Form 6-K
FORM 6-K
UNITED
STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
Report of Foreign Private Issuer
Pursuant to Rule 13a-16 or 15d-16
of the Securities Exchange Act of 1934
Date: July 6, 2007
Commission File Number: 001-33414
Denison Mines Corp.
(Translation of registrants name into English)
Atrium on Bay, 595 Bay Street, Suite 402, Toronto, Ontario M5G 2C2
(Address of principal executive offices)
Indicate by check mark whether the registrant files or will file annual reports under cover
Form 20-F or Form 40-F.
Form 20-F o Form 40-F þ
Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by
Regulation S-T Rule 101(b)(1): ___
Note: Regulation S-T Rule 101(b)(1) only permits the submission in paper of a Form 6-K
if submitted solely to provide an attached annual report to security holders.
Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by
Regulation S-T Rule 101(b)(7): ___
Note: Regulation S-T Rule 101(b)(7) only permits the submission in paper of a Form 6-K
if submitted to furnish a report or other document that the registrant foreign private
issuer must furnish and make public under the laws of the jurisdiction in which the
registrant is incorporated, domiciled or legally organized (the registrants home
country), or under the rules of the home country exchange on which the registrants
securities are traded, as long as the report or other document is not a press release, is
not required to be and has not been distributed to the registrants security holders, and,
if discussing a material event, has already been the subject of a Form 6-K submission or
other Commission filing on EDGAR.
Indicate by check mark whether by furnishing the information contained in this Form, the
registrant is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b)
under the Securities Exchange Act of 1934.
Yes o No þ
If Yes is marked, indicate below the file number assigned to the registrant in connection with
Rule 12g3-2(b): 82- ___
Signatures
Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused
this report to be signed on its behalf by the undersigned, thereunto duly authorized.
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Denison Mines Corp.
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/s/ Brenda Lazare
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Brenda Lazare |
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Canadian Counsel and Corporate Secretary |
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Date: July 6, 2007
2
EXHIBIT INDEX
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Exhibit Number |
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Description |
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1.
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Two consent letters from Scott Wilson RPA dated July 5, 2007; |
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2.
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NI43-101 Report entitled, Technical Report on the Elliot Lake Property, Elliot Lake
District, Ontario, Canada, prepared for Denison Mines Corp. dated June 29, 2007; and |
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3.
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Press Release dated July 5, 2007 |
3
Exhibit 1
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SCOTT WILSON RPA
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www.scottwilson.com
www.scottwilsonmining.com |
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Suite 501
55 University Ave.
Toronto, Ontario
M5J 2H7
Tel: (416) 947-0907
Fax: (416) 947-0395
Email: leo.hwozdyk@scottwilson.com |
FILED BY SEDAR
British Columbia Securities Commission
Alberta Securities Commission
Saskatchewan Financial Services Commission
The Manitoba Securities Commission
Ontario Securities Commission
Autorité des marché financiers
New Brunswick Securities Commission
Nova Scotia Securities Commission
Prince Edward Island Department of Provincial Affairs and Attorney General
Securities Division, Department of Justice Government of Newfoundland and Labrador
Dear Sirs/Mesdames:
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Re: |
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Denison Mines Corp. (the Company)
Filing of Technical Report dated June 29, 2007 |
I, Leo Hwozdyk, P.Eng., do hereby consent to the filing of the report titled Technical Report on
the Elliot Lake Property, Elliot Lake District, Ontario, Canada (the Report), prepared for Denison
Mines Corp. and dated June 29, 2007, on SEDAR. I also consent to the filing of the Report with the
securities regulatory authorities referred to above and any publication by them, including
electronic publication in the public company files on their websites accessible by the public.
Dated this 5th day of July, 2007
/s/ Leo R.
Hwozdyk
Leo R. Hwozdyk, P.Eng.
Associate Mining Engineer
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SCOTT WILSON RPA
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www.scottwilson.com
www.scottwilsonmining. com |
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Suite 501
55 University Avenue
P.O. Box 55
Toronto, Ontario M5 J2H7
Tel: (416) 947-0907
Fax:(416)947-0395
Email: lawrence. cochrane@scottwilson.com |
FILED BY SEDAR
British Columbia Securities Commission
Alberta Securities Commission
Saskatchewan Financial Services Commission
The Manitoba Securities Commission
Ontario Securities Commission
Autorité des marché financiers
New Brunswick Securities Commission
Nova Scotia Securities Commission
Prince Edward Island Department of Provincial Affairs and Attorney General
Securities Division, Department of Justice Government of Newfoundland and Labrador
Dear Sirs/Mesdames:
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Re: |
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Denison Mines Corp. (the Company)
Filing of Technical Report dated June 29, 2007 |
I, Lawrence Cochrane, P.Eng., do hereby consent to the filing of the report titled Technical
Report on the Elliot Lake Property, Elliot Lake District, Ontario, Canada (the Report), prepared
for Denison Mines Corp. and dated June 29, 2007, on SEDAR. I also consent to the filing of the
Report with the securities regulatory authorities referred to above and any publication by them,
including electronic publication in the public company files on their websites accessible by the
public.
Dated this 5th day of July, 2007
/s/ L.B.
Cochrane
Lawrence
B. Cochrane, Ph.D., P.Eng.
Principal Geologist
Exhibit 2
TECHNICAL REPORT ON THE
ELLIOT LAKE PROPERTY, ELLIOT
LAKE DISTRICT, ONTARIO, CANADA
PREPARED FOR
DENISON MINES CORP.
NI 43-101 Report
Authors:
Lawrence B. Cochrane, Ph.D., P. Eng.
Leo R. Hwozdyk, P. Eng.
June 29, 2007
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SCOTT WILSON RPA
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www.scottwilson.com
www.scottwilsonmining.com |
TABLE OF CONTENTS
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PAGE |
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1 SUMMARY |
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1-1 |
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Executive Summary |
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1-1 |
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Technical Summary |
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1-6 |
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2 INTRODUCTION AND TERMS OF REFERENCE |
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2-1 |
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3 RELIANCE ON OTHER EXPERTS |
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3-1 |
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4 PROPERTY DESCRIPTION AND LOCATION |
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4-1 |
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5 ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND
PHYSIOGRAPHY |
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5-1 |
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6 HISTORY |
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6-1 |
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Historic Mining Methods |
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6-2 |
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Mineral Processing |
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6-6 |
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Post Closure Activity |
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6-8 |
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Historic Mineral Resource and Mineral Reserve estimates |
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6-9 |
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7 GEOLOGICAL SETTING |
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7-1 |
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Regional Geology |
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7-1 |
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Property Geology |
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7-5 |
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8 DEPOSIT TYPES |
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8-1 |
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9 MINERALIZATION |
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9-1 |
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10 EXPLORATION |
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10-1 |
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11 DRILLING |
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11-1 |
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12 SAMPLING METHOD AND APPROACH |
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12-1 |
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13 SAMPLE PREPARATION, ANALYSES AND SECURITY |
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13-1 |
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14 DATA VERIFICATION |
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14-1 |
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15 ADJACENT PROPERTIES |
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15-1 |
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16 MINERAL PROCESSING AND METALLURGICAL TESTING |
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16-1 |
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17 MINERAL RESOURCE AND MINERAL RESERVE ESTIMATES |
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17-1 |
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18 OTHER RELEVANT DATA AND INFORMATION |
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18-1 |
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19 ADDITIONAL REQUIREMENTS |
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19-1 |
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20 INTERPRETATION AND CONCLUSIONS |
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20-1 |
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21 RECOMMENDATIONS |
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21-1 |
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22 REFERENCES |
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22-1 |
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SCOTT WILSON RPA
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www.scottwilson.com
www.scottwilsonmining.com |
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PAGE |
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23 SIGNATURE PAGE |
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23-1 |
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24 CERTIFICATE OF QUALIFICATIONS |
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24-1 |
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25 APPENDIX PROPERTY SITE VISIT PHOTOS |
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25-1 |
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LIST OF TABLES |
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Table 1-1
Historic Resource Developed and Undeveloped Denison Mine |
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1-3 |
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Table 1-2 Pre-Scoping Level Cost Estimate |
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1-6 |
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Table 4-1 List of Claims Covering the Mine Workings and Historic Resource and
Reserve Estimates |
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4-2 |
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Table 6-1 Relative REO Content of Uraninite Compared to Rare Earth Concentrate
Produced at Denison |
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6-8 |
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Table 6-2
Mineralization Developed and Undeveloped |
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6-15 |
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Table 6-3
Mineralization Developed |
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6-15 |
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Table 6-4
Mineralization Undeveloped |
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6-16 |
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Table 7-1 Huronian Supergroup, Elliot Lake Area |
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7-3 |
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Table 9-1 Uranium-Bearing and Associated Heavy Minerals |
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9-2 |
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Table 20-1
Historic Resource Developed and Undeveloped Denison Mine |
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20-3 |
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Table 21-1 Pre-Scoping Level Cost Estimate |
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21-2 |
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LIST OF FIGURES |
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PAGE |
Figure 4-1 Location Map |
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4-6 |
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Figure 4-2 Claim Map |
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4-7 |
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Figure 5-1 Property Access |
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5-4 |
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Figure 5-2 Site Infrastructure |
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5-7 |
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Figure 5-3 Location of Underground Mine Workings |
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5-8 |
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Figure 6-1 Mining Block Geometry |
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6-4 |
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Figure 7-1 District Geology |
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7-4 |
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Figure 7-2 North-South Cross Section through the Denison Mine Showing the Zones
and Reefs |
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7-6 |
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Figure 15-1 Adjacent Properties |
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15-2 |
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SCOTT WILSON RPA
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www.scottwilson.com
www.scottwilsonmining.com |
1 SUMMARY
EXECUTIVE SUMMARY
Scott Wilson Roscoe Postle Associates Inc. (Scott Wilson RPA) was retained by Denison
Mines Corp. (Denison) to prepare an independent Technical Report on the Denison Mine Property at
Elliot Lake. The Denison Mine Property contains the Denison and Stanrock Mines, which were closed
in 1992 following 35 years of continuous
production of
U3O8.
The purpose of this report is to review and comment on the historic
estimate of the mineral resources remaining on the Denison Mine
property. This Technical Report conforms to NI 43-101 Standards of
Disclosure for Mineral Projects.
A site visit was conducted on May 29, 2007, by Mr. Leo
Hwozdyk, representing Scott Wilson RPA, accompanied by Mr. Ian Ludgate, Manager of Denison
Environmental Services. The purpose of the visit was to tour the various mine installation sites
and report on their status.
Tables listing the final mineral resources and mineral reserves as estimated in April 1992
by the technical staff at the Mine, when the Denison Mine was closed, were provided to Scott Wilson
RPA by Denison. These tables list the mineral resources and mineral reserves by mining area,
classification, cut-off grades and by individual conglomerate reefs within the mining area. Scott
Wilson RPA contracted Mr. A. MacEachern, the former Mine Geologist at the Denison Mine and the
person who determined the final resource estimates in 1992, to provide a report describing the
methods used to estimate the mineral resource remaining at the time of the mine closure.
The uranium mineralization at the Denison Property is contained within quartz-pebble
conglomerate beds that vary in thickness from about five feet up to twelve feet. The conglomerate
beds, or reefs, are contained within two zones, the Main Zone and the Upper Zone, and each zone
contains multiple conglomerate beds separated by barren quartzite beds. The Main Zone and the Upper
Zone are separated by 120 ft. of quartzite.
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SCOTT WILSON RPA
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The historic resources were estimated using classical polygonal methods in 500 ft. by 500
ft. blocks. The grade and thickness of the individual conglomerate beds were estimated by averaging
the grade/thickness of the individual drill holes within the block. In the mined areas, packsack
diamond drill holes and chip sampling were used in conjunction with the mapping to outline the
mineralization. Adjustments were made to the grade and thickness based on underground observations
of grade/thickness changes and trends. For the undeveloped resources, and in particular for the
outlying resources, where the drill hole spacing was wider, the estimates of grade/thickness were
based on extrapolation of the information from the mined blocks.
A minimum bed thickness of six feet was used for resource estimation. Where the
bed was less than six feet, it was diluted at a grade of 0.20 lb/ton
U3O8 to reach the six-foot thickness. A constant tonnage factor of 11.6 ft.3/ton was used to estimate the
tonnage.
The areas that had been mined were digitized or planimetered to calculate the mined-out area
of each reef, and the mined area was not included in the resource estimate.
The mineral resource estimates were classified as Developed and Undeveloped. Developed
resources are those resources that have been developed for mining and remain after partial mining.
Undeveloped resources are located in blocks beyond existing development workings where no mining
has taken place.
The resources were further subdivided into primary mining and pillar mining representing
56% and 70%, respectively, of the total resource available after subtracting mining removal.
Resources identified as being contaminated (by intrusion beside the Keyes dyke), or contained
within a block that was part of a party wall, are not included in the compilation of the historic
resource estimate.
The historic resource estimates were determined at cut-off grades of 0.1 lb/ton, 0.8
lb/ton, 1.0 lb/ton, 1.25 lb/ton, 1.5 lb/ton, and 2.0 lbs/ton U3O8 .
Table 1-1 lists the historic
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SCOTT WILSON RPA
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www.scottwilson.com
www.scottwilsonmining.com |
estimate of the resource remaining, using the historic categories, at a cut-off grade of 0.80
lb/ton U3O8 (0.04% U3O8 ).
A mining recovery of 56% was used for the primary mining stage and 70% for primary plus
secondary (pillar) mining. The total resource remaining is also listed. The total resource
remaining represents 100% of the mineralization without applying any mining recovery factors. For
consistency with current reporting standards for mineral resources, Scott Wilson RPA recommends
that the historic resource estimates also be reported without applying mining recovery factors.
The historic resource estimates are based on the technical and economic parameters used by
Denison at the time of the mine closure in 1992 and do not reflect current technical and economic
parameters. Scott Wilson RPA recommends that the historic resource estimates be reported using a
0.80 lb/ton cut-off grade, which represents the undiluted cut-off grade for the underground
leaching over the last years of production and excludes the Interbedded Quartzite unit.
TABLE 1-1 HISTORIC RESOURCE DEVELOPED AND UNDEVELOPED
DENISON MINE
Denison Mines Corp. Elliot Lake
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% |
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Primary |
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Total Primary & |
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Total |
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Mined |
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Mining |
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Pillar Mining |
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Pillar Mining |
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Mineralization |
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Remaining |
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Remaining |
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Remaining |
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Remaining |
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Tons |
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Lb/t |
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Tons |
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Lb/t |
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Tons |
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Lb/t |
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Tons |
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Lb/t |
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M |
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U3O8 |
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M |
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U3O8 |
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M |
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U3O8 |
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M |
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U3O8 |
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Developed |
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24.0 |
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33.7 |
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1.20 |
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19.6 |
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1.55 |
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53.3 |
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1.32 |
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89.2 |
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1.29 |
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Undeveloped |
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0 |
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45.1 |
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1.13 |
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11.3 |
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1.13 |
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56.3 |
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1.13 |
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80.5 |
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1.13 |
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Total |
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14.0 |
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79.1 |
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1.17 |
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31.1 |
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1.39 |
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110.2 |
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1.23 |
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169.7 |
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1.21 |
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Notes:
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CIM definitions are not used. |
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2. |
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Historic resource estimates are reported at cut-off grades of 0.8 lb/t
U3O8 (0.04% U3O8 ). |
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3. |
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A minimum width of 6 feet was used. |
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4. |
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The total primary and pillar mining represents the estimated recoverable
resource based on the mining methods employed at the Denison Mine in 1992. |
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The total mineralization remaining represents the total amount of mineral remaining
in the ground without applying mining recovery factors. |
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The historic resource estimates cannot be verified and the estimates are not
necessarily indicative of the mineralization on the property. |
The mineral resource and mineral reserve estimates were conducted prior to the effective
date of National Instrument 43-101 on February 1, 2001, and do not conform to
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SCOTT WILSON RPA
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www.scottwilson.com
www.scottwilsonmining.com |
disclosure requirements under the Instrument. No records of the borehole location, borehole
logs, sample assays, underground mapping, or surveys of the mine openings are available to validate
the estimates. Scott Wilson RPA has been unable to verify the resource estimates, and notes that
the historic estimates are not necessarily indicative of the mineralization on the property that is
the subject of the technical report.
