"I would like to emphasize that permission to carry out either kind of testing would be exceedingly helpful."

This sentence made me think immediately "Oh, she plans to dig the holes whether or not I give my permission, she's just saying that my permission would make her life easier."

In addition to the comments others have left I really think this needs to be reworded in order to make it clear that you wouldn't do anything without their permission and if they would give you their permission that would be very much appreciated.