HomeMy WebLinkAbout980261.tiff STAT F OLORADO
Roy Romer,Governor - ' of Coto
Patti Shwayder,Executive Director `°ti,
Dedicated to protecting and improving the health and environment of the people t4d9 qc O
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HAZARDOUS MATERIALS AND WASTE MANAGEMENT DIVISION •' •
http://www.cdphe.state.co.us/hm/ 1e7G
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4300 Cherry Creek Dr.S. 222 S.6th Street,Room 232
Denver,Colorado 80246-1530 Grand Junction,Colorado 81501-2768 ( fl f k Colorado Deparunent
Phone(303)692-3300 Phone(970)248-7164 of Public Health
Fax(303)759-5355 Fax(970)248-7198 and Environment
January 21, 1998 Certified Letter No. P 335 550 971
Mike Cervi
Northern Colorado Brine
P.O. Box 169
Sterling, Colorado 80751
RE: Financial Assurance Cost Basis - Northern Colorado Brine
Dear Mr. Cervi:
The Solid Waste Unit of the Hazardous Materials and Waste
Management Division (the Division) has reviewed the Financial
Assurance Cost Basis (FACB) for the above referenced facility
located in Weld County. The FACB is dated December 16, 1997 and
was prepared by Mr. Gene Fritzler. On Friday, January 9 , 1998
Glenn Mallory and Roger Doak of the Division and Trevor Jiricek
of Weld County Health Department met to discuss the cost
estimates and information described in the FACB. Our comments
below pertain only to the cost estimates, not the financial
assurance mechanism.
The document categorized the cost estimates into four phases: (1)
Pre-closure Screening and Evaluation, (2) Demolition, Remediation
and Disposal, (3) Costs for Permanent Covers and (4) Post-closure
Care Cost Estimates. Comments on each phase are discussed below.
Pre-closure Screening and Evaluation
1. The proposed soil characterization of ponds C, D and E will
include six boreholes per pond. Ponds A and B will be screened
using four boreholes per impoundment. The Plan indicates that
metal soil samples will be taken at three (3) inches and six (6)
inches for all ponds. We believe soil screening for metals
should be sampled from surface to six inches and six inches to
twelve inches. Samples taken from these intervals are more
representative of site conditions.
2 . If analytical results show contamination at the base of the
liner, then a minimum of one borehole per pond will be completed
to bedrock or groundwater, whichever occurs first. This will
demonstrate the vertical impact, if any, to soils beneath the
ponds. One sample should be collected and analyzed from each
"deep" borehole in the horizon demonstrating the highest degree
of contamination, based upon PID screening or some other field
screening mechanism. u.52 506
�f� .` (E J. CA 980261
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Mike Cervi
January 21, 1998
Page 2
3 . Although this document provides some specific information on
the proposed soil characterization, a comprehensive sampling and
analyses plan must be submitted to the Division and the County
for review and approval prior to sampling.
4 . Table I-A lists soil constituents which will be analyzed for
during the site screening process. The following parameters:
benzene, toluene, ethylbenzene, xylene (BTEX) , oil & grease,
sodium, chloride and sulfate, are associated with E&P waste and
shall be included in the screening phase.
5. Table I-B lists the proposed cleanup target levels for soil
and groundwater. If an impact to groundwater has occurred,
contaminant concentrations shall not exceed those standards
pursuant to "The Basic Standards for Ground Water" 5 CCR 1002-41.
A determination of the acceptable levels for onsite soil
contaminants will not be made until the site investigation phase
is completed and the data is evaluated by both the Division and
the County. Also, for comparison purposes and to determine
acceptable levels for soil contaminants, the FACB should be
amended to include the collection and analysis of a background
soil sample.
6 . Pursuant to Section 9 . 10 of the solid waste regulations 6 CCR
1007-2 , residual sludge shall be analyzed for hazardous
characteristics. Accordingly, representative sludge samples from
individual ponds shall be submitted for TCLP analyses of RCRA
metals and volatile organic compounds. The cost for the
additional analytical tests must be amended to the FACB.
7 . It appears that Table I-C provides cost estimates for only
Pond C characterization. Cost estimates shall also be provided
for ponds A, B, D, and E.
8 . According to this section and the facility's design and
operations plan, the ponds will be returned to their original
grades. During the construction of pond E, a significant amount
of soil was moved onto the property. Additional soil may have
also been brought in during the construction of ponds A, B, C,
and D. A soil balance should be conducted to determine the
volume of soil which may have to be removed from the site. The
cost estimate should be amended to reflect the removal of this
soil.
Demolition, Remediation and Disposal
9 . It appears that Table I-D lists cost estimates for only Pond C
remediation and disposal. Cost estimates shall also be provided
for ponds A, B, D, and E.
Mike Cervi
January 21, 1998
Page 3
10. It does not appear that the cost for transporting
contaminated material to a disposal facility is provided. Cost
estimates for transportation must be included.
11. Total volume of sludge contained in Pond C is given as
1, 400cy in the text and 1, 000cy in the cost estimate for Table I-
D. Please clarify.
12 . One of the proposed remediation methods would involve
landfarming the contaminated soils. Again, only cost estimates
are given for Pond C bioremediation. Cost estimates shall also
be provided for ponds A, B, D, and E. Prior to implementation of
this treatment method, a detailed bioremediation plan, including
a treatability study, must be submitted to both the Division and
the County for review and approval.
