HomeMy WebLinkAboutMT DEQ (2) - -. I a . 'c"
C ta Department of � ® �1�) ICJ '`'`• 1 I Brian Schweitzer, Governor
P.O. Box 200901 • Helena, MT 59620 -0901 • (406) 444 -2544 • www.deq.mt.gov
April 22, 2010 - -- ..�
Iii l C , G VI lS
Greg Brown ;
Refinery EH &S Manager
CHS Inc. A PR 2 6 2010
P.O. Box 909
Laurel, MT 59044 -0909 CI T Y OF LA JREL
Kenneth E. Olson, Jr.
Mayor, City of Laurel
P.O. Box 10
Laurel, MT 59044
Subject: Discovery of Oil Film in Groundwater at the City of Laurel Wastewater Treatment
Plant, Laurel, Montana
Dear Mr. Brown and Mr. Olson:
On March 31, 2010, the City of Laurel reported to the Department of Environmental Quality
(Department) that an oily film on groundwater had been discovered in a test pit on the site of the City's
wastewater treatment plant and in excavations on adjacent property owned by CHS Inc. The oily film
was found during preparations for installation of a water line from the City's water plant to the
wastewater treatment plant.
The City of Laurel and CHS have worked together to coordinate treatment and disposal of
contaminated groundwater and oily film during dewatering of the excavation. The Department
appreciates these efforts. While contaminated groundwater produced during dewatering is being
adequately managed, the nature and source of the contamination must also be addressed.
Investigations on the Laurel Refinery property have shown contamination on groundwater up- gradient
of the City of Laurel wastewater treatment plant. As required by the CHS Laurel Refinery hazardous
waste permit (MTHWP- 02 -02), CHS must institute corrective action as necessary to protect human
health and the environment from all releases of hazardous waste or hazardous constituents at the
facility. This requirement includes implementing corrective action beyond the facility boundary for
any releases which may have originated from the refinery. Therefore, CHS must conduct an
investigation to determine whether the contamination discovered on the City's property originated at
the refinery. If so, CHS must institute corrective measures to address the contamination. CHS must
also determine the nature and extent of the contamination found on -site during the water line
installation and take the necessary corrective measures to ensure no off -site migration of the
contamination occurs.
Enforcement Division • Permitting & Compliance Division • Planning, Prevention & Assistance Division • Remediation Division
R. Nissen
K. Olson
April 22, 2010
Page 2 of 2
At this point in time, the source or sources of contamination is unclear. Therefore, the City of Laurel
must ensure that possible releases from the wastewater treatment plant are not a contributing factor to
the groundwater contamination. Should it be determined that the contamination originated all or in
part from releases from activities on the City of Laurel property, then the City will be required to
initiate corrective measures.
The Department encourages CHS and the City of Laurel to cooperate in characterizing the
contamination and determining the potential source or sources. Decisions on how best to address
remediation of the contamination can be made once the nature and extent of the contamination is
determined. If the contamination poses an immediate threat, remedial steps must be taken immediately
to prevent exposures to human or ecological receptors, and prevent migration of contaminants into
surface water.
By May 31, 2010, please submit a report detailing actions taken to date and how CHS and the City of
Laurel plan to move forward in addressing the contamination. The two parties may choose to submit a
combined report or two separate reports.
If you need assistance or have any questions, please do not hesitate to contact me. My phone number
is 406/444 -2876 and my email address is listed below.
Sincerely,
Rebecca Holmes
Environmental Science Specialist
Waste and Underground Tank Management Bureau
Permitting and Compliance Division
e -mail: rholmes @mt.gov
cc: Chad Anderson, DEQ Enforcement Division
Ron Nissen, CHS Inc., P.O. Box 909, Laurel, MT 59044 -0909
Kurt Markegard, City of Laurel, P.O. Box 10, Laurel MT 59044
HW facility files: CHS Laurel Refinery — Spills #1