HomeMy WebLinkAbout1.16 5.17.12 CDPHE Accept Mods w Condition.pdfSTATE OF COLOMOO John W. Hickenlooper, Governor Christopher E. Urbina, MD, MPH Executive Director and Chief Medical Officer Dedicated to protecting and improving the health and environment
of the people of Colorado 4300 Cherry Creek Dr. S. laboratory Services Division Denver, Colorado 80246-1530 8100 LOwry Blvd. Phone (303) 692-2000 Denver, Colorado 80230-6928 Located
in Glendale, Colorado (303) 692-3090 http://www.cdphe.state.co.us certified mail 7010 I ~ 70 ?OO"2. 03 40 (ooBS May 17,2012 Mr. Dan Packard GreenBack Produced Water Recovery, LLC 1900
Grant Street, Suite 630 Denver, CO 80203 Colorado Department of Public Health and Environment RECEIVE MAY 2 32012 GARFIELD COUNTY BUIWING & PLANNING Re: Acceptance of Response to Modifications
With Condition for the Construction Quality Assurance Certification Report, Shaeffer Ranch Facility, Garfield County, Colorado Dear Mr. Packard: The Colorado Department of Public Health
and Environment, Ha2ardous Materials and Waste Management Division (the "Division") has reviewed the Responses to Modifications (Responses), as required in our "Final Agency Action:
Approval With Modifications" letter (Approval letter) sent to GreenBack Produced Water Recovery, LLC (GreenBack) dated January 17, 2012. The Responses were prepared on your behalf by
CGRS. On February 27,2012, the Division received a letter from GGRS requesting an extension of time to address the Modifications. The request for additional time was granted by the Division
in a letter to GreenBack dated March 6, 2012. The response to Modification 1 was initially received in our office on March 2,2012. A revision to Modification 1 and the responses to Modifications
2 and 3 were received in our office on April 25, 2012. As you know, the three modifications required by the Division's Approval letter were an attempt to document and clarifY some of
the quality items that were required in the approved Engineering Design and Operations Plan (EDOP), but were not contained in the submitted Certification Report from December 2011. Modifications
1 and 2 required a survey to be performed on the pond floors and embankments, with a full-sized topographic drawing generated from the survey.
From the drawing provided in the Responses, the Division is concerned that Ponds 1 and 2, and possibly Pond 3, do not drain at a minimum 1 % slope toward the southeast corners of each
pond, where the leak detection sump, liquid sensor, and evacuation tubing are located. As you may remember, the slope of the pond floors and sump location and sizing were particular
concerns to the Division during the EDOP approval process. In response to Division concerns, CGRS generated the sump detail shown on Sheet Numbers C6-1 and "Details" in Attachment A
of the EDOP. This is also shown as the "Pond Corner Detail" on Sheet 6 of the full-sized drawings following Attachment M of the approved EDOP. Due to the liner being in-place at the
time the survey was performed on the pond floors, the Division understands that it is possible that the subgrade may have achieved the minimum 1 % slope as designed and approved, however,
the in-place liner may mask the true subgrade contours. Nevertheless, from the submitted as-built drawing, it is not possible to conclude that the grade of the pond floors have been
constructed consistent with the approved design. Modification 3 required that density testing be performed on the pond embankments, an item that was apparently missed during embankment
construction. The results of the density testing are presented in the Responses. The results show that 11 in-place density tests were performed, with the compaction ranging from about
78% to 88% of modified Proctor density (ASTM D 1557). The noted specification on the data sheet provided is a minimum of 90% modified Proctor density. Although the post-construction
compaction testing indicates that the in-place embankment material did not achieve the specified density for any of the tests performed, the Division accepts the opinion of the Certifying
Engineer contained in the April 25, 2012 Responses: the soil density ofthe embankment is acceptable for this application. The Division accepts the Responses, with the following Condition,
as satisfying the requirements of the January 17, 2012 Approval With Modifications letter. Condition: Due to the uncertainty the Division still has with respect to the pond floor grade
and the potential ability of the sump to collect liquid, we require GreenBack to install a series of "wet/dry" wells around the impoundments that would be capable of detecting liquid
leakage should that occur. GreenBack shall submit a plan and schedule to the Division for approval prior to well installation. The plan should consider installing a well for each individual
pond side at appropriate depths. Please provide the wet/dry well installation plan to the Division within 60 days of the receipt of this letter. In closing, the Division is authorized
to bill for its review of technical submittals at $125 per hour, pursuant to Section 1.7 of the Solid Waste Regulations, 6 CCR 1007-2. An invoice for the Division's review of the above
referenced document will be sent under separate cover. 2
Should you have any questions regarding this letter, I may be reached by phone at 303-692-3384 or email atlarry.bruskin@state.co.us. Sincerely, ~JfJb Lawrence 1. Bruskin, P.E. Solid
Waste Permitting Unit Solid Waste and Materials Management Program Hazardous Materials and Waste Management Division cc: Randy Kenyon, CGRS Scott Nuenschwander, CGRS Gale Carmoney, Garfield
County file: sw/gar/sha/2.3 3