City of Toronto-St. Clair Reservoir Waterproofing and Building Envelope Rehabilitation 15ECS-MI-01WA / TCN Page 1 of 13

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1 15ECS-MI-01WA / TCN Page 1 of 13 1 General 1.1 DESCRIPTION.1 This section refers to concrete repair work inside or outside of existing tanks and other area related to concrete repair including repairs on horizontal, vertical and underside surfaces..2 In the repair areas which are classified as CONFINED SPACES, the contractor shall include all necessary equipment and resources to perform the repairs in accordance with all applicable regulations, standards and codes..3 All conditions of the Contract and Division 1, General Requirements apply to this section..4 Execute work by fully trained applicators in strict accordance with the printed directions of the manufacturer of the material to be used..5 All materials specified in this Specification should be NSF 61 certificated. 1.2 REFERENCE STANDARDS.1 By-Laws: Conform to the requirements of the Ontario Building Code (latest edition) and all amendments and all local, Municipal and Provincial building by-laws and ordinances..2 Standard Specifications: Except where modified by this section or the Contract Drawings, the specifications listed below shall govern: Standard No. Title CSA-A23.1 Concrete Materials and Methods of Construction CSA-A23.2 Methods of Test for Concrete CAN3-A5 Portland Cement CSA-W186 Welding of Reinforcing Bars in Reinforced Concrete Construction 1.3 SCHEDULE.1 Coordinate work under this section with work of related sections..2 Include an allowance in schedule for Engineer to inspect and document as per Section 3.1. Note that sequence of work will determine when specific areas are available for cleaning and inspection. Each specific area will require a separate allowance as outlined in Section The Contractor shall include all resources and time required to complete all repairs as shown on the Contract Drawings in the total contract lump sum price. Scaffolding should be included for all types of repairs other than repairs on the floor.

2 15ECS-MI-01WA / TCN Page 2 of DEFINITIONS.1 Horizontal ALL horizontal surfaces within +/- 15 degrees of the horizontal plane. This applies to the topside of the horizontal surface only..2 Vertical ALL vertical surfaces within +/- 15 degrees of the vertical plane..3 Underside ALL other surfaces..4 Condition Survey Report A report prepared by the Engineer to document the repairs required; the repair types, the repair areas, and the repair lengths/areas/volumes. 1.5 SUBMITTALS.1 Product Data: Include material descriptions, chemical composition, physical properties, test data, and mixing and applications..1 Include Material Safety Data Sheets, if applicable..2 Qualification Data:.1 Installer shall have a minimum 5 years proven experience for the similar concrete repair projects..2 For installers, to demonstrate their capabilities and experience, include lists of completed projects with project names and addresses, names and addresses of Engineers and owners, and other information specified..3 For products required to be installed by workers approved by product manufactures, include letters of acceptance by product manufactures certifying that installers are approved to apply their products..3 Material Test Report: From a qualified testing agency indicating and interpreting test results for compliance of bonding agents, patching mortars with requirements indicated..4 Repair program for each phase of the repair process, including protection of surrounding materials and project site during operations. Describe in detail the materials, methods, equipment, and sequence of operations to be used for each phase of the Work..1 If alternative materials and methods to those indicated are proposed for any phase of repair work, submit substitution request complying with Division 1 and provide a written description of proposed materials and methods, including evidence of successful use on other comparable projects, and a testing program to demonstrate their effectiveness for this project.

3 15ECS-MI-01WA / TCN Page 3 of REPAIR METHODOLOGY.1 The Contractor shall be responsible for mobilization/demobilization, equipment, materials, testing, labour and other items and services required to accomplish the work..2 Equipment and techniques proposed for use in the work shall not be used until they have been demonstrated and approved by the Engineer. 1.7 PROTECTION.1 Protect surrounding areas and surfaces from damage during work of this section..2 Prevent precipitation and debris from entering openings during work..3 Protect process piping and equipment from damage, dust and debris with tarps or plastic sheeting. 1.8 DELIVERY AND STORAGE.1 Deliver and store all repair materials in accordance with manufacturer's instructions..2 Store materials under cover on elevated platforms, stored in weather-tight buildings, bins, or silos, which will exclude moisture and contaminants..3 Cement shall be furnished in suitable bags used for packaging cements. Labelling of packages shall clearly define contents, manufacturer, batch identification, etc. Reinforcing bars and accessories shall be stored in such a manner as to avoid contamination and deterioration..4 Protect materials from freezing. Materials suspected of having been subjected to freezing are not to be used unless the Manufacturer verifies in writing the material has not been damaged..5 Deliver and store materials in original packages with labels intact..6 Remove and replace damaged, wet or broken materials..7 Store materials away from open flame or ignition sources. 1.9 WARRANTY.1 Submit a written warranty for concrete repairs specified in this section covering a period of two (2) years unless otherwise noted, including materials and application, at no cost to the Owner.

