Status of Investigative or Remedial Action:

(6/3/03 JAK/VCP) Washington County entered the Voluntary Cleanup Program (VCP) in June 2003.



(8/25/03 JAK/C&ER) A final Remedial Investigation (RI) and Feasibility Study (FS) report was submitted on September 24, 2003. A Voluntary Agreement between DEQ and Washington County to complete Remedial Investigations (RI) and FS study work became effective on July 24, 2003.



(8/22/06 JAK/VCP) DEQ issued a Record of Decision (ROD) for the site on 2/25/04 requiring methane gas mitigation controls as part of site development. DEQ entered into a Consent Order 6/24/04 with Washington Co. and Bridgeport Village to implement the ROD. Remedial design of methane mitigation measures was completed in December 2004. Installation of methane mitigation measures was initiated in October 2004 and substantially completed in October 2005. Operation and maintenance and site monitoring are ongoing.



[The following is an article in the �Building on Brownfields� newsletter, May 2007]:



Institutional controls give new life to former landfill



After tackling such tenacious problems as methane contamination, developers that turned a former landfill into a major retail and office development in Tualatin, Ore., are happy to see the project is experiencing less stressful troubles. �The problem people have now is it�s so successful, that parking is very tight down there,� Bruce Wood, president of Foundation Real Estate Development, says of Bridgeport Village. Wood previously worked for the company that developed Bridgeport Village. With advances in technology and cleanup methods, former landfills are becoming more attractive as redevelopment projects. Bridgeport Village is one example of what can be done with such land.



Only 10 miles south of Portland, Bridgeport Village is described as a premier outdoor shopping, eating and entertainment experience in Oregon. The 478,000-square-foot development, which also includes a four-story parking garage, sits on 29 acres. It was the 10th largest retail development in the country when it opened, Wood says.



Built on the former Durham Quarry, the site was purchased by Washington County in the early 1950s to use as a gravel quarrying operation. In the late 1970s, the county hired a contractor to fill up the 90-foot deep quarry with clean fill, such as construction and demolition waste. However, organic plant materials and wood waste from construction sites also made their way into the landfill. The decomposition of organic materials produces methane. While the gas is a naturally occurring compound, too much of it can cause health problems or even an explosion.



The high levels of methane found during the Phase I and II environmental site assessments came as a surprise, raising much concern among developers as well as the public, Wood says. Dealing with this issue delayed the project by a year, and increased the cost by about $5 million. The project cost about $100 million.

To deal with the methane, engineering and institutional controls were put in place:

� An active gas extraction system was placed around portions of the interior and perimeter of the site at various depths to suck out the methane on the property.

� A passive sub-slab venting system and a low permeability gas membrane were installed beneath each building slab. The thick membrane is made of impermeable plastic.

� Low permeability membrane collars or trench plugs were installed for every utility that enters or exits each building or crosses a site boundary.

� Interior gas sensors and monitors were installed on buildings and closed areas that aren�t ventilated. No sensors have ever gone off, Wood says.

� An ongoing process of monitoring will continue until the methane levels are at acceptable levels.



The project, which was started in 2000 and did not fully open until May 2005, had many hurdles, including finding ways to structurally support buildings sitting on 90 feet of unstructured fill. But three years of good planning is one reason for its success, Wood says. The people involved in this project had to be creative and stay on track. Public and private entities also worked hard at cooperating and reaching decisions quickly.



�It�s an example of a public-private partnership that went really well,� Wood says. The outcome is a major bonus for the surrounding community. About $8.5 million in off-site improvements were made as a result of the project, $14 million was paid to the county for the land, the development is expected to generate $4 to $5 million annually in property taxes alone and hundreds of jobs were created. On top of all this, a blighted site that sat between two cities was cleaned up and reborn into a signature destination for the area. �It�s hard to put a dollar number on that,� Wood says. *End of article.*



(05/23/13 EKM/VCP) Site monitoring and reporting is ongoing. DEQ conducts periodic reviews to ensure the selected remedy remains protective. DEQ approved an Updated Methane Monitoring and Contingency Plan, dated April 27, 2012. In addition, DEQ continues to review any construction remodels and associated documentation to ensure integrity of vapor mitigation engineering controls.