In the opinion of Scott Wilson RPA, although the historic resource estimate cannot be
validated, the estimate is considered to be reasonable based on the estimation methods used at the
time. The historic resource estimate is not considered to be relevant to current economic
assessment parameters.
Mr. Alan MacEachern, in his memo to Scott Wilson RPA, states that the most developed resources
are in blocks where there are workings with complete diamond drill hole samples. He indicates,
however, that, in his opinion, some of the blocks lack sufficient drilling data to be classified as
measured. Since the detailed data supporting the original resource estimates are not available,
it is not possible to verify the portions of the Developed resource that could be classified as
measured or the portions of the Developed resource that could be classified as indicated.
MacEachern also states that Undeveloped resources beyond the workings are the equivalent of
indicated and inferred resources. Again, however, it is not possible to determine the portion
of the Undeveloped resource that could be classified as indicated or the portions of the
Undeveloped resource that could be classified as inferred.
In addition to drill spacing, there are other factors that influence the classification. For
example poor ground conditions, resulting in the deterioration of the pillars, could result in
portions of the resource being unrecoverable and, therefore, not qualified to be categorized as a
mineral resource.
In the opinion of Scott Wilson RPA, without access to the drilling information, the historic
resource cannot be classified directly based on the CIM classification standards incorporated under
NI 43-101.
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SCOTT WILSON RPA
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www.scottwilson.com
www.scottwilsonmining.com |
RECOMMENDATIONS
Although the historic mineral resource estimate for the Denison Mine Property cannot be
validated, these estimates do provide sufficient information to carry out order-of-magnitude
economic assessments (pre-scoping level) to determine if additional exploration and evaluations are
warranted. As part of these studies, the following work is recommended:
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Conduct a detailed review of the 400 scale plans to determine the distribution of the
mineral resources by reef and classification and outline mining blocks for mining
evaluation and scheduling. |
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Determine the mine production potential and schedule assuming similar mining methods as
those used at the time of closure. |
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Estimate mining, processing, tailings management, and administration costs using
similar mining and processing methods that were used at the time the mine was closed as
a base case. |
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Estimate the capital costs for the mine, processing plant, and services and tailings
management facilities.
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Carry out an estimate on the amount of water in the mine; determine the amount
of U3O8 contained in the mine water and the recovery, to evaluate
the potential to extract U3O8 while the mine is being
dewatered. |
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Conduct order-of-magnitude economic assessments. |
COST ESTIMATE
A preliminary cost estimate for preparing a pre-scoping (conceptual) economic assessment
using the historic resource estimate and information available is provided in Table 1-2.
1-5
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SCOTT WILSON RPA
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www.scottwilson.com
www.scottwilsonmining.com |
TABLE 1-2 PRE-SCOPING LEVEL COST ESTIMATE
Denison Mines Corp. Dension Mine Property
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Item |
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Comments |
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Estimated Cost |
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Resource Distribution |
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Detailed assessment of 400-scale plans to |
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$15,000 |
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determine mining blocks |
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Mine plan and |
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Schedule blocks and determine mine |
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$15,000 |
schedule |
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production rate |
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Capex & Opex |
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Assume previous production methods |
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$15,000 |
Economic Evaluations |
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$10,000 |
Metallurgical tests |
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Extraction tests on mine water |
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$20,000 |
Report |
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$10,000 |
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Total |
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$85,000 |
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TECHNICAL SUMMARY
PROPERTY DESCRIPTION AND LOCATION
The Denison Mine Property is located in the Elliot Lake District approximately 15 km northeast
of the City of Elliot Lake, Ontario. Much of the property is located beneath Quirke Lake. Access
to the area is via Highway 108 north from Elliot Lake. The property is located in UTM Zone 17, at
approximately 5150000 N and 38000 E in Bouck and Buckles Townships.
LAND TENURE
The Denison Mine Property consists of 75 claims which include 34 Licenses of Occupation (MLO),
31 leases, one patent claim, and nine claims designated as FND status. The term FND (Federal
Nuclear Decommissioning) is a federal designation that is superior to any underlying provincial
designation, including patent claims. FND designated claims are subject to the federal governments
Nuclear Safety Act. In this case, FND refers to claims withdrawn from staking related to the
decommissioning of the tailings management areas in Elliot Lake. The terms of the FND claims may be
specific to each claim. Denison will need to confirm the status of these claims with regard to
exploration and development rights. The property covers 4,085 hectares not counting the patent
claim and the nine claims designated as FND status.
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SCOTT WILSON RPA
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www.scottwilson.com
www.scottwilsonmining.com |
SITE INFRASTRUCTURE
Currently the major facilities associated with the Denison Mine Property are:
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A tailings management facility including a water treatment plant |
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An all weather paved access road |
HISTORY
A total of 138,500 tonnes of uranium metal was produced from the Elliot Lake deposits from
1958 to the end of 1996. The average grade of the mine production from
12 mines was about 0.09% to 0.10%
U3O8.
The original 83 claims containing the Denison Mine deposit were acquired by Denison in
1954. The claims covered the down-plunge extension of the mineral zones identified near surface by
the Joubin syndicate which were subsequently developed through the Nordic Mine. Surface drilling
that same year resulted in the discovery of the Denison deposit. In 1957, the reserves were
estimated at 136.8 million tons averaging
2.78 lbs/ton U3O8 (0.139% U3O8) in
the conglomerate beds within the Main Zone. The No. 1 Shaft was sunk to a depth of 1,856 ft.
and the No. 2 Shaft was sunk to a depth of 2,766 ft. The mine was brought into production in 1957.
The Can-Met deposit, located southeast and adjacent to the Denison deposit, was discovered in
the same year and two shafts were sunk on the deposit in 1957. The initial reserves were estimated
at 6.6 million tons at an average grade of 1.83 lbs/ton U3O8 (0.092%
U3O8). In 1960, Can-Met Exploration Ltd. amalgamated
with Consolidated Denison Mines Ltd. to form Denison Mines Ltd.
The Stanrock property, located due south of the Denison Mine, was purchased by Stancan Uranium
Mines Limited (Stancan) in 1954 and Stancan explored the property in 1956 and 1957. Two shafts
were sunk on the property. Denison amalgamated with Stanrock Uranium Mines Ltd. in 1973. The
Denison and Stanrock Mines operated from 1957 through to March 11, 1992.
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The total production from the Denison Mine was 69.4 million tons grading 2.25
lbs/ton
U3O8 (0.123% U3O8). Total
shipments of U3O8 product were 147.3 million lbs
from mined ore, recovery of mine water, recovery from underground leaching, and recycle
materials from Cameco Corporation.
The mine was closed in 1992 due to the low price of U3O8
resulting from an oversupply on world markets and the opening of higher-grade mines in
Saskatchewan. All the buildings were dismantled, the mine openings were sealed, and the disturbed
lands were reclaimed and re-vegetated. Approximately 69 million tons of tailings were remaining and
these tailings were stored in two engineered basins designated as TMA1 and TMA2 (Tailings
Management Area2). A third tailings management area (TMA3) was built to contain approximately 6
million tons of tailings from the Stanrock Mine. The tailings are stored under a water cover of
approximately 0.9 m to control acid generation. The work on the tailings management areas was
completed in 1996 and the discharge from the tailings has been constantly monitored for about 11
years to ensure the discharge standards are met. The tailings areas are regulated through a
Uranium Mine Decommissioning Licence issued by the Canadian Nuclear Safety Commission. Since mine
closure in 1992, the facilities have remained in compliance.
GEOLOGY
The Elliot Lake area lies within the Southern Province of the Canadian Shield. The Southern
Province consists of a thick sequence of clastic sediments with minor sequences of marine limestone
and extrusive volcanic rocks. The clastic sequence is intruded by mafic and felsic intrusion. The
clastic sequence is referred to as the Huronian Supergroup and these sediments were deposited in
the early Proterozoic (2450 Ma to 2115 Ma) on Archean-aged metavolcanic and metasedimentary rocks
and granite intrusive rocks of the Superior Province. The majority of the uranium occurrences are
hosted in the lower portion of the Matinenda Formation which contain the basal sedimentary units of
the Huronian. The Huronian sediments were intruded by sills and dykes of the Nipissing diabase that
are dated at 2115 Ma.
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In the Elliot Lake area, the Huronian rocks are folded to form a shallow westward
plunging, gently folded syncline designated as the Quirke syncline. The limbs of the Quirke
syncline generally dip from 10o to 40o towards its axis.
Although the coarser grained quartzite beds in the lower Matinenda Formation commonly contain
low-grade uranium mineralization, the higher grade and more consistent zones of uranium
mineralization, are hosted within the beds of quartz-pebble conglomerate with disseminated pyrite
in the matrix. The uranium-bearing conglomerate beds are found within thicker sections of the
Matinenda Formation that overlie depressions in the underlying basement. These depressions are
termed channels and the Denison Mine property is located within the Quirke channel on the north
flank of the Quirke syncline.
At the Denison Mine, the uranium mineralization is contained within two zones, the Main Zone
and the Upper Zone, and each zone contains multiple beds of uraniferous, pyritic, quartz pebble
conglomerate, which are commonly called reefs. The Main Zone and the Upper Zone are separated by
120 ft. of quartzite. The reefs strike 105o to 120o and the dip ranges from
flat-lying to -60o south. Most of the reefs containing the remaining resources dip at
-10o to -20o south.
Each zone consists of interbanded conglomerate reefs and quartzite. Some reefs can be followed
for considerable distances, while others pinch and swell and are cut off by cross bedding over
relatively short distances. The better grade reefs have a minimal number of thinner quartzite
bands, well packed thicker conglomerate beds and coarse pyrite.
The Elliot Lake deposits are interpreted to be modified paleoplacer deposits and the source
rocks are believed to be pegmatitic granite located to the north. The uranium was released from the
granites as a result of weathering and transported as uraninite to the site of deposition in
channel systems in sedimentary basins formed in the Early Proterozoic. Subsequent diagenesis
resulted in the formation of the conglomerate beds intercalated
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within coarse sandstone with scattered pebbles and siltstone. Pyrite and other heavy minerals
were also with the quartz pebbles. In general, the uranium grade increases with increasing pyrite
content and pebble size. At the Denison Mine, the highest grade uranium mineralization occurred to
the lee of basement highs where the flow was more abruptly reduced.
Post-depositional modification of the uranium involved leaching of iron, uranium, thorium, and
silica from the detrital grains. The uranium and silica were deposited as coffinite; quartz and
detrital monazite were altered to urano-thorite; and uranium reacted
with
TiO2
to form brannerite. This post-depositional modification may have been caused by low Eh near-neutral
ground water. The uranium in the Denison Mine occurs primarily in the minerals brannerite and
uraninite.
ENVIRONMENTAL CONSIDERATIONS
The Denison Mine Property contains a tailings management area facility for the tailings
remaining from the former Stanrock Mine operation. The facility contains approximately 6 million
tons of tailings and is designated TMA-3. There are two other tailings management facilities (TMA-1
and TMA-2) that are located on the Denison property immediately west of the Denison Mine Property.
TMA-1 and TMA-2 contain approximately 69 million tons of tailings resulting from the previous
production at the Denison Mine. These tailings management areas are operated under the terms of
Uranium Mine Decommissioning permits issued by the Canadian Nuclear Safety Commission. The tailings
are contained within engineered structures and the tailings are under a water cover of
approximately 0.9 m. Programs to ensure the safe operation of these decommissioned properties
include: site security, radiation protection programs, health and safety programs, inspection
programs, tailings management operating programs, monitoring and reporting programs, and emergency
and contingency response programs as part of the licensing requirements. Denison has a financial
assurance plan with the province of Ontario and the Canadian Nuclear Safety Commission.
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2 INTRODUCTION AND TERMS OF
REFERENCE
Scott Wilson Roscoe Postle Associates Inc. (Scott Wilson RPA) was retained by Mr. W.
Kerr, Vice President of Exploration for Denison Mines Corp. (Denison), to prepare an independent
Technical Report on Denisons property at Elliot Lake covering the former Denison and Stanrock
Mines (Denison Mine Property), which were closed in 1992. The purpose of this report is to provide
Denison with the estimate of the historical mineral resources remaining in the former producing
Denison and Stanrock Mines in the Elliot Lake District and comment on the relevance of the historic
estimates. This Technical Report conforms to NI 43-101 Standards of Disclosure for Mineral
Projects.
Denison is a Canadian mining company based in Toronto and listed on the Toronto Stock Exchange
under the symbol DML, and on the American Stock Exchange under the symbol of DNN. Denisons major
activities are the mining, milling, extraction and sale of uranium, and the exploration and
development of mineral properties. The company holds mining assets in the Athabasca Basin region of
Saskatchewan and the southwest United States. Denisons share of production from the McClean Lake
Mill in
Saskatchewan in 2006 was 404,000 lbs of U3O8 and production at the
White Mesa Mill in Utah was approximately 280,000 lbs of U3O8.
Denison has exploration and development
properties in Canada, the United States, Argentina, Mongolia, and indirectly in Australia and
Zambia through its investments. Denison also has a mine decommissioning and environmental services
division with offices at Elliot Lake, Ontario, and is the manager
of Uranium Participation Corporation, a company that invests in, holds, and sells
U3O8 and UF6.
Currently, the major assets and facilities associated with the Denison Mine Property are:
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A historical mineral resource |
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A tailings management facility including a water treatment plant |
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An all weather paved access road |
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Sealed shafts and raises |
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A ramp from surface to the 800-foot level |
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Low voltage power supply 7,500/12,500 |
SOURCES OF INFORMATION
On March 12, 2007, Mr. Larry MacCormack, representing Scott Wilson RPA, visited the offices of
Denison in Toronto to receive two boxes of data relating to the Denison Mine Property. The
principal piece of information recovered from this data set is a letter report with accompanying
tables and plans that list the mineral resource and mineral reserve estimates remaining in the
Denison Mine at the time of closure.
Subsequently, on March 14 and 15, Mr. MacCormack visited the Denison Environmental Services
offices in Elliot Lake in the company of Mr. Alan MacEachern, former Mine Geologist at the Denison
Mine and Mr. Ian Ludgate, Manager of Denison Enviromental Services, to search for and examine data
relating to the Denison property that had been stored at that facility. An examination of map
drawers and a library search resulted in only a minimal amount of historical data being located.
On May 29, 2007, Mr. Leo Hwozdyk, P.Eng., a consulting mining engineer with Scott Wilson RPA,
carried out a site visit, accompanied by Mr. Ian Ludgate, Manager of Denison Environmental
Services. Mr. Hwozdyk was the former Mine Engineer at the Denison Mine. The purpose of the visit
was to tour the various mine installation sites and report on their status.
This Technical Report was prepared by Lawrence B. Cochrane, Ph.D., P.Eng., Scott Wilson RPA
Principal Geologist, and Leo Hwozdyk, P.Eng., Associate Mining Engineer with Scott Wilson RPA. The
principal documents used to determine the historic resources remaining at the Denison properties in
Elliot Lake and to provide comments on the estimation methods used are listed below.
