58 Pa. Stat. § 9
The owner or operator of any well productive of oil or gas in paying quantities shall have the right to give written notice, to any other owner or operator who may be about to drill or may be drilling a well within one (1) mile of said productive well, that the well about to be drilled or being drilled will penetrate the same sand or strata as that from which said productive well obtains its production, and said owner of the well being drilled or about to be drilled shall case off all water found therein, in case said water cannot be bailed out of the hole while drilling with the use of an extension bailer, after the service of said notice, so as to prevent the entry of said water into the sand or strata from which the oil or gas is obtained in said oil or gas well. No such notice shall be of any effect unless given before the sand to be protected shall have been penetrated by the well about to be drilled or at the time being drilled.
58 P.S. § 9