|($ millions)||Previous Guidancea||Revisions||Revised Guidance|
|Los Diques Tailings||120||15||135|
|Total Sustaining Capital||350||75||425|
|Zinc Expansion (Neves-Corvo)||-||30||30|
|Zinkgruvan Expansion (1350)||5||-||5|
|Total Expansionary Capital||40||25||65|
|Total Capital Expenditures||390||100||490|
|a. Guidance as outlined in our Management's Discussion and Analysis for the three months ended March 31, 2017.|
Fourteen rigs drilled 41,464 metres within the three existing underground mines, around the Candelaria open pit mine and on surface in the south district to rapidly expand Mineral Resource and Mineral Reserve estimates and to determine the potential extension of known ore bodies. Geophysics continued in the south district in the second quarter to assist in the development of drilling targets for the remainder of the year.
Eagle exploration continued in 2017 with four surface rigs. Drilling is focused on tracing the Eagle East conduit. A total of 10,368 surface metres were drilled in the second quarter of 2017, with drilling expected to continue into the third quarter. In addition, a geophysical program is in preparation for the 2017 field season.
Exploration planning sessions were held at both Zinkgruvan and Neves-Corvo aimed at strategically expanding exploration efforts for both zinc and copper mineralization extensions. A significant ramp up in exploration activity is underway and will continue for the balance of the year and throughout 2018.
Field work commenced on a copper/gold exploration project acquired in late 2016. Initial work includes geophysical surveys, geological mapping and surface rock and soil sampling, which is aimed at outlining potential drill targets.
Project evaluation work is continuing on new copper and zinc-lead opportunities in Eastern Europe. Prospecting permits for polymetallic mineralization were obtained in Romania in an area with a long history of copper-gold mining activities. It is expected that field work will commence on several projects early in the third quarter.