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9 October 1991 Elliot Lake Mining Claims and Land Tenures, with 4 blueprint
Ministry of Northern Development and Mines Index to Land Disposition plans of townships
Bouck, Buckles, Gunterman and Joubin, dated Sept. 30, 1991, coloured to show Denison
properties. |
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Final Ore Reserves (Resources) 11 March 1992 with the following tables and plans
prepared by Mr. A. MacEachern: |
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Seven 1 = 400 plans numbered 31-2044 to 31-2050 showing the resource blocks. |
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Eighteen tables listing tonnage, grade/thickness, recovery factors, mining areas,
resource categories and cut-off grades. |
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A map showing Denison and Rio Algom Land Holdings (Oct. 2004). |
There are no drill logs, drill assays, drill sections, geologic plans, or any other data
supporting the historic resource estimate available. These data have all been lost.
Mr. A. MacEachern submitted a memo to Scott Wilson RPA clarifying and expanding on the
information in the above documents. The memo has been incorporated into this report.
Other sources of information are listed at the end of this report in Section 22 References.
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LIST OF ABBREVIATIONS
All the information is reported in the imperial system for consistency with the historic
reports. All currency in this report is Canadian dollars (C$) unless otherwise noted.
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m
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Micron
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kPa
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kilopascal |
°C
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|
degree Celsius
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|
kVA
|
|
kilovolt-amperes |
°F
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|
degree Fahrenheit
|
|
kW
|
|
kilowatt |
mg
|
|
microgram
|
|
kWh
|
|
kilowatt-hour |
A
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|
Ampere
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|
L
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|
litre |
a
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|
Annum
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|
L/s
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|
litres per second |
bbl
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Barrels
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m
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metre |
Btu
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|
British thermal units
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Ma
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Millions of years |
C$
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Canadian dollars
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m2
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square metre |
cal
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|
Calorie
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|
m3
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|
cubic metre |
cfm
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|
cubic feet per minute
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|
min
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|
Minute |
cm
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|
centimetre
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|
MASL
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|
metres above sea level |
cm2
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|
square centimetre
|
|
mm
|
|
Millimeter |
d
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|
Day
|
|
mph
|
|
miles per hour |
dia.
|
|
Diameter
|
|
MVA
|
|
megavolt-amperes |
dmt
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|
dry metric tonne
|
|
MW
|
|
Megawatt |
dwt
|
|
dead-weight ton
|
|
MWh
|
|
megawatt-hour |
ft
|
|
Foot
|
|
m3/h
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|
cubic metres per hour |
ft/s
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|
foot per second
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|
opt, oz/ton
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|
ounce per short ton |
ft2
|
|
square foot
|
|
oz
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|
Troy ounce (31.1035g) |
ft3
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|
cubic foot
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|
oz/dmt
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|
ounce per dry metric tonne |
g
|
|
gram
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|
ppm
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|
part per million |
G
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|
giga (billion)
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psia
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|
pound per square inch absolute |
Gal
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|
Imperial gallon
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psig
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pound per square inch gauge |
g/L
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gram per litre
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RL
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relative elevation |
g/t
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gram per tonne
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|
s
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Second |
Gpm
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|
Imperial gallons per minute
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st
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|
short ton |
gr/ft3
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|
grain per cubic foot
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stpa
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|
short ton per year |
gr/m3
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|
grain per cubic metre
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|
stpd
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short ton per day |
hr
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hour
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|
t
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metric tonne |
ha
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hectare
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tpa
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metric tonne per year |
hp
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|
horsepower
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tpd
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metric tonne per day |
in
|
|
inch
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|
US$
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|
United States dollar |
in2
|
|
square inch
|
|
USg
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|
United States gallon |
J
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Joule
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|
USgpm
|
|
US gallon per minute |
k
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|
kilo (thousand)
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|
V
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|
Volt |
kcal
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|
kilocalorie
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W
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Watt |
kg
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|
kilogram
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wmt
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|
wet metric tonne |
km
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kilometre
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yd3
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cubic yard |
km/h
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kilometre per hour
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yr
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Year |
km2
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square kilometre |
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3 RELIANCE ON OTHER EXPERTS
This report has been prepared by Scott Wilson Roscoe Postle Associates Inc. (Scott Wilson
RPA) for Denison Mines Corp. (Denison). The information, conclusions, opinions, and estimates
contained herein are based on:
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Information available to Scott Wilson RPA at the time of preparation of this report, |
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Assumptions, conditions, and qualifications as set forth in this report, and |
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Data, reports, and other information supplied by Denison and other third party sources. |
For the purpose of this report, Scott Wilson RPA has relied on ownership information provided
by Denison. Scott Wilson RPA has not carried out research on the legal aspects of the property
title or mineral rights for the Denison Mine Property and expresses no opinion as to the ownership
status of the property.
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4 PROPERTY DESCRIPTION AND LOCATION
The Denison Mine Property is located in the Elliot Lake District approximately 15 km
northeast of the City of Elliot Lake, Ontario. Access to the area is via Highway 108 north from the
City of Elliot Lake and the Stanrock Mine Road. The property is located in UTM Zone 17, at
approximately 5150000 N and 38000 E in Bouck and Buckles Townships. A location map is shown in
Figure 4-1.
LAND TENURE
The Elliot Lake property of Denison initially comprised two mining leases, the Denison Mine
property lease situated in Bouck Township and Buckles Township and the Stanrock property lease
lying wholly within Buckles Township. The property is referred to as the Denison Mine Property. The
property map is shown in Figure 4-2.
Scott Wilson RPA reviewed the claim status on the web site of the Ontario Ministry of Mines
and Northern Development (MNDM) to determine the status of the claims covering the area hosting the
historic resource and reserve estimates compiled in the computer-generated tables made available by
Denison. The list of claims is shown in Table 4-1. The Denison Mine Property consists of 75
claims, which include 34 Licences of Occupation (MLO), 31 leases, one patent claim, and nine claims
designated as FND status.
The term FND (Federal Nuclear Decommissioning) is a federal designation that is superior to
any underlying provincial designation including patent claims. FND designated claims are subject to
the federal governments Nuclear Safety Act. In this case, FND refers to claims withdrawn from
staking related to the decommissioning of the tailings management areas in Elliot Lake. The terms
of the FND claims may be specific to each claim. Denison will need to confirm the status of these
claims with regard to exploration and development rights.
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The total area covered by the MLO and lease-held claims is 4,085.41 hectares. The claim
boundaries are not surveyed.
TABLE 4-1 LIST OF CLAIMS COVERING THE MINE WORKINGS AND
HISTORIC RESOURCE AND RESERVE ESTIMATES
Denison Mines Corp. Elliot Lake
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Claim No. |
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Type |
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Area |
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Tenure |
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Twp |
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S67433
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Licence of Occupation (MLO)
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178.54 |
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M Only
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Bouck |
S67434
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(MLO)
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178.54 |
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M Only
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Bouck |
S100431
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10 Year lease(Jan,2010)
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3.07 |
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M Only
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Buckles |
S67832
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(MLO)
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25.04 |
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M Only
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Buckles |
S68375
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(MLO)
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43.94 |
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M Only
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Bouck |
S68376
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(MLO)
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43.94* |
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M Only
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Bouck |
S96595
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10 Year lease(Apr,2008)
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12.56 |
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M & S
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Bouck |
S96593
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10 Year lease(Apr,2008)
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19.95 |
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M & S
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Bouck |
S99109
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10 Year lease(Jan,2010)
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9.05 |
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M Only
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Buckles |
S120653
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21 Year lease(Sep.2007)
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5.21 |
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M Only
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Buckles & Bouck |
S120652
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21 Year lease(Sep,2007)
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6.96 |
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M Only
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Buckles |
S75785
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10 Year lease(Aug,2016)
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14.77 |
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M & S
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Buckles |
S96592
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10 Year lease(Oct,2016)
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15.71 |
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M & S
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Buckles |
S96591
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10 Year lease(Oct,2016)
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16.96 |
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M & S
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Bouck |
S96590
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10 Year lease(Oct,2016)
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10.95 |
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M & S
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Buckles |
S96589
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10 Year lease(Oct,2016)
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17.54 |
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M & S
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Buckles |
S75782
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10 Year lease(Aug,2016)
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10.72 |
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M & S
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Buckles |
S75784
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10 Year lease(Oct,2016)
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13.39 |
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M & S
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Buckles |
S67833
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FND
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Buckles |
S67834
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FND
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Buckles |
S67835
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FND
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Buckles |
S67836
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FND
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Buckles |
S67837
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FND
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Buckles |
S67840
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FND
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Buckles |
S67841
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FND
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|
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|
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Buckles |
S67842
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FND
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|
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|
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Buckles |
S67843
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FND
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|
|
|
|
|
|
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Buckles |
S67838
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(MLO)
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|
25.04 |
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M Only
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Buckles |
4-2
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SCOTT WILSON RPA
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Claim No. |
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Type |
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Area |
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Tenure |
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Twp |
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S67839
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(MLO)
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25.04 |
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M Only
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Buckles |
S69615
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10 Year Lease(Sep,2016)
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|
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10.60 |
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M & S
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Buckles |
S69620
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10 Year Lease(Sep,2016)
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11.82 |
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M & S
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Buckles |
S69621
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10 Year Lease(Sep,2016)
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|
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9.91 |
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M & S
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Buckles |
S69626
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10 Year Lease(Sep,2016)
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12.47 |
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M & S
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Buckles |
S69627
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10 Year Lease(Sep,2016)
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9.71 |
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M & S
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Buckles |
S69631
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10 Year Lease(Sep,2016)
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10.13 |
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M & S
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Buckles |
S69630
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10 Year Lease(Sep,2016)
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9.75 |
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M & S
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Buckles |
S69629
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10 Year Lease(Sep,2016)
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9.30 |
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M & S
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|
Buckles |
S69628
|
|
10 Year Lease(Sep,2016)
|
|
|
11.57 |
|
|
M & S
|
|
Buckles |
S69623
|
|
10 Year Lease(Sep,2016)
|
|
|
16.55 |
|
|
M & S
|
|
Buckles |
S69624
|
|
10 Year Lease(Sep,2016)
|
|
|
3.33 |
|
|
M & S
|
|
Buckles |
S69625
|
|
10 Year Lease(Sep,2016)
|
|
|
12.85 |
|
|
M & S
|
|
Buckles |
S69622
|
|
10 Year Lease(Sep,2016)
|
|
|
2.38 |
|
|
M & S
|
|
Buckles |
S69616
|
|
10 Year Lease(Sep,2016)
|
|
|
5.26 |
|
|
M & S
|
|
Buckles |
S69617
|
|
10 Year Lease(Sep,2016)
|
|
|
2.50 |
|
|
M & S
|
|
Buckles |
S69618
|
|
10 Year Lease(Sep,2016)
|
|
|
20.21 |
|
|
M & S
|
|
Buckles |
S69619
|
|
10 Year Lease(Sep,2016)
|
|
|
17.13 |
|
|
M & S
|
|
Buckles |
S68374
|
|
(MLO)
|
|
|
43.94 |
|
|
M Only
|
|
Bouck |
S68372
|
|
(MLO)
|
|
|
43.94 |
|
|
M Only
|
|
Bouck |
S68373
|
|
(MLO)
|
|
|
43.94 |
|
|
M Only
|
|
Bouck |
S86076
|
|
(MLO)
|
|
|
134.84 |
|
|
M Only
|
|
Bouck |
S86077
|
|
(MLO)
|
|
|
134.84 |
|
|
M Only
|
|
Bouck |
S86078
|
|
(MLO)
|
|
|
134.84 |
|
|
M Only
|
|
Bouck |
S86125
|
|
(MLO)
|
|
|
134.84 |
|
|
M Only
|
|
Bouck |
S86123
|
|
(MLO)
|
|
|
134.84 |
|
|
M Only
|
|
Bouck |
S86126
|
|
21 Year Lease(Apr,2018)
|
|
|
21.79 |
|
|
M & S
|
|
Buckles |
S86079
|
|
(MLO)
|
|
|
178.54 |
|
|
M Only
|
|
Bouck |
S86080
|
|
(MLO)
|
|
|
178.5 |
|
|
M Only
|
|
Bouck |
S86081
|
|
(MLO)
|
|
|
134.8 |
|
|
M Only
|
|
Bouck |
S86072
|
|
(MLO)
|
|
|
81.69 |
|
|
M Only
|
|
Bouck |
S86075
|
|
(MLO)
|
|
|
134.84 |
|
|
M Only
|
|
Bouck |
S86124
|
|
(MLO)
|
|
|
134.84 |
|
|
M Only
|
|
Bouck |
S67432
|
|
(MLO)
|
|
|
178.54 |
|
|
M Only
|
|
Bouck |
S67431
|
|
(MLO)
|
|
|
178.54 |
|
|
M Only
|
|
Bouck |
4-3
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|
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Claim No. |
|
Type |
|
Area |
|
Tenure |
|
Twp |
|
S67430
|
|
(MLO)
|
|
|
178.54 |
|
|
M Only
|
|
Bouck |
S67429
|
|
(MLO)
|
|
|
178.54 |
|
|
M Only
|
|
Bouck |
S86070
|
|
(MLO)
|
|
|
95.72 |
|
|
M Only
|
|
Bouck |
S86069
|
|
(MLO)
|
|
|
95.72 |
|
|
M Only
|
|
Bouck |
S67428
|
|
(MLO)
|
|
|
95.72 |
|
|
M Only
|
|
Bouck |
S86071
|
|
(MLO)
|
|
|
95.72 |
|
|
M Only
|
|
Bouck |
S86073
|
|
(MLO)
|
|
|
95.72 |
|
|
M Only
|
|
Bouck |
S86074
|
|
(MLO)
|
|
|
95.72 |
|
|
M Only
|
|
Bouck |
S86118
|
|
(MLO)
|
|
|
95.72 |
|
|
M Only
|
|
Bouck |
S67436
|
|
(MLO)
|
|
|
95.72 |
|
|
M Only
|
|
Bouck |
S86119
|
|
Patent
|
|
|
|
|
|
|
|
Bouck |
S86064
|
|
(MLO)
|
|
|
102.03 |
|
|
M Only
|
|
Bouck |
75
|
|
|
|
|
4085.41 |
|
|
|
|
|
In addition to these claims, there are also claims held under lease, Licences of
Occupation, and patent by Denison, and additional claims shown as FND status west of the block
containing the historic resource and reserve estimates at the Denison Mine Property.
There are no royalties, back-in-rights, payments, or other encumbrances attached to the
property.
ENVIRONMENTAL LIABILITIES
The Denison Mine Property contains a tailings management area facility, with the tailings
remaining from the former Stanrock Mine operation. The facility contains approximately 6 million
tons of tailings and is designated TMA-3. There are two other tailings management facilities (TMA-1
and TMA-2) that are located on the Denison property immediately west of the Denison Mine Property.
TMA-1 and TMA-2 contain approximately 69 million tons of tailings from the Denison Mine. These
tailings management areas are operated under the terms of Uranium Mine Decommissioning Licences
issued by the Canadian Nuclear Safety Commission. The tailings are contained within engineered
structures and the tailings are under a water cover of approximately 0.9
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m (Laliberte et al., 2003). Construction of the tailings management areas was completed in 1996.
General programs to ensure the safe operation of these decommissioned properties include: site
security, radiation protection programs, health and safety programs, inspection programs, tailings
management operating programs, monitoring and reporting programs, and emergency and contingency
response programs as part of the licensing requirements. Denison has a financial assurance plan
with the province of Ontario and the Canadian Nuclear Safety Commission.
PERMITTING REQUIREMENTS
The permitting required for the development of a mine in Ontario falls under the jurisdiction
of both the Ontario Provincial Government and the Federal Government. Although the provinces have
jurisdiction over exploration and mine development, the federal government retains jurisdiction
over inland fisheries and navigable waters. For uranium mines, the federal government also has
jurisdiction, which it regulates through the Canadian Nuclear Safety Commission (CNSC).
