^{Ross Island Sand and Gravel – The Environmental Blog}

Ross Island Sand and Gravel is a major supplier of aggregate in the Portland area. Dictionary.com’s definition for aggregate is any of various loose, particulate materials, as sand, gravel, or pebbles, added to a cementing agent to make concrete, plaster, etc. From the 1920s until the summer of 2001, the company mined and processed sand and gravel from the Willamette River at the site on Ross Island. To meet site reclamation requirements, Ross Island Sand and Gravel began importing fill material in the early 1980s. Some of the material the company obtained from Port of Portland shipyards was determined to be unsuitable for unconfined open water disposal due to the presence of contaminants.

This material was placed lawfully in depressions within the lagoon and covered with clean material creating confined aquatic disposal sites. In 1999, Ross Island Sand and Gravel and DEQ determined that mining activities had extended into one of the capped areas resulting in a breach of a confined cell. Between 1999 and 2002, Ross Island Sand and Gravel and the Port of Portland conducted environmental investigations at the site which identified the following contamination as potentially posing unacceptable risk to human health and the environment:

• Elevated concentrations of zinc and arsenic in surface soil samples collected in the vicinity of the processing plant.
• Polynuclear aromatic hydrocarbons, also known as PAHs, detected in surface soil immediately adjacent to the southern portion of the lagoon at concentrations that could pose a threat to fish and wildlife within the lagoon if soil erodes into the lagoon.
• Contaminated material removed from lagoon disposal cell 5 during mining activities.
• PAHs detected at levels slightly exceeding EPA ambient water quality criteria in a grab groundwater sample collected adjacent to the southern portion of the lagoon.
• Elevated concentrations of PAHs, metals, and polychlorinated biphenyls, also known as PCBs, detected in a limited number of surface sediment samples collected from the southern portion of the lagoon where reclamation filling has occurred and in the vicinity of the recapped breach area.
• Elevated pH detected at several locations along the southern shoreline of the lagoon assumed to result be from concrete waste fill.
• Highly contaminated material present in the five confined disposal cells for material dredged from Port of Portland facilities.

The following is what Ross Island Sand and Gravel has done to address the environmental issues over the years:

• In summer 2000, closed the eastern portion of the settling pond containing contaminated material mined from confined aquatic disposal cell 5 and covered it with clean sediments dredged from the western portion of the settling pond.
• In June and July 2007, removed approximately 900 cubic yards of soil contaminated with metals from the processing plant area; placed the soil in a prepared cell located within the capped former settling pond; and capped the cell with clean soil.
• In summer and fall 2007, installed a variety of erosion control measures in the southern shoreline areas immediately adjacent to the lagoon. Measures included: installing drainage berms, stabilizing slopes, and covering with clean fill.
• In May 2007, sampled groundwater in the southern shoreline area. Contaminant concentrations did not exceed conservative screening levels and DEQ determined no further action for groundwater was necessary.
• Between 2001 and 2010, placed approximately 2,400,000 tons of fill in the lagoon achieving a minimum three-foot cap of clean material over contaminated sediment and further stabilizing slopes adjacent to the southern bench area.

Ross Island Sand and Gravel prepared a long-term monitoring/maintenance and contingency plan for the site addressing each aspect of the cleanup. In addition to regular monitoring and maintaining of the cleanup components, Ross Island will inspect caps and stormwater controls after any extreme events including: seismic events of magnitude six or greater, rainfall exceeding 3.4 inches or greater in a 24-hour period, and Willamette River levels of 18 feet or greater.

Based on evaluation of the actions described above, DEQ has determined that no further action, aside from monitoring, is required at the Ross Island Sand and Gravel site and that Ross Island Sand and Gravel has completed its obligations under DEQ Consent Order No. WMCVC-NWR-99-09.

If you believe that Ross Island Sand and Gravel has done a good job of protecting the environment with their normal business practices then forget about ever reading this post. However, if you feel that they could do a better job of protecting the Willamette River than simply monitoring, let your voice be heard by submitting a comment to the DEQ before September 30th @ 5:00pm, 2011.

Project Manager: Jennifer Sutter
Phone: 503-229-6148
E-mail: Jennifer Sutter (sutter.jennifer@deq.state.or.us)