CENEX Supply & Marketing Inc Rinsate

Facility Site ID: 33599645 Cleanup Site ID: 370

  • Site Status

  • Construction Complete-Performance Monitoring

Public Comment Period October 31, 2022-November 29, 2022

Draft Periodic Review Report

Ecology invites you to review and comment on the draft periodic review report for this cleanup site. We conduct a periodic review at least every five years after beginning cleanup at a site. The purpose of the review is to evaluate current site conditions and to ensure the continued protection of people and the environment.

In October 2022, we completed the second periodic review and recommended the following actions be completed during the next five years:

  • Continue monitoring groundwater at the site
  • Sample the domestic water supply well southeast of the West Canal
  • Continue optimizing the multisparge and soil vapor extraction systems, which treat contaminants in groundwater and soil gas
  • Complete an evaluation of the remediation performance before the next periodic review
  • Amend the Cleanup Action Plan to include the adjustments to site cleanup levels based on revised practical quantitation limits
Review the draft report
  • Periodic Review
  • Ecology's Eastern Regional Office: 4601 N. Monroe St., Spokane, WA. Please call 509-329-3415 to make an appointment.​​​​​​
Submit comments via email, mail, or online by 11/29 to:

Kristin Beck, kristin.beck@ecy.wa.gov
4601 N. Monroe St., Spokane, WA 99205
Online comment form

Next steps

Ecology will review comments received during the comment period. The periodic review will become final if no significant changes are made due to public comment. An additional public comment period will be held if significant changes are made. We will hold an online public meeting if 10 people request it.

Site Background

The CENEX Supply & Marketing, Inc. (CENEX), Rinsate site stored and distributed liquid fertilizer and soil fumigant at 300 Division Street in Quincy. The fertilizer and fumigant plant was built in 1974 and operated until 1991. Operational features included an equipment rinse pad, a rinsate storage pond to capture contaminated liquids from rinsing equipment, and fumigant storage tank areas.

The site is in a commercial/industrial area next to a major rail corridor. Quincy High School is about 500 feet southwest of the site. A mobile home trailer park and other residences are about 1,000 feet south and southeast of the site.

Water for area businesses, schools and residents is provided by the City of Quincy public water supply system.

Contamination

The liquid fumigants stored at the plant contained volatile organic compounds (VOCs), the primary contaminants found in soil and groundwater at the site.

Cleanup

The contaminated groundwater plume is outlined in red.
The contaminated groundwater plume is outlined in red.

During the early 1980s, fumigant releases were reported. Site investigations found areas where soil and groundwater contamination exceeded state standards and posed a risk to humans and the environment.

CENEX conducted several cleanup actions in the early 1990s. Between August 1994 and February 1995, all former fumigant storage tanks were decontaminated and removed. In 1997, soil from the rinsate pond was removed, and the area was covered with a thin layer of gravel. Monitoring wells were installed on the plant property and in offsite areas to evaluate groundwater contamination. Monitoring results confirmed a contaminated groundwater plume about 0.5 miles long. The plume runs to the southeast and passes beneath a portion of the Quincy High School property. Studies conducted in the late 1990s and early 2000s found no vapor concerns to the school from the plume.

In 1998, Ecology and CENEX signed an Agreed Order, requiring CENEX to:
  • Develop plans for a cleanup system to remove contaminants from soil 
  • Further investigate the extent and location of groundwater contamination and propose cleanup options 
Temporary soil and groundwater treatment systems were put in place in 2001 to protect humans and the environment while the final cleanup action was determined. 
 
In 2001, Ecology and CENEX signed a Consent Decree, requiring CENEX to: 
  • Contain contaminated soil with asphalt caps 
  • Capture VOCs in soil with a soil vapor extraction system 
  • Treat VOC vapors with a biofiltration system 
  • Treat groundwater with oxygenation by microsparging and air stripping 
  • Monitor groundwater to evaluate cleanup performance and effectiveness 
  • Prevent public exposure to contaminated groundwater 
Periodic reviews 
In October 2022, we completed the second periodic review and recommended the following actions be completed during the next five years:
  • Continue monitoring groundwater at the site
  • Sample the domestic water supply well southeast of the West Canal
  • Continue optimizing the multisparge and soil vapor extraction systems, which treat contaminants in groundwater and soil gas
  • Complete an evaluation of the remediation performance before the next periodic review
  • Amend the Cleanup Action Plan to include the adjustments to site cleanup levels based on revised practical quantitation limits
Ecology conducted the first periodic review in September 2008 and made the following recommendations: 
  • Monitoring well network upgrades and repairs 
  • Residential well sampling 
  • Ditch surface water sampling 
  • Enhanced groundwater plume mapping 
  • Remediation system assessment, upgrades and repairs 
  • Lab analyses to assess ongoing biological degradation processes 
  • Development of environmental covenants with affected property owners to record existing contamination and ensure any future owners will know of its existence
Legal 3
Document Title Document Date Document Type
Cenex Supply and Marketing Order Entering CD 3/6/2001 Consent Decree
Cenex Supply and Marketing CD 12/14/2000 Consent Decree
Cenex Supply and Marketing AO Remedial Action 6/25/1998 Agreed Order
Public Information 5
Technical Reports 4
Document Title Document Date Document Type
Second Periodic Review: CENEX Supply & Marketing Inc. Rinsate 10/21/2022 Periodic Review (5 Year)
Don Low Domestic Well Groundwater Sampling, Ecology Approval of Work Plan 6/17/2014 Site Specific Technical Document - other
Periodic Review 2009 Response Actions, Ecology Satisfaction Letter 2/13/2014 Site Specific Administrative Document - other (Administrative correspondence)
Cenex Supply and Marketing Periodic Review 9/1/2008 Periodic Review (5 Year)
There may be more documents related to this site. To obtain documents not available electronically, you will need to make a public records request.

Places to see print documents

  • Eastern Regional Office
    N 4601 Monroe St
    Spokane, 99205-1265
    Please schedule an appointment to view print documents at this location.

Contaminants 3

Contaminant Type
Soil
Groundwater
Surface Water
Air
Sediment
Bedrock
Halogenated Organics - Halogenated Organics C
Non-Halogenated Organics - Petroleum Products-Unspecified C
Pesticides - Pesticides-Unspecified C C
S
Suspected
C
Confirmed Above Cleanup Levels
B
Below Cleanup Levels
RA
Remediated-Above
RB
Remediated-Below
R
Remediated
This contaminant list was based on our best information at the time it was entered. It may not reflect current conditions at the site.