During the exploration and preliminary evaluation stages, no special permits are required.
However, the Ontario Ministry of Labour should be notified if exploration or drilling crews are
working on the property. Permits are required when the evaluation moves to the advanced exploration
stage. For a uranium property, an environmental assessment is required before the permit can be
issued and the environmental assessment requires public hearings.
Advanced exploration means the excavation of an exploratory shaft, adit, or decline, the
extraction of material in excess of the prescribed quantity (1,000 tonnes), where the extraction
involves the disturbance or movement of prescribed material located above or below the surface of
the ground, or the installation of a mill for test purposes or any other prescribed work (includes
the excavation of backfilled raises, shafts, or adits).
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5 ACCESSIBILITY, CLIMATE, LOCAL
RESOURCES, INFRASTRUCTURE AND
PHYSIOGRAPHY
ACCESSIBILITY
The property is located approximately 15 km northeast of the City of Elliot Lake. It is
accessed from Highway 108 by travelling east on the Stanrock Road which is an all weather paved
road. The location of the property and access roads relative to the City of Elliot Lake are shown
in Figure 5-1.
PROXIMITY TO POPULATION CENTRES AND TRANSPORT
Based on the 2006 census, the City of Elliot Lake has a population of 11,549 people. However,
in the period from 1956 to 1992 when the uranium mines were operating in the district, the
population reached about 25,000 people. Much of the infrastructure supporting the mining industry
is still in place.
The City of Elliot Lake is located 160 km west of Sudbury and 180 km east of Sault Ste. Marie.
These communities are connected by highway with Elliot Lake. The Sault Ste. Marie, Ontario Sault
Ste. Marie, Michigan border crossing is located 200 mile west of Elliot Lake. The city is located
540 km north of Toronto. There is a railway line 26 km south at the intersection of Highways 108
and 17 (Trans Canada Highway). There are two deep water ports near the same highway intersection on
the North Channel of Lake Huron. One port is currently used by Lafarge at the town of Sprague,
located 34 km from Elliot Lake, and the other is the old Rio Algom port at Thessalon, now used by a
yacht club. Thessalon is located 112 km from Elliot Lake. Elliot Lake airport has a runway that is
30 m wide and 1,372 m long. The airport is maintained year round and is certified by Transport
Canada for airline service. Air Bravo Corporation operates an air ambulance service and provides
charter service.
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Cameco Corporation operates a uranium refinery at Blind River, located 50 km from the property
on Highway 17. Lafarge operates a cement plant at Sprague, which is also located on Highway 17 on
the North Shore of Lake Huron.
CLIMATE
The climate in the Elliot Lake region is suitable for year round mining and processing
operations. The average winter temperature (December to February) is -9ºC and the average summer
temperature (June to August) is +16ºC. The average annual winter snowfall is 285 cm and the
average annual rainfall is 80.5 mm for a total precipitation of 109 mm. (A factor of 0.1 is used to
convert snowfall to precipitation.) The wind direction is predominantly from the north from
December through to April and the southwest and south the rest of the year.
LOCAL RESOURCES AND SERVICES
The Elliot Lake hydro system has the capacity to supply electricity to 25,000 people plus six
operating mines. The entire hydro infrastructure is still in place, although it is not all in
current use. Hook up and commissioning would be required. Natural gas is also available. Elliot
Lake has a number of fibre optic service access points within the community, enabling high-speed
broadband access.
The median age of the population is 49.4 years, with about 85% of the population over 15 years
of age. Based on October to December 2005 statistics, the labour force in Elliot Lake is 3,855, or
about 38% of the total population over 15 years of age. This low participation rate reflects the
large number of retirees in the City. The unemployment rate at the same period was 13%.
Approximately 5% of the population is currently employed in the mining industry. The Denison Mine
Property is also within commuting distance to the communities on the north shore of Lake Huron.
There are two fully serviced industrial park areas within the community and existing buildings
are available for lease or purchase. Elliot Lake has a full compliment of educational, medical, and
social services.
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The City of Elliot Lake was originally developed for the sole purpose of uranium mining and
processing and remained a single-resource community until the early 1990s when the mines closed.
With the mine closures, Elliot Lake, in conjunction with the mining companies, developed
alternative economic plans. The vacant homes were marketed and sold or rented to retirees who have
been moving to Elliot Lake since the mine closures. This initiative has helped to stabilize the
population and allowed the city to develop a tourism and recreational infrastructure. These two
initiatives, retirement living and outdoor tourism, coupled with the development of business
opportunities, are described as the three pillars of the local economy by the local Economic
Development Office.
The development of a uranium mining and processing facility at Elliot Lake is consistent with
the economic objectives and strategy of the City of Elliot Lake, however, the industry will need to
ensure that the development and operations are compatible with the retirement and tourism
initiatives.
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SITE INFRASTRUCTURE AND SURFACE RIGHTS
The property is an abandoned mine site. All of the buildings and services have been removed
and all of the shafts have been capped. There is one tailings management area located on the
Denison Mine Property and two tailings management areas located on the adjacent Denison property.
Low voltage power 7,500/12,500 is available. The high voltage line was decommissioned north of
Elliot Lake.
The location of the former shafts and the tailings management areas are shown in Figure 5-2.
Denison No. 1 Shaft collar is in good shape and is capped with removable concrete beams, but the
shaft is plugged with debris and not accessible. A surface adit located between No. 1 Shaft and 15
Panel Raise was covered with rock fill. Denison No. 2 Shaft is open to the water level, and the
collar is in good shape and is capped with removable concrete beams. Stanrock No. 2 Shaft is
plugged with debris and the collar is questionable. Stanrock No. 1 Shaft is opened and in good
shape. Both Stanrock shafts are capped with removable concrete beams. CanMet No. 1 Shaft was
widened for ventilation purposes and is no longer available as a shaft. There is also debris in
the shaft. CanMet No. 2 Shaft may also have some debris in the shaft. Both CanMet shafts were
capped with removable concrete beams. Three ventilation raises are located on Puhky Island,
Knowles Island and Roman Island in Quirke Lake. Demolition debris from the decommissioning of these
ventilation fan installations has been dumped down the Pukhy Island Raise. Other vertical openings
used for disposal of demolition debris include North West, South West, and 15 Panel Raises. The
North West and 15 Panel Raises were filled with debris to within approximately 30 m of the collar,
then rock fill was added, and the raises were capped with a final layer of glacial till. The South
West Raise was half filled with approximately 900,000 yd.3 of slurry tailings from the
Smith Lake tailing containment area as well as demolition debris from the Denison mill. The raise
was then capped with removable concrete beams
Figure 5-3 shows the extent of the mine workings at Denison at the time of closure, and this
area contains the historic resource and reserve estimates. The mine workings shown in Figure 5-3 do
not include the older Stanrock and Canmet mine workings.
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A water treatment plant and a pump station are located on the property to treat the discharge
water from the tailings management area. Stanrock has one treatment plant and one pump station. The
tailings area is serviced by a public road to the gate and private internal roads. Stanrock
tailings are contained by Dams A, B, C, and D. Other dams include Dams G, J, K, F and the Orient
Lake outlet berm.
TOPOGRAPHY, ELEVATION AND VEGETATION
The Elliot Lake area is underlain by moderately rugged topography, with elevations ranging
from 320 m to 430 m. Steep cliffs form south-facing slopes while the north slopes are gentler and
tend to follow the dip of the stratigraphy. The ridges trend east-northeast along the strike of the
rocks.
Lakes and streams tend to develop along the strike of less resistant strata and generally
trend east to west. Some streams and lakes trend northwest following fault structures. The Denison
Mine Property is located within the Serpent River drainage system. A large portion of the Denison
Mine Property is located underneath Quirke Lake, which drains southeast through the Serpent River
into Whiskey Lake and then south to Lake Huron.
The valleys are covered with hemlock and cedar trees and the ridges are wooded with maple,
oak, birch and poplar trees.
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6 HISTORY
Uranium mineralization was discovered in Long Township at the Pronto Mine Site near Blind
River in 1949. Due to low grades indicated by the initial drilling, the claims were allowed to
lapse. The claims were restaked by F. Joubin who suspected that the lower grades may be due to the
leaching of the uranium near surface. Drilling was conducted on the claims in April 1953. Although
the initial holes showed lower grades, the later holes intersected higher grade uranium with grades
averaging 0.13% U3O8. Before releasing the results of the
drilling, Joubin and his associates carried out extensive prospecting in the district. The search
was focused on the occurrence of pyrite-bearing quartz pebble conglomerates located at or near the
contact between the Mississagi sediments and the underlying Archean rocks, based on the geology of
the original discovery site.
The publication of the results of the 1953 drilling at the Pronto Mine site and the disclosure
of the staking program led to a massive staking rush in the area. The prospecting quickly resulted
in the discovery of several zones of radioactive conglomerate in the Elliot Lake area, and more
than 1,400 claims were staked. Although several radioactive occurrences were found between Sudbury
and Sault Ste. Marie, however, only the properties in the Elliot Lake area became productive.
The original 83 claims containing the Denison Mine deposit were originally acquired by Denison
in 1954. The claims covered the down-plunge extension of the mineral zones identified near surface
by the Joubin syndicate which were subsequently developed through the Nordic Mine. Surface drilling
that same year resulted in the discovery of the Denison deposit. In 1957, the company estimated
reserves at 136.8 million tons averaging 2.78 lbs/ton U3O8 in the conglomerate reefs within the Main Zone. The No. 1 Shaft was sunk to a depth of 1,856
ft. and the No. 2 Shaft was sunk to a depth of 2,766 ft. The mine was brought into production in
1958.
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The Can-Met deposit, located southeast and adjacent to the Denison deposit, was discovered in
the same year and two shafts were sunk on the deposit in 1957. Production from the Denison Mine
began in late 1957. The initial reserves were estimated at 6.6 million tons at an average grade of 1.83 lbs per ton U3O8. In 1960,
Can-Met Exploration Ltd. amalgamated with Consolidated Denison Mines Ltd. to form
Denison Mines Ltd.
The Stanrock property, located due south of the Denison Mine, was purchased by Stancan Uranium
Mines Limited (Stancan) in 1954 and Stancan explored the property in 1956 and 1957. Two shafts were
sunk on the property. Denison amalgamated with Stanrock Uranium Mines Ltd. in 1973. The Denison and
Stanrock Mines operated from 1957 through to March 11, 1992.
A total of 138,500 tonnes of uranium metal was produced from the Elliot Lake deposits from
1958 to the end of 1996. The average grade of the mine production from 12 mines was about 0.09% U3O8 to 0.10% U3O8.
The total production from the Denison Mine was 69.4 million tons grading 2.25 lbs/t U3O8. Total shipments of U3O8 product were
147.3 million lbs from mined ore, recovery from mine water, recovery from underground
leaching, and recycle materials from Cameco Corporation.
HISTORIC MINING METHODS
CONVENTIONAL MINING
Mining method employed at the Denison Mine was primarily room-and-pillar mining. Denison
carried out development work in ore and used mobile diesel equipment to load ore to conveyorways
that transported the ore to the mine shafts.
The mine was separated into mining blocks consisting of 50-foot wide rooms and 29-foot wide
rib pillars. The blocks were enclosed by 29-foot wide barrier pillars. The pillars were accessed
by a 20-foot wide drift. Figure 6-1 illustrates the geometry of the mining blocks. The primary
extraction of the rooms resulted in a mining recovery of
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56% of the mining block. The area of the mining block is shown in Figure 6-1. Following the primary
mining, slots were driven to recover a portion of the pillars. The calculated recovery of the total
block following the secondary mining of the pillars, based on the design layout, is 72%.
For the historic mineral resource estimates, a mining recovery of 56% was used for the primary
mining and 70% when both primary and secondary mining were completed.
Some of the major considerations in the mine design were governed by ground control
requirements, reef thickness and environmental considerations. Ground conditions in the Elliot Lake
area may be generally described as good to excellent, and support may be controlled by
application of sound rock mechanics principles that control the relationship of span, pillar width,
ore thickness, with extraction decreasing with increased depth. Extensive incidents of rock
bursting have occurred, primarily due to the violent failure of the pillars caused by the increase
in the perpendicular stress as a result of the mining (Hedley, 1983).
Reef thickness was a controlling factor in method selection, together with variations in dip.
In areas with narrow thickness and steeper dip, conventional mining with jacklegs and slushers was
used, whereas in both flatter and thicker areas, mining was carried out using mobile diesel
equipment. Expansion of the production near the end of the mine life was centred on the development
of low profile equipment in the thinner reefs remaining.
Environmental considerations were also important to ensure sufficient ventilation was provided
to control silica dust, diesel emissions, and radiation. The stringent standards require high
volumes of ventilation. Design for ventilation requirements was based on 175 cfm per ton mined.
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UNDERGROUND LEACHING
Shortly after production began at Elliot Lake, it was recognized that the acidity of the
mine water was increasing which was resulting in corrosion problems in pipes and pumps. It was also
noted that the uranium content of the acid water was elevated. Starting in 1960, small amounts of
uranium were extracted from the mine water being pumped to surface. Programs were begun to wash
down old stopes and recover additional uranium from the water.
Sulphuric acid was generated due to bacterial leaching of the pyrite in the ore. The bacterial
leaching produced ferric iron and sulphate and the process was self-sustaining. At the Stanrock
Mine, the bacterial leaching program was expanded to include caved-in areas, waste piles, and
low-grade ore stockpiles underground. This washing operation was continued from December 1962 until
the mine closed in 1970. The conventional mining operation was discontinued entirely in 1964 and
all production came from bacterial leaching.
Denison had maintained a limited underground bacterial leaching program since the mid-1960s.
In 1980, in a project to increase production from leaching activities and to lower the mining
costs, Denison initiated a research and development program on the bacterial leaching process to
determine the optimal physical, biological and chemical conditions required to increase the
leaching rate. The underground testing was carried out on the broken ore blasted into the open
stopes after the primary ore extraction was completed. Air lines were installed on the floor of the
stopes and dams were built at the stope entrance. The stopes were sealed and then flooded to
prepare the broken ore for leaching. The stopes were then drained and air was introduced to
accelerate the bacterial leaching process. The stopes were flooded about once a month to refresh
the leaching activity.
In one test, underground spray leaching was carried out. A travelway was prepared on one side
of the broken ore for the installation of the hoses over the broken ore pile. The leaching was
carried out by spraying the piles of broken muck.
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Based on the use of improved bacteria and better preparation of the broken ore and the
introduction of oxygen into the stopes, the leaching portion of Denisons production increased to
about 20% of its total production in 1990. In 1989, the planned production break assigned to heap
leaching was about 1.4 million tons (Denison 1988 Annual Report). The Denison report stated that
the uppers drilling (mineralization in the hanging wall of the stopes) accounted for about 83% of
the total production and jack leg drilling (pillar recovery) for the remainder. It was expected
that 56% of the leaching production would originate from flood leaching and the other 44% from
spray leaching and mine water.
Metal recoveries up to 70% on run-of-mine ore were reported by Marchbank (1986), but with
leaching times of 12 to 18 months. Further production trials were carried out to improve the
recoveries, but no reports are available on these tests.
The bacterial leaching program was curtailed when the mine was closed. Prior to closing,
Denison had planned on increasing the portion of production from the underground leaching.
MINERAL PROCESSING
URANIUM EXTRACTION
The Denison plant consisted of a conventional crushing and grinding circuit. The ore was
ground to 60% passing 200 mesh. The slurry was dewatered using neutral thickeners and filters in
preparation for leaching. The dewatered pulp, about 75% solids, was pumped into a series of Pachuca
tanks connected by launders. The pulp was agitated with air and heated to 75°C with
steam. Sulphuric acid at 93% concentration was added to the pulp in the first Pachucas and the
acidified pulp was cascaded from one tank to the next. An oxidant was added to accelerate the
chemical leaching process. After approximately 40 hours in the Pachuca tanks, about 96% of the
uranium had been leached from the ore
and was dissolved in the acid solution. (In the 1988 annual report, Denison reported
U3O8 recoveries of about 93%.)
