NR March 6th 2017 Open Pit + Underground
posted on
Mar 06, 2017 10:42AM
Diamond Development & Exploration
Baffin Island, Nunavut ♦ Manitoba ♦ Northwest Territories
VANCOUVER, BRITISH COLUMBIA--(Marketwired - Mar 6, 2017) - Peregrine Diamonds Ltd. (TSX:PGD) ("Peregrine" or "the Company") is pleased to announce that it has completed an internal concept study of a potential open-pit plus underground mining development at its 100% owned CH-6 kimberlite pipe at the Chidliak Diamond Project near Iqaluit, Nunavut, Canada. The study was completed in consultation with JDS Energy & Mining Inc. ("JDS"). The study has concluded there is the potential to substantially enhance the economics of the Chidliak Project by incorporating an underground mining operation below 260 metres of depth at CH-6, the current bottom of the open pit Inferred Resource defined in the August 2016 Preliminary Economic Assessment ("PEA") (see below). As a result of this conceptual study, a drill program targeting this deeper kimberlite is planned to commence in June 2017 to expand the resource to depths up to 500 metres below surface. In addition to the resource expansion drilling, geotechnical work and environmental studies in the Chidliak Project area and proposed transportation corridor will continue.
CH-6 PEA AND OPEN PIT PLUS UNDERGROUND CONCEPT STUDY
JDS completed a positive preliminary economic assessment titled "Preliminary Economic Assessment Technical Report of the Chidliak Project, Nunavut, Canada" dated August 19, 2016 on a Phase-One open-pit only mining operation of the CH-6 and CH-7 kimberlite pipes.
The economics of a development at Chidliak are robust. Highlights of the 2016 Chidliak Phase-One, Open-Pit, Diamond Development PEA base case are:
Pre-tax Net Present Value (NPV) of C$743.7 million, at a 7.5% discount rate and a pre-tax Internal Rate of Return (IRR) of 38.1%.
After-tax NPV of C$471.2 million, at a 7.5% discount rate and an after-tax IRR of 29.8%.
Total Life of Mine (LOM) pre-tax Free Cash Flow of C$1.31 billion.
After-tax payback period of two years, LOM of ten years.
Operating margin of 72%.
LOM average production rate of 1.2 million carats per year, peaking at 1.8 million carats per year.
Estimated pre-production capital requirement of approximately C$434.9 million, including C$56.7 million in contingency.
The PEA is preliminary in nature and includes Inferred Mineral Resources that are considered too speculative geologically to have the economic considerations applied to them to be categorized as Mineral Reserves. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. There is no certainty that the PEA will be realized. All mine plan tonnes in the PEA are Inferred Mineral Resources.
The PEA concluded that the project was of sufficient merit to proceed to the Preliminary Feasibility Study ("PFS") stage. The key components of the recommended work program include:
Core drilling at CH-6 to better quantify the target for further exploration ("TFFE") and possibly convert that material to a Mineral Resource.
Bulk sampling of CH-6 to advance the resource to the Indicated level.
Engineering and geotechnical programs to better quantify process requirements and refine pit design.
Continued environmental monitoring and development of permitting management plans.
In December 2016, the Company engaged JDS to complete an internal, concept-level study on the project economic uplift that could be realized by developing the CH-6 kimberlite to a depth of 500 metres as a combined open-pit plus underground mining operation. The results of this study are excellent and have significantly changed the specifics for the 2017 work program. The study clearly demonstrates the benefit of focusing the 2017 program on proving the resource potential at CH-6 below 260 metres, the current bottom of the Inferred Resource in the PEA.
As a "concept study" does not conform with NI 43-101 requirements, the study, and its technical and economic details, cannot be publicly disclosed
CURRENT CH-6 TFFE
On April 7, 2016, the Company released updated independent estimates of TFFE for the CH-6 kimberlite below 260 metres of depth as shown in Table 1 below.
