Portland road and Driveway Acquisition
Ash Creek assisted CalPortland to acquire a portion of the former Portland Road and Driveway rock pit in Clackamas, Oregon. Ash Creek completed the due diligence (Phase I and Phase II environmental site assessments [ESAs]) for this 4.5-acre property comprised of a reclaimed former gravel pit. The site is located adjacent to one of CalPortland’s active concrete batch plants, making the site desirable for expansion of their operations.
The Phase I ESA revealed recognized environmental conditions related to undocumented fill placement and a data gap related to possible methane occurrence. During reclamation, the site received fills containing low-concentrations of polycyclic aromatic hydrocarbons (PAHs) from a cleanup site in Portland, which were to be managed in accordance with Oregon Department of Environmental Quality (DEQ) solid waste permit requirements (e.g., placement above water table, below surface soil) and documented. No placement documentation was available for the mildly contaminated fills or other fills used for reclamation, so a Phase II assessment of
the site was completed.
The Phase II ESA included the following components: (1) surface soil sampling across the site; (2) shallow and deep soil hollow auger soil borings; (3) depth-discrete groundwater sampling; and (4) methane screening. Since little was known about the nature of the fills, the analytical program included petroleum hydrocarbons, PAHs, herbicides and pesticides, and metals. A compositing approach was used to maximize the subsurface characterization and minimize laboratory costs.
The results of the Phase II assessment and risk based screening showed that even though the fill was not placed in accordance with DEQ solid waste requirements, the resulting human health risks were acceptable. CalPortland enrolled in DEQ’s Independent Cleanup Pathway of the voluntary cleanup program and received a No Further Action (NFA) determination, based on the Phase II assessment, and ultimately purchased the property.