PV modules installed on racking system laying on dirt. Thoughts?

[tcleghorn]

I've seen a type of new racking system where PV modules are installed flat, face-up, in contact with the Earth in order to reduce the cost of the racking system versus a traditional fixed-tilt system and increase the ground coverage ratio (GCR). The modules are held down to the dirt with aircraft cable and concrete blocks. The modules may become submerged and the connectors are regularly submerged. The modules are supposed to be cleaned by some automatic means such as a robot.

Any issues you can think of with this arrangement?