Metro Lake Union, Seattle

The Metro Lake Union site is on the north shore of Lake Union, at 1602 N Northlake Way, Seattle. Starting in 1925, the site was a bulk petroleum fueling terminal. It has three areas: two tax parcels and the public right-of-way (ROW) between the two tax parcels. The two parcels are referred to as the North Yard and the South Yard. The South Yard had a warehouse, two docks, and a railroad spur. The North Yard contained aboveground storage tanks for petroleum products, transfer piping, loading racks, and various small buildings.

In 1999, King County Metro and Chevron entered into a consent decree with Ecology. In 2009, Metro sold the North Yard property to Touchstone NLU. The 2007 prospective purchaser consent decree (PPCD) required a limited cleanup of contaminated soils within the North Yard property line. In 2016, the Touchstone NLU portion of the site was given a No Further Action determination for soils within the North Yard. Ecology determined that the requirements of the 2007 PPCD had been satisfied and the PPCD was dismissed. The 1999 Consent Decree remains in effect for soils outside of the North Yard and groundwater throughout the site.

The 2023 Periodic Review found:

• An updated vapor intrusion assessment is needed to ensure the remedy is protective of building occupants on the North Yard property.
• Groundwater cleanup levels have not been met at the conditional point of compliance for one or more of the last five monitoring events for arsenic (most wells), benzene (well AGI-2), and lead (well MLU-3).
• Trend analysis should be incorporated into future monitoring reports in order to evaluate the performance of the remedy over time. A restoration timeframe should be estimated so it can be determined when/if contingency actions might be necessary (if the remedy is not performing as intended). Wells should be sampled for diesel- and gasoline-range TPH to confirm that these are not contaminants of concern in groundwater, and because groundwater concentrations are used as a compliance metric for the soil remedy.
• The condition and location of well MW-14 should be verified during the next sampling event, and the surface monument of well MW-22 must be repaired.
• Since the Consent Decree and Prospective Purchaser Consent Decree excluded the characterization or cleanup of any potentially contaminated sediments, the selected remedy may not be protective of sediments.

Ecology will review comments received during the comment period. The periodic review will become final if no significant changes are made.