The insulator dump is located at the Jackrabbit Exit 269 on I40 in Arizona. The owner of the gift shop owns the dump site and charges $3 for all you keep. While it is impossible to know what is under the crossarm piles there are some fairly good CREBs and Mclaughlins in the mix. Parts of very good color beehives are visible so there are likely other gems to be found. Watch for the rattlesnakes in warm weather and good luck.