Denison Announces Decision to Advance Wheeler River to Feasibility Study Stage and Selection of Wood Plc as Independent Lead Author
Denison Mines Corp.
1100 – 40 University Ave
Toronto, ON M5J 1T1
www.denisonmines.com
PRESS RELEASE
DENISON ANNOUNCES DECISION TO ADVANCE WHEELER RIVER
TO FEASIBILITY STUDY STAGE AND SELECTION OF
WOOD PLC AS INDEPENDENT LEAD AUTHOR
Toronto, ON –Sept 22, 2021. Denison Mines Corp. (“Denison” or the “Company”) (TSX: DML, NYSE
American: DNN) is pleased to announce that the Wheeler River Joint Venture (“WRJV”) has approved the
initiation of an independent Feasibility Study (“FS” or the “Study”) for the In-Situ Recovery (“ISR”) mining
operation proposed for the Phoenix uranium deposit (“Pho enix” or the “Project”). The Company is also
pleased to announce the selection of leading global consulting and engineering firm Wood PLC (“Wood”)
to lead and author the FS in accordance with Canadian Securities National Instrument 43-101
(“NI 43-101”).
David Cates, Denison’s President & CEO, commented, “The ISR de-risking activities we’ve completed
since the publication of the Pre-Feasibility Stud y (‘PFS’) for Wheeler River in 2018 have been
designed to support the completion of a future Feasibility Study, and the results to date have further
confirmed the technical viability of the Project – leading to the decision to advance the Project and
initiate the formal Feasibility Study process.
During this de-risking phase, we have been able to verify ore-body permeability and the leachability
of high-grade uranium in conditions representative of an ISR mining setting. We’ve also engineered
an improved containment design using a more conventional ground freezing approach. Based on
the results of field programs and metallurgical lab testing completed over the last three years, we
are confident that the Project is ready to advance into a full Feasibility Study. Taken together with
the selection of globally recognized engineering firm Wood, the decision to launch the formal
Feasibility Study process for Phoenix represents another important step towards achieving our
objective of bringing low-cost ISR mining to the high-grade uranium deposits of the
Athabasca Basin.”
Feasibility Study
The completion of the FS is a critical step in the progression of the Project and is intended to advance de-
risking efforts to the point where the Company and the WRJV will be able to make a definitive development
decision. Key objectives of the Study are expected to include:
Environmental Stewardship: Extensive planning and technical work undertaken as part of the
ongoing Environmental Assessment (“EA”), including applicable feedback from consultation efforts
with various interested parties, is expected to be incorporated into the FS project designs to support
our aspiration of achieving a superior standar d of environmental stewardship that meets and
exceeds the anticipated environmental expectations of regulators and aligns with the interests of
local Indigenous communities;
Updated Estimate of Mineral Resources: Mineral resources for Phoenix were last estimated in
2018. Since then, additional drilling has been completed in and around the Phoenix deposit as part
of various ISR field tests, including drill hole GWR-045 (22.0% eU 3O8 over 8.6 metres, see news
release dated July 29, 2021), and exploration drilling. The updated mineral resource estimate will
form the basis for mine planning in the FS;
Mine Design Optimization: FS mine design is expected to reflect the decision to adopt a freeze
wall configuration for containment of the ISR well field (see news release dated December 1, 2020),
as well as the results from multiple field te st programs and extensiv e hydrogeological modelling
exercises, which have provided various opportunities to optimize other elements of the Project –
including well pattern designs, permeability enhancement strategies, and both construction and
production schedules;
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Processing Plant Optimization: FS process plant design is expected to reflect the decision to
increase the ISR mining uranium head-grade to 15 g/L (see news release dated August 4, 2021),
as well as the results from extensive metallurg ical laboratory studies designed to optimize the
mineral processing aspects of the Project; and
Class 3 Capital Cost Estimate: The FS is also intended to provide the level of engineering design
necessary to support a Class 3 capital cost estimate (AACE international standard with an accuracy
of -15% /+25%), which is expected to provide a basis to confirm the economic potential of the
Project highlighted in the PFS completed in 2018 (see news release dated September 24, 2018).
