Richland Uptown Shopping Center Parcel 11

The Richland Uptown Shopping Center Parcel 11 site was originally part of a larger site known as the Richland Uptown Shopping Center. The Uptown Shopping Center, previously owned by the US government, was obtained by private parties in the late 1950s and early 1960s with the development of the shopping center. The City of Richland presently owns the parking lot and service alley encompassing the shopping center.

During a 1993 Phase I Site Assessment, 32 underground storage tanks (USTs) were identified in and adjacent to the service alley; the tanks reportedly stored heating oil. In addition to the USTs, past or present businesses that may have stored or used hazardous materials at the site include print shops, dry cleaners, camera shops, paint stores, and automotive supply stores. The larger site was subsequently split into separate sites based on information indicating separate releases had occurred at different parcels within the larger site.

The Richland Uptown Shopping Center Parcel 11 site is a parcel within the Uptown Shopping Center. The parcel consists of one shop in the mall. In 1994, a heating oil underground storage tank (UST) was removed from the site just outside the rear of the shop. During excavation and tank removal, heavy oil range petroleum hydrocarbons (TPH-O) above Model Toxics Control Act (MTCA) cleanup levels were detected in soil samples. About one inch of free product was seen at the bottom of the tank pit.
 
In 2017, three soil samples were taken from around the former tank pit location and a fourth sample was taken in the City of Richland right-of-way. Heavy oil range petroleum hydrocarbons were detected in two of three soil samples near the former tank pit. Diesel range petroleum hydrocarbons (TPH-D) were detected in the right-of-way soil sample. In addition, TPH-D was detected in a groundwater sample collected at this location at 39,000 micrograms per liter (μg/L). TPH-O was not detected in groundwater, indicating groundwater was not impacted by the former heating oil UST release. Ecology believes the TPH-D contamination is likely to be from the Richland Uptown Shopping Center Parcel 10 site, which is next to and south of Parcel 11.
 
Site cleanup was through natural attenuation. The 2017 soil samples show compliance MTCA Method B cleanup standards that were selected for the site. TPH-O will continue to be reduced as biodegradation further reduces soil concentrations in the future.
 
Ecology has determined the site is no longer a threat to human health and the environment. Ecology made a no further action determination in January 2018.