Feasibility Study and Technical Report - Pretivm

INSTRUMENT APPROACH PROCEDURESAn IAP assessment has been undertaken with tentative approach limits established forflights under IFR. The assessment indicates the approach limits will remain quite highand require 3 miles forward visibilityWeather conditions would have to be such that for the approach to be safe, the cloudceiling at the airport would be a minimum of 4,698 ft above the airstrip with a horizontalvisibility of at least 3 miles. The limits for a Category D aircraft (faster and larger) wouldbe 5,038 ft and 3 miles.Accordingly, the east approach could operate in weather with a ceiling of not less than5,838 ft above the airstrip and 3 miles horizontal visibility.For aircraft departures, the site was reviewed for viability and found that due tosurrounding terrain, a standard maximum rate of climb departure is not possible. For anIFR departure, the Visual Climb Area (VCA) limit would be 9,100 ft above the airstrip. Thiswill likely result in Visual Flight Rules (VFR) departures whenever the ceilings are below9,100 ft, but above legal VFR limits.The restrictions on the proposed IAPs will likely result in poor reliability when weatherconditions result in low ceilings or poor visibility. The airlines providing service for theProject should be provided this information to judge the reliability of flights based on acombination of VFR and IFR flights to the site. The airline should also be consulted onwhether they could provide service to a lit runway at night based on the likely IFR limitsand challenges of the surrounding terrain.OBSTACLE LIMITATION SURFACESThe Obstacle Limitation Surfaces (OLS) for this site have been based on utilizing aBeechcraft 1900 aircraft. This does not mean the aerodrome cannot be used by largeraircraft, but operators must be made aware of the limitations of the site and theobstacles they will encounter.The approach from the west (runway 07) encounters a hill which is the primary obstacleto the site. Earthworks will be required to reduce the impacts of the hill on the take-offapproach surface areas. The threshold for runway 07 has been displaced to a position300 m from the end of the runway to reduce the quantity of excavation required at theobstructing hill. This will reduce the landing length for runway 07 but likely notsufficiently to reduce the runway usability.The approach from the east (runway 25) is relatively unobstructed and the threshold willremain at the runway end.Both runway directions will retain the full length for take-offs, which are generally morecritical for runway length.Pretium Resources Inc. 18-47 1291990200-REP-R0012-02Feasibility Study and Technical Report on the BrucejackProject, Stewart, BC