This specification supplements the requirements of the Occupational Health and Safety Act, and its Regulations.

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1 SPEC /9 1.0 PURPOSE This specification describes the minimum requirements for general grading, excavation of earth, rock and solid slag, embankment construction, ditching, use of explosives, and the disposal of surplus and unsuitable material. This specification supplements the requirements of the Occupational Health and Safety Act, and its Regulations. 2.0 DEFINITIONS "Ditching" means the excavation in earth or in rock for all water courses. The term includes roadside ditches, all excavation lying beyond the end of drainage structures, stream and watercourse diversions and corrections. "Earth Excavation" means removal of quicksand, sand, crushed slag, clay, loam, earth, hard-pan, boulder-clay, old macadam, bituminous or gravel roadway surface, together with removal of old timber, stone filled or stone abutments and piers, boulders and chunks of old concrete and stone masonry up to a size which can be moved and manipulated by conventional earth moving equipment, and every other class of material except those listed in subsequent definitions. Engineer means the Professional Engineer licensed in the jurisdiction in which the work is to be performed. Excavation Permit The excavation permit is a request and authorization form that is used to indicate the absence or presence of buried utilities or other hazards in the area i.e. call before you dig. Excavation permit is required prior to starting any excavation work. "Hoe-Ram Rock Breaking" means breaking of rock by either a pneumatic or hydraulic powered breaker point mounted on a machine operated movable boom. "Overbreak" means the portion of any rock or broken rock that is excavated, displaced or loosened outside and beyond the designated excavation limit(s), regardless of whether it has been excavated, displaced or loosened due to the inherent character of the rock formation or due to any other cause. "Rock Excavation" means removal of solid rock in place, or boulders and chunks of old concrete and stone masonry sized not less than one cubic yard which require drilling and blasting to allow removal by conventional earth moving equipment. "Shatter" means the "in situ" fracturing of rock by the use of explosives. "Solid Slag Excavation" means removal of poured furnace slag found in its undisturbed state.

2 SPEC /9 "Sound" or "suitable" as applied to subgrade materials means undisturbed, compact and having the required bearing capacity, stability and other required characteristics. "Unstable" or "unsuitable" as applied to subgrade materials means in a loose state, or too wet, frozen, or containing ice, snow, organic or other deleterious matter, or having poor characteristics for grading and compaction, or having other characteristics which may result in undesirable settlement or movement of foundations, fills or other superimposed loads, or otherwise not meeting the requirements of the specifications. However, this definition permits compacting, drying, dewatering, thawing and any other remedial work, improvements or processing where same is required by or permitted by the specifications and the Vale Representative..0 GENERAL REQUIREMENTS.1 SUBMITTALS Submit all design and calculations, methodologies, construction drawings and plans for cofferdams, cribs, shoring, sheathing, bracing, rock and slag excavation prepared by the contractors engineer to the Vale Representative for review at least (2) weeks prior to performing the work. This review by Vale does not absolve the contractor or their engineer of any liability in regards to the documents submitted. Submit the name of the engineer the design and calculation to Vale representative prior to commencing work..2 SLOPE STABILITY The Stability of the excavation slopes and stockpiling slopes of the excavated materials where the depth is in excess of 4 feet (1.22 meter) must possess their own technical report or plans produced by a qualified professional, including the following items: Physical characteristics of the mound/slope; Total height; Elevations of base and crest; Overall slope angle; Height of earth banks; Width of periodic horizontal strips; Height of slopes between periodic horizontal strips; Slope angles between periodic horizontal strips; Operational lifespan; Area occupied; Degree of risk; Vegetation or synthetic protection measures on earth slopes exposed to the weather; Possible obstructions to the operation of machinery/equipment that may be positioned in areas close to

