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Environmental Cleanup Site Information (ECSI) Database Site Summary Report - Details for Site ID 5118, H.G. LaVelle Landfill

This report shows data entered as of June 10, 2023 at 4:50:16 PM

This report contains site details, organized into the following sections: 1) Site Photos (appears only if the site has photos); 2) General Site Information; 3) Site Characteristics; 4) Substance Contamination Information; 5) Investigative, Remedial and Administrative Actions; and 6) Site Environmental Controls (i.e., institutional or engineering controls; appears only if DEQ has applied one or more such controls to the site).  A key to certain acronyms and terms used in the report appears at the bottom of the page.

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Environmental Cleanup Site Information (ECSI) Database Site Summary Report - Details for Site ID 5118, H.G. LaVelle Landfill

Site Photos
Click to View Photo Picture Date Caption Size
View Photo 01/10/2017 View of surcharge site work. Surcharge material was placed at the Cohousing Site is now being moved to the future school building. Photo credit: 91 Kb
View Photo 02/10/2017 Photo of Sodo (meditation hall). Photo credit: 405 Kb

General Site Information

Site ID: 5118 Site Name: H.G. LaVelle Landfill CERCLIS No:
Address: SE corner, NE 82nd Ave. and Siskiyou St. Portland 97213
  County: Multnomah Region: Northwest
Other location information: Developed portions of the site include the Asian American Plaza (8200 NE Siskiyou St.) and Dharma Rain Zen Center (8500 NE Siskiyou St.).
Investigation Status: Suspect site requiring further investigation
Brownfield Site: Yes NPL Site: No Orphan Site: No Study Area: No
Property: Twnshp/Range/Sect: 1N , 2E , 28 Tax Lots: 100, 200, 400
  Latitude: 45.5429 deg. Longitude: -122.5765 deg.  Site Size: 27.84 acres
Other Site Names:
  Asian American Plaza
  Dharma Rain Zen Center
  Northwest Zen Sangha
  Capstone Partners

Site Characteristics

General Site Description: The H.G. LaVelle Landfill is located southeast of the intersection of NE 82nd Avenue and NE Siskiyou Street in Portland. The landfill occupies tax lots 100 and 400 and a portion of tax lot 200. The site is a former quarry pit that was excavated to a depth of up to 80 feet. It was subsequently used as a demolition debris landfill, from 1972 until 1982. The landfill, which covers 26 acres, contains approximately 2 million cubic yards of solid waste, including biodegradable waste that has resulted in generation of methane and other landfill gases.

Thirty-four (34) gas monitoring probes (labeled MW-1 thru MW-34) currently surround the landfill, along with separate networks of 25 gas extraction wells (EW-1 thru EW-23, plus EW-16A and EW-16B) and 17 passive vents (PV-1 thru PV-17). Two on-site groundwater monitoring wells (GWMW-1 and -2) and six off-site groundwater monitoring wells (X1 thru X6) are clustered along the north edge of the site.
Site History: Rose City Sand & Gravel Company operated a gravel quarry at this site from at least 1936 until 1972. From 1972 to 1982 LaVelle and Yett, Inc. backfilled the quarry up to 80 feet deep with approximately 2 million cubic yards of demolition debris, operating under the name H.G. LaVelle Solid Waste Landfill. The debris included inert material such as brick, metals and concrete, along with organic matter including plants and wood. Records also indicate that a limited amount of household waste was disposed of at the landfill, contrary to DEQ permit requirements.

A methane gas monitoring and extraction system was installed along the landfill's north and west boundaries in 1979, after DEQ found high levels of methane in residential soils 200 ft north of the landfill. In 2009 the monitoring and extraction system was expanded along the landfill's south boundary. DEQ issued a Solid Waste Disposal Site Closure Permit (#211) for the landfill in November 2011 to PSFM, LP.

