Edna May Project

Scope of Work

GR Engineering was appointed by Catalpa Resources Limited to undertake the engineering, design, procurement, construction and commissioning of the Edna May gold processing plant. Catalpa had previously procured the old Big Bell processing plant, equipment and infrastructure to meet most of the processing requirements.  Additional equipment was required to meet the new duty of the upgraded processing plant. Part of the GR Engineering scope was to manage the refurbishment of the Big Bell plant and incorporate the new equipment into the Edna May plant design.

The plant is designed to treat blended ore, at a throughput of 2.8 Mtpa.  The grinding and wet plant circuits are designed to process ore at a treatment rate of 3.4 Mtpa. The plant has provision for a full expansion in processing capacity to 3.2 Mtpa.

Blended ore is processed through a conventional single stage jaw crushing circuit. Crushed ore is stored on a coarse ore stockpile with a live capacity of approximately 3,800 tonnes. The grinding circuit consists of a primary SAG mill, a secondary ball mill and pebble crushing circuit. Gold recovery consists of both a gravity circuit and intensive cyanidation units incorporating a hybrid CIP/CIL circuit, consisting of 2 leach and 6 adsorption vessels. Loaded carbon is stripped of gold using a Zadra pressure type elution circuit with gold subsequently recovered from the cathodes of the gravity and elution electrowinning cells. 

GR Engineering commenced the EPC design, construction and refurbishment of the process plant facilities in May 2009 and the project was completed in May 2010.

Capacity Upgrade

Subsequent to the completion of the Edna May gold processing plant, GR Engineering has undertaken a capacity upgrade facilitated by the supply, installation and commissioning of a second hand, 24m diameter tailings thickener to assist with water recovery, design and installation of a fuel farm and the design and implementation of various plant improvement and debottlenecking projects.


Project Fact Sheet

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Associated News

Edna May project awarded to GRES

Edna May project awarded to GRES

GR Engineering Services have received a "Letter of Conditional Award" from Catalpa Resources Limited enabling GRES to commence project works for the Edna May Operations.

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  • Client Evolution Mining Limited (ASX: EVN) (formerly Catalpa Resources Ltd)
  • Location The project is located 1.0 km north of Westonia (312 km east of Perth) in Western Australia.
  • Award Date May 2009
  • Completion Date May 2010
  • Project Type Greenfields, EPC design and construct 
  • Project Manager Andrew Bennett
  • Process Manager Gerard Neeling