037-5 Wyo. Code R. § 5-9
a. All proofs of appropriation and beneficial use of ground water must be accompanied by maps in duplicate; one of which must be on good quality tracing linen or equivalent. Original drawings prepared on polyester base films with a minimum thickness of 0.004 inch will be acceptable. This will include Estar, Cronaflex, and Mylar drafting films. Maps accompanying original applications must be neatly drawn in either black waterproof ink or acetate ink which will print clearly. Maps on which pencil, ball-point pen, or ink other than black has been used, will not be acceptable.
b. Maps to accompany enlargement applications or amendments of previous filings may be prepared by securing a duplicate original of the map already on file in the State Engineer's Office, and by making the necessary alterations and additions thereto. Duplicate originals, in order to be acceptable, must be on Mylar, Estar, Cronaflex, or equivalent drafting films with a matte surface designed to accept ink and with a minimum thickness of 0.004 inch.
037-5 Wyo. Code R. § 5-9