11_REPORT - M1977424 (2)

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Logan Wash Mine Annual Report Permit No. M-1977-424 have shown minor (0.07 ft.) amounts of movement. Throughout 2015 minor movement was detected in I of 6 extension stakes. This movement is localized as no movement has been detected in the other extension stakes or survey monuments. Due to deteriorating weather during the May 2016 survey, incomplete observation prevented error analysis of the data. The 2016 survey results from extension stake measurement suggests ongoing localized movement at 2 of the 5 extension stakes. Further measurements in 2017 will evaluate if there is a trend in this movement. Physical observations of the Daylight Bench do not indicate ongoing slope failure. 4.0 Reclamation Activities in 2016 Monitoring activities described in Section 3 are considered activities that contribute to successful overall mine reclamation. Other reclamation activities conducted at the Logan Wash Mine in 2016 are discussed in the following sections. 4.1 Revegetation Maintenance Areas seeded during past revegetation work are self-sustaining; it is anticipated that the irrigation system used during early revegetation will not be used in the future. Yellow sweetclover (Meliotus ofcinalis) was prevalent in the Evaporation Pond area during the spring of 2016. BLM representatives suggested that this plant, considered a weed species, be allowed to remain until fall for wildlife habitat purposes. On November 7"' the sweetclover, which stands as high as 3 feet or more, was reduced by mowing. No other revegetation work (weed removal or mowing) was conducted. Transplanting of the endangered plant species P. debilis is discussed in Section 8. 4.2 Well Abandonment No monitoring wells were abandoned during the reporting period. 5.0 Maintenance Activities Maintenance activities included periodic inspections of mine roads, benches, portals, mine water drainage systems associated with the retorts and general mine workings, as well as the inspection of Evaporation Pond facilities including the pond's liner, security fencing, operation, and leak detection system. Maintenance activities conducted at the mine and Evaporation Pond are summarized in the following sections. 5.1 Mine Maintenance During the reporting period, inspections of the Logan Wash Mine site occurred on a weekly to monthly basis during April, 2016 through March, 2017. The upper mine facilities are were not accessible from December through March due to deep snowpack and poor road conditions. Inspections focused on mine roads, headwalls, portal closures, bench surfaces, dump faces, road conditions, and constructed storm drainage and rip -rap channels. Mine water discharge rates and Evaporation Pond water levels were periodically monitored and recorded (Section 3.2). With the exception of road regrading, no mine maintenance was required during the reporting period. Western Water & Land, Inc. 9