TABLE 1: CH-6 KIMBERLITE TFFE BELOW 260 METRES
Domain Depth Low-case Tonnes (millions) High-case Tonnes (millions) (metres below surface) CH-6 KIM-L 260-380 1.27 2.40 CH-6 KIM-C 260-380 0.88 1.09 CH-6 TFFE 260-380 2.15 3.49
The KIM-L TFFE was estimated based on 112 metres of core logged as KIM-L in five vertical core holes extending below the 260 metre depth of the KIM-L resource, and on extrapolation to depth of the CH-6 pipe shell, which is well constrained at shallower depths. Vertical core hole CHI-050-11-DD24, drilled in August 2011, intersected KIM-L throughout the length of the hole to its terminal depth of 300 metres, and was sampled for caustic fusion diamond assay over the 266 to 299 metre depth range. Diamond recovery results are presented in Table 2.
TABLE 2: DIAMONDS RECOVERED BY CAUSTIC FUSION FOR CH-6 KIM-L (TFFE) FROM HOLE DD24
Geological Depth Sample Diamond count by sieve size (mm) Total Carats Unit (m) Weight Diamonds (+0.85 (kg) mm) +0.106 +0.150 +0.212 +0.300 +0.425 +0.60 +0.85 +1.18 +1.70 +2.36 +3.35 -0.150 -0.212 -0.300 -0.425 -0.600 -0.85 -1.18 -1.70 -2.36 -3.35 -4.75 CH-06 266 40.2 36 16 10 7 5 3 1 1 0 0 0 79 0.04 (KIM-L TFFE) to 299
The caustic fusion result is consistent with a coarse diamond size distribution within the KIM-L unit and with caustic fusion results for KIM-L from sampling within the current Inferred Resource. This fact, paired with the geological continuity identified within KIM-L throughout CH-6, emphasizes the importance of kimberlite below 260 metres being targeted by the 2017 drilling program.
The TFFE's identified above are conceptual in nature and are not Mineral Resources. It is uncertain whether further exploration will result in any of these tonnages being delineated as Mineral Resources.
2017 CH-6 WORK PROGRAM
The 2017 work program at Chidliak will now focus on three main objectives:
Expansion of the current Inferred Resource at CH-6 - through diamond core drilling of approximately 4,000-5,000 metres to further demonstrate geological continuity, establish pipe margin pierce-points and obtain spatially representative kimberlite samples for caustic fusion diamond assay. The main objective will be to increase the depth of a categorized resource from 260 metres to 500 metres. Caustic fusion results will be used to model diamond grade and grade distribution of the kimberlite to 500 metres.
Refine open pit geotechnical design parameters - as part of the 2017 drilling program, oriented HQ diameter core and other geotechnical data required to refine the open-pit parameters, particularly the pit slope angles, will be acquired. This data will enable assumptions regarding open pit design to be tested and further refined.
Advancing permitting - through continued environmental monitoring programs of the Chidliak Project area and the proposed transportation corridor.
The Company is currently working with Mineral Services Canada to finalize parameters for the 2017 drill program that would support robust future resource estimates. All necessary preparations to initiate this program, including equipment acquisition and camp preparation, were completed in 2016 and all permits have been obtained. The Company expects the microdiamond analyses to be completed in the third quarter of 2017 and anticipates an updated resource for CH-6 to be declared in the fourth quarter. If the resource at depths below 260 metres is of sufficient size and diamond grade, a new PEA outlining an underground mining operation for this material, in addition to the existing open-pit operation, could be completed in the first quarter of 2018. Total cost for the 2017 work program is estimated at C$7.5 million.
FINANCING FOR THE 2017 PROGRAM
The Company is in discussions with various parties regarding financing for the 2017 program and is confident such financing will be obtained. Detailed information will be provided if and when a financing option is selected by the Company.
QUALIFIED PERSONS
Mr. Gord Doerksen of JDS Energy and Mining Inc. is a Professional Engineer and an independent, external Qualified Person that consults to Peregrine. Dr. Tom Nowicki of Mineral Services Canada Inc., is a Professional Geologist and is Peregrine's independent, external Qualified Person for resource estimates. Dr. Herman Grütter, Peregrine's Vice President, Technical Services, is a Qualified Person and is responsible for the design of the Diamond Resource Development Program at Chidliak.
Mr. Doerksen, Dr. Nowicki and Dr. Grütter have reviewed this release and approve of its contents.