1980-03-19 Regular Meeting - Laserfiche WebLink

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_• ~ " ~ • ~ ~~ Irtt~aataon~cl AERIAL MAPPING COMPANY ~---~ 8927 International Drive • San Antonio, Texas ?8216 ~' PHONE (512) 826.8681 ~~ %, January 10, 1980 O'Malley and Clay, 9055 Katy Freeway, Houston, Texas Consulting Engineers Suite 103 77024 Attn: Mr. Trowbridge .... ' ry Ref. Topographic Mapping, La Porte, Tex. area and our telephone conversations 2 - 4 & 7 January 1980 Gentlemen: In accordance with referenced telephone conversations, we are furnishing the subsequent proposal to complete topographic map manu- • scripts at a scale of 1" = 100' with 2 foot contours and one foot supple- mentary contours, covering approximately 7000 acres in the La Porte, Texas area as delineated on quad map furnished by you and received at our office on 9 January 1980. These topographic mapping requirements will be accomplished in accordance with our standard procedures to provide . topographic map manuscripts at the indicated scale and contour interval, meeting all criteria for National Map Accuracy Standards. In this connection, we propose to complete aerial photographic coverage with an RC8 Precision Mapping_.camera at a scale of 1" = 500', with 60% FOL and 30% sidelap to provide stereo model coverage of the project area. Subsequent to the completion of these operations, we will initiate field survey requirements to provide necessary horizontal and vertical control for subsequent aerotriangulation procedures. In this con- nection, vertical control points will be establis'ed to provide a minimum of two vertical field points along each flight line not exceeding athree-model span. Horizontal control points will be similarly established along each flight line to provide two points per model not exceeding afour-model span. These data will be accomplished by conventional traverse procedures for the horizontal control and differential levels for the vertical control, uti- lizing one second optical reading theodolites and Hewlett Packard Distance Measuring equipment for the traverse requirements and Ziess self-leveling • levels with Philadelphia rods for the differential leveling requirements.