Compliments to Soilvision Systems and to MetSoc who mistakenly call their site Heap Leeching—which is really rather different from Leaching. Compliments are due because these two sites come up before LeachMine in a Google search with keywords “heap leach pad”. Actually the misspelling “leech” is perpetrated by other companies as well—you can easily find them via a Google search with the obvious keywords “heap leech.”

Actually I am not worried about others ranking ahead of this site. What worries me is that at the time I did the search this site was not live and we were still preparing it—Google is so good it got deep into our working files.

Nevertheless, let us take a longer look at the sites ahead of us and learn from them re heap leach pads.

Soilvision promotes the use of the computer code SVFlux in analyzing the performance of heap leach pads. Rather than repeat what they say, I simply repeat one of their pictures—worth a thousand words? (And thank you to them—hope they approve—for the system looks good.)

Met Soc tells us this—interesting but what is has to do with a metallurgical society webpage beats me:

Heap leaching means leaching ores that have been mined, crushed, and transported on impervious pads for leaching by sprinkling and percolation of the solution through the ore. Barrick's Pierina Mine in Peru uses heap leaching to extract gold. Pierina is expected to produce more than 800,000 ounces of gold at a total cash cost of less than $50 per ounce in 1999, making it the world's lowest-cost major gold mine.

The facilities consist of a valley-fill heap leach pad and a conventional Merrill-Crowe gold and silver recovery plant. The ore is stacked in a lined containment area behind a retention dam. A leach solution is applied to the top of the ore and allowed to percolate through the heap. As the solution migrates through the ore, it leaches the gold and silver from the rock and holds it in a solution. The gold-bearing solution ("pregnant solution") is collected at the base of the leach pad in the pore space within the heap. The pregnant solution is pumped to the gold recovery plant where suspended solids are removed and the solution is then treated in a conventional Merrill-Crowe precious metal circuit. The same valley-fill system was successfully used at Barrick's Mercur Mine in Utah.

Actually the more informative site, in my opinion, come someway down the page. It is a powerpoint presentation by Smith Williams Consulting with some fine pictures, cross section, checklist, and data.

My admiration for Google ran out when I checked number 100 on their list of sites for keywords “heap leach pad.” Surprisingly it was the InfoMine page listing suppliers providing products starting with the letter H. How does that happen?

So rather than take your chances with Google, keep coming back to this TechnoMine page to find all you need to know about heap leach pads. And let me know if you think I should write about you, your company, and/or your products. I would be delighted to hear from you.