In 2004, Asian American Plaza LLC entered into a Prospective Purchaser Agreement with DEQ to purchase and develop tax lot 200. The Plaza (two buildings housing multiple storefronts) was built in 2006.

In 2012 Northwest Zen Sangha, doing business as Dharma Rain Zen Center, entered into a PPA with DEQ to purchase and develop tax lot 100. Construction of Dharma Rain's Householder Refuge and Temple began in 2014. As of the end of 2016 roadways and utilities had been extended onto the property and two buildings had been constructed.

A golf driving range operated on tax lot 400 for an unknown length of time before closing in early 2000. In 2016 Capstone Partners approached DEQ with an interest in entering into a PPA for the purchase and development of tax lot 400.
Contamination Information: (10/25/2018 KPD/VCP) The H.G. LaVelle Landfill operated at this site from 1972 to 1982, filling in a former gravel quarry with approximately 2 million cubic yards of demolition debris. The debris was mostly inert material such as brick, metal and concrete, although some organic debris (wood scraps and vegetation) and household garbage was also included. A methane gas extraction system was installed along the landfill's north and west boundaries in 1979.

In February 2009, after a period of non-compliance, DEQ issued a unilateral order requiring the landfill owner to monitor and evaluate the landfill gas management system. Initial samples collected in April 2009 found methane concentrations up to 59% by volume (pbv) in the gas monitoring probes and up to 21 pbv in the gas extraction wells. Readings over 1.5 pbv are considered potentially hazardous. The monitoring and extraction system was extended along the landfill's south boundary in September 2009.

Soil and soil gas samples were collected from the east half of the landfill in October 2012 and February 2013 as part of an Environmental Site Assessment. Elevated concentrations of PAHs were found in some shallow soil samples. VOCs (from petroleum products and chlorinated solvents) as well as methane were detected in many of the soil gas samples.
Manner and Time of Release: Landfilling of organic wastes (land clearing debris), resulting in decomposition and generation of methane and other gasses.
Hazardous Substances/Waste Types: Methane, petroleum constituents, and chlorinated solvents
Pathways: The soil profile at the site generally consists of about 4-5 feet of fill soil underlain by debris fill (woody organics and construction debris mixed with soil) down to about 80 ft bgs. Groundwater has not been consistently encountered but is expected to be at the bottom of the landfill.
Environmental/Health Threats:
Status of Investigative or Remedial Action: (10/25/2018 KPD/VCP) A methane gas extraction system was installed along the landfill's north and west boundaries in 1979 and expanded along the south boundary in 2009. DEQ issued a Site Closure Permit for the landfill in November 2011 to the landfill owner, PSFM Limited Partnership. The permit requires the permittee to operate and maintain the landfill gas control system and protect the integrity of the landfill cover. Any construction or development proposals must evaluate impacts to the cover and enhance surface drainage and stormwater control, and must obtain DEQ approval before implementation. Designated monitoring probes (MW-1 thru MW-17, MW-22, and MW-29 thru MW-32) must be tested at least once per month, and the permittee must submit an annual report to DEQ documenting all landfill gas monitoring results and operations & maintenance activities. The permit is effective through August 2021.

Asian American Plaza LLC signed a Prospective Purchaser Agreement with DEQ in October 2004 to acquire and develop tax lot 200 in the northwest corner of the landfill. The PPA required AA Plaza to submit its development plans and methane mitigation and monitoring plans to DEQ for review and approval. AA Plaza also agreed to protect and allow access to the existing methane monitoring and extraction systems on the property.

Northwest Zen Sangha, doing business as Dharma Rain Zen Center, signed a PPA with DEQ in October 2012 to acquire and develop tax lot 100, covering the eastern half of the landfill. The PPA required DRZC to implement "landfill gas mitigation measures" while constructing a proposed temple complex (temple, bath house, dormitory, classrooms, and offices) and 30 residential cohousing units at the site. DEQ approved Health & Safety and Soil & Solid Waste Management Plans for the DRZC development in August 2013.

