Aggregates Manager Digital Magazine
Issue link: http://read.dmtmag.com/i/742224
AGGREGATES MANAGER / November 2016 19 PLANT PROFILE members. Their community meetings provide an opportunity for the plant to both communicate with the local com- munity and to learn about current events and concerns. At one such community meeting, a neighbor informed Zacharis- en that she was bothered by one of the pit's lights during night operations. In response, plant personnel shielded all the pit line lamps so that they only light the areas that are being worked in. That way the neighbors don't see them. The plant has also been very sup- portive of the elementary school in Sunol, both monetarily and through activities, such as participating in the elementary school's Earth Day celebration. Looking to the future Zacharisen explains that approximately 30 to 40 percent of the material coming out of the pit is clay, a waste product. In the past, this material was brought back to the plant, but now most of this material, along with overburden, is used in the pit for reclamation. This allows the plant to have better control of long-term overburden storage. "What we're really lacking right now is a surge pile capacity between the pit and the plant," Zacharisen says. "We have about 45 minutes of storage right now. We basically have enough to empty the pit line onto our surge pile, which we can run through the plant in about 45 minutes. In a couple of years, we plan to have greater surge pile capacity." The plant is looking at approximately 26 years of reserves in the current pit at current production volumes, so it is in pretty good shape. After mining is complete, the pit will be transferred to the San Francisco Water Department to be made into a reservoir, but before that can happen, reclamation work will have to be done. "Roughly 80 percent of the reclama- tion has already been completed," Zach- arisen notes. "We started this pit from scratch, so reclamation and the slope walls have all been done, for the most part, to grade and to design as we're mining. We left the walls a little bit fat, so once we finish the pit, all we'll have left to do for reclamation is to come back and trim the slopes to final design for what the county has called out and for what SFPUC wants for water storage. Then, anything above lake level will have to be hydro seeded. Reclamation here will be easy." AM If you'd like to get better performance and longer wear life out of your dewatering media, Polydeck has a multitude of effective options. Using injection molding technology, we can provide screen panels with openings as small as 0.1mm x 9mm and with integrated surface features like dams and restricted flow bars to control material travel and increase drainage rates. Can your screen media producer offer that? Call us at 1-864-579-4594 or visit polydeckscreen.com/aggregate to find the Polydeck sales representative or dealer in your area. An overland conveyor system carries the raw material from the pit, under Inter- state 680, and to the processing pit on the other side.