13 . You've indicated that a detailed investigation plan for the
underdrain is forthcoming. However, cost estimates for the
investigation were not included. Please provide the cost
estimates.
14. Pursuant to Section 2 . 4 . 3 of the facility's design and
operations Plan, "All improvements at the site will be removed
including tanks, ponds and access road." Accordingly, monies
must be included in the cost estimates for closure activities to
remove all equipment from the site, transportation to and
disposal at a sanitary landfill.
Costs for Permanent Covers
15. The proposed cover system would utilize the current soil
liner has the infiltration layer. Any portion of the soil liner
used for the cover is contingent upon our evaluation of the
analytical data from the soil liner investigation. If the soils
associated with the liner are removed and/or remediated to
acceptable levels, a constructed cover may not be necessary.
16. In accordance with Section 2 . 4 . 5 of the facility's design and
operations plan, ". . .all improvements and waste including salt
contaminated soil will be removed from the site. Nothing will
remain that could cause water pollution after closure."
Acceptable concentrations to remain onsite for salt contaminated
soil, including the soil liner, will be evaluated upon completion
of the soil and groundwater investigation.
Post-Closure Care Costs
17 . The post-closure period as required per the facility's USR
permit, is two (2) years. All post-closure costs are based
Mike Cervi
January 21, 1998
Page 4
a two-year period. This appears to be a relatively short post-
closure period, however, if the soil cleanup goals are achieved
and groundwater has not been impacted, then two years seems
reasonable.
18 . Although the facility's permit specifies a two year post-
closure period, in accordance with Section 3 . 6. 3 (B) of the
Regulations, the length of the post-closure care period may be
increased if it is determined that the lengthened period is
necessary to protect human health and the environment.
General Comments
19 . The ponds are surrounded by an underdrain which is accessed
by eight (8) observation manholes not monitoring wells as stated
in this document. According to the facility's design and
operations plan, ". . .there is no existing groundwater beneath the
site other than that which might exist below the Pierre Shale. . ."
Groundwater was not encountered during the construction of the
underdrain. However, site conditions have changed as evident by
the presence of water in the underdrain. Both the Department and
the County have previously requested an investigation as to the
source of the water. To date, we have not received a plan or
proposal for an investigation.
20. According to this document, NCB is pursuing the option of
locating an injection well at the facility as a possible disposal
method for brine waters that remain onsite. We have not received
any information regarding the injection well. The installation
and operation of an' injection well on this property is not
pertinent to the closure and post-closure care of the facility.
As a result, we recommend that all references to the injection
well be deleted from the plan.
21. We were informed by Weld County that the CD and USR for this
facility expire during 1998 . Please be aware, if the County does
not renew your permit, pursuant to the Section 3 . 5 of the
Regulations, closure activities must commence within thirty (30)
days of the nonrenewal date and would need to be completed within
180 days from this date.
22 . Section V, Project Schedule, provides time lines for site
assessment activities. The time periods proposed to complete
many of the task assignments (e.g. , historical record evaluation-
7 months, site characterization-16 months, evaluate existing
operating ponds-10 months, and evaluate inactive ponds-16 months)
are not appropriate. As indicated in comment #21, closure
activities must be completed within 180 days from the date of
closure. Given this, the time lines must be revised to fit into
this time frame.
Mike Cervi
January 21, 1998
Page 5
We are requesting that a comprehensive response to the above
comments be submitted to the Division and county within thirty
(30) days of receipt of this letter. We believe that thirty days
is reasonable because many of the tasks, according to the site
assessment time lines, should have commenced during September of
1997.
In addition, we are requesting that an underdrain investigation
plan be submitted within thirty (30) days of receipt of this
letter. We are concerned about the existence of water in the
underdrain, particularly because the original facility design and
operations plan states that shallow groundwater does not exist
beneath this site. The investigation plan will include the
installation of a minimum of three (3) groundwater monitoring
wells (one upgradient and two downgradient) at the facility's
property boundary. The monitoring wells are necessary to
evaluate the site hydrology, geology and to determine if
groundwater quality has been impacted by onsite activities.
Further, a review of our files indicates that Weld County has
requested this plan on numerous previous occasions, including but
not limited to letters dated November 14 , 1996, May 1, 1996,
February 28, 1997 , May 22 , 1997, and July 16, 1997. However, we
have yet to receive any plans or proposal concerning the
determination of the origin of the water in the underdrain.
Failure to meet the thirty-day deadline, as describe above, will
result in the Department making a formal request to the Weld
County Board of Commissioners to initiate the revocation process.
This concludes our comments regarding the Financial Assurance
Coat Basis for the Northern Colorado Brine Facility. Comments on
the financial assurance mechanism, if necessary, will be
submitted under separate cover.
Sincerely,
Roger Doak
Geologist
Solid Waste Unit
Compliance Program
cc: Weld County Board of Commissioners
Trevor Jiricek, Weld County Health Department
Gene Fritzler
Monica Sheets, AGO
sw/wld/nor le
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