Port of Portland- Terminal 4 Profile

Terminal 4 is a site owned by the Port of Portland on the north side of the Willamette River. Over the years, it has come to be contaminated with a mixture of pesticides, PCBs, metals, and PAHs which are the subject of the early action cleanup.

 

 

Removal Action

 

In 2006 EPA approved the Port of Portland's plan to initiate an early cleanup action, which consisted of two phases.

 

The Port of Portland finished Phase I of the removal action in 2009, which consisted of:
 

Dredging and off­site disposal of sediment from within three areas exhibiting the 
highest chemical concentration at T4.  Specifically, these areas were immediately 
adjacent to Berth 411, adjacent to Pier 5, and north of Berth 414.  A portion of the 
dredge areas identified above could not be designed to achieve the planned removal 
depth due to the concern over slope stability and waterfront structures.  Therefore, 
after completion of dredging, these select areas were covered with a thin layer of 
sand. 
 
Dredging and off­site disposal of contaminated sediment in an area adjacent to Berth 
410 within Slip 3 to support water­dependent maritime use in a manner consistent 
with the Action Memo (USEPA 2006).  Material was removed down to navigational 
depths of between ­39.3 to ­41.3 feet National Geodetic Vertical Datum (NGVD). 
 
Construction of a nearshore cap at the head of Slip 3 in front of and behind the 
existing timber bulkhead to isolate petroleum­contaminated sediment from aquatic 
receptors and control a potential ongoing source to nearby areas. 
 
Stabilization and capping of the Wheeler Bay shoreline to minimize contaminant 
migration to the river. 

 

In June 2009, Port of Portland submitted its Terminal 4 Removal Action Completion Report: Phase I Removal Action to EPA, thus completing Phase I of the removal action.

 

In April 2010, the Port of Portland submitted its Final Phase II Design Status Report (DSR) to EPA for approval.

 

The Design Status Report (DSR) summarizes the status of the Phase II design considering the resolution of technical issues from the 2007 Independent Dispute Resolution (IDR) process with EPA, the progess made in the harbor-wide RI/FS process, and implementation of Phase I activities (see below for details).

 

Currently, the Port of Portland is finishing the final 35% of the design of the CDF.  Implementation and construction of the CDF has been postponed to better reflect and coincide with the Feasibility Study due in November 2011.

 

Below are some conceptual pictures of the CDF planned for Terminal 4 graciously provided by the Port of Portland to aid your understanding.

 

 

 

 

CDF Geotechnical and Structural Design Criteria and Performance Standards:

 

CDF Berm Erosion Protection

     CDF berm designed to withstand ersion from river currents associated with a 100 year flood, wind induced waves

     typical of the T4 site, and propeller wash generated by the size of vessels that typically transit into and out of T4.

 

CDF Berm Static and Seismic Safety

     The CDF shall have a static safety factor of 1.5 or greater and a seismic safety factor of 1.1 or greater.

 

CDF Berm Seismic Event

     The CDF berm deisn seismic event shall correspond to a 10 percent probability of exceedance in 50 years.

 

Capping Lauer (Armor) Erosion Protection

     The armor layer of the caps shall be designed to resist bed shear velocities induced by the largest of 100 year flood

     flow, 100 year waves, vessel induced waves from typical passing vessels, and anticipated propeller wash from vessles

     that operate in the area.

 

All of these Design Criteria and Standards of Performance are "resolved" with the EPA, meaning that the EPA has approved them. 

 

CDF Construction

 

Chemical acceptance criteria for berm fill and verification testing frequency to inform development of chemical criteria for cap and berm fill acceptance.

 

     Partially Unresolved:  Port needs to provide a table of berm fill acceptance criteria.  Verification testing frequency was

     resolved during the April 5, 2007 IDR meeting and includes testing of berm material once per 10,000 cy.

 

Import fill material placed in the CDF must meet same chemical acceptance criteria as established for cap material and berm select fill.  Import material is the material to be placed in the CDF above the saturated zone of contaminated sediment.

 

      Unresolved:  During the May 1, 2007 IDR meeting, USEPA clarified that it is not the intent of the CDF that the import

      fill layer be a disposal facility for contaminated upland soils or contaminated dredged sediments.  USEPA further

      required the Port to show that material being placed in the layer is protective of human health and the environment. 

      Port contends that if material passes for upland disposal, it could be used as fill layer.

 

 

For a complete list of technical documents related to the T4, click here.

 

AttachmentSize
T4_Board1.jpg1.11 MB
T4_Board2.jpg1.26 MB