Power for the existing projects in the Maricunga region is normally sourced from near Copiapó and carried to the mines by private power lines owned by the operating companies.
Exeter has a detailed and focused water exploration strategy to meet the water requirements of the various project scenarios. The company has completed a series of exploration programs on various water tenements.
The aggregate flow rate from the six large diameter exploration wells completed at Exeter’s Peñas Blancas1 water concession is now over 400 litres per second (“L/s”), considerably above Exeter’s original target of +200 L/s. The ultimate, cumulative flow rate potential of the aquifer remains open.
Drilling results suggest Peñas Blancas is part of a previously undiscovered, extensive, subterranean aquifer. It is located centrally within a high-altitude basin, where there are no other existing underground water rights. The extensive winter snowfall in the area is believed to be the source of recharge. The Company believes the aquifer could support any of the three identified low capex, development options for the Caspiche project as outlined in the Amended NI 43-101 Technical Report on the Caspiche Project (“2014 PEA”)2. Importantly, the aquifer could also provide an appropriate long term water resource for other potential users in this arid, largely unpopulated region of Chile. Current expectations, based on the 2014 PEA, is that the 30,000 tonnes per day (“tpd”) standalone oxide operation requires peak water requirements of 44 L/s; Option 2, 60,000 tpd open pit and 27,000 tpd gold copper sulphide pit expansion requires peak water of 185 L/s; and Option 3, 60,000 tpd open pit and 27,000 tpd underground gold copper operation requires peak water consumption of 151 L/s. Under all of these new, potentially viable mine plans, water requirements are significantly reduced. Exeter’s current water activities are targeting to secure sufficient water to meet the requirements outlined within the 2014 PEA studies.
The objective of Exeter’s water program is to identify, evaluate, and secure water sources to support a potential initial heap leach gold stage and a follow-on gold-copper sulphide stage of mining at Caspiche. Preliminary, internal studies relating to developing Caspiche as a smaller scale, staged mine indicate potential for a significantly lower water requirement.
In January 2017, Exeter signed an option agreement with Cleanairtech Sudamerica SA (“CAT”) to supply 50 litres per second (L/s) of desalinated water. It is the Company’s intention to use this water in construction, commissioning and operation of the first stage heap leach gold facility at Caspiche, subject to the outcome of a feasibility study.
1 Exeter’s Chilean subsidiary, Minera Eton (“Eton”) and the Chilean subsidiary of Canadian company Atacama Pacific Gold Corporation are jointly exploring (“JV”) for water in Northern Chile where Eton is earning an aggregate 90% interest in the Peñas Blancas concession and other water concessions. See Exeter news release NR 14-02 dated February 27th, 2014.
2 Amended NI 43-101 Technical Report on the Caspiche Project (“2014 PEA”). See the Exeter web site or Sedar for the details regarding the 2014 PEA.