Since 2010, Dumas has been involved in the construction of the Jacob Timmers Shaft in the District of Huayllay, Province of Cerro de Pasco, Peru. This is a 585 metre deep concrete lined shaft with a finished diameter of 4.4 metres.
The Jacob Timmers Shaft project is particularly challenging due to a shaft collar elevation of 4,636 metres AMSL. There remains approximately 15 metres of shaft sinking until completion, followed by loading pocket excavation and construction. The project went over two years without a lost time injury.