Not a pit, there was an old silver mine in Shafter that's been productive on and off for centuries. New mining technology and the price of Ag has made it profitable again. Other precious metals are there too including Au.
RGMC has created a new open surface pit on the property to use as feedstock ore until underground mining is safe to commence. The open pit has a lower grade silver than the mine but it still provides valuable silver (and perhaps trace gold) while awaiting opening the old mine up safely. There is an open question on the stockhouse AUN board to whether the underground mine is now open for producing feedstock ore to the ball mills. That was the nature of my question since you drive buy it on a weekly basis I though you might be able to see where the sources of the ore were coming from.
Thanks, Maquanpond, next time I go down there will be first week in December. I will be careful to look for the sources, also, I am keeping an eye on the local newspapers for more news on the mine...Alpine Avalanche, Big Bend Sentinel, etc. Will report back as soon as know anything.