4 15ECS-MI-01WA / TCN Page 4 of 13.2 Defective concrete repairs covered under the warranty shall include but not be limited to, debonding of patches from substrate, and cracking. Replacement and repair of defective concrete repairs shall be in accordance with this section SITE REVIEW AND TESTING.1 Concrete repairs will be inspected and tested on behalf of the Owner by the Engineer or his/her Site Representative. The Contractor is required to co-operate with, and provide access and samples to the Engineer. Concrete will be tested in accordance with CSA-A23.2 to determine its compliance with the specification..2 The bond between the existing and new grout will be evaluated in accordance with grout manufacturer s instructions..3 Any work not accepted by the Engineer shall be immediately corrected by the Contractor to the Engineers satisfaction..4 Cylinder testing may be required (repair type and size dependent). The Engineer will arrange testing at the owner s expense EQUIPMENT.1 Cleaning.1 Equipment used in cleaning shall not cause staining, erosion, marring, or other damage or changes in the appearance of the surfaces to be cleaned..2 Sandblasting.1 Sandblasting equipment shall not be used in cleaning concrete and other building surfaces; and shall be subject to approval for each other specific applications..2 Sandblasting equipment shall be permitted for use in cleaning of reinforcement and other embedded metal items for sandblasting to SSPC-SP10 near white blast finish. The compressor shall be equipped with traps that will maintain the compressed air free of oil and water. The nozzle shall have an adjustable guide that will hold the nozzle aligned with the reinforcement and other items to be cleaned, and will maintain the nozzle approximately 25 mm (1 inch) above the surface. The height, angle of inclination and the size of the nozzle shall be adjusted as necessary to provide satisfactory results. The Contractor shall provide protective covers and barriers as required to control dust and prevent over-spray onto adjacent surfaces..3 Water Blasting.1 Water blasting equipment shall include a trailer-mounted water tank, pumps, high-pressure hose, wand with safety release cut-off control, nozzle, and auxiliary water re-supply equipment. The equipment shall not be operated at a pressure, which will cause etching or other damage to the concrete surface.4 Concrete Removal (Excavation)

5 15ECS-MI-01WA / TCN Page 5 of 13.1 The equipment used to excavate concrete shall be handheld manual or power type with a low-impact energy output and shall have gad points. The use of chisel points is prohibited. Surface grinders for use in preparing concrete and metal surfaces shall be small, hand-held equipment with a slow to moderate operating RPM, using stone grinding wheels. Saw cutting equipment shall use circular diamond blades. The blade shall be at least 3.2 mm 1/8 inch thick, with blade diameter selected as appropriate for the application. Excavation equipment shall be subject to approval..5 Drilling.1 Equipment used to drill holes in concrete for patch anchors and other applications shall be standard handheld masonry drills, commonly used for drilling small holes in concrete and masonry. The drill shall be a small, powered, handheld type, using rotary drilling mode only. Impact and rotary impact type drills are prohibited..6 Finishing and Texturing.1 Hand tools used for placing, finishing and texturing concrete and mortar shall be commercially available and commonly used in concrete construction and repair. Equipment used for finishing and texturing concrete and mortar surfaces shall be a type commonly used in the concrete construction and repair industry for that application. Surface grinders, impact tools, and other equipment shall conform to the requirements specified herein, except as specifically required by the type of finish and texture, and subject to approval..7 Compressed Air Supplies.1 Compressed air shall provide clean, oil and moisture free compressed air at the surface to be cleaned. The compressed air line shall have at least two in-line air filters to remove oil and moisture from the air supply. The compressed air supply shall be tested during each shift for the presence of oil and moisture..8 Mixing, Transporting, and Placing.1 Equipment used for mixing, transporting, placing, and confining concrete and mortar placements shall be suitable for the intended purpose and be capable of satisfactorily mixing material, and supporting placement operations in an uninterrupted manner. Equipment shall be maintained in a clean, good operable condition at all times. Equipment used in the work shall be subject to approval. Defects, and deficiencies in operation or capacity shall be resolved prior to use in the work. Equipment used for batching, mixing, conveying, and placing of materials shall be clean, free of old materials and contaminants, and shall conform to the material manufacturer's recommendations.

