To: Honorable Mayor and Members of Town Council
Through: David L. Corliss, Town Manager
From: Mark Marlowe, P.E., Director of Castle Rock Water
Shawn Griffith, Assistant Director of Operations & EHS of Castle Rock Water
Title
Resolution Approving the First Amendment to The Town of Castle Rock Equipment and Services Acquisition Agreement with Calgon Carbon Corporation for the Installation of Additional Granulated Activated Carbon Filter Media at the Town’s Plum Creek Water Purification Facility [Plum Creek Water Purification Facility in Castle Rock, CO]
Body
________________________________________________________________________________
Executive Summary
Castle Rock Water (CRW) staff requests Town Council approval of a Resolution approving a First Amendment to the services and acquisition agreement with Calgon Carbon (see Attachment A) to replace the specified regenerated media for new or virgin Granulated Activated Carbon (GAC) media for four of the eight gravity filter vessels at the Plum Creek Water Purification Facility (PCWPF), in the additional amount of $35,148 bringing the new total to $648,312, plus a 5% contingency of $32,416, for a total authorization amount of $680,728.
PCWPF is CRW’s advanced treatment plant for purifying reuse water. Reuse water is a key water supply for CRW that will eventually make up approximately 30% of CRW’s total supply. GAC filtration is one of the advanced treatment processes used to purify reuse water. GAC media needs to be replaced or regenerated on a regular cycle, estimated to be every two to three years.
CRW has been monitoring the performance of the existing GAC media and has determined that replacement or regeneration is coming due. Installing virgin media in the first four vessels, rather than the first two vessels, will ensure that the Town takes full advantage of existing Water rights and capture of reuse water by significantly reducing the schedule. Under the original plan, the schedule for full replacement of the GAC media would have carried out until XXXXX. Under this revised plan of replacing four vessels with virgin carbon instead of two, the full project is scheduled to be completed by January 24, 2023. This is beneficial to use of water rights, operations and water quality. It will also shorten the time needed to change the GAC media at the next change out date estimated to be in early 2025.
History of Past Town Council, Boards & Commissions, or Other Discussions
Castle Rock Water staff presented this item to the Castle Rock Water Commission at their meeting held on December 14, 2022, and the Castle Rock Water Commission voted 7 to 0 to recommend Town Council approval of the Resolution as presented.
Discussion
In order to ensure that the Town is able to treat all available reuse water in 2023 to the highest quality, staff would like to increase the amount of virgin GAC media purchased on the front end. The virgin media will now be installed in the first four vessels, rather than the first two vessels, as previously planned. This procedure will significantly shorten the project completion time and have a beneficial impact on the use of our water rights and on water quality. This revised approach will also shorten the project completion timeline for future GAC media change outs since we will have four vessels worth of GAC media ready to go for the next change out.
GAC is a porous adsorption filter media that is extremely useful for removing a variety of synthetic and organic compounds, contaminants, micro-pollutants, disagreeable tastes and odors that are often found in drinking water treatment sources. Depending on filter operating time and contaminant loading, GAC eventually degrades and loses its ability to bind with pollutants, at which time the GAC needs to be replaced and / or regenerated.
In 2021, as part of the new advanced treatment processes (ATP), CRW began using GAC, with the installation of eight gravity filter vessels, each filled with 40,000 pounds of carbon media. Recent testing and calculations show that the media performance is degrading and contaminants are beginning to break through the filters, indicating that the media should be replaced. The ATP design engineering firm, Burns and McDonnell, predicted that the GAC media would last about two to three years, which appears to be correct.
CRW is seeking to participate in Calgon Carbon’s Custom Municipal Reactivated (CMR) program, which revitalizes the spent media for reuse. The updated process requires the removal of the spent media from the first four GAC vessels, which is then replaced with new or virgin F300 GAC media. The spent media from the first four vessels are then transported to Arizona for regeneration. The product is regenerated by baking the media, without oxygen, to temperatures above 1,700 degrees Fahrenheit. At that point, a portion, equaling 20% of virgin GAC, is added to the regenerated batch, to complete the lot. The regenerated CMR media is then transported back to Castle Rock.
Calgon Carbon will then remove the spent media from the final four vessels and replace that media with the recently regenerated CMR media. The CMR turnaround is expected to take five weeks to remove, regenerate, and reinstall the media in four vessels. The entire project is scheduled to be completed by January 24, 2023.
The final CMR load is considered a swing load, that Calgon Carbon will store at their facility in Arizona for use two years later, when the GAC vessel’s media replacement cycle begins again in 2025. The cost for the swing load is not included in this purchase.
|
Load Type |
Volume (lbs.) |
Price |
|
Virgin |
160,000 |
$359,356 |
|
CMR |
160,000 |
$288,956 |
|
Total |
|
$648,312 |
The purchase with Calgon Carbon was conducted through an approved sole source justification, (see Attachment B), as they are the only provider found with the ability to regenerate and store CMR GAC for future replacement.
Budget Impact
Funding for this purchase will come from Water Resources/Plant Operations Division/Repair & Maintenance account which has a current balance of ($88,397). Therefore, a budget transfer from the following two accounts will be necessary:
|
Fund Name |
Account Number |
Budget Transfer Amount |
Account Balance After Transfer |
Cost |
Account Balance after Purchase |
|
CIP Operations & Maintenance |
211-4375-443.40-90 |
$582,163 |
$0.00 |
|
|
|
CIP Water Rights Acquisition |
211-4375-443.75-47 |
$250,057 |
$6,369,943 |
|
|
|
Water Resources Repair & Maintenance Equipment Account |
211-4360-443.40-32 |
$832,220 |
-$88,397 |
$680,728 |
$63,095 |
|
Totals |
|
$832,220 |
|
$680,728 |
|
Staff Recommendation
Staff recommends Town Council approve a first amendment to the services and acquisition agreement with Calgon Carbon to remove and replace the GAC media from eight gravity filter vessels at PCWPF, for the amount of $648,312, plus a 5% contingency of $32,416, for a total authorization amount of $680,728.
Proposed Motion
“I move to approve the Resolution as introduced by title.”
Alternative Motions
“I move to approve the Resolution as introduced by title, with the following conditions: (list conditions).
“I move to continue this item to the Town Council meeting on _____ date to allow additional time to (list information needed).”
Attachments
Attachment A: Resolution
Exhibit 1: Calgon Carbon First Amendment Services & Acquisition Agreement
Attachment B: Calgon Carbon Sole Source Justification