Grey water pouring from underbelly when opening

[wjwheeler]

I have the remote grey and waste tank cables that control the valves in the convenience center.
It has been all I can do to open and close these valves since I bought the unit used several months ago. CW in Chattanooga said it was "normal".
Last Thursday I dumped all the tanks without a problem. Saturday morning I was going to dump the grey water only. When I finally got the valve pulled open, grey water poured from the underbelly and not from the drain. I haven't dropped the insulation to check it. It was still dripping water when I left Sunday afternoon. My concern is the waste water dumping on the ground, if I try to drain it.
Thoughts or suggestions, please.