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Lime slurry was added to the pulp to adjust acidity. It was thickened either by washing
thickeners followed by two-stage washing drum filters or five-stage counter current decantation.
The uranium-bearing solution (pregnant solution) was separated from the solids and sent to the ion
exchange circuit for uranium recovery. The solids were washed twice to remove valuable entrained
solution, treated with lime, and sent as waste to a controlled tailings disposal area.
The pregnant solution was clarified and pumped to the adsorption side of the ion exchange
plant. The solution from the underground leaching program was also sent to the clarifiers and
combined with the plant production for uranium extraction. The uranium was stripped from the resin
using a nitric acid solution and pumped to the precipitation stage. The barren solution was
neutralized with lime and pumped to the tailings facility. The solution containing the uranium was
partially neutralized with lime and ammonia and impurities were removed by filtration. The
remaining solution was then neutralized with ammonia to separate the uranium as ammonium diuranate
(yellowcake). The yellowcake was filtered, washed and dried, and packed in steel drums for
shipment.
RECOVERY OF RARE EARTH OXIDES (REO)
In 1986, Denison built a plant to extract yttrium oxide (Y2O3),
a rare earth, as a by-product from the uranium production. The ion exchange barren solution generated in the uranium
processing plant was utilized as the feedstock for the yttrium recovery plant. Denison operated the
plant until 1990.
The REO are contained with the mineral monazite and uraninite. Theis (1979) compared the rare
earth oxide content of uraninite, based on a sample from Roscoe (1969) to the rare earth oxide
content of the rare-earth concentrate produced at the Denison Mine as shown in Table 6-1. The
composition of the concentrate suggests that the REO were recovered primarily from uraninite rather
than monazite.
6-7
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SCOTT WILSON RPA
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TABLE 6-1 RELATIVE REO CONTENT OF URANINITE COMPARED TO
RARE EARTH CONCENTRATE PRODUCED AT DENISON
Denison Mines Corp. Elliot Lake
|
|
|
|
|
Rare Earth Oxide |
|
% of Total REO in Uraninite |
|
% of Total REO in Concentrate |
|
Y2O3 |
|
40.7 |
|
40.6 |
Nd2O3 |
|
12.1 |
|
8.7 |
CeO2 |
|
10.6 |
|
3.7 |
Dy2O3 |
|
12.4 |
|
10.6 |
Sm2O3 |
|
6.4 |
|
8.1 |
Er2O3 |
|
6.1 |
|
5.1 |
Pr2O3 |
|
3.1 |
|
1.8 |
La2O3 |
|
1.2 |
|
1.3 |
Gd2O3 |
|
7.8 |
|
8.7 |
POST CLOSURE ACTIVITY
The mine was closed in 1992 due to the low price of U3O8
resulting from an oversupply on world markets and the opening of higher-grade mines
in Saskatchewan. All the buildings were dismantled, the mine openings were sealed and the disturbed
lands were reclaimed and re-vegetated. Approximately 69 million tons of tailings were remaining at
the time the mine was closed and these tailings were stored in two engineered basins designated as
TMA1 and TMA2 (Tailings Management Areas). At TMA1, a portion of the tailings were moved to TMA2
and a portion was stored underground through the Southwest Raise. The tailings and sludge flowed to
deeper parts of the operation mainly towards the south west portion of the mine. Tailings and
sludge may need to be relocated within the mine in order to gain access to new areas in any future
development.
A third tailings management area (TMA3) was built to contain approximately 6 million tons of
tailings from the Stanrock Mine. The tailings are stored under a water cover of approximately 0.9 m
to control acid generation (Laliberte et al., 2003). The work on the tailings management areas was
completed in 1996 and the discharge from the tailings has been constantly monitored to ensure the
discharge standards are met.
6-8
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SCOTT WILSON RPA
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The tailings areas are regulated through a Uranium Mine Decommissioning Licence issued by the
Canadian Nuclear Safety Commission. Since mine closure in 1992, the facilities have remained in
compliance.
A comprehensive monitoring program termed the Serpent River Watershed Monitoring Program is
in place to measure and monitor the quality of the natural environment in the area of the Serpent
River watershed over time and assess the effectiveness of the tailings management programs on the
environment. The analysis of the data collected from the monitoring program demonstrates that the
tailings management programs have been successful (Ludgate et al., 2005).
HISTORIC MINERAL RESOURCE AND MINERAL RESERVE ESTIMATES
MINERAL RESOURCES
At the time the mine closed, Denison completed an estimate of the mineral resources and
mineral reserves remaining in the Mine. The information available that describes the estimation
method and lists the estimates is as follows:
|
|
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Copy of a memo titled Final Ore Reserves (Resources) 11 March 1992 by A. MacEachern
which describes the methods used to estimate the historic resources and reserves and the
documentation system used. |
|
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|
Seven 1 = 400 plans numbered 31-2044 to 31-2050 showing the location of the resource blocks
and the thickness and grade for each reef located in the block. (The resource tonnage and grade are
not listed.) |
|
|
|
|
Eighteen summary tables listing tonnage, grade/thickness, recovery factors, mining areas,
resource categories and cut-off grades. |
MINING AREAS AND REEF DESIGNATIONS
The Denison Mine was divided into Mining Areas 00 and 01 to 13. Mining Area 11 was the
Upper Zone. All other Mining Areas were on the Main Zone. Two of the 400-scale plans cover Upper
Zone (Mining Area 11) and the other five 400-scale plans cover the Main Zone (Mining Areas 00 to
10, and 13). The major portions of the historic resources are located in the Main Zone.
6-9
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SCOTT WILSON RPA
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The resources and reserves were estimated in 500 ft. by 500 ft. blocks to coincide with the
existing mine survey coordinate system. Each block was identified by a six digit number. The first
two digits are the Mining Area (these do not appear on the plans for space reasons). The second two
digits are the blocks north-south position (number increases from north to south). The last two
digits indicate the blocks west-east position (number increases from west to east). A block in the
Upper Zone has the same last four digits as the block beneath it in the Main Zone.
In the tables and plans, the reefs and quartzite layers are designated as UR, IQ, LR, and 3R.
From the hanging wall to the footwall, these acronyms designate the Upper Reef, Interbedded
Quartzite, Lower Reef and the Number 3 Bed, respectively. The Number 3 Bed (3R) occurs only over a
small area of the Stanrock Mine below the footwall of the LR. The plans list the individual reefs
and quartzite layers with the grade stated as lbs/ton U3O8.
Lower case letters ur, iq, and lr were used to denote the same reefs on the lower plate
of the Quirke Lake Overthrust Fault in Mining Areas 09, 10, and 13, Stanrock, CanMet and Canuc
blocks.
When necessary due to faults, diabase dykes, natural reef cut-offs, reef grade or thickness,
contamination from the Keyes diabase dyke or changes in Mining Area boundaries, the blocks were
subdivided. Each block segment is identified by a capital letter as shown on the plans. The
grades/thickness shown on the plans is a weighted average of all the block segments over the entire
block.
The resource tonnage and grade within each block are not listed on these plans, and tables are
not available showing the resource estimates by individual mining blocks. However, using the
tonnage factor and the reef thickness, the resource estimate for each reef for each individual
block can be determined.
6-10
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SCOTT WILSON RPA
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www.scottwilson.com |
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DRILLING
In the mined areas, 42,800 packsack diamond drill holes were drilled to delineate the
reefs. Drill hole spacing was usually 20 ft. to 40 ft. in most workings. Each hole, or pair of
holes, was drilled 2 ft. to 4 ft. above the hanging wall and below the footwall of the mining zone,
and chip samples were taken to complete the vertical section between holes. The core was broken
down by conglomerate and quartzite banding into sections of 0.25 ft. to 1.5 ft. and assayed. The
grade/thickness of each reef at each drill hole is the weighted average of all bands calculated to
the natural mining or reef hanging wall and footwall boundaries, corrected to vertical thickness.
Mining of the Upper Zone occurred only in later years. Before mining started, the Upper Zones
had been delineated by drilling up from the Main Zone on a spacing of 200 ft. to 300 ft. and from a
few surface diamond drill holes.
ESTIMATION METHODS
Sufficient pairs of co-ordinates to accurately establish the geometry of each block were
entered into a Dbase IV database to allow accurate calculation of the block areas. The mined areas
were digitized or planimetered to establish the mined-out area of each reef and, on the original
mine plans, the workings were colour coded to show the mined-out reef.
In another main file the grade/thickness, footwall elevation, dip, and mined-out area of each
applicable reef were entered. Each block was given a reporting filter to designate whether it was
developed, undeveloped, contaminated (by intrusion beside the Keyes dyke), or whether the block was
part of a party wall.
Because of the undulating reef dip, all tonnage calculations were done using vertical reef
thickness and areas calculated from horizontal plans. The tonnage factor used was 11.6 cubic feet
per short ton.
6-11
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SCOTT WILSON RPA
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www.scottwilson.com |
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The grade/thickness estimates were determined by averaging the grade/thickness of the
individual drill holes within the block. Adjustments were made based on underground observations of
grade/thickness changes and trends.
For the undeveloped resources, and especially for the outlying resources, where the drill hole
spacing was wider, the estimates of grade/thickness were based on extrapolation of the information
from the mined blocks.
CUT-OFF GRADES
Data sets were generated for the various reporting filters at six cut-off grades stated in
pounds per ton U3O8 for each Mining Area: 0.10, 0.80, 1.00, 1.50,
and 2.00. The data set totals were then tabulated and added using spreadsheets to produce summary tables showing
undiluted resources and reserves with 1.5 ft. of dilution grading 0.20 lb/ton
U3O8. The dilution factor of 1.5 ft. is an average figure
which varied with reef dip and thickness, and mining method.
|
|
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The 0.10 lb/ton U3O8 undiluted cut-off grade approximates the mining and
leaching of the complete orebody, including the Interbedded Quartzite. |
|
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|
The 0.80 lb/ton U3O8 undiluted cut-off grade represents the underground
leaching cut-off grade over the last years of production. It excludes the
Interbedded Quartzite. |
|
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|
The 1.00 lb/ton, 1.50 lbs/ton, and 2.00 lbs/ton U3O8
undiluted cut-off grades indicate the resources remaining for mining and
underground leaching at these cut-off grades, again excluding the Interbedded Quartzite. |
MINIMUM MINING WIDTH
The reef thickness was placed at the natural hanging wall and footwall boundaries. A
minimum mining thickness of six feet (1.8 m) was used for the historic resource estimate. Where the reef was less than six feet thick, it was diluted at a grade of 0.20 lb/ton
U3O8 to reach the six foot thickness.
6-12
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SCOTT WILSON RPA
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www.scottwilson.com |
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www.scottwilsonmining.com |
CLASSIFICATION
The mineral resources at the Denison properties were classified as Developed and
Undeveloped. Developed resources are those resources that have been developed for mining and in
which mining development has been driven, mining stopes have been excavated, and a portion of the
mineralization has been extracted. Undeveloped mineralization is located in blocks beyond existing
development workings where no mining has taken place.
MINING RECOVERY
The developed historical resources are further subdivided into resource remaining to be
mined in primary stopes and the resource remaining in pillars.
The primary mining assumes that 56% of the initial amount of the resource within the block can
be mined using the primary mining stoping layouts (refer to Figure 6-1). An estimate has been made
of the amount of the resource that could be mined from the pillars to bring the total extraction in
the block up to 70% of the initial amount of mineralization within the block (refer to Figure 6-1).
SUMMARY TABLES
In the tables, the historic resources and reserves are listed by mining area, mining
zone, and reef. The reef thickness is listed and for the historic mineral resources classified as
Developed, the percentage mined is provided. The historic resources and reserves are summarized by
classification and cut-off grade.
In the summary tables on the spreadsheets, an entry is included labelled S. AMER. This entry
refers to the Rio Algom-owned Spanish American mine designated by Denison as Mining Area 14. In the
mid-1980s, Denison tried unsuccessfully to acquire this property for its favourable grade and
proximity to the Denison No 2 shaft. The Spanish American mine was included because the reserves at
this mine could have a major influence on any decision to reopen the Denison Mine. Scott Wilson RPA
does not discuss this historic resource estimate in this report because it lies outside the Denison
Mine property boundary.
6-13
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SCOTT WILSON RPA
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www.scottwilson.com |
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www.scottwilsonmining.com |
The spreadsheets also list estimates at the 0.10 lb/ton cut-off grade for contaminated
mineralization and mineralization contained within designated boundary pillars. The contaminated
mineralization is located adjacent to diabase dykes and exhibits chlorite alteration as a result
of the intrusion. The chlorite alteration caused operational problems in the milling due to the
increased acid consumption and filtering problems. These resources are only listed at the 0.10
lb/ton cut-off grade and they are not included in the summary tables shown in this report.
The summary of the Developed and Undeveloped mineralization remaining at the Denison Mine is
shown in Table 6-2. Tables 6-3 and 6-4 list the cut-off grade in lbs/ton
U3O8, the percentage mined, the mineralization remaining that can be
extracted using the
primary mining method, the additional mineralization remaining that can be extracted from the
pillars, and the total mineralization remaining in the mine. The total resource remaining would
represent 100% extraction. Scott Wilson RPA estimated the total resource remaining in the ground
based on the percentage mined and the mining recovery.
For example, at the 0.01 lb/ton U3O8 cut-off grade for the
Developed resource, the
total amount mined is 18.5% of the original resource present prior to mining. The total
initial resource in the ground is estimated at 141.6 million tons. The total mined is 0.185 times
141.6, or 26.2 million tons, and 115.4 million tons remain in the ground as primary mining stopes
and pillars. The overall grade is estimated assuming that the grade of the mineralization remaining
in the pillars is the same as the grade applied to the portion of the pillar planned for
extraction.
For the undeveloped resource, the total tonnage of the resource remaining in the ground is
calculated based on the tonnage stated as representing a mining recovery of 70%. The grade is
assumed to be the same as the grade estimate at 70% extraction.
6-14
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SCOTT WILSON RPA
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www.scottwilson.com |
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www.scottwilsonmining.com |
The total resource in the ground does not include material in remnant pillars that remain in
blocks where the resource has been previously extracted to the 70% mining recovery limit.