Wood PLC
Wood is a global leader in consulting and engineering across energy and the built environment, helping to
unlock solutions to some of the world’s most critical challenges. Wood provides consulting, project and
operational solutions in more than 60 countries an d employs around 40,000 people. Importantly, Wood’s
Saskatchewan-based team has sign ificant experience in ISR mining projects as well as large-scale
uranium, potash and solution mining projects. For more information about Wood, please visit
www.woodplc.com.
About Wheeler River
Wheeler River is the largest undeveloped uranium projec t in the infrastructure rich eastern portion of the
Athabasca Basin region, in northern Saskatchewan – including combined Indicated Mineral Resources of
132.1 million pounds U3O8 (1,809,000 tonnes at an average grade of 3.3% U 3O8), plus combined Inferred
Mineral Resources of 3.0 million pounds U 3O8 (82,000 tonnes at an average grade of 1.7% U 3O8). The
project is host to the high-grade Phoenix and Gryphon uranium deposits, discovered by Denison in 2008
and 2014, respectively, and is a joint venture betwe en Denison (operator) and JCU (Canada) Exploration
Company Limited. Denison has an effective 95% owners hip interest in Wheeler River (90% directly, and
5% indirectly through a 50% ownership in JCU).
A PFS was completed for Wheeler River in 2018, cons idering the potential economic merit of developing
the Phoenix deposit as an ISR operat ion and the Gryphon deposit as a conventional underground mining
operation. Taken together, the project is estimated to have mine production of 109.4 million pounds U3O8
over a 14-year mine life, with a base case pre-tax NPV of $1.31 billion (8% discount rate), Internal Rate of
Return ("IRR") of 38.7%, and initial pre-production capital expenditures of $322.5 million. The Phoenix ISR
operation is estimated to have a stand-alone base case pre-tax NPV of $930.4 million (8% discount rate),
IRR of 43.3%, initial pre-production capital expendi tures of $322.5 million, and industry leading average
operating costs of US$3.33/lb U3O8. The PFS is prepared on a project (100% ownership) and pre-tax basis,
as each of the partners to the Wheeler River Joint Venture are subject to different tax and other obligations.
Further details regarding the PFS, including additional scientific and technical information, as well as after-
tax results attributable to Denison's ownership intere st, are described in greater detail in the NI 43-101
Technical Report titled "Pre-feasibility Study for the Wheeler River Uranium Project, Saskatchewan,
Canada" dated October 30, 2018 with an effective date of September 24, 2018. A copy of this report is
available on Denison's website and under its prof ile on SEDAR at www.sedar.com and on EDGAR at
www.sec.gov/edgar.shtml.
Denison suspended certain activities at Wheeler River during 2020, including the EA process, which is on
the critical path to achieving the project development schedule outlined in the PFS. While the EA process
has resumed, the Company is not currently able to estimate the impact to the project development schedule
outlined in the PFS, and users are cautioned against re lying on the estimates provided therein regarding
the start of pre-production activities in 2021 and first production in 2024.
About Denison
Denison is a uranium exploration and development company with interests focused in the Athabasca Basin
region of northern Saskatchewan, Canada. In addition to its effective 95% interest in the Wheeler River
project, Denison's interests in the Athabasca Basin include a 22.5% ownership interest in the McClean
Lake joint venture, which includes several uraniu m deposits and the McClean Lake uranium mill that is
contracted to process the ore fr om the Cigar Lake mine under a to ll milling agreement, plus a 25.17%
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interest in the Midwest Main and Midwest A deposits, and a 66.90% interest in the Tthe Heldeth Túé ("THT,"
formerly J Zone) and Huskie deposits on the Waterbury Lake property. The Midwest Main, Midwest A, THT
and Huskie deposits are each located within 20 kilometres of the McClean Lake mill.
Through its 50% ownership of JCU, Denison holds additional interests in various uranium project joint
ventures in Canada, including the Millennium project (JCU 30.099%), the Kiggavik project (JCU 33.8123%)
and Christie Lake (JCU 34.4508%).
Denison is also engaged in mine decommissioning and environmental services through its Closed Mines
group (formerly Denison Environmental Services), which mana ges Denison's Elliot Lake reclamation
projects and provides post-closure mine care and ma intenance services to a variety of industry and
government clients.
