Rose Creek Tailings Facility, Faro Mine
Yukon Territory, Canada
The Faro Mine start mining massive sulphides in 1960 from an open pit mine to recover zinc and lead. Mining continued under various ownerships until 1996, with the exception of two periods of inactivity from 1981-1986 and 1992-1995. In the late 1990's, Deloitte & Touche assumed management of the site in the capacity of interim receiver.
Up until 1992, tailings were deposited in a series of three side valley and cross valley tailings impoundments in the Rose Creek Valley. These tailings impoundments overlie a highly permeable aquifer system comprised of glacio-fluvial deposits.
As a part of closure planning for the mining complex, Robertson GeoConsultants Inc. completed a water and load balance study to assess the current and future loading of sulphate and zinc to the Rose Creek aquifer and Rose Creek. The results of the study hilighted that a groundwater interception system would be required to protect the water quality downstream of the facility.
In 2005, Robertson GeoConsultants was retained to design a groundwater interception system at the pre-feasability level for the Rose Creek aquifer. Work included (i) a field program, (ii) development of a groundwater flow model; and (iii) pre-feasibility design (including preliminary costing) of a groundwater interception system. The field program consisted of drilling and development of two initial pumping wells and several monitoring wells, followed by pump tests of 1-4 day duration. The information from the pump tests was then used to calibrate a groundwater flow model for the site. The model was used to simulate current conditions and evaluate alternative future (closure) conditions. The information from the modeling was used to develop a preliminary groundwater interception system for the tailings facility.
In addition, RGC has provided these services:
- Development of a water and load balance;
- Supervision of drilling, installation and development of pumping and monitoring wells;
- Design and supervision of multi-day pump tests;
- Development & calibration of a 3D ground water flow model (MODFLOW);
- Development and costing of a preliminary groundwater interception system and management plan