Carnon Valley Treatment Study and Development Campaign

The core objective of the Works is to provide the data necessary to identify the most cost effective method of treating Wheal Jane and / or County Adit mine waters.

For the various options to be compared objectively, processes must be considered at optimised or near-optimised conditions.

"Optimal" can be a subjective measure, therefore for clarity, the Authority considers "optimised" to mean that the sum of the following costs is minimised for a given set of feed conditions and process type: • Power consumption variable costs • Chemical reagent costs (incl. transport, etc..) • Consumable costs (i.e. replacement electrodes, wear parts, etc..) • Labour costs Other costs and factors will be considered as Sensitivities during the Authority's cost effectiveness appraisals and are not to be included in determining Optimal conditions.

Specifically to be excluded include: • Waste disposal costs • Prospective sale of waste streams • Renewable power use • Sustainability criteria The expectations from a vendor wishing to bid for the treatment study and development campaign are the following: - Technical presentation on the vendor's treatment technology, including the applicability of it to multi-stage metals removal if relevant. - Detailed Proposal, indicating testing plan, total works and scope. - Quotation, itemised by project phase. - Schedule of works.

Case studies and examples of the use of the vendor's treatment technology on mine water, or an equivalent environment.