TABLE 6-2 MINERALIZATION DEVELOPED AND UNDEVELOPED
Denison Mines Corp. Elliot Lake
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total Primary & |
|
Total |
|
|
|
|
|
|
Primary Mining |
|
Pillar Mining |
|
Pillar Mining |
|
Mineralization |
|
|
|
|
|
|
Remaining |
|
Remaining |
|
Remaining |
|
Remaining |
Cut-off |
|
% |
|
Tons |
|
lb/ton |
|
Tons |
|
lb/ton |
|
Tons |
|
lb/ton |
|
Tons |
|
lb/ton |
lb/ton |
|
Mined |
|
M |
|
U3O8 |
|
M |
|
U3O8 |
|
M |
|
U3O8 |
|
M |
|
U3O8 |
|
0.01
|
|
|
9.9 |
|
|
|
125.5 |
|
|
|
0.96 |
|
|
|
42.8 |
|
|
|
1.17 |
|
|
|
168.3 |
|
|
|
1.01 |
|
|
|
244.7 |
|
|
1.05 |
0.80
|
|
|
14.0 |
|
|
|
79.1 |
|
|
|
1.17 |
|
|
|
31.1 |
|
|
|
1.39 |
|
|
|
110.2 |
|
|
|
1.23 |
|
|
|
169.7 |
|
|
1.21 |
1.00
|
|
|
17.5 |
|
|
|
54.5 |
|
|
|
1.30 |
|
|
|
24.5 |
|
|
|
1.54 |
|
|
|
78.9 |
|
|
|
1.37 |
|
|
|
115.9 |
|
|
1.40 |
1.25
|
|
|
27.1 |
|
|
|
20.3 |
|
|
|
1.39 |
|
|
|
14.5 |
|
|
|
1.84 |
|
|
|
34.9 |
|
|
|
1.68 |
|
|
|
50.7 |
|
|
1.69 |
1.50
|
|
|
35.7 |
|
|
|
7.4 |
|
|
|
1.87 |
|
|
|
9.2 |
|
|
|
2.13 |
|
|
|
16.6 |
|
|
|
2.01 |
|
|
|
30.1 |
|
|
2.05 |
2.00
|
|
|
41.9 |
|
|
|
2.0 |
|
|
|
1.73 |
|
|
|
4.3 |
|
|
|
2.45 |
|
|
|
6.3 |
|
|
|
2.39 |
|
|
|
14.9 |
|
|
2.33 |
TABLE 6-3 MINERALIZATION DEVELOPED
Denison Mines Corp. Elliot Lake
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total Primary & |
|
Total |
|
|
|
|
|
|
Primary Mining |
|
Pillar Mining |
|
Pillar Mining |
|
Mineralization |
|
|
|
|
|
|
Remaining |
|
Remaining |
|
Remaining |
|
Remaining |
Cut-off |
|
% |
|
Tons |
|
lb/ton |
|
Tons |
|
lb/ton |
|
Tons |
|
lb/ton |
|
Tons |
|
lb/ton |
lb/ton |
|
Mined |
|
M |
|
U3O8 |
|
M |
|
U3O8 |
|
M |
|
U3O8 |
|
M |
|
U3O8 |
|
0.01
|
|
|
18.5 |
|
|
53.1 |
|
1.01 |
|
|
24.7 |
|
|
1.38 |
|
|
77.8 |
|
|
1.12 |
|
|
115.4 |
|
|
1.20 |
0.80
|
|
|
24.0 |
|
|
33.7 |
|
1.20 |
|
|
19.6 |
|
|
1.55 |
|
|
53.3 |
|
|
1.32 |
|
|
89.2 |
|
|
1.29 |
1.00
|
|
|
28.5 |
|
|
22.9 |
|
1.34 |
|
|
16.6 |
|
|
1.69 |
|
|
39.5 |
|
|
1,48 |
|
|
59.6 |
|
|
1.55 |
1.25
|
|
|
35.7 |
|
|
9.7 |
|
1.61 |
|
|
11.6 |
|
|
1.94 |
|
|
21.3 |
|
|
1.78 |
|
|
31.1 |
|
|
1.83 |
1.50
|
|
|
43.7 |
|
|
7.4 |
|
2.02 |
|
|
9.2 |
|
|
2.19 |
|
|
11.3 |
|
|
2.14 |
|
|
22.5 |
|
|
2.16 |
2.00
|
|
|
44.7 |
|
|
1.3 |
|
2.39 |
|
|
4.2 |
|
|
2.45 |
|
|
5.6 |
|
|
2.43 |
|
|
10.2 |
|
|
2.44 |
6-15
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SCOTT WILSON RPA
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www.scottwilson.com |
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TABLE 6-4 MINERALIZATION UNDEVELOPED
Denison Mines Corp. Elliot Lake
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total Primary & |
|
Total |
|
|
Primary Mining |
|
Pillar Mining |
|
Pillar Mining |
|
Mineralization |
|
|
Remaining |
|
Remaining |
|
Remaining |
|
Remaining |
Cut-off |
|
Tons |
|
lb/ton |
|
Tons |
|
lb/ton |
|
Tons |
|
lb/ton |
|
Tons |
|
lb/ton |
lb/ton |
|
M |
|
U3O8 |
|
M |
|
U3O8 |
|
M |
|
U3O8 |
|
M |
|
U3O8 |
|
0.01
|
|
|
72.4 |
|
|
|
0.92 |
|
|
|
18.1 |
|
|
|
0.92 |
|
|
|
90.5 |
|
|
|
0.92 |
|
|
|
129.3 |
|
|
|
0.92 |
|
0.80
|
|
|
45.1 |
|
|
|
1.13 |
|
|
|
11.3 |
|
|
|
1.13 |
|
|
|
56.3 |
|
|
|
1.13 |
|
|
|
80.5 |
|
|
|
1.13 |
|
1.00
|
|
|
31.6 |
|
|
|
1.24 |
|
|
|
7.9 |
|
|
|
1.13 |
|
|
|
39.4 |
|
|
|
1.24 |
|
|
|
56.3 |
|
|
|
1.24 |
|
1.25
|
|
|
11.0 |
|
|
|
1.48 |
|
|
|
2.8 |
|
|
|
1.48 |
|
|
|
13.8 |
|
|
|
1.48 |
|
|
|
19.6 |
|
|
|
1.48 |
|
1.50
|
|
|
4.3 |
|
|
|
1.74 |
|
|
|
1.1 |
|
|
|
1.74 |
|
|
|
5.3 |
|
|
|
1.74 |
|
|
|
7.6 |
|
|
|
1.74 |
|
2.00
|
|
|
2.6 |
|
|
|
2.08 |
|
|
|
0.7 |
|
|
|
2.08 |
|
|
|
0.9 |
|
|
|
2.02 |
|
|
|
4.7 |
|
|
|
2.08 |
|
HISTORIC RESERVES
The computer generated tables also show the resource that was classified as reserves at the
time that the mine was closed. The historic reserves are based on the mining methods, conversion
factors, metallurgical recoveries, and economic parameters used during the former production
period. The historic reserves were derived using a minimum
mining width of 6 ft. (1.8 m), with 1.5 ft. added at a grade of 0.20 lb/ton
U3O8 .
The reserve estimates are not listed since the historic resources would have to be
re-estimated using appropriate technical parameters and updated economic factors.
HISTORIC VALIDATION OF ESTIMATES
Once each month the Denison assay laboratory sent a blind sample to other laboratories,
including Rio Algom and Atomic Energy Canada Ltd., and assayed a blind sample from each of these
facilities in return. MacEachern (1991) reported the assay results for a period of eighteen years
and all laboratory results were virtually identical to the second decimal place.
6-16
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SCOTT WILSON RPA
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www.scottwilson.com |
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|
www.scottwilsonmining.com |
Unusually high or nugget effect-type analyses were not common. A check assay would be
requested and, if the result was still high compared to the log description, the assay would be
cut.
Over the 35 years of production at Denison, the correlation between geology predicted grades
and actual mill production grades was characterized as very good (MacEachern, 2007).
6-17
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7 GEOLOGICAL SETTING
REGIONAL GEOLOGY
The Elliot Lake area lies within the Precambrian Canadian Shield of Northern Ontario,
Canada, on the boundary between the Southern and Superior Geological Provinces. The Southern
Province extends from the Sault Ste. Marie area on the west to the Cobalt area on the east and
consists primarily of a thick sequence of clastic sediments with minor sequences of marine
limestone and extrusive volcanic rocks. The clastic sequence is referred to as the Huronian
Supergroup and these sediments were deposited in the early Proterozoic (2450 Ma to 2115 Ma) on
Archean-aged metavolcanic and metasedimentary rocks and granitic intrusive rocks of the Superior
Province. The majority of the uranium occurrences are hosted in the lower portion of the Matinenda
Formation.
The Huronian sediments were intruded by sills and dykes of the Nipissing diabase that are
dated at 2115 Ma (millions of years). The sediments and diabase intrusions were deformed and
metamorphosed during the Penokean orogeny (1850 to 1750 Ma), which resulted in folding and thrust
faulting.
In the Elliot Lake area, the Huronian rocks are folded to form a shallow westward plunging,
gently folded syncline designated as the Quirke syncline. The Quirke syncline is flanked on the
north and east by Archean granites and on the south by Archean mafic metavolcanic and
metasedimentary rocks. The limbs of the Quirke syncline generally dip from 10o to
40o towards its axis.
The major fault mapped within the immediate Elliot Lake District is the Flack Lake fault,
which is located immediately north of the Quirke Lake syncline. The thrust fault
strikes parallel with the strike of the bedding and dips south at an angle slightly steeper
than the strike of the bedding. The movement on the fault is south side up and the amount of
movement was estimated at 400 m.
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Thrust faults also occur within the Denison Mine environment. The Quirke Lake overthrust fault
is located in the hanging wall of the deposit. The south side of the fault has been thrust over the
north side and the fault offsets the Nippissing diabase dykes and the conglomerate beds. A second
unnamed thrust fault is shown on the mine longitudinal section. This fault is located directly
above the conglomerate beds in the Pecors argillite. The fault offsets the Nipissing diabase and
the sediments.
The thrust faults are a district-wide feature. Robertson (1962) describes the Whiskey Lake and
the Batty Lake thrust faults on the south limb of the syncline which exhibit similar orientation
and movement and probably formed during the same orogenic period as the Flack Lake Fault and the
thrust faults at the Denison Mine.
Although the coarser grained quartzite beds in the lower Matinenda Formation commonly contain
low-grade uranium mineralization, the higher grade uranium mineralization is hosted within the beds
of quartz-pebble conglomerate with disseminated pyrite in the matrix. In general, the uranium grade
increases with increasing pyrite content. The uranium-bearing conglomerate beds are found within
thicker sections of the Matinenda Formation that are located over depressions in the underlying
basement. The Matinenda Formation has been divided into two members. The lower member, referred
to as the Ryan Member, hosts the uranium deposits. The Stinson Member consists of massive quartzite
beds.
The thicker sections of the Ryan Member are termed channels and the channels generally strike
west-northwest. Figure 7-1 shows the location of the channels along the flanks of the Quirke
syncline. The Denison Mine is located within the Quirke channel. The Quirke channel also contained
the Quirke, Panel, Spanish American, and Stanrock Mines.
Although the Matinenda Formation is generally deposited on the Archean basement, it has been
deposited locally on Huronian volcanic formations (the Livingston Creek Formation) at the south
margin of the Quirke syncline.
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TABLE 7-1 HURONIAN SUPERGROUP, ELLIOT LAKE AREA
Denison Mines Corp. Elliot Lake
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|
|
|
|
Formation |
|
Member |
|
Description |
Cobalt Group |
|
|
|
|
|
|
|
|
|
Gowganda Formation
|
|
|
|
Conglomerate |
|
|
|
|
|
Quirke Lake Group |
|
|
|
|
|
|
|
|
|
Serpent Formation
|
|
|
|
Feldspathic quartzites |
|
|
|
|
|
Espanola Formation
|
|
|
|
Argillite |
|
|
|
|
|
Bruce Formation
|
|
|
|
Thinly bedded limestone and siltstone, more massive
limestone in upper beds Thickness varies from 50 ft.
to 120 ft |
|
|
|
|
|
Hough Lake Group |
|
|
|
|
|
|
|
|
|
Mississagi Formation
|
|
|
|
Grey quartzite and feldspathic quartzite, well bedded,
forms scarps, gradational contact with Pecors
(interbanded) cross bedding shows currents from NW |
|
|
|
|
|
Pecors Formation
|
|
|
|
Argillite and Greywacke, graded bedding |
|
|
|
|
|
Ramsey
Lake Formation
|
|
|
|
Varies in thickness from 5 to 200 Contact is sharp with McKim, but does overlap on the basement |
|
|
|
|
|
Elliot Lake Group |
|
|
|
|
|
|
|
|
|
McKim Formation
|
|
|
|
Banded greywacke and argillite, locally termed
Nordic Formation Cross bedding indicates beds
were deposited from the NW |
|
|
|
|
|
Matinenda Formation
|
|
Stinson
|
|
Massive grey quartzite with minor pebble beds and
coarse-grained grit |
|
|
|
|
|
|
|
Ryan
|
|
Coarse-grained quartzite or arkose, pebble bands,
and quartz-pebble conglomerates bands, sericitic
alteration with distinctive green colour |
|
|
|
|
|
|
|
Basal
Conglomerate
or Breccia
|
|
Quartz pebbles and fragments of basement rocks,
pyrite and pyrrhotite in matrix, often contains uranium
mineralization |
|
|
|
|
|
Livingston Creek
|
|
|
|
Local mafic volcanic with interbanded sediments |
Archean Basement Rocks Metavolcanics, Metasediments, Iron Formation and Granite
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PROPERTY GEOLOGY
The uranium mineralization is contained within two zones, the Main Zone and the Upper
Zone, and each zone contains multiple conglomerate beds. The zones consist of two sets of
uraniferous, pyritic, quartz pebble conglomerate reefs. The Main Zone and the Upper Zone are
separated by 120 ft. of quartzite. The reefs strike from 105° to 120° and dip
from 0° to -60° south. Most of the remaining resources are contained within
reefs that dip from -10° to -20°.
Each reef consists of a number of bands of conglomerate and quartzite. Some bands can be
followed for considerable distances, while others pinch and swell and are cut off by cross bedding
over relatively short distances. The better grade reefs have a minimal number of thinner quartzite
bands, well packed thicker conglomerate bands, and coarser pyrite.
A north-south cross-section through the Denison Mine showing the location of the Main and
Upper Zones and the reefs is shown in Figure 7-2.
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Main Zone
Most of Denisons production and remaining resources are in the Main Zone. In the tables and
plans provided, and discussed under Item 6 History, the units within the Main Zone are designated
UR, IQ, LR, and 3R. These are from hanging wall to footwall; the Upper Reef, the Interbedded
Quartzite, the Lower Reef, and the Number 3 Bed. Lower case letters ur, iq, and lr are used to
denote the same reefs on the lower plate of the Quirke Lake Overthrust Fault at Mining Areas 09,
10, and 13, Stanrock, CanMet and Canuc.
From north to south across the deposit, two very important gradual trends are evident. The IQ
thickens from less than one foot to as much as 12 ft. and the UR divides into three units, the
Hanging Upper (HU), Quartzite (Q), and Basal Upper (BU), with a resulting significant drop in
grade. The Number 3 Bed (3R) occurs only over a small area of the Stanrock Mine below the footwall
of the LR.
Upper Zone
There are two Upper Zone reefs FR, the F reef, and ER, the E reef. The 400 scale
plans show the grade and thickness of the quartzite separating these reefs. Generally, the E
reef is thicker, and the F reef was not mined. To the north of the Denison Mine Property at the
former Rio Algom Quirke Mine, these reefs graded significantly higher at 2 lbs/ton to 4 lbs/ton U3O8. There are a number of areas where the
reefs in the Upper Zone are not present because one or both reefs are cut off or scoured away by the overlying
Pecors argillite.
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8 DEPOSIT TYPES
The Elliot Lake deposits are interpreted to be modified paleoplacer deposits and the
source rocks are believed to be pegmatitic granite (Robertson 1986) located to the north. The
uranium was released from the granites as a result of weathering and transported as uraninite to
the site of deposition in channel systems in sedimentary basins formed in the Early Proterozoic.
With the current oxygen content of the atmosphere, the uranium minerals would oxidize and dissolve
in the ground water and be transported in solution. It is suggested that the erosion and
sedimentation took place in the early Proterozoic in a reducing environment as a result of the low
oxygen content of the atmosphere prior to 2200 Ma. The uranium was transported as heavy mineral
grains along with quartz pebbles, pyrite, and other heavy minerals, such as zircon, rutile,
leucoxene and monazite, in fast flowing streams within topographic lows in the Archean bedrock.
