(a) The authorized officer will accept and approve any application (if otherwise regular), to make a non-mineral entry of the residue of any original lot or legal subdivision which is invaded by mining claims if the tract has already been lotted to exclude such claims. If not so lotted, and if the original lot or legal subdivision is invaded by patented mining claims, or by mining claims covered by pending applications for patent which the non-mineral applicant does not desire to contest, or by approved mining claims of established mineral character, the authorized officer will accept and approve the application (if otherwise regular), exclusive of the conflict with the mining claims.
(b) The authorized officer will allow no non-mineral application for any portion of an original lot or 40-acre legal subdivision, where the tract has not been lotted to show the reduced area by reason of approved surveys of mining claims for which applications for patent have not been filed, until the non-mineral applicant submits a satisfactory showing that such surveyed claims are in fact mineral in character. Applications to have lands which are asserted to be mineral, or mining locations, segregated by survey with a view to the non-mineral appropriation of the remainder, will be made to the authorized officer of the proper office. Such applications must be supported by a written statement of the party in interest, duly corroborated by two or more disinterested persons, or by such other or further evidence as may be required, that the land sought to be segregated as mineral is in fact mineral in character.