Mandalay Resources has stated that it is continuing search operations for two miners who went missing following flooding at the Cerro Bayo operation in Chile earlier this month.  

Underground and surface operations at the site have been suspended since the flood struck at Delia NW mine at the Cerro Bayo operation on 9 June.  

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The Delia NW vein is located approximately 100m landward from the original shore of Laguna Verde. The subsidence of the original shore created a new bay of the lake that measures approximately 100m by 100m. 

The current search operation includes pumping from the flooded ramp and exit, as well as drilling multiple holes to the bottom level of the mine, around 200m below the surface.  

Two of these holes intersected the target mine workings, but found them to contain water and mud and no trapped air.

According to the company, two more holes currently being drilled are expected to intersect the closest rescue chamber to where the miners were working.

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"The current search operation includes pumping from the flooded ramp and exit."

The company said that that these chambers are designed to protect against contaminated air, and not the significant amount of water pressure present in the area.  

Alongside military expert divers and underwater drones, others assisting the Mandalay rescue operations include Chilean government agencies, local mining companies, drilling companies, and contractors. 

It is claimed that limited visibility in the muddy water has hindered the task of obtaining useful information from the site.

Around 12,000t of ore remained on the bottom of the level, with 12 days of mill throughput at the current rate of 1,000t a day. 

Near-term impact is expected to be minimal on reserves and ultimate total production at the property.

Mandalay confirmed that the reopening of the mine rests on the outcome of investigations.  

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