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After a desired number of scenarios are produced, route analysts compare GISPRO reports and their detailed summary statistics that include length, elevation profile, crossing counts, vegetation density, terrain conditions and rock characterization. To complete the analysis, engineers enter GISPRO outputs into proprietary cost-estimation and hydraulic software (see Figure 2). Getting Results GISPRO’s first test came early in 2009, when CPL engi- neers performed a traditional analysis and compared results against a corresponding GISPRO run. “This was a unique opportunity in that the engineer for the proj- ect had already performed the routing analysis manu- ally, enabling us to measure the time-savings benefit of GISPRO,” notes Jensen. Using a combination of topographic basemaps and Google Earth Pro, the mostly manual method took three days to produce three scenarios of varying lengths for a combined total distance of 220 miles. In contrast, GISPRO made quick work of the pipeline relocation project and completed the analysis in four hours—nearly seven times faster. GISPRO proved itself faster and comparable to manual delineations, but also “yielded more compre- hensive information,” adds Jensen. Another useful feature of the tool is the wider cor- ridor analysis (see Figure 3). Based on percentages from the LCP output, corridors allow analysts to see fingers of opportunity beyond a single path. “You get optimized corridors that enable engineers to understand the flexibility of various routes within a corridor, and the location of ‘pinch-points’ which restrict route flexibility,” says Jensen. For greater confidence, the engineers carefully stud- ied the quality of the three GISPRO routes and corridor outputs to determine their validity. Minor discrepan- cies were found among analyses, but each manually delineated route fell inside the GISPRO corridor. By the end of the exercise, GISPRO-generated alignments were chosen and submitted—unedited—to the client. Using this GISPRO reference case alone, extrapolating “time to complete” and “length of project” demon- strates effort savings measured in weeks to months for the longest pipeline projects. Building Useful Models Early computer scientists appropriately coined the expression “garbage in, garbage out.” With that in mind, the accuracy of GISPRO, or any analysis, depends on the accuracy of its underlying source information. Thus far, most GISPRO projects use a Chevron-hosted aggre- gate of best-available and subscription-based world datasets. Pre-feasibility studies targeting plus/minus 50 percent cost estimates, as is with most GISPRO Figure 4. Three pipeline-route alternatives are draped across a DEM and satellite image. After generating an LCP alignment, 3-D GIS tools allow stakeholders to visualize terrain as well as explore and validate paths of multiple alternatives. projects, can accept more-granular datasets than proj- ects entering feasibility and design stages (i.e., cost estimates of 25 percent and 10 percent). Equally prudent for building useful models is inclusive collaboration. Leveraging the broadest cross section of stakeholders should produce an ample array of expertise, opinions and attitudes necessary for making better design decisions and reducing infrastructures’ natural impacts. Not limited to pipelines, but inherent to all cross- country infrastructure projects, are their footprints across physical and cultural geographies. Potentially adverse impacts are one reason why infrastructure projects’ opponents outweigh proponents 20:1 for the most-loathed pipeline plans (Day, 1998). However, when responsibly designed, built and main- tained, most recognize infrastructure as a net benefit and necessary part of society. For the impoverished, they’re a welcome improvement to their quality of life. References Day, N.B., ed. 1998. Pipeline Route Selection for Rural and Cross-Country Pipelines, American Society of Civil Engineers Publishing. Goodland, R. 2005. Oil and Gas Pipelines Social and Environmental Impact Assessment: State of the Art; www.goodlandrobert.com/PipelinesBK.pdf. International Energy Outlook. 2010. U.S. Energy Information Administration; www.eia.doe.gov/oiaf/ieo. Geoff Price is an HES One Call Specialist, DOT Pipeline Safety & Compliance Assurance Team, Chevron Pipe Line Co.; e-mail: geoffprice@chevron.com. M AY 2O11 / WWW . GEOPLA CE . COM 25