Former Armstrong World Industries Investigation and Remediation (Upland Operable Unit)

The Armstrong World Industries site in St. Helens, Oregon, was historically used to manufacture wood products, ceiling tiles, and insulation beginning in the 1920s. During its use, the site became impacted with heavy metals, dioxins/furans, and polycyclic aromatic hydrocarbons (PAHs).

In 2010, Armstrong World Industries and the two other responsible parties began working under an Order on Consent with the Oregon Department of Environmental Quality (DEQ) in accordance with the agency’s Voluntary Cleanup Program to address contamination at the upland operable unit. GSI’s team of engineers, scientists, and geologists provided crucial technical support to help guide Armstrong World Industries successfully through the upland remedial investigation/feasibility study (RI/FS), design and implementation of the upland remedy, and site closure processes.

GSI began implementing the preferred alternative from the RI/FS in 2018. This remedial alternative, which GSI designed, was completed in two phases. Phase 1 included hot spot excavation, sludge pond and clarifier decommissioning, and development of a stormwater swale system. Phase 2 included the capping and grading of the remediated areas. All active remediation work was completed in 2019.

In response to the implementation of the remedial alternative, DEQ issued a No Further Action determination for the upland operable unit in 2020. GSI has since continued to monitor and evaluate the performance of the upland remedy.

GSI’s work involved:

• Collecting and evaluating key environmental data, which was stored and maintained the data in an accessible environmental database.
• Designing and implementing a cost-effective remedy.
• Helping achieve a No Further Action determination from DEQ.
• Providing ongoing monitoring and reevaluation of the remedy performance.