For more information, please contact
David Cates (416) 979-1991 ext 362
President and Chief Executive Officer
Shae Frosst (416) 979-1991 ext 228
Investor Relations
Follow Denison on Twitter @DenisonMinesCo
Qualified Persons
The technical information contained in this re lease has been reviewed and approved by Mr. David
Bronkhorst, P.Eng, Denison's Vice President, Operat ions and Mr. Andrew Yackul ic, P. Geo., Denison's
Director, Exploration, who are Qualified Persons in accordance with the requirements of NI 43-101.
Cautionary Statement Regarding Forward-Looking Statements
Certain information contained in this news release constitutes ‘forward-looking information’, within the meaning of the applicable United
States and Canadian legislation, concerning the business, operations and financial performance and condition of Denison.
Generally, these forward-looking statements c an be identified by the use of forward-look ing terminology such as ‘plans’, ‘expects’,
‘budget’, ‘scheduled’, ‘estimates’, ‘forecasts’, ‘intends’, ‘anticipates’, or ‘believes’, or the negatives and/or variations of such words and
phrases, or state that certain actions, events or results ‘may’, ‘could’, ‘would’, ‘might’ or ‘will be taken’, ‘occur’, ‘be achieved’ or ‘has
the potential to’.
In particular, this news release contains forward-looking information pertaining to the following: initiation of the FS; the se lection and
appointment of Wood to author the FS; the planned scope, element s, and objectives of the FS, including the plans for an updated
mineral resource estimate, mine design optimization processing plant optimization and Class 3 capital cost estimate; other evaluation
activities, objectives and expectations, including the ongoing EA and related processes; the results of the PFS and expectations with
respect thereto, including the designs di sclosed to-date and the ability to maintain or build upon such designs;; other develop ment
and expansion plans and objectives; and expectations regarding its joint venture ow nership interests and the continuity of its
agreements with its partners and third parties.
Forward looking statements are based on the opinions and estimates of management as of the date such statements are made, and
they are subject to known and unknown risks, uncertainties and other factors that may c ause the actual results, level of activi ty,
performance or achievements of Denison to be materially different from those expre ssed or implied by such forward-looking
statements. For example, the modelling and assumptions upon which the work plans are based may not be maintained after further
testing or be representative of actual conditions within the Phoenix deposit. In addition, Denison may decide or otherwise be required
to discontinue its field test ac tivities or other testing, ev aluation and development work at W heeler River if it is unable to maintain or
otherwise secure the necessary resources (such as testing fac ilities, capital funding, regulatory approvals, etc.) or operation s are
otherwise affected by COVID-19 and its potent ially far-reaching impacts. Denison believe s that the expectations reflected in t his
forward-looking information are reasonable but no assurance can be given that these expectations will prove to be accurate and
results may differ materially from those anticipated in this fo rward-looking information. For a discussion in respect of risks and other
factors that could influence forward-looking events, please refer to the factors discussed in Denison’s Annual Information Form dated
March 26, 2021 or subsequent quarterly financial reports under the heading ‘Risk Factors’. These factors are not, and should not be
construed as being exhaustive.
Accordingly, readers should not place undue re liance on forward-looking statements. The forward-looking information contained i n
this news release is expressly qualified by this cautionary statement. Any forward-looking information and the assumptions made with
respect thereto speaks only as of the date of this news release. Denison does not undertake any obligation to publicly update or revise
any forward-looking information after the date of this news rel ease to conform such information to actual results or to changes in
Denison's expectations except as otherwise required by applicable legislation.
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Cautionary Note to United States Investors Concerning Estimates of Mineral Resources and Mineral Reserves: This press
release may use terms such as “measured”, “indicated” and/or “inferred” mineral resources and “proven” or “probable” mineral
reserves, which are terms defined with reference to the guidelines set out in the Canadian Institute of Mining, Metallurgy and Petroleum
(“CIM”) CIM Definition Standards on Mineral Resources and Mineral Reserves (“CIM Standards”). The Company’s descriptions of its
projects using CIM Standards may not be compar able to similar information made public by U.S. companies subject to the reportin g
and disclosure requirements under the United States federal securities laws and the rules and regulations thereunder. . United States
investors are cautioned not to assume that all or any part of m easured or indicated mineral res ources will ever be converted in to
mineral reserves. United States investors are also cautioned not to assume that all or any part of an inferred mineral resource exists,
or is economically or legally mineable.