Class Location & Gathering Type Verification Utilizing the IntegrityMap HCA Gas Tool

Altamira completed a new geographic information system (GIS) based Class Location, HCA and moderate consequence area (MCA) analysis for the facility’s transmission system, which consisted of a 6-mile, 8-inch fuel gas pipeline and a 1-mile, 10-inch ethylene gas pipeline. Altamira performed the work using its proprietary IntegrityMap HCA tool, which combines Class Location, gathering and HCA analysis in a single platform. For transmission systems such as this one, IntegrityMap HCA produces Class Location, HCA and MCA results. For gathering systems, the same platform also evaluates gathering classifications using consistent pipeline attributes and spatial inputs.

For this project, the team updated the measured centerlines, structures, pipe diameter, maximum allowable operating pressure (MAOP), building occupancy and Identified Site attributes. IntegrityMap HCA then modeled potential impact radius (PIR) buffers, applied the sliding-mile analysis and evaluated the transmission requirements under 49 CFR Part 192. The ethylene analysis used the product-specific PIR factor for flammable gases other than natural gas.

Rather than relying solely on historic site classifications, Altamira independently revalidated the existing Identified Site inventory. During that review, a GIS analyst contacted two of the previously identified sites to confirm occupancy conditions, and a field technician visited one location for additional verification. The remaining Identified Sites continued to be included, while the review established that these two properties no longer met the Identified Site criteria. Altamira reran the analysis using current conditions, documented the Class, HCA and MCA event stationing, and delivered both the final reports and supporting GIS data so the operator retained a traceable technical record of the findings.