DWQ-2024-006915

Donald Stidd
Environmental Manager
American Pacific Corporation (AMPAC)
10622 West 6400 North
Cedar City, Utah 84720
Dear Mr. Stidd:Subject:Construction Permitfor the WECCO Evaporation Pond #2
On April 17, 2024, the Division of Water Quality (DWQ)received the engineering plans and specifications WECCO Evaporation Pond #2. The initial Pond #2 design was for a single High-Density
Polyethylene (HDPE) liner. This was then changed to a double HDPE liner with leak detection. The final engineering plans were submitted on September 17, 2024. The engineering plans
and specificationswere prepared by GEM Engineering and stamped by Utah Certified Professional Engineer (P.E.) Robert W. Corry P.E. Wheeler P.E.
AMPAC has a Ground Water Discharge Permit No. UGW210002 (Permit). This Permit was for the regulation of the Azide pond. The WECCO Evaporation Pond #1 was not covered under that Permit.
An Amended Permit is being issued to regulate the Azide Pond and the WECCO Evaporation Ponds #1 and #2. The Construction Permit for the WECCO Evaporation Pond #2 is included as Appendix
A of the Amended Permit.The following is a summary of the proposed major construction projects:
A new Evaporation Pond #2 that will and have two HDPE liners with a leak detection system.The plans and specifications, as submitted, comply with the Utah Water Quality Rules, (R317,
Utah Administrative Code). A Construction Permit is hereby issued as constituted by this letter, subject to the following conditions:Any revisions or modifications to the approved plans
and specifications must be submitted to DWQ for review and approval, before construction or implementation thereof. Please submit any changes for review and approval directly to Woodrow
Campbell, P.E., of the DWQ Ground Water Protection Section.A written operations and maintenance manual, containing a description of the functioning of the facilities, an outline of routine
maintenance procedures, and all checklists and maintenance logs needed for proper operation of the system, must be submitted and approved before the final inspection and operation of
the system.The approved facilities must not be placed in service unless DWQ has conducted a final inspection, reviewed and approved the As-Built Construction Certification Report, and
provided written authorization to place the constructed facilities in service.Construction activities that disturb one acre or more are required to obtain coverage under the Utah Pollutant
Discharge Elimination System (UPDES) Storm Water General Permit for Construction Activities. The permit requires the development of a storm water pollution prevention plan (SWPPP) to
be implemented and updated from the commencement of any soil disturbing activities at the site until final stabilization of the project. For more information, or to obtain permit coverage
on-line, please go to: http://www. waterquality. utah.gov/UPDES/stormwater. htm
The plans and specifications for this project have been stamped and signed by a Professional Engineer currently licensed to practice in the state of Utah. The construction design, inspection
supervision, and written construction certification of all work associated with this Construction Permit must be performed by a Professional Engineer licensed to practice in the state
of Utah.
This Construction Permit will expire one year from the date of its issuance, as evidenced by the date of this letter, unless substantial progress is made in constructing the approved
facilities or the plans and specifications have been resubmitted and the construction permit is reissued. This permit does not relieve you, in any way, of your obligations to comply
with other applicable local requirements. You may contact Jeremy Roberts, Southwest Utah Public Health Department at 435-986-2582 or Paul WrightDEQ District Engineer at 435-896-2590
for further assistance regarding local matters.
Please contact Mr. Campbell at the beginning of construction to allow periodic inspections to be scheduled. Upon completion of the project, a final inspection and approval of the As-Built
Construction Certification Report is required before the approval to operate the completed facilities can be issued. Please remain in contact with Mr. Campbell to schedule the final
inspection. The Construction Certification Report with final as-built drawings must include test results for the following construction quality assurance and quality control (CQA/QC)
elements:
Soil Subgrade
Proctor Curves,
Soil Classification,
Field Compaction Testing, and
Subgrade Acceptance Certification.
Flexible Membrane Liner
Panel Placement Log,
Trial Seam Test Log,
Seaming Record,
Seam Test Record,
Repair Log,
As-Built Drawing,
Manufactures Certification including QA/QC Testing of the Rolls, and
Professional Engineer Certification.
If we can be of further assistance, please contact Mr. Woodrow Campbell at [e-mail] or [phone].
Sincerely,
John Mackey, P.E.
DirectorJKM/WWC/DJH:Attachments (2):WECCO Pond 2 Plans Rev 3 (DWQ-2024-006588)WECCO Pond 2 Specs (DWQ-2024-005072)cc:w/o AttachmentsPaul Wright, DEQ District EngineerJeremy Roberts,
Southwest Utah Public Health Department Robert Corry, GEM Engineering, Inc. ([e-mail])