PRE-BLAST REPORT
BRICK MECCA QUARRY 6/10/2014
This document entails the works done by Brick Mecca to establish the quarry at farm Taaiboshfontein for the production of Dolerite. The Report will cover aspects such as site establishment/infrastructure, construction, excavations, and machine set up.
SITE ESTABLISHMENT/INFRASTRCUTURE
All site establishments has been done with machinery ranging from Graders, Bull Dozers, Excavators, Dumpers, Front end Loaders and TLB`s . Entrance and Exit Roads have been established and new boundary fencing installed. New gates and walls have been erected to add to the security of the site as well as to the aesthetic appeal. Topsoil has been removed on site and stored on surge piles for later rehabilitation. An 80m bore hole has been sunk for the water supply on the Quarry as well as for the livestock of the farmer, a 500m class 12 water pipeline has been installed to the Quarry from the borehole with pressure reducing valves to the farmers existing class 3 pipeline. A septic tank system has been installed for the office and outbuilding sewerage. All site establishment procedures have been done in such a way as to incur as little damage/intrusion to local Fauna and Flora. Trees, flowers and lawns have been planted to reduce dust and to encourage natural plant growth.
CONSTRUCTION
Construction of various aspects has been done on the Quarry for site establishment and machine setup. A site Office has been constructed with an office for the manager and an office for the onsite admin personnel that will run the weighbridge. A 24m weighbridge has been constructed to insure correct and accurate loads for the brick plant and for costumers. A large store room has been constructed with three different compartments, a power plant compartment with a 325Kva generator and a 200Kva generator to run the plant until Eskom Transformer has been installed. An enclosed store room for the safe lockup of spares and tools, and a open workshop for maintenance purposes. A large 5.4m high bulkhead has been constructed for the 18x32 Telsmith jaw unit to ensure safe tipping of dumper trucks. A 6m reinforced container has been placed below in situ to serve as a feeding chamber for the surge pile form the 18x32 jaw unit. Various areas have been concreted and paved to ensure correct levels bases for machines. Construction of conveyors took place on site as well as all machine assembly`s and commissions.
EXCAVATIONS
Excavations on site have been done for all building work foundations and bases for machines. All topsoil and overburden on Quarry has been excavated where necessary and stockpiled for rehabilitation. A new sump/dam has been excavated to retain ground and surface water from within the quarry. All haul roads have been backfilled with excavation materials, compacted and graded. 15 000 tons of overburden has been excavated from the top of the Bench to enable drilling. 20 000 tons of topsoil, clay, vegetation, boulders and filling material has been excavated out of the quarry pit to ensure no cross contamination of the blasted dolerite.
MACHINE SET UP
The mine`s machine set up is based on the main objective of the mine and that is to produce a -5mm (Crusher Dust) produce for Brick Mecca to enable Brick Mecca to produce bricks of the highest standard. The machines as in production lines are as follows.
Concrete Stone and Dust Plant
• 18 x 32 Telsmith-Osborn Jaw unit with 14 cube hopper with vibrating grizzly feeder.
• 1608 Hiberia, Horizontal Impact Crusher from Metallum.
• 4x12 double deck screen
• 4x12 triple deck screen
• 5x14 triple deck screen
Road Stone Plant
• T7 Techroq Vertical Shaft Impact Crusher
Filling Plant
• 10 x 36 Telsmith-Pegson Jaw unit.
POST BLAST REPORT
Blasting
The Blasting and Drilling was done by SureBlast and was a massive success. 155 holes with a 100mm diameter were drilled vertically into the cleared out Bench. On the day of blasting the detonators were inserted into the boosters and lowered into the blast holes, emulsion explosives was then pumped into the blast holes leaving a 1.8m gap at the top for the 13mm crushed stone to be poured in as stemming. The stemming keeps the energy of the explosives contained for a fraction of a second to insure that the explosives can work efficiently. The 12 000 cube blast produced in the order of 33 600 tons of Dolerite at an average ratio of 2.8tons per cube. A powder factor of 1.2 was used and the majority of the bench was reduced to a -300mm product. A very small percentage oversize boulders were produced that would not be able to pass through the 18x32 jaw unit. These boulders will be used as safety berms on roadways and benches. A few cracks can be seen on the excising bench behind the blast due to over break. These cracks will be opened from the top of the bench by a 45 ton excavator and the lose boulders will be pushed of the bench to insure the safety of personnel and machinery working below.
