1980-03-19 Regular Meeting - Laserfiche WebLink

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• • O'Malley and Clay -page 2 - January 10, 1980 Houston, Texas Traverse requirements for this project will emanate from and tie to _ monumented stations in the area, provided such stations exist. Otherwise, these traverse requirements will be completed as closed loops to provide an unadjusted closure not to exceed 1:15, 000. Level lines will emanate from and tie to established BM's to provide a minimum of third order closures. Subsequent to the completion of these field survey operations, we will prepare film diapositives from the original aerial photography and will drill-mark, with our Wild Pug Instrument, a minimum of six points per model, together with the photo-identifiable field control on these dia- positives. These data will be measured on a Mann Comparator interfaced with an Autotrol Digitizer and an IBM Keypunch to provide necessary infor- mation for reduction of these control data by fully analytical aerotriangula- tion requirements, utilizing the US Coast and Geodetic Survey Reduction Program. These adjusted data will provide the indicated minimum of six horizontal and vertical points for each stereo model to be utilized in scaling and leveling these data for t'ne subsequent compilation of topographic mapping information on B8S and/or Kelsh Plotters. In connection with the indicated contour interval, this mapping project is designed to provide a two foot contour interval to meet National Map Accuracy Standards. Except along • embankments, drains and similar type features where contours will be closely spaced, we will compile intermediate contours at one foot intervals. These intermediate contours will be depicted by a dash symbol on the final manu- scripts. Manuscripts will contain a 500 foot grid on the State Plane Coor- dinate System, if possible, or on an assumed datum in the event monumented horizontal control stations are not located within the area of mapping opera- tions. Manuscripts will be prepared to contain approximately three stereo models each, with an overall image area on each manuscript of approximately 32" x 54". Manuscripts will be finalized in pencil and will be photo-reprodu- cible for re-formatting into standard sheets by conventional photographic procedures if desired. All planimetric detail visible in the aerial photography and compatible with the final scale of 1" = 100' will be shown on these manu- scripts with conventional map symbolization. In connection with the time frame for completing these requirements, we will schedule the aerial photographic operations immediately upon the • receipt of your notice to proceed and would expect to complete these opera- tions within eig'it to ten days, and we will require a total of approximately