6 15ECS-MI-01WA / TCN Page 6 of 13 2 Products 2.1 GENERAL AGENTS, EPOXY ANCHOR ADHESIVES, CEMENTITIOUS BONDING AGENTS.1 Water.1 Water used in cleaning concrete surfaces, used in producing concrete and mortars, and used for curing concrete shall be potable..2 Cleaning Solution.1 The cleaning solution shall consist of a 1:1 to 1:1.5 (water: liquid chlorine bleach) mixture of clean potable water and liquid chlorine bleach. Rinse water shall be clean potable water..2 Or approved alternate..3 Form Release Agents.1 Form-release agents shall be NSF 61 certified, the manufacturer's standard, nonstaining, nonpetroleum based, compatible with surface finish and subsequent surface treatments..2 Or approved alternate..4 Anchor Adhesives.1 HIT-HY 200, NSF 61 certified adhesive for steel dowels and anchor rods/bolts, Hilti Products Inc., unless otherwise shown on the Contract Drawings..5 Epoxy Modified, Cementitious Bonding and Anti-corrosion Agent:.1 Sika Corporation: Sikadur 32 Hi-Mod, NSF 61 certified. 2.2 REINFORCING STEEL, WIRE FABRIC, TIE WIRE, AND METAL ATTACHMENTS.1 See Section MATERIALS.1 Provide non-shrink repair material for skim coats, filling bug holes and other horizontal applications less than 25 mm thickness using:.1 Sika Corporation: SikaTop 122 Plus, NSF 61 certified..2 Provide non-shrink repair material for formed or horizontal applications greater than 25 mm (minimum thickness varies by manufacture) using non shrink repair mortars specified below and extended with aggregates as recommended by manufactures:.1 Sika Corporation: SikaTop 122 Plus. NSF 61 certified.

7 15ECS-MI-01WA / TCN Page 7 of 13.3 Provide non-shrink repair material for non-formed vertical and overhead applications using the following materials:.1 Sika Corporation: SikaTop 123 NSF 61 certified..4 Crystalline waterproofing material for crack repair:.1 Xypex: Xypex Concentrate, Xypex Concentrate Dry-Pac, Xypex Patch n Plug, NSF 61 certified..2 Or approved alternate. 2.4 JOINT SEALANT.1 For expansion joint and other joint repair, use the following material:.1 Sika Corporation: Sikaflex 2c NS EZ Mix and Sikaflex 2c SL, NSF 61 certified.2 Sika Corporation: Sikaflex primer 429/ JOINT GASKET.1 For expansion joint or crack repair: Sikadur Combiflex by Sika Corporation 2.6 CRACK PENETRATING SEALER, AND INJECTION PORT OR CAP SEALER.1 Polyurethane.1 Crack Penetrating Sealer: low toxicity, two- component, 100% solid, polyurethane foam, NSF 61 certified.1 MME Multiurethanes 2.7 COMPATIBILITY.1 Ensure that all materials used are compatible. Provide written proof of compatibility. 3 Execution 3.1 EVALUATION AND ANALYSIS.1 A site visit for confirmation of the concrete deficiencies shall be carried out by the Engineer prior to the start of repair work. The Contractor shall provide a window of one week to allow the Engineer to perform this inspection..2 The site visit will confirm each deficiency shown on the Contract Drawings with regards to repair location, repair type, and repair length/area/volume. Any deficiencies shown on the Contract Drawings are base scope and should be included in the Contract Price.

8 15ECS-MI-01WA / TCN Page 8 of 13.3 In the event that adjustments including increase and deduction of repairs beyond those shown on the Contract Drawings are required, the provisional unit prices entered in the Form of Tender should be applied. The Contractor shall alert the Engineer prior to starting these repairs to facilitate agreement of quantity, measurement, and applicable provisional unit price..4 Commencement of work implies acceptance of existing conditions and assuming full responsibility for the finished condition of the work Repair Type 1 - Repairing small holes, seams, joints, spalls and other horizontal and vertical applications less than 25 mm ± 5mm thickness.1 Remove and clean efflorescence around the affected area..2 Sawcut the perimeter of the patches to provide a minimum 12 mm deep vertical surface, where possible. Do not cut into or damage any reinforcing bars..3 Remove all loose or spalling concrete (to a depth of 25 mm ± 5mm) until sound concrete is reached..4 Remove concrete in repair areas to a uniform depth as specified above..5 Apply bonding agent before patching grout in accordance with manufacturer s instruction..6 Finish of repair mortar shall be by steel trowel or match the existing condition..7 Carry out curing of repair mortar using clear liquid curing compound as specified and in accordance with manufacturer's recommendations..2 Repair Type 2 Delaminated and unsound concrete repair for formed applications greater than 25 mm ± 5mm with aggregates as recommended by manufactures.1 Remove and clean efflorescence around the affected area..2 Unsound, weak, or damaged concrete shall be removed. Loose particles, laitance, spalling, cracked, or debonded concrete and foreign materials shall be removed with hand tools unless otherwise noted..3 The perimeter of the patches shall be sawcut a minimum of 12 mm deep to provide a vertical surface where possible. Do not cut into or damage any reinforcing bars..4 The concrete in the repair areas shall be extend to a uniform depth of 25 mm beyond the layer of reinforcing steel..5 Loose concrete shall be removed from around exposed or deteriorated reinforcing steel..6 Removal shall extend along all reinforcing bars to the point where the exposed steel is essentially rust-free. Do not extend removal beyond the limits of the repair area except as authorized by the Engineer.

