Boundary and Topographic Studies

NORTECH generally purchases its surveying services, but this project was an unusual exception because the actual surveying effort was subservient to the need for environmental observation and evaluation while digging test pits and delineating disturbed site boundaries.

 St. Paul Landfill Closure Assessment & Design, St. Paul, Alaska

NOAA contracted with NORTECH to provide assistance in achieving its mandate to close the un-permitted open dump on Saint Paul Island, Alaska, which included property surveying, determination of locations in UTM format for geographical information system (GIS) development and verification, and determination of the extent of the open dump. Completion of this Task Order allowed NOAA, in conjunction with ADEC, to determine (with agreement of the local native community) the final array of open dump closure and interim partial closure design requirements; on-site extents of NOAA properties at volcanic scoria quarries; and the suitability and extent of NOAA properties at the Blubber Dump for use as contractor work laydown and operational areas.  

Because of this project, NORTECH has developed significant in-house technical expertise in the use of Trimble’s GPS Pathfinder® Pro XRS receiver, laser range finder, data logger and pathfinder software. During this project we used our GPS skills to create real-time sub-meter maps of project locations. The remoteness of the project dictated the setup and operation of a DGPS base station for the collection of correction data. We exported our differentially corrected data to AutoCAD 2000 and created the first on site ground-truthed AutoCAD maps of the Island. The Pathfinder software allowed us to pre-plan our data collection sessions for more productive use of field time by determining satellite availability. We also used it for creating data dictionaries with unique lists of features and attributes, which ensured data integrity, and compatibility with our other software systems. We then used our maps as air photo overlays for immediate on site decision-making such as the precise layout and placement of the new city landfill. GPS mapping was crucial in site characterization and eventual closure at this remote project site. The delays between sampling events meant a non-vegetated site might have 3 feet of grass by the next visit. By importing sample locations from our maps into the data logger we could navigate to the exact location regardless of the site changes. Another unique aspect of St. Paul Island is that most beaches are closed off all summer as seal rookeries. The laser rangefinder was found to be an indispensable tool in allowing objects and areas to be accurately located from a remote location, thus preventing any disturbance of the seals. We also used it to map objects on steep slopes that could not have been accomplished without safety ropes and other gear.