Grand Street Commons

Updated July 2021

清理工作站信息 | Información del Sitio | Thông Tin Địa Điểm |

Cleanup actions for this site have begun. This cleanup is possible with assistance from Ecology’s affordable housing grant program.

Cleanup actions for this site include:

• Excavating and disposing of PCE-contaminated soil from the northwest portion of the West Block, down to about 30 feet below the surface.
• Treating shallow groundwater contaminated with chlorinated solvent in place using chemical reduction (on the West Block and Rainier Ave S)
• Excavating and disposing of petroleum hydrocarbon-contaminated soil on the East and West Blocks down to about 15 feet below ground surface.
• Treating petroleum hydrocarbon -, and 1,4 dioxane-contaminated shallow groundwater in place on the East and West blocks using chemical oxidation.
• Capping petroleum hydrocarbon-contaminated soil to isolate it beneath a portion of 22nd Ave S.
• Capping cadmium- and lead-contaminated soil at the South Block.
• Monitored natural attenuation of shallow groundwater until proposed cleanup levels are achieved.
• An environmental covenant that restricts soil disturbance and/or prohibit groundwater use until proposed cleanup levels are achieved.

The groundwater treatment injections began in June 2021.

Grand Street Commons, LLC purchased this area to be redeveloped as a transit-oriented mix of affordable and market rate housing near the planned Judkins Park Link Light Rail Station. The development will include approximately 314 units of affordable housing as well as 420 market rate apartments. The redevelopment will include some retail space and underground parking.

Location

The Grand Street Commons site is in the Judkins Park neighborhood of Seattle.  The site consists of 17 King County parcels totaling about 3.3 acres, divided into three areas: the West Block, the East Block, and the South Block (see above figure).

History

The site has been used for manufacturing, commercial dry cleaning and vehicle repair and painting. Over the last several decades, businesses operating there released hazardous substances into soil and groundwater.

Belshaw Brothers, Inc. (BBI) operated a commercial facility that produced bakery and restaurant equipment from 1924-2000’s. The facility included a paint building, welding shop, an on-site foundry used for aluminum parts casting, warehouses, production buildings, and an unpaved parking lot. At least three underground storage tanks (USTs) released petroleum products to the soil that migrated to and impacted shallow groundwater at the site.

The parcel in the northwest corner of West Block was occupied by multiple commercial and light industrial facilities from the early 1950s to the present. Penthouse Drapery Cleaners (Penthouse) occupied this parcel for a commercial dry cleaning operation from the 1980’s through the mid-1990’s. From 1998–2020 Seattle Collision Center, which operated a vehicle repair and painting business, occupied the former Penthouse property. In 2018 Penthouse performed an independent cleanup through Ecology’s Voluntary Cleanup Program (project #NW2278) by conducting an interim action.  Electrical Resistance Heating (ERH) was used to remove some of the chlorinated solvents from soil and groundwater on the West Block.

Contamination

Operations from the drycleaner and manufacturing led to contaminated soil and groundwater in many areas of the site. Some contaminants also released vapors into the air. During the remedial investigation, the following contaminants of concern (COCs) were identified for soil and shallow groundwater at the Site above the state Cleanup levels:

• Soil: Total Petroleum hydrocarbons (TPH) in the gasoline range (TPH-G), diesel-range hydrocarbons (TPH-D), cadmium, lead, and trichloroethene (PCE)
• Groundwater: PCE, trichloroethene (TCE), vinyl chloride (VC), 1,4-dioxane, gasoline range (TPH-G), diesel-range hydrocarbons (TPH-D), benzene, xylenes, and arsenic

These contaminants were found at levels that exceed allowable standards under the state’s cleanup law, the Model Toxics Control Act (MTCA Chapter 70.015D RCW), and therefore must be addressed during the cleanup action. Cis-1,2-dichloroethene was also found in the groundwater, but at concentrations low enough that it does not need to be cleaned up under MTCA.

The Model Toxics Control Act (MTCA; Chapter 70.105D RCW is Washington’s environmental cleanup law). It provides requirements for contaminated site cleanup and sets standards that protect human health and the environment. Ecology enacts the MTCA and oversees cleanups. The MTCA site cleanup process is completed in steps (see graphic below) over a variable timeline.