SMDI #

1780

Historical Showing Names

JEB Open Pit, JEB Uranium Deposit

Project Name

McClean Lake

UTM Northing (NAD83 Z13)

6467957.9800

TRM (Township-Range-Meridian)

108-11-2

Associated Commodities

Arsenic, Graphite, Nickel

Status

Deposit: Post-Production

Geological Domain

Wollaston

Host Minerals

Arsenopyrite

Exploration History

7/14/1988 Work Done in Area: Regional mapping (Clarke & Fogwill 1981); Lake sed & water survey (74I01-0001); Grid WF (64L05-0043); Airborne EM & Radiometric survey (74I-0005,6,7). In 1962, the Gulf Minerals Permit No. 8 was covered by a joint federal-provincial airborne magnetic survey. In 1969, Gulf flew a airborne radiometric survey over the property and from 1969 to 1974, Gulf explored the Permit with reconnaissance surveys including a series of track etch surveys. In 1974, Gulf Minerals dropped Permit No. 8 and Can-Oxy flew a airborne reconnaissance survey over the former Permit. Can-Oxy staked anomalous areas with CBS 3501 to 3505. In 1975, Can-Oxy carried out a track etch survey over the claims - numerous anomalies were located. In the winter of 1976, five of the anomalies were drilled. Drill holes WOL-1-76 and 3-76 intersected 4 to 5 ft. of 0.09% U3O8 at the sandstone unconformity. Ground magnetic, Afmag and EM-16 surveys were completed over the Moffatt grid. In the summer of 1976, soil, bog, lake silt and lake water geochemical surveys were completed over the property. In 1977, airborne EM and magnetic surveys were flown and ground magnetic, VLF-EM and Afmag surveys were run over anomalous areas and 47 drill holes were completed over conductors located (drill holes WOL-27-77 intersected 1.0 ft. with 1270 ppm U3O8). A detailed alphameter survey was completed in the vicinity of this drill hole. In 1978, ground Max Min and VLEM surveys were run and the reconnaissance drilling program continued (45 drill holes). One hole intersected the Tent Zone.. This uraniferous zone (uraninite and zippeite) occurs in the regolith and is associated with basement graphitic semipelites, mylonite and complex, multistage chalcedony breccias with chlorite alteration. In 1979, several airborne radiometric surveys were flown and ground Max Min surveys were conducted. The program of reconnaissance drilling continued and resulted in the discovery of the Mallen Lake and McClean Lake zones (SMDI 1718, 1719). Mallen Lake Zone definition drilling was completed. In 1980, ground geophysics was continued, development drilling continued on the Mallen and McClean zones and 75 reconnaissance exploration holes were completed. In 1981, reconnaissance geophysical surveys and drilling continued - this resulted in the discovery of the "Candy Zone". In May of 1982, the drill program intersected the JEB Zone, which is located on the northeast corner of the Wallis grid. 5 drill holes intersected ore grades up to 9.72% U3O8 over 7.0 m. In 1983, the CBS converted to ML 5291. In 1985 to 1986, zone drilling was completed on the JEB Zone (AF 64L05-0117, 0118). In this year, a Canadian Occidental Petroleum and Canico joint venture completed environmental baseline studies, muskeg sampling and a clay content of boulders study (AF 64L05-0084) for the McLean deposits. In the winter of 1984, a Canadian Occidental Petroleum - Canico joint venture completed ground VLF-EM surveys over the Black, Misty and Snake (this grid is on strike with the Jeb Deposit) grids (AF 64L05-0085). In 1988, the partners completed a VLEM survey and percussion drill tested the east side of the JEB Zone (AF 64L05-0133). In 1989, the partnership completed 46 development and 13 exploration drill holes on the JEB Zone (AF 64L05-0134). The 1989 drill program, which failed to extend the size of the deposit, identified several high grade pockets within the orebody. In 1990, Minatco completed 13 geotechnical holes (PVS-1 to -5, R-165 to -172) on the JEB and McClean deposits (AF 64L05-0135). In 1991, Minatco completed ground VLF-EM and magnetic surveys and condemnation drill holes R-173 to -188 at the JEB Deposit (AF 64L05-0136). On 21 June, 1990, the deposit was staked as CBS 7656. In 1993, the Federal Environmental Assessment Review Office, studying the McLean Lake Deposit proposal for development, recommended that the project be put on hold. Late the same year, the Saskatchewan and Federal governments gave approval for the project to proceed. Late in 1994, surface stripping of the JEB pit commenced. In 1997, a ground IP/resistivity survey was completed on the JEB grid (AF 64L05-0138). In 1997, the JEB deposit was mined out using open pit techniques. The ore was stockpiled and will be processed at the McClean Project mill. It was announced that the 120 m (393.7 ft) deep JEB open pit would be commissioned as a two stage natural surround tailings management facility. The facility will hold tailings resulting from the processing of Sue Deposit ore. On 31 December 1997, Denison Mines Limited released an estimate of proved mineable reserves for the JEB Deposit. On 17 June 1999, the McClean operating licence, which was modified to include the JEB mill and tailings management facility, received AECB and SRM approval. On 22 June 1999, Cogema started to feed low grade (3%) stockpiled ore into the JEB mill grinding circuit. The first barrel of yellowcake was produced from JEB ore on 12 July 1999 and the first shipment of yellowcake occurred on 12 August 1999. In 2002, a partnership involving Cogema Resources (70%), Denison Mines Inc (22.5%) and OURD Canada (7.5%) flew an AeroTem survey that covered the deposit (AF 64L05-SW-0156). In 2003, the final stockpile of Sue ore was processed by the McCLean mill. Jeb ore is now exhausted.

Reserves and/or Resources

2003-12-31 Cogema – Denison 346 t U grading 0.42% U. Summary: Historic reserve (unspecified) of 346.00 tonne - Uranium: 346.00 tonne @ 0.42 % 1997-12-31 Proven mineable reserves of the JEB deposit: 71.8 thousand tonnes of ore which grades 3.29% U3O8 (5.2 million lbs U3O8). Summary: Historic proven reserve of 718,000.00 tonne - Uranium: 718,000.00 tonne @ 3.29 % 1985-01-01 Using a cut-off of 0.05% U3O8 over 2 m, the deposit was estimated to contain 4.65 million pounds of uranium oxide in ore with an average grade of 1.90% U3O8. Summary: Historic reserve (unspecified) of 4,650,000.00 lb - Uranium: 4,650,000.00 lb @ 1.9 %