[OldBlevins]

I'm no chemist and my knowledge is pretty sketchy, but there's one thing we've run across from time to time in our fleet. We've had instances with our tanker trunks where we've used a material with a positive charge, emptied the tank completely, then filled it with another material that had a negative charge. It gelled in the distribution lines and was a mess to clean up. We've found we had to completely clean the tanks and lines out before putting an opposite-charged material in them, even though the amount of material left in the tank was negligible. *Why* this is, I have no clue.