3 SPEC-1100 /9 slopes or other earthworks, in terms of the dynamic effects that their operation may have on the mounds; Earth banks used as access routes must meet traffic safety criteria.. TEMPORARY DEWATERING AND SEDIMENT CONTROL Provide equipment and facilities and perform work to make and keep the work areas dry of both surface and sub-surface water and when requested by the Vale Representative to remove sediments from water before it leaves the site. Dewater continuously through all work stoppages including overnight, weekends and holidays to protect work in progress. Remove the temporary facilities when they are no longer necessary and restore the areas disturbed by dewatering and temporary sediment control. Contractor is to design, supply, install and maintain dewatering and sediments control systems. The design shall be prepared by a qualified engineer registered in the jurisdiction in which the work is to be performed..4 COFFERDAMS AND CRIBS Extend cofferdams and cribs for foundation excavations well below bottom of Footings as required for stability and water-tightness. Brace and maintain as water-tight as possible. Allow adequate interior dimensions of cofferdams to permit clearance for construction of forms and inspection of their interiors, and to permit pumping outside formwork. Ensure cofferdams or cribs that are tilted or move laterally during process of sinking are righted or enlarged so as to provide necessary clearances. Contractor is to design, supply, install and maintain the cofferdams and cribs. The design shall be prepared by a qualified engineer registered in the jurisdiction in which the work is to be performed..5 SHORING AND BRACING Do not excavate below existing structural or equipment foundations until any required underpinning and shoring has been installed and reviewed by the Vale Representative. Design, supply, place and maintain sheathing, bracing and shoring as applicable to support sides of excavation. Do not disturb installed work, existing structures, utilities and surface features by the arrangement of sheeting, bracing and shoring and its removal. Prevent voids outside sheeting. Promptly fill and compact voids that occur.

4 SPEC /9 Contractor is to design, supply, install and maintain the shoring and bracing. The design shall be prepared by a qualified engineer registered in the jurisdiction in which the work is to be performed..6 BLASTING OPERATIONS Ensure the method conforms to all applicable laws and regulations and to proven safe practices for the type of rock, proximity to structures and other installations, and other conditions. Prevent opening of seams or otherwise disturbing or breaking the rock beyond the required lines, levels and grades. Use line drilling and pre-splitting, or some other approved method, where concrete is to be placed directly against rock and elsewhere as necessary. Use approved blasting mats to restrain movement of material. Provide flagman, signs, sirens and other means necessary for safe use of explosives. Give all notices required by applicable regulations and safety requirements in addition to notices required by the Vale Representative. Before each blast, clear all personnel, vehicles, etc., from the blast area to safe limits and then ensure no personnel, vehicles, etc. enter the area until after completion of the blast. Scale the sides of rock cuts as soon as possible, preferably as the sides become exposed. Advise the Vale Representative 24 hours in advance of blasting. Do no blasting at plant or mine entrances within 0 minutes of Vale shift change times. Complete blasting that is required within 50 feet of any intended new construction prior to commencement of that construction. Contractor is to design, and controls the blasting operations. The design shall be prepared by a qualified engineer registered in the jurisdiction in which the work is to be performed..7 ROCK SPLITTING OPERATION Breaking or splitting operations do not require the clearing of the area of personnel or equipment while breaking operations take place providing the splitting takes place without shocks, vibrations, or flying objects. Contractor is to Design, and controls the rock splitting operation. The design shall be prepared by a qualified engineer registered in the jurisdiction in which the work is to be performed..8 HOE-RAM ROCK BREAKING OPERATIONS Hoe-ram rock breaking does not require the clearing of the area of personnel or equipment while the operation takes place providing care is exercised to ensure that flying rock does not leave the excavation area.

5 SPEC /9.9 EXCAVATED MATERIALS Stockpile excavated materials within designated areas as identified in the contract documents and by the Vale Representative. Haul excess material, not required for other purposes, to a location designated in the contract documents and dispose of as directed..10 WITHIN ROADWAYS The Vale Representative will arrange permission for excavations in roadways from appropriate authorities. Abide by the regulations imposed by that authority during excavation. When it is necessary to cut existing asphalt pavement, curbs, and the like, cleanly cut using approved power tools designed for such purposes before commencing excavation. Do not use equipment that will damage pavement beyond limit of excavation..11 ENVIRONMENTAL REQUIREMENTS Provide hoarding, heating, drying and all other actions necessary to produce satisfactory conditions to ensure continuation of work during rain, snow, freezing weather or other unsatisfactory conditions, if such continuation of work is necessary to suit the contract schedule. The design shall be prepared by a qualified engineer registered in the jurisdiction in which the work is to be performed..12 REMOVAL TOLERANCE Excavate to the required lines, level and grades. Do not excavate or disturb beyond the required lines, levels and grades unless otherwise requested by the Vale Representative. Where the required lines, levels and grades are not otherwise defined, excavate as necessary for the items that are to be placed in the excavations and as necessary to provide working space to install and inspect those items. In such cases, excavate to safe side slopes or sheet, brace and shore the sides of the excavations but keep trench sides vertical below 12 inches above the top of any pipe or duct to be placed in the trench. Protect the excavations and prevent disturbance of the sides of the excavations by traffic or other superimposed loads near the excavations.

