Project Details

  • Environmental Remediation


Create World/ Shintex Global Investment Holdings




Bellevue, WA

Team Members

Dylan Frazer, LG

Mira Flats Bellevue Environmental Remediation

Landau Associates provided environmental services during construction of the Mira high-rise apartment and condominium complex in Bellevue, WA. After demolition of the former buildings at the property and during excavation for a new below-grade parking garage, construction personnel observed petroleum-impacted soil within the building footprint. Landau’s subsequent site characterization indicated cleanup activities were necessary to address soil, groundwater, and soil vapor impacts at the site. Contaminated soil within the building footprint was excavated as part of the construction project; however, field screening and soil characterization sampling indicated that the release also impacted media outside of the building footprint that required an alternative cleanup approach. Landau supported the owner apply for and coordinate with the Pollution Liability Insurance Agency (PLIA) Heating Oil Technical Assistance Program (HOTAP) to complete cleanup at the site.

The site received a No Further Action determination within 5 months of applying to PLIA’s HOTAP program.

The Challenge

With petroleum-impacted soil present both inside and outside the footprint of the Mira building, Landau was challenged with developing multiple remediation and compliance monitoring approaches to address the contamination.

Our Approach

Landau coordinated with the client and the construction contractor to address the bulk of petroleum-impacted soil at the site by excavation and offsite disposal. Our team then collaborated with the client and HOTAP’s site managers to develop sampling strategies that clearly demonstrated compliance with site cleanup standards. To address the contamination outside the building footprint, Landau collected soil, soil vapor, and indoor air samples, and prepared innovative graphics integrating site photos, GPS coordinates, and building construction plans to clearly illustrate the extents of petroleum-impacted soil and help regulators make quick, well-informed decisions during the cleanup and review process. 

The Solution

To demonstrate compliance with cleanup standards, Landau used non-standard evaluation approaches, including developing a site-specific Model Toxics Control Act Method B cleanup level for total petroleum hydrocarbons (TPH)

and evaluated monitoring data using a statistical approach consistent with Washington State Depart of Ecology guidance. The site received a No Further Act determination in January 2019.

Landau maintained consistent and direct communication with HOTAP project managers to facilitate development of sampling approaches consistent with HOTAP opinions and regulatory requirements, and to maintain a rapid project cadence.