The quartz pebbles and the uranium and associated heavy minerals were deposited in areas where
the velocity of the streams was reduced, forming conglomerate beds in deltaic piles. Peripheral to
the conglomerate beds, poorly sorted feldspathic sand and silt were deposited. The character of
these peripheral sediments is indicative of wave action on delta margins and offshore deep water
conditions (Robertson 1986). Subsequent diagenesis resulted in the formation of the conglomerate
beds intercalated within coarse sandstone with scattered pebbles and siltstone. At the Denison
Mine, the highest grade uranium mineralization occurred to the lee of basement highs where the flow
was more abruptly reduced (A. MacEachern, personal communication).
Robinson and Spooner (1984) suggest that post-depositional modification of the uranium
occurred in three stages. The first involved leaching of iron from detrital ilmeno-magnetite grains
and mobility of uranium, thorium, rare earth elements and silica. Uraninite was replaced by
coffinite, quartz and detrital monazite were altered to urano-
thorite, and uranium reacted with TiO2 to form brannerite. The next two stages
involved the precipitation of secondary pyrite and the formation of secondary quartz and sericite.
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They suggest that this post-depositional modification was caused by low Eh near-neutral ground
water.
It appears that the post-depositional modification of the detrital uranium has been limited
within the conglomerate beds and the uranium has not been transported any great distances. There is
no indication of the formation of major secondary uranium deposits during the period when these
deposits were explored and mined.
The exploration model at Elliot Lake consists of drilling the lower Matinenda Formation to
test and outline the quartz pebble conglomerate beds based on the modified paleoplacer model.
However, any exploration program at Elliot Lake should also consider the potential for secondary
enrichment deposits resulting from the interaction of ground water with either hydrothermal fluids
or iron-rich rocks. Jefferson et al. (2004) have indicated that several paleo and Mesoproterozoic
basins in Canada, including the Huronian Basin, are considered to have potential for
unconformity-related uranium deposits. A recent press release by Pele Mountain Resources Inc. (May
7, 2007) described higher-grade uranium mineralization with secondary uranium minerals at Elliot
Lake located at the base of the Matinenda Formation within a basal conglomerate bed. This
mineralization may be related to faulting, that cross-cuts the Huronian sediments and the
underlying basement rocks.
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9 MINERALIZATION
The uranium-bearing minerals, uraninite and brannerite, along with pyrite, and other
heavy minerals, occur in the matrix of the conglomerate interstitial to the quartz pebbles. The
primary uranium-bearing minerals and accessory heavy minerals are listed in Table 9-1. The hardness
and specific gravity of these minerals are also shown. The uraninite is generally concentrated at
the base of the conglomerate beds with the largest pebbles, whereas the brannerite, rutile,
monazite, and zircon are more concentrated in the upper portion of the beds.
Microprobe work confirmed the existence of a continuous mineral series recognized optically,
which ranges from uranium-free leucoxene/rutile to uranium enriched brannerite. Secondary uranium
minerals coffinite, thucolite, and pitchblende have been reported from the district, but not
from the Denison Mine. Theis (1979) reported that the uranium in the Denison Mine is primarily
associated with brannerite and uraninite. Theis reported the following analysis: 65%
UO2; 6.5% ThO2; 18% PbO and
2.5% Y2O3, with less than 1% Ce2O3. The brannerite
is associated with other titaniferous
phases (rutile). Theis recognized two types of brannerite that were texturally distinct.
Based on 23 microprobe analyses by Theis, Type 1 grains averaged 47.3% TiO2,
30.7% UO2, 5.9% SiO2, 1.13% Nb2O3, 1.08%
Ce2O3, 0.89% ThO2, 0.68% CaO, and 0.43%
Y2O5. Based on 12 microprobe analyses, Type 2 brannerite grains averaged
36.6% UO2, 36.0% TiO2, 5.1% CaO, 3.0% SiO2, 1.7%
Y2O5, 0.7% Ce2O3 and 0.6% ThO2.
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TABLE 9-1 URANIUM-BEARING AND ASSOCIATED HEAVY MINERALS
Elliot Lake Camp
Denison Mines Corp. Denison Mine Property
|
|
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|
|
|
|
|
|
|
|
|
|
Specific |
|
|
|
|
Mineral |
|
Formula |
|
Gravity |
|
Hardness |
|
Comments |
|
Uraninite |
|
UO2 |
|
7.5 9.7 |
|
5.5 |
|
65% UO2, AccessoryTh, |
|
|
|
|
|
|
|
|
Pb, Ce, Y |
|
|
|
|
|
|
|
|
|
Brannerite |
|
(U,
Ca, Ce)(Ti, Fe)2O6 |
|
5.4 |
|
4 5 |
|
30 to 36% UO2, Ti, Si, |
|
|
|
|
|
|
|
|
Th, and REE |
|
|
|
|
|
|
|
|
|
Monazite |
|
(Ce, La, Nd, Y, Th)PO4 |
|
4.6-5.4 |
|
5.0 5.5 |
|
Contains trace |
|
|
|
|
|
|
|
|
UO2, dominant REE |
|
|
|
|
|
|
|
|
|
Pyrite |
|
FeS2 |
|
5.0 |
|
6.0 6.5 |
|
Primary and secondary |
|
|
|
|
|
|
|
|
Py noted |
|
|
|
|
|
|
|
|
|
Rutile |
|
TiO2 |
|
4.2 |
|
6.0 6.5 |
|
Occurs as composite |
|
|
|
|
|
|
|
|
grains with brannerite |
|
|
|
|
|
|
|
|
|
Zircon |
|
ZrSiO4 |
|
4.6 |
|
7.5 |
|
Occurs with monazite |
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10 EXPLORATION
Denison has not conducted any new exploration on the Denison Mine Property since
the mine was closed in 1992.
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11 DRILLING
There has not been any new drilling on the Denison Mine Property since the mine was
closed in 1992.
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12 SAMPLING METHOD AND APPROACH
There has not been any sampling done on the property since the mine was closed in
1992.
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13 SAMPLE PREPARATION, ANALYSES AND SECURITY
This item is not applicable.
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14 DATA VERIFICATION
This item is not applicable.
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15 ADJACENT PROPERTIES
Scott Wilson RPA is not aware of any information from adjacent properties that was
used to prepare the historical resource estimates.
The Denison Mine Property is located directly adjacent to the Spanish American Mine which
was owned by Rio Algom Limited, now BHP Billiton. This deposit is located proximal to the
Denison No 2 Shaft.
Denison also has several claims located directly west of the Denison Mine Property. These
claims do not contain any portion of the historical resource estimates discussed in this report,
however, wide-spaced drilling indicates that the claims do contain the favourable conglomerate
beds. The exploration potential of these claims is discussed briefly in Item 20.
The locations of the additional Denison properties and the Spanish American property are
shown in Figure 15-1.
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16 MINERAL PROCESSING AND
METALLURGICAL TESTING
The metallurgical processing methods used and the metal recoveries achieved during
the former operations are described under Item 6 History. There has not been any new test work
conducted on the metallurgy since the mine was closed.
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17 MINERAL RESOURCE AND MINERAL
RESERVE ESTIMATES
No mineral resources or reserves were estimated by Scott Wilson RPA for the purposes
of this report.
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18 OTHER RELEVANT DATA AND
INFORMATION
FIRST NATIONS AND NORTH SHORE COMMUNITIES
The Serpent River First Nation and the village of Spragge are located in the southern
portion of the Serpent River drainage basin near the outlet of the river into Georgian Bay. In
addition to Elliot Lake, these communities could be affected by any future mine or plant
development and operations.
The First Nations also have traditional hunting and fishing rights in the Serpent River
Basin and they are an important stakeholder in any project in the area. They expressed many
concerns during the public hearings held following the closure of the mines to determine the
tailings management plans in the Elliot Lake camp (Kirkwood, 1996).
EXPLORATION POTENTIAL
In the memo of October 9, 1991, MacEachern discusses the exploration potential of Denisons
Elliot Lake Properties (MacEachern 1991).
Much of the property originally held by Denison in 1991 has been released by Denison and
many of the claims are covered under the FND status. A new review would have to be conducted on
the properties currently held.
The claim blocks located to the south and southeast of the Stanrock property have been
dropped and recently restaked by other interests. Based on MacEacherns discussion (1991), the
conglomerate beds hosting the mineralization in the Denison and Stanrock Mines continued into
these claim blocks, but drilling suggested that the grades were low. However, the drilling was
very limited in this area.
Denisons current holdings outside of the Denison and Stanrock Mines are primarily located
to the west of these properties and extend to Dunlop Lake. MacEachern suggested that a western
branch of the Denison Main Zone reefs may exist in this area and
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recommended further exploration. Two holes were drilled in the area in 1985 and the second
hole established that the reef was present approximately 7,000 ft. to the west of previous holes
that had been previously interpreted as the edge of the mineralization. No further drilling was
conducted in this area.
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19 ADDITIONAL REQUIREMENTS
The Denison Mine Property is not in the development or production stage and there
are no requirements under this item.
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20 INTERPRETATION AND CONCLUSIONS
The uranium mineralization is contained within quartz-pebble conglomerate beds that
vary in thickness from about five feet up to twelve feet. The conglomerate beds or reefs, are
contained within two zones, the Main Zone and the Upper Zone, and each zone contains multiple
conglomerate beds separated by barren quartzite beds. The Main Zone and the Upper Zone are
separated by 120 ft. of quartzite.
The historic resources were estimated using classical polygonal methods in 500 ft. by 500
ft. blocks. The grade and thickness of the individual conglomerate beds were estimated by
averaging the grade/thickness of the individual drill holes within the block. In the mined areas,
packsack diamond drill holes and chip sampling were used. Adjustments were made to the grade and
thickness based on underground observations of grade/thickness changes and trends. For the
undeveloped resources, and especially for the outlying resources, where the drill hole spacing
was wider, the estimates of grade/thickness were based on extrapolation of the information from
the mined blocks.
A minimum bed thickness of six feet was used for resource estimation. Where the
bed was less than six feet, it was diluted at a grade of 0.20 lb/ton
U3O8 to reach the six-
foot thickness. The tonnage factor used was 11.6 ft.3/ton.
The areas that had been mined were digitized or planimetered to calculate the mined-out
area of each reef, and the mined area was not included in the resource estimate.
The mineral resource estimates were classified as Developed and Undeveloped. Developed
resources are those resources that have been developed for mining and remain after partial
mining. Undeveloped resources are located in blocks beyond existing development workings where
no mining has taken place.
The resources were further subdivided into primary mining and pillar mining
representing 56% and 70%, respectively, of the total resource available after subtracting
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mining removal. Resources identified as being contaminated (by intrusion beside the
Keyes dyke), or contained within a block that was part of a party wall, were not included.
The historic resource estimates were determined at cut-off grades of 0.1 lb/ton, 0.8 lb/ton,
1.0 lb/ton, 1.25 lbs/ton, 1.5 lbs/ton, and 2.0 lbs/ton
U3O8.
Table 20-1 lists the historic estimate of the resource remaining, using the historic
categories, at a cut-off grade of 0.80 lb/ton
U3O8
(0.04%
U3O8). A mining recovery of 56% was used for
the primary mining stage and 70% for primary plus secondary (pillar) mining. The total resource
remaining is also listed. The total resource remaining represents 100% of all the mineralization
without applying any mining recovery factors. For consistency with current reporting standards
for mineral resources, Scott Wilson RPA recommends that the historic resource estimates also be
reported without applying mining recovery factors.
The historic resource estimates are based on the technical and economic parameters used by
Denison at the time of the mine closure in 1992 and do not reflect current technical and economic
parameters. Scott Wilson RPA recommends that the historic resource estimate be reported using a
0.80 lb/ton cut-off grade which represents the undiluted cut-off grade for the underground
leaching over the last years of production and excludes the Interbedded Quartzite unit.
20-2
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TABLE 20-1 HISTORIC RESOURCE DEVELOPED AND
UNDEVELOPED DENISON MINE
Denison Mines Corp. Elliot Lake
|
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|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Primary |
|
|
|
|
|
|
|
|
|
Total Primary & |
|
Total |
|
|
|
|
|
|
Mining |
|
Pillar Mining |
|
Pillar Mining |
|
Mineralization |
|
|
|
|
|
|
Remaining |
|
Remaining |
|
Remaining |
|
Remaining |
|
|
% |
|
Tons |
|
Lb/ton |
|
Tons |
|
Lb/ton |
|
Tons |
|
Lb/ton |
|
Tons, |
|
Lb/ton |
|
|
Mined |
|
M |
|
U3O8 |
|
M |
|
U3O8 |
|
M |
|
U3O8 |
|
M |
|
U3O8 |
|
Developed |
|
|
24.0 |
|
|
|
33.7 |
|
|
|
1.20 |
|
|
|
19.6 |
|
|
|
1.55 |
|
|
|
53.3 |
|
|
|
1.32 |
|
|
|
89.2 |
|
|
|
1.29 |
|
Undeveloped |
|
|
0 |
|
|
|
45.1 |
|
|
|
1.13 |
|
|
|
11.3 |
|
|
|
1.13 |
|
|
|
56.3 |
|
|
|
1.13 |
|
|
|
80.5 |
|
|
|
1.13 |
|
|
Total |
|
|
14.0 |
|
|
|
79.1 |
|
|
|
1.17 |
|
|
|
31.1 |
|
|
|
1.39 |
|
|
|
110.2 |
|
|
|
1.23 |
|
|
|
169.7 |
|
|
|
1.21 |
|
Notes:
|
1. |
|
CIM definitions are not used. |
|
|
2. |
|
Historic resource estimates are reported at cutoff grades of
0.8 lb/t
U3O8
(0.04%
U3O8). |
|
|
3. |
|
A minimum width of 6 feet was used. |
|
|
4. |
|
The total primary and pillar mining represents the estimated recoverable
resource based on the mining methods employed at the Denison Mine in 1992. |
|
|
5. |
|
The total mineralization remaining represents the total amount of mineral remaining
in the ground without applying mining recovery factors. |
|
|
6. |
|
The historic resource estimates cannot be verified and the estimates are not
necessarily indicative of the mineralization on the property. |
The mineral resource and mineral reserve estimates were conducted prior to the
effective date of National Instrument 43-101 on February 1, 2001, and do not conform to
disclosure requirements under the Instrument. No records of the borehole location, borehole
logs, sample assays, underground mapping, or surveys of the mine openings are available to
validate the estimates. Scott Wilson RPA has been unable to verify the resource estimates, and
notes that the historic estimates are not necessarily indicative of the mineralization on the
property that is the subject of the technical report.
In the opinion of Scott Wilson RPA, although the historic resource estimate cannot be
validated, the estimate is considered to be reasonable based on the estimation methods used at
the time. The historic resource estimate is not considered to be relevant to current economic
assessment parameters.
Mr. Alan MacEachern, in his memo to Scott Wilson RPA (2007), states that most developed
resources are in blocks where there are workings with complete diamond drill hole samples. He
indicates, however, that, in his opinion, some of the blocks lack sufficient drilling data to be
classified as measured. Since the detailed data supporting
20-3
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SCOTT WILSON RPA
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www.scottwilson.com |
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the original resource estimates are not available, it is not possible to verify the
portions of the Developed resource that could be classified as measured or the portions of the
Developed resource that could be classified as indicated. MacEachern also states that
Undeveloped resources beyond the workings are the equivalent of indicated and inferred
resources. Again, however, it is not possible to determine the portion of the Undeveloped
resource that could be classified as indicated or the portions of the Undeveloped resource that
would be classified as inferred.
In addition, there are other factors that affect the classification. For example poor
ground conditions, resulting in the deterioration of the pillars, could result in portions of
the resource being unrecoverable and, therefore, not qualified to be categorized as a mineral
resource.
In the opinion of Scott Wilson RPA, without access to the drilling information, the
historic resource cannot be classified directly under the CIM classification standards
incorporated under NI 43-101.