6 SPEC / GENERAL Prior to proceeding with any excavation work, the contractor shall fill out and complete the excavation permit to ensure all buried services have been located. It is the contractor s responsibility to ensure that buried services have been located prior to commencing with excavation. Unless stated otherwise, assume that material to be excavated is earth. Inform the Vale Representative when the excavations reach the depths required by the lines, levels and grades. If the undisturbed naturally occurring material at those lines, levels and grades is unsuitable then, when so ordered by the Vale Representative, remove the unsuitable material and replace it with suitable fill. Remove all disturbed material and all material which has become unsuitable due to inadequate protection, inadequate dewatering or any other reason and replace with suitable fill. The Vale Representative may vary the design to minimize the additional costs where the Vale Representative orders removal of undisturbed naturally occurring unsuitable material beyond the required lines, levels and grades. Where fill is to be placed on existing slopes, bench the existing slopes where necessary to the approval of the Vale Representative. Dispose of unsuitable materials and surplus excavated materials in the designated disposal areas only. Rough grade those materials in the disposal areas to promote drainage and to give a tidy appearance to the satisfaction of the Vale Representative. Prevent injury and damage during all work. 4.2 SUITABLE FILLS All suitable fills to be in accordance with the contract documents. Unless noted otherwise on the contract documents use: 15 MPa concrete under: - Structural foundations - Equipment foundations In other areas where fill is required and not specified on the contract documents, call Vale representative and the engineer to specify the fill required.

7 SPEC /9 4. SOLID SLAG Where solid slag is excavated, excavate sufficient overburden to allow proper cross-sectioning of excavation. Grade and clear bottom of excavations of all loose slag. If excavations are made to a depth greater than shown on the drawings or authorized, backfill to the correct lines and grades by a method approved by the Vale Representative. Contractor is to design and develop proper methods for excavating solid slag. The design shall be prepared by a qualified engineer registered in the jurisdiction in which the work is to be performed. 4.4 ROCK Without limiting the other precautions to be taken, take the following precautions when dewatering, blasting, excavating (rock or other material), vibrating or using heavy equipment near existing buildings, roads or other existing installations. Before commencing any activities that might affect existing buildings and other installations, the contractor and the Vale Representative shall inspect those buildings and other installations. Apply "tell-tale" tapes across existing cracks, photograph existing cracks, existing signs of settlement and other visible defects. Measure and record the elevations and locations of enough points on the buildings and other installations to allow adequate monitoring to detect any movement of the buildings and other installations. Record all observations of existing conditions. Where footings bear on rock, bench rock so that slope of rock does not exceed 2 vertical in 12 horizontal. Inspect the buildings and other installations after each blast. Re-measure the points sufficiently frequently to detect movement or damage at the earliest possible time. Change the methods or stop the dewatering, blasting, excavating, or other activities immediately if movement or damage is detected. Provide seismic equipment with a qualified operator and take adequate measurements to determine the effect of each blast. Vary the charges, detonation delays, blast pattern and other factors when the seismic test results indicate variations are necessary. Provide equipment to monitor noise levels where there are limits on allowable noise levels. Promptly provide to the Vale Representative a copy of all records of the above inspections and measurements and records of existing conditions before commencing work.

8 SPEC /9 5.0 REFERENCE DOCUMENTATION The following documents are related to this specification and shall be used to their latest revision: RSO 1990, c O.1, Regulation O.Reg.21/91 Occupational Health and Safety Act Construction Projects

9 SPEC /9 6.0 REVISION AND TRANSITION NOTES Revision notes describe: what was changed, and if applicable, why it was changed, and the plan to implement the change, including whether changes are retroactive. Note: The revision notes are a summary of the changes and may not necessarily be a complete list. Rev 1 Description Document format and number changed due to Vale Engineering Document Program changes in Previous Standard number was Rev 6 Revision by Approved by Issue Date YYYY/MM/DD K.Clausen A.Alaeddine 2012/04/0 2 Approved for use in Thompson, MB - No changes. K.Clausen A.Alaeddine 2012/08/09 Document Reviewed Format updated Regional approvals removed K.Clausen A.Alaeddine