The installation contractor who installed our facility's 1MW solar system apparently didn't have any U-bolt grounding clamps or acorn clamps large enough to terminate the large copper GEC's to their ground rods. So instead he attached a water pipe bonding clamp to the ground rod, then screwed on an aluminum lay-in lug to connect the GEC. I believe this is an NEC violation because this combination of parts is not L&L for this application. Am I correct?