The Navan Orebody is a world-class carbonate-hosted Zn-Pb deposit comprising complex tabular lenses within Lower Carboniferous limestones and excluding depletion, would be over 130Mt in size. Detailed descriptions of the geology are available in a number of publications of which Ashton et al., (2015) is the most recent. The discovery of the Tara Deep satellite and outline geology are summarized in Ashton et al., (2018). Central Ireland comprises generally flat lying sequences of Lower Carboniferous limestones with common inliers of sedimentary Lower Palaeozic and Devonian rocks. The limestones are cut by numerous, locally syn-depositional NW to ENE trending major normal faults and these control the location of several carbonate hosted Zn-Pb deposits, of which Navan is by far the largest. In eastern Ireland, the Carboniferous Limestones are part of the Dublin Basin, a significant feature that after extensional basin-margin faulting and later Hercynian inversion, exposes some large Lower Paleozoic inliers at its margins and exhibits some outliers of Namurian and later Permo-Triassic sediments. The Navan Orebody is located on the footwall (northern) side of a major south-dipping normal fault that constitutes a basin margin controlling feature. The orebody itself is controlled by a complex array of Lower Carboniferous normal faulting and slides on the uplifted footwall of this major fault. The orebody generally dips at about 10-15 degrees to the WSW and comprises several, loca ........

Boliden Tara Mines is an underground zinc and lead mine producing 2.6 million tonnes per year with an annual development schedule of 13km and nearly 250km of active tunnels it is classed as the biggest zinc mine in Europe and one of the largest in global comparison. Tara Mine uses Drift and Slash and Long Hole Stoping as its main mining methods and has a current depth of around 1km. In most areas of the mine open-stopes are designed parallel to the strike direction of the orebody such that in-stope development is sub-horizontal, whereas in the upper-near surface sections the open stopes are along dip and may necessitate slightly more complex development. In both cases, ore thicknesses up to about 20m can be mined via a single footwall drift with blast-hole drilling drilled upwards. Thicker ore necessitates hanging-wall drifts. In both cases, development is advanced to the end of the stope, and a slot crosscut created from where a raise is blasted using longhole techniques to the orebody hanging wall. Subsequent longhole blasting opens up a slot over full stope width and subsequent long-hole blasting creates a blasted ore muck pile in the developing stope which is mostly mucked-out using remote control and increasingly tele-remote operations. Areas of weak ground, often related to faulting may occur in the back and/or sidewalls of stopes. These are secured using various cable bolts patterns. Once a stope is complete, it is backfilled with hydraulically placed cemented sandfra ........

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