20-4
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SCOTT WILSON RPA
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www.scottwilson.com |
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21 RECOMMENDATIONS
Although the historic mineral resource estimate for the Denison Mine Property cannot
be validated, these estimates do provide sufficient information to carry out order-of-magnitude
economic assessments (pre-scoping level) to determine if additional exploration and evaluation
is warranted. As part of this study the following work is recommended:
|
|
|
Conduct a detailed review of the 400 scale plans to determine the distribution of the
mineral resources by reef and classification and outline mining blocks for mining
evaluation and scheduling. |
|
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|
|
Determine the mine production potential and schedule assuming similar mining methods as
those used at the time of closure. |
|
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|
|
Estimate mining costs, processing costs, tailings management costs, and administration
costs using similar mining and processing methods that were used at the time the mine
was closed. |
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|
Estimate the capital costs for the mine, processing plant, and services and tailings
management facilities. |
|
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|
|
Carry out an estimate on the amount of water in the mine and determine the amount of
U3O8 contained in the water to evaluate the
potential to extract U3O8 while the mine is being
dewatered. |
|
|
|
|
Conduct metallurgical tests on samples of the mine water to determine the uranium
content and recoveries. |
|
|
|
|
Conduct the order-of-magnitude economic assessment. |
COST ESTIMATE
|
|
A preliminary cost estimate for preparing a pre-scoping (conceptual) economic
assessment using the historic resource estimate and information available is provided in Table
21-1. |
21-1
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SCOTT WILSON RPA
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www.scottwilson.com |
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www.scottwilsonmining.com |
TABLE 21-1 PRE-SCOPING LEVEL COST ESTIMATE
Denison Mines Corp. Denison Mine Property
|
|
|
|
|
Item |
|
Comments |
|
Estimated Cost |
|
Resource Distribution |
|
Detailed assessment of 400-scale plans to |
|
$15,000 |
|
|
determine mining blocks |
|
|
|
|
|
|
|
Mine plan
and schedule |
|
Schedule blocks and determine mine |
|
$15,000 |
|
|
production rate |
|
|
|
|
|
|
|
Capex & Opex |
|
Assume previous production methods |
|
$ 15,000 |
|
|
|
|
|
Economic Evaluations |
|
|
|
$ 10,000 |
|
|
|
|
|
Metallurgical tests |
|
Extraction tests on mine water |
|
$ 20,000 |
|
|
|
|
|
Report |
|
|
|
$ 10,000 |
|
|
|
|
|
|
Total |
|
|
|
$ 85,000 |
21-2
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SCOTT WILSON RPA
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22 REFERENCES
Collins, W.H., 1925: The North Shore of Lake Huron; Geol. Surv. Canada, Mem. 143, 154 p.
Denison Mines Limited, 1998: 1988 Annual Report.
Economic Development Council, 2007: The City of Elliot Lake Community Profile.
Hedley, D.G.F.. M. Gangal and G. Morgan, 1983: Effect of Pillar Orientation on Stability,
Canadian Centre for Mineral and Energy Technology (CANMET) Elliot Lake Laboratory, Metals
Research Program, July 1983.
Jefferson, C., S. Gandhi, P. Ramaekers, G. Delaney, D. Thomas, C. Cutts, R. Olson, 2004:
Unconformity-Associated Uranium Deposits, Natural Resources Canada.
Kirkwood, D., McCreath, D., and Peters, T. 1996. Decommissioning of uranium mine tailings
management areas in the Elliot Lake area. Report of the Environmental Assessment Panel Laliberte,
R., Ludgate, I., and Knapp, R., 2003: Denison Mine 10 Years After Closure
Ludgate, I., Berthelot, D., and Russel, C., 2005: Presentation to Elliot Lake City Council.
MacEachern,
A.D., 1991: Elliot Lake Mining Claims and Land Tenures, a memo of October 9, 1991.
MacEachern, A. D., April 2007: RE: Request from Denison for Elliot Lake Resource Information.
Marchbank, A., Denison Mines Limited, 1986: Underground biological in-place leaching of uranium
ore.
Robertson, J.A., 1986: Huronian geology and the Blind River (Elliot Lake) uranium deposits in
Uranium Deposits of Canada, Special Volume 33, Canadian Institute of Mining and Metallurgy.
Robinson, A. G. and Spooner, E.T.C., 1984: Postdepositional modification of uraninite-bearing
quartz-pebble conglomerates from the Quirke ore zone, Elliot Lake, Ontario.
Roscoe, S. M., 1969: Huronian rocks and uraniferous conglomerates in the Canadian Shield; Geol.
Surv. Can., Paper 68-40.
Theis, N. J., 1979: Uranium-bearing and associated minerals in their geochemical and
sedimentological context, Elliot Lake Ontario. Geological Survey of Canada, Bulletin 304.
22-1
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SCOTT WILSON RPA
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www.scottwilson.com |
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www.scottwilsonmining.com |
23 SIGNATURE PAGE
This report titled Technical Report on the Elliot Lake Property, Elliot Lake
Ontario and dated June 29, 2007, was prepared and signed by the following authors:
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|
|
(Signed & Sealed)
|
|
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Dated at Toronto, Ontario |
|
|
|
|
June 29, 2007
|
|
Lawrence B. Cochrane, Ph.D., P.Eng. |
|
|
|
|
Principal Geologist |
|
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|
|
(Signed & Sealed) |
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|
|
Dated at Toronto, Ontario |
|
|
|
|
June 29, 2007
|
|
Leo R. Hwozdyk, P.Eng. |
|
|
|
|
Associate Mining Engineer |
|
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23-1
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SCOTT WILSON RPA
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www.scottwilson.com |
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www.scottwilsonmining.com |
24 CERTIFICATE OF QUALIFICATIONS
LAWRENCE B. COCHRANE
I, Lawrence B. Cochrane, P.Eng., as an author of this report entitled Technical Report on
the Elliot Lake Property, Elliot Lake District, Ontario prepared for Denison Mines Corp. and
dated June 29, 2007, do hereby certify that:
1. |
|
I am Principal Geologist with Scott Wilson Roscoe Postle Associates Inc. of Suite 501, 55
University Ave Toronto, ON, M5J 2H7. |
2. |
|
I am a graduate of Queens University at Kingston in 1969 a nd 1991 with a BSc in Applied
Science and a PhD in Geological Sciences respectively. |
3. |
|
I am registered as a Professional Engineer in the Province of Ontario, registration number
8801011. I have worked as a mining geologist for a total of 36 since my graduation. My
relevant experience for the purpose of the Technical Report is: |
|
|
|
Director of Mines Exploration and Qualified Person for Inco Limited, from 2001 to 2006 |
|
|
|
|
Superintendent of Mine Planning and Exploration for Inco Ontario Division, from 1991 to
1997. |
4. |
|
I have read the definition of qualified person set out in National Instrument 43-101
(NI43-101) and certify that by reason of my education, affiliation with a professional
association (as defined in NI43-101) and past relevant work experience, I fulfill the
requirements to be a qualified person for the purposes of NI43-101. |
|
5. |
|
I did not visit property. |
|
6. |
|
I am responsible for overall preparation of the Technical Report. |
|
7. |
|
I am independent of the Issuer applying the test set out in Section 1.4 of National
Instrument 43-101. |
|
8. |
|
I have had no prior involvement with the property that is the subject of the Technical
Report. |
|
9. |
|
I have read National Instrument 43-101, and the Technical Report has been prepared in
compliance with National Instrument 43-101 and Form 43-101F1. |
24-1
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SCOTT WILSON RPA
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www.scottwilson.com |
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www.scottwilsonmining.com |
10. |
|
To the best of my knowledge, information, and belief, the Technical Report contains
all scientific and technical information that is required to be disclosed to make the technical
report not misleading. |
Dated 29th day of June, 2007
(Signed & Sealed)
Lawrence B. Cochrane, Ph.D., P.Eng.
24-2
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SCOTT WILSON RPA
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www.scottwilson.com |
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|
www.scottwilsonmining.com |
LEO R. HWOZDYK
I, Leo R. Hwozdyk, P.Eng., as an author of this report entitled Technical Report on the
Elliot Lake Property, Elliot Lake District, Ontario prepared for Denison Mines Corp. and dated
June 29, 2007, do hereby certify that:
1. |
|
I am Associate Mining Engineer with Scott Wilson Roscoe Postle Associates Inc. of Suite
501, 55 University Ave Toronto, ON, M5J 2H7. |
|
2. |
|
I am a graduate of Queens University, Kingston, Ontario, in 1976 with a B.Sc in Mining. |
|
3. |
|
I am registered as a Professional Engineer in the Province of Ontario (Reg.# 21150016). I
have worked as a mining engineer for a total of 31 years since my graduation. My relevant
experience for the purpose of the Technical Report is: |
|
|
|
Review and report as a consultant on numerous mining operations and projects around
the world for due diligence and regulatory requirements. |
|
|
|
|
Mines Engineer at Denisons Elliot Lake Project. |
|
|
|
|
Mine Project Superintendent at various mines in Yukon and Ontario. |
4. |
|
I have read the definition of qualified person set out in National Instrument 43-101
(NI43-101) and certify that by reason of my education, affiliation with a professional
association (as defined in NI43-101) and past relevant work experience, I fulfill the
requirements to be a qualified person for the purposes of NI43-101. |
|
5. |
|
I visited the Denison Mine Property on May 29, 2007. |
|
6. |
|
I contributed to Item 6 (Historic Mining Methods) of the Technical Report. |
|
7. |
|
I am independent of the Issuer applying the test set out in Section 1.4 of National
Instrument 43-101. |
|
8. |
|
I have had no prior involvement with the property that is the subject of the Technical
Report. |
|
9. |
|
I have read National Instrument 43-101, and the Technical Report has been prepared in
compliance with National Instrument 43-101 and Form 43-101F1.
|
24-3
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SCOTT WILSON RPA
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www.scottwilson.com |
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www.scottwilsonmining.com |
10. |
|
To the best of my knowledge, information, and belief, the Technical Report contains
all scientific and technical information that is required to be disclosed to make the technical
report not misleading. |
Dated this 29th day of June, 2007
(Signed & Sealed)
Leo R. Hwozdyk, P.Eng.
24-4
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SCOTT WILSON RPA
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www.scottwilson.com |
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25 APPENDIX PROPERTY SITE VISIT
PHOTOS
25-1
Exhibit 3
|
|
|
|
|
Denison Mines Corp. Atrium on Bay,
595 Bay Street, Suite 402
Toronto, ON M5G 2C2
Canada
Tel : 416 979-1991
Fax: 416 979-5893
www.denisonmines.com |
PRESS RELEASE
DENISON INITIATES ORE BUYING PROGRAM FOR WHITE MESA MILL
Toronto, ON July 5, 2007... Denison Mines Corp. (Denison or the Company)
(DML:TSX,DNN: AMEX) is pleased to announce the start of a uranium ore buying program to
supplement feed for the Companys 100% owned White Mesa Mill in Utah. The White Mesa Mill
is a 2,000 ton per day dual circuit mill and is currently the only conventional uranium
mill operating in the U.S. Ore from the Companys mining operations in the U.S. is
currently being stockpiled at the Mill with processing scheduled to start in the first
quarter of 2008. The addition of purchased ore from third parties will maximize the
efficiency of this large capacity mill. The Company anticipates purchasing approximately
40,000 tons of uranium ore per year. The ore buying schedule for the month of July is
posted on the Companys website (www.denisonmines.com) and will be updated
monthly.
Ron Hochstein, President and COO of Denison, commented, This new ore buying program is
the first for the White Mesa Mill since 1998. With current all time high prices, the
uranium industry has been rejuvenated in the four corner states area with several mines
being re-opened, including the Companys. Denisons mill is the only operating one in a
500 mile radius in the heart of the historic uranium producing district in the U.S. and
we very much look forward to working with the independent miners in the region.
Denison Mines Corp. is a premier intermediate uranium producer in North America,
with mining assets in the Athabasca Basin Region of Saskatchewan, Canada and the
southwest United States including Colorado, Utah, and Arizona. Further, the Company has
ownership interests in two of the four uranium mills operating in North America today.
The Company also has a strong exploration portfolio with large land positions in the
United States, Canada and Mongolia. Correspondingly, the Company has one of the largest
uranium exploration teams among intermediate uranium companies.
Cautionary Statements
This news release contains forward-looking statements, within the meaning of the
United States Private Securities Litigation Reform Act of 1995 and similar Canadian
legislation, concerning the business, operations and financial performance and condition
of Denison Mines Corp. (Denison).
Forward looking statements include, but are not limited to, statements with respect to
estimated production; the development potential of Denisons properties; the future price
of uranium; the estimation of mineral reserves and resources; the realization of mineral
reserve estimates; the timing and amount of estimated future production; costs of
production; capital expenditures; success of exploration activities; permitting time
lines and permitting, mining or processing issues; currency exchange rate fluctuations;
government regulation of mining operations; environmental risks; unanticipated
reclamation expenses; title disputes or claims; and limitations on insurance coverage.
Generally, these forward-looking statements can be identified by the use of
forward-looking terminology such as plans, expects or does not expect, is
expected, budget, scheduled, estimates, forecasts, intends, anticipates or
does not anticipate, or believes, or variations of such words and phrases or state
that certain actions, events or results may, could, would, might or will be
taken, occur or be achieved.
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 cause the actual results, level of activity,
performance or achievements of Denison to be materially different from those expressed
or implied by such forward-looking statements, including but not limited to risks
related to: unexpected events during construction, expansion and start-up; variations in
ore grade, tonnes mined, crushed or milled; delay or failure to receive board or
government approvals; timing and availability of external financing
on acceptable terms; actual results of current exploration activities; conclusions of economic
evaluations; changes in project parameters as plans continue to be refined; future prices of
uranium and vanadium; possible variations in ore reserves, grade or recovery rates; failure of
plant, equipment or processes to operate as anticipated; accidents, labour disputes and other risks
of the mining industry; delays in the completion of development or construction activities, as well
as those factors discussed in or referred to under the heading Risk Factors in Denisons Annual
Information Form dated March 27, 2007 available at www.sedar.com and its Form 40-F
available at www.sec.gov. Although management of Denison has attempted to identify important
factors that could cause actual results to differ materially from those contained in
forward-looking statements, there may be other factors that cause results not to be as anticipated,
estimated or intended.
There can be no assurance that such statements will prove to be accurate, as actual results and
future events could differ materially from those anticipated in such statements. Accordingly,
readers should not place undue reliance on forward-looking statements. Denison does not undertake
to update any forward-looking statements that are incorporated by reference herein, except in
accordance with applicable securities laws. Mineral resources, which are not mineral reserves, do
not have demonstrated economic viability. Readers should refer to the Annual Information Form and
the Form 40-F of the Company for the fifteen month period ended December 31, 2006 and other
continuous disclosure documents filed since December 31, 2006 available at www.sedar.com, for
further information relating to their mineral resources and mineral reserves.
Cautionary Note to United States Investors Concerning Estimates of Measured, Indicated and
Inferred Resources: This news release uses the terms Measured, Indicated and Inferred
Resources. United States investors are advised that while such terms are recognized and required
by Canadian regulations, the United States Securities and Exchange Commission does not recognize
them. Inferred Mineral Resources have a great amount of uncertainty as to their existence, and
as to their economic and legal feasibility. It cannot be assumed that all or any part of an
Inferred Mineral Resource will ever be upgraded to a higher category. Under Canadian rules,
estimates of Inferred Mineral Resources may not form the basis of feasibility or other economic
studies. United States investors are cautioned not to assume that all or any part of Measured or
Indicated Mineral Resources will ever be converted into 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.
For further information, please contact:
|
|
|
|
|
E. Peter Farmer
|
|
(416) 979-1991 ext. 231
|
|
|
Ron Hochstein
|
|
(604) 689-7842 |
|
|
James Anderson
|
|
(416) 979-1991 ext. 372 |
|
|