Nah, I don't like it. You should re-write the entire sentence. It just doesn't read well, doesn't make much sense. What are the "requirements"..? It's fine from "I am sending this letter"... then... it just falls apart. Start again after "this letter" and state exactly what it is you're trying to say in a more simple, clear, and complete manner.
ALlBangedup is right. I have been an English teacher and I can assure you that your sentence makes no since.Think about what you are trying to say and be clear and direct with your sentence. Example: I am sending this letter to inquire about restrictions regarding vehicles at the dam sites.