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Ross Island


Site summary

The site is located on the Willamette River (at river mile 15), about one mile south of downtown Portland. It includes several islands surrounding a lagoon. Ross Island Sand and Gravel Co. mined gravel from the lagoon between 1926 and 2001. Since 1979, the company has been required to place fill (sediment, soil, concrete and other materials) at the site to reclaim upland, wetlands and in-water areas that were previously mined and return them to a more natural state. Reclamation goals were established in the 2002 Reclamation Plan. Former operations and some of the early imported fill resulted in contamination at the site that the DEQ cleanup program is managing. In 2003, DEQ established numerical screening values, measurements of contamination that are used to evaluate whether fill is suitable for placement in uplands or the lagoon. Prior to placement, all fill must be tested to confirm that is does not contain chemicals at levels that could result in harm to the humans or wildlife that use the site. DEQ's work is coordinated with several other agencies involved at Ross Island Lagoon.

To find out more, visit our Frequently Asked Questions page.

Updated Class A In-Water Screening Criteria

In January 2021, DEQ began the process of updating the chemical screening values used to evaluate what imported fill can be placed at the site (see more information in the FAQs below). The existing screening values had not been updated since 2003 and many of the values were outdated. These updates were completed in April 2022 and incorporated into DSL's removal-fill permit which DSL issued for public comment in August 2022. Comments requested that only “Class A" fill, the “cleanest" fill, be accepted by RISG. The new “Class A" in-water screening criteria ensure that decisions about fill placement are based on the best available science and consistent with regional dredged material evaluations for protection of human health and the environment. 

View the 2022 Ross Island Fill Evaluation Fact Sheet for information on the new “Class A" in-water screening criteria and guidance on the sampling and chemical analyses required to characterized material proposed for use as reclamation fill at Ross Island.

Additional information

RISG continues to place fill at Ross Island Lagoon to meet reclamation objectives. In May 2023, Oregon Department of State Lands approved modifications to RISGs existing removal-fill permit for reclamation of Ross Island Lagoon. The modifications included:
  • A completion deadline of 2033 for removal-fill activities
  • Increased bond requirements to ensure reclamation is completed
  • Approval of RISGs 2022 Adaptive Management Plan which reduces the amount of fill and time required for reclamation while adding additional habitat
  • DEQ's latest screening criteria for in-water fill placement.
  • Installation of new signage upon completion of reclamation to support public awareness of fish and wildlife habitat
View RISG's modified removal-fill permit for more information.

​DEQ approved the water quality certification for Ross Island Sand and Gravel on Oct. 13, 2022. This is related to but separate from the Oregon Department of State Land's removal-fill permit for reclamation, which includes DEQ's updated screening criteria for fill used in filling in the lagoon. This certification references the removal-fill permit to determine what is allowable clean fill in order to protect water quality.

On Dec. 12, 2022, DEQ received a petition for reconsideration for the water quality certification from the Portland Audubon Society, Human Access Project, Northwest Environmental Defense Center and Willamette Riverkeeper. DEQ denied this request for petition on Feb. 9, 2023 and responded to the petitioners in a formal letter.

Project contacts

Sarah Greenfield  
Project Manager  

Cleanup: Sarah Greenfield, DEQ Cleanup Program

Portland Sediment Evaluation Team: James Holm, U.S. Army Corps of Engineers

Harmful Algal Blooms: Oregon Health Authority

Water Quality: Jeff Brittain, DEQ 401 Water Quality Program

Your DEQ Online Project Number: 2409