A Progress Report for the DRZC development was completed at the end of 2016. An additional 4-12 inches of clean soils had been added to the site to improve the landfill cap. Stormwater runoff had been redirected to a concrete conveyance ditch on the east site boundary and from there to a series of dry wells in the southeast corner of the site (outside of the landfill footprint). Subsurface utility trenches had been sealed and blocked with trench dams to prevent methane accumulation and migration. Two buildings had been constructed at the site atop four-foot-thick structural mats and either elevated 1-2 feet above the surface or equipped with a sub-slab passive ventilation system to prevent methane accumulation beneath the structures.

An Updated Progress Report for the DRZC development was received in October 2018, describing the addition of two cohousing units (duplexes) to the complex. Both buildings were constructed atop four-foot-thick structural mats and elevated 1-2 feet above the surface to prevent methane accumulation. All of the work at the site has complied with DEQ regulations and best-management practices for methane mitigation.
Data Sources: 1) GeoEngineers "Draft Phase II Environmental Site Assessment" [March 15, 2013].
2) GeoDesign "Soil and Solid Waste Management Plan" [August 1, 2013].
3) GeoDesign "Site-Specific Health and Safety Plan" [August 1, 2013].
4) GeoDesign "Analysis of Brownfield Cleanup Alternatives" [January 6, 2014].
5) GeoDesign "Completion Progress Report" [December 15, 2016].
6) GeoDesign "Updated Completion Progress Report" [October 9, 2018].

Substance Contamination Information

Substance Media Contaminated Concentration Level Date Recorded
BENZENE Air up to 0.86 ug/m3 10/9/2012
BENZENE Other up to 3,200 ug/m3 10/11/2012
BENZO(a)ANTHRACENE Soil up to 5.6 ppm 10/11/2012
BENZO(a)PYRENE Soil up to 8.4 ppm 10/11/2012
BENZO(b)FLUORANTHENE Soil up to 8.9 ppm 10/11/2012
BENZO(k)FLUORANTHENE Soil up to 3.2 ppm 10/11/2012
DIBENZO(a,h)ANTHRACENE Soil up to 1.8 ppm 10/11/2012
DICHLOROBENZENE,1,4- Other up to 220 ug/m3 10/10/2012 11:44:20 AM
ETHYLBENZENE Other up to 31,000 ug/m3 10/11/2012
INDENO(1,2,3-cd)PYRENE Soil up to 5.9 ppm 10/11/2012
METHANE Air up to 12,000 ug/m3 10/9/2012
METHANE Other up to 510,000,000 ug/m3 10/10/2012
TETRACHLOROETHYLENE Other up to 5,300 ug/m3 10/11/2012
TOTAL PETROLEUM HYDROCARBONS (TPH) Other up to 22,000,000 ug/m3 10/11/2012
TRICHLOROETHYLENE Other up to 1,500 ug/m3 10/11/2012
TRIMETHYLBENZENE,1,2,4- Other up to 4,000 ug/m3 10/11/2012
VINYL CHLORIDE Other up to 33 ug/m3 10/10/2012
XYLENEs Other up to 284,000 ug/m3 10/11/2012

Investigative, Remedial and Administrative Actions

Action Start Date Compl. Date Resp. Staff Lead Pgm
REMEDIAL DESIGN  (Primary Action) 07/05/2012   Kevin Dana VCP
View Full Report Showing Action History

Site Environmental Controls

Control Description Begin Date End Date Last Reviewed By Last Review Date
Periodic montioring & reporting, other categories 01/13/2010   Bob Schwarz
  Comments: Methane gas-extraction system.

Key to Certain Acronyms and Terms in this Report:

You may be able to obtain more information about this site by contacting Kevin Dana at the Northwest regional office or via email at If this does not work, you may contact Ximena Cruz Cuevas (503) 229-6811, or via email at or contact the Northwest regional office.