Published: July 19, 2022 |

[Click image to enlarge]

Denison Mines Corp. has received approval from the Province of Saskatchewan to prepare, construct, and operate the facilities required to carry out the in-situ recovery (ISR) feasibility field test (FFT) planned for the Phoenix deposit at the company’s 95 percent owned Wheeler River project.

The approval was granted by the Saskatchewan Minister of Environment and authorizes Denison to operate pollutant control facilities — which is typical for mining operations and allows for the management of material recovered from mineral extraction through to waste water treatment, discharge, and storage (as applicable). The approval followed the completion of a process involving the review of and consultation on the company’s permit application and supporting materials related to the FFT.

“We are pleased to have received approval from the Province of Saskatchewan to prepare and operate the Phoenix FFT. This is a significant advancement for the FFT, which is a key step in the process of de-risking the proposed Phoenix ISR uranium mining operation and is expected to provide important details to support the ongoing feasibility study,” said Kevin Himbeault, Denison’s vice president of Plant Operations & Regulatory Affairs.

“Overall, Denison was pleased with the permit submission, review, and community consultation process — as it reflected a shared objective of all interested parties to ensure the safe and environmentally responsible operation of the facilities required to complete the FFT,” added Himbeault.

“The permitting of the FFT is an excellent demonstration of our team’s technical and regulatory capabilities. The FFT represents a first-of-its-kind test of a uranium mining method that is new to Canada,” said David Cates, Denison’s president and CEO.

“Successfully navigating the regulatory environment in Saskatchewan to develop conditions for the oversight of a novel advanced field test is a notable accomplishment for both the Denison team and the regulatory team from the Ministry of the Environment,” added Cates.

With receipt of the approval to operate pollutant control facilities from the Minister, preparation and construction of the FFT facilities are now fully authorized and are expected to commence shortly.

The Canadian Nuclear Safety Commission has determined that a nuclear substance license is also required for Denison to possess and store a nuclear substance (mineralized solution containing uranium) resulting from the operation of the FFT. The process to obtain this license is well advanced, and the license is expected to be received before the site preparation and commissioning activities are completed.

FEASIBILITY FIELD TEST

The FFT is designed to use the existing commercial-scale ISR test pattern, installed at Phoenix in 2021, to facilitate a combined assessment of the Phoenix deposit’s hydraulic flow properties with the leaching characteristics that have been assessed through the metallurgical core-leach testing program. Overall, the FFT is intended to provide further verification of the permeability, leachability, and containment parameters needed for the successful application of the ISR mining method at Phoenix and is expected to validate and inform various feasibility study design elements — including the production and remediation profiles expected for the project.

The operation of the FFT is planned to occur in three phases: the leaching phase, the neutralization phase, and the recovered solution management phase.

The majority of the test activities (leaching and neutralization phase) will occur within an estimated 60-day operating time frame, with the construction and placement of temporary facilities commencing approximately two months prior to the commissioning of the test facilities and initiation of the leaching phase.

The leaching phase is designed to assess the effectiveness and efficiency of the leaching process in the mineralized zone, at a depth of approximately 400m below the surface. The recovered solution from the leaching phase is expected to contain dissolved minerals, including uranium, copper, iron, molybdenum, and zinc. Once on surface, the recovered solution (up to a maximum of 500 cubic meters) will be stored temporarily in tanks in accordance with approved environmental protection containment measures.

The neutralization phase includes the recovery of the remainder of the leached mineralized solution from the leaching zone and is intended to verify the efficiency and effectiveness of the process for returning the leaching zone to near baseline conditions. During this phase, a mild alkaline (basic) solution will be injected into the leaching zone to neutralize the area and reverse the residual effects of the acidic solution injected during the leaching phase. The recovered solution from the neutralization phase (up to a further maximum of 500 cubic meters) will also be stored temporarily on surface in tanks in accordance with approved containment measures.

The recovered solution management phase involves separating the solution recovered from both the leaching phase and the neutralization phase into mineralized precipitates and a neutralized treated solution. The mineralized precipitate will be temporarily stored on surface in steel tanks and the neutralized treated solution will be re-injected into a designated subsurface area.

FFT FACILITIES

Temporary surface facilities required to complete the FFT are planned to be installed at the Phoenix site during the third quarter of 2022. The procurement of necessary materials, equipment, and supplies, as well as detailed engineering of the facilities are already well advanced.

The FFT site is planned to include the following facilities and infrastructure:
• Tanker pad: for storage of tanker trucks used for delivery of reagents to site.
• Injection solution preparation module: a modular unit where groundwater will be mixed with reagents to prepare
  the injection solution.
• Test pattern coverall building: a tension-fabric building to be built over the test area.
• Recovered solution surge tank: the surge tank will receive recovered solution from the test wells.
• Solution storage tanks: six tanks are expected to be installed to provide a total of 1,000 cubic metres of solution
  storage.
• Piping: double-walled transfer piping will run from the recovered solution surge tank (next to the test wells) to
  the solution storage tanks.
• Recovered solution management modules: two modular units will be mobilized to site that contain equipment
  for managing the recovered solutions.
• Mineralized precipitate storage tanks: during the recovered solution management phase, the mineralized
  precipitate will be transferred into fully enclosed and lockable storage tanks.
• Laboratory: a mobile laboratory will be located on site and equipped for bench-scale testing of samples.
• Construction/Operations Center: a mobile office will serve as a construction office and operations center as well
  as the main gate entry point for the site.
• Wash car and change room: a mobile facility will allow staff to change and wash before and after each shift at
  the Phoenix site.
• Perimeter fence: the entire area will be fenced and gated to control access and minimize interactions with
  wildlife.

APPROVAL TO OPERATE POLLUTANT CONTROL FACILITIES

Under the terms of the approval to operate pollutant control facilities obtained from the Minister, Denison is authorized to construct and operate various regulated elements associated with the FFT, including pollutant control facilities, mineralized precipitate facilities, radon air pollution abatement equipment, and hazardous substances, and waste dangerous goods storage facilities.

The approval includes specific operating conditions related to (a) mineralized precipitate, recovered solution and drill cuttings, handling, and transportation, (b) hazardous substances material storage, handling, and transportation, (c) air management, (d) water/wastewater management, and (e) waste handling, transportation, and disposal.  Additionally, the approval includes provisions related to inspections, monitoring, reporting, and decommissioning and reclamation.

About Denison Mines
Denison is a uranium exploration and development company with interests focused in the Athabasca Basin region of northern Saskatchewan, Canada. The company has an effective 95 percent interest in its flagship Wheeler River Uranium Project, which is the largest undeveloped uranium project in the infrastructure rich eastern portion of the Athabasca Basin region of northern Saskatchewan. Denison’s interests in Saskatchewan also include a 22.5 percent ownership interest in the McClean Lake joint venture, plus a 25.17 percent interest in the Midwest Main and Midwest A deposits, and a 66.90 percent interest in the Tthe Heldeth Túé, and Huskie deposits on the Waterbury Lake property. Each of Midwest Main, Midwest A, THT and Huskie are located within 20 kilometers of the McClean Lake mill.

To stop by Denison’s website, CLICK HERE

Be in-the-know when you’re on-the-go!

CLICK HERE to register your email address.

Copyright © 2022 Mining Connection LLC. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed without permission.

For licensing permission, .(JavaScript must be enabled to view this email address)