Project: interstate corridor study

Where: Pacific northwest

Overview

NGI completed a Phase I ESA on an approximate one-mile corridor of interstate highway in the Pacific Northwest. Given the time period since original development and the significant changes to the land, assessment of historical utilization was challenging. However, through extensive research and aerial photograph review, NGI identified past property utilizations consisting of gasoline stations, machine shops, fiberglass boat building, and other property utilizations that were considered recognized environmental conditions. It should be noted that NGI’s assessment was able to identify these prior property utilizations notwithstanding that a prior Phase I ESA by another consulting firm had missed these historic property utilizations. The results of the findings allowed the client to better prepare for contingencies during construction and explained the prior detected presence of heavy oil in geotechnical soil borings.