If access is refused, it may be necessary to obtain help from the U.S. Marshall, but if properly handled in advance of the field work, the necessary permission will usually be granted. The fact may be stressed that you are a government official and that your work will be impartial. Emphasize that as a qualified surveyor, you are bound to protect all valid interests, property rights, and evidence. Copies of the claimant’s maps of the property showing the claim boundaries, discovery and other workings and access roads should be obtained from the claimant. The claimant may also have aerial photos which will be helpful in planning the survey. Descriptions of all triangulation stations should be obtained. The plat and field note record of all prior mineral surveys in conflict or adjoining, as well as a copy of the connected sheet should be ordered, if not previously furnished with the survey order. The county records pertaining to surveys and particularly the restoration of section corners should be searched. The county surveyor may be helpful. If the field examination reveals that there are insufficient location corners on the ground to identify the claims, an amended location survey with the resulting amended location certificates and request for an amended order for survey will be necessary. =5–2= Survey Methods: The preliminary field examination will suggest the best method of survey. This will be dictated largely by the nature of the terrain and the amount of timber and brush. Modern methods employing theodolites and electronic distance measuring equipment should be used. Regardless of the method used, the work must be sufficiently checked to assure that errors will be avoided. Most errors occur when adjusting corners to their final position. [Illustration] [Illustration: EXECUTING A MINERAL PATENT SURVEY (Transit and Tape Method) ] =5–3= Executing the Survey: The survey is usually initiated by retracing the boundaries of the location, or tying-in the corners, along with the discovery monuments and discovery points. Readily identified corners of conflicting surveys and section corners should also be tied in. The relative positions of the corners and discovery points are then determined by calculated bearings and distances. If the boundaries are within the statutory length and width (1500 x 600 ft.), the end lines are parallel and the sidelines are within 300 feet on either side of the discovery point, the survey may proceed. If only small corner moves of a foot or so will make the claim conform, an amendment is hardly necessary; otherwise, the corners should be moved and amended location certificates filed. A single claim may be surveyed within the location boundaries, without amendment, as long as the above conditions are met. New discoveries may be necessary, but if intervening rights are suspected, it is better to hold to the original discovery points and stake fractional claims as required.