AA PAD RECLAMATION PERFORMANCE REVIEW AT BARRICK’S GOLDSTRIKE MINE

摘要

Construction of the AA Pad reclamation was completed in the fallof 2000. Seeding of the ET cover began in the late fall of 2000 andcontinued through May of 2001. On Saturday afternoon, June 1,2002, a large, very localized thunderstorm struck the reclaimed AAPad site. Eyewitnesses present at the time described a dark stormcloud parked above the site for less than half an hour. Average rainfallintensity was measured to be 122 mm (4.8 inches) per hour and peakrainfall intensity was estimated to be 213 mm (8.4 inches) to 259 mm(10.2 inches) per hour. At the time of the storm, the construction wasless than two (2) years old and the vegetation had only a singleseason of growth. The entire period from the end of construction untilthe date of the storm was a drought period with below normalprecipitation. Other than a few small snowmelt events, there was noprecipitation event large enough to produce any significant flow in thechannel network. Therefore, the very first significant runoff event wasthe extreme event of June 1, 2002. The storm essentially representsa large-scale field test of the design concepts used at the AA Pad site.Shortly after the storm, data was collected and analyzed with theintent of learning as much as possible about the performance of thecover system design with the expectation that the newly acquiredknowledge might be utilized in future designs to further improve theperformance of similar cover systems during extreme events.