You've probably already found one or two benchmarks while doing something else. Now you want to go on your first benchmark hunting trip. Pick about 10 PIDs to look for, preferably fairly close to each other. If you can, pick some that other people have found within the last year or so. This should assure you of a good experience finding benchmarks and prevent you from going home without a find on your first trip.

Before going out on your first benchmark hunting trip, be sure to educate yourself on these basic topics: designation, PID, azimuth, witness post, to-reach, azimuth mark, reference mark. Also look through the list of benchmark hunting equipment to get an idea of what to take along.

For every one of the PIDs you've chosen for your hunting trip, print out every page of the datasheet. Even if you intend to 'go paperless' with your benchmark hunting, it is good to use paper at least on your first trip. On each paper, use a highlighter or other marking method to highlight these things:

These are the most important items in a datasheet. Just before going to each PID's location, review these highlighted items in its datasheet. Making a drawing of what you understand from the geometries of the to-reach statements can sometimes save you a lot of time and false starts.

Be ready to take notes. A very important aspect of mark recovery is to note any changes since the last recovery report and inform the NGS of these changes in your recovery report. Changes in street names, power pole numbers, and changes in which local landmarks should be used and their distance and compass direction toward the station are examples of things to note in a recovery report.

In the case of an intersection station, take a picture of the object. Climbing to the top of it is of no value to a recovery report and should not be attempted.

For other geodetic marks such as disks, rivets, chiseled squares, be sure to take at least two pictures of the mark. One should be a closeup picture of the mark, and the other should be a distant picture of the mark from a few feet away to show how the mark is seen in relation to surrounding objects. In your report, say which compass direction you were facing when you took this distant picture. An in-between picture, called an eye-level view is sometimes useful as a third kind of picture. These are taken within 10 feet or so of the mark to show how it looks when you walk up to it. Pictures taken from the mark, without its being in view are of no value to a recovery report.

In the case of a scaled mark, use your GPS receiver to get its longitude and latitude coordinates. Use the averaging function if your GPS receiver has one. Noting these coordinates in your recovery report's to-reach information will be an improvement over the scaled coordinates.

FirstTime (last edited 2009-03-21 21:03:18 by localhost)