9 15ECS-MI-01WA / TCN Page 9 of 13.7 Exposed reinforcing steel shall be mechanically cleaned to bare metal and sandblasted to remove all loose and fractured concrete. Exposed steel in areas to be patched shall be painted with bonding agent..8 The reinforcement shall be sandblasted to SSPC-SP10 near white blast finish..9 The Contractor shall notify the Engineer of any steel members that have significant loss in cross-sectional area due to corrosion, cutting, or other damage. Damaged portions shall be mechanically cut away. Reinforcing steel to match existing shall be installed where existing reinforcing is badly corroded or damaged and shall include welding as directed by the Engineer. Lap splices shall be as required by code. If necessary, bars shall be fastened with tie wires..10 Apply bonding agent before patching grout in accordance with manufacturer s instruction..11 Place the concrete by an approved method and consolidate using pencil vibrators if applicable..12 Finish of repair mortar shall be by steel trowel or match the existing condition..13 Carry out curing of repair mortar using clear liquid curing compound as specified and in accordance with manufacturer's recommendations.3 Repair Type 3 Crack Repair by Rout/Patch.1 No water flow.1 Remove and clean efflorescence around the affected area..2 Rout out crack/construction joint in a u shaped slot 25 mm wide and 38 mm deep..3 Remove any loose material and saturate with water to a surface dry condition.4 Apply one slurry coat of Xypex Concentrate at a rate 0.8 kg/m^2 to the slot and a 150 mm wide strips on each side of the slot using a brush..5 While slurry is still tacky, fill slot to surface with Xypex Concentrate Dry- Pac. Apply Dry-Pac by gloved hand and compress tightly into the slot using a hammer and block..6 Wet the Dry-Pak surface lightly with water and apply Xypex Concentrate at a rate of 0.8 kg/m^2 over the repair area..7 Wet cure in accordance with manufacturer s recommendations for not less than two days..8 Refer to manufacturer s literature regarding mixing requirements and for application instructions..2 Against water flow.1 Remove and clean efflorescence around the affected area.

10 15ECS-MI-01WA / TCN Page 10 of 13.2 Rout out crack/construction joint in a u shaped slot 25 mm wide and 38 mm deep..3 Remove any loose material.4 Apply Xypex Patch n plug to half the depth of slot and for the full length of the cracks..5 Apply one slurry of Xypex Concentrate at a rate of 0.8 kg/m^2 in the slot over the patch plug and a 150 mm wide strips on each side of the slot using a brush..6 While slurry is still tacky, fill slot to surface with Xypex Concentrate Dry- Pac. Apply Dry-Pac by gloved hand and compress tightly into the slot using a hammer and block..7 Wet the Dry-Pak surface lightly with water and apply Xypex Concentrate at a rate of 0.8 kg/m^2 over the repair area..8 Wet cure in accordance with manufacturer s recommendations for not less than two days..9 Refer to manufacturer s literature regarding mixing requirements and for application instructions..4 Repair Type 4 Crack Repair by Injections.1 Polyurethane Injection Method.1 Remove and clean efflorescence around the affected area..2 Drill 9.5mm diameter holes at 45 degrees intersecting crack approximately 100mm below the concrete surface at 200mm intervals along both sides of crack alternately..3 Remove contamination from crack by vacuuming or flushing with water or other effective cleaning solution..4 Install the injection packers after proper surface preparation..5 Mix the polyurethane chemical grout in accordance with the manufacturer s instruction..6 Inject the prepared cracks with a minimum of 1725 psi in order to achieve max. filling and penetration without the inclusion of air pockets or voids in the polyurethane chemical grout..7 Begin the pressure injection at lowest packer with the manufacturer s instructions..8 Upon completion of the injection process, remove surface seal and injection ports by heat, chipping or grinding once epoxy resin has cured..5 Repair Type 5 Concrete Expansion Joint or Crack Repair.1 Remove and clean efflorescence around the affected area.

11 15ECS-MI-01WA / TCN Page 11 of 13.2 Apply Sikadur Combiflex SG on Expansion Joint as indicated on the Contract Drawings..3 Install Sikadur Combiflex SG in accordance with the manufacturer s recommendations..4 Prepare concrete surface on either side of the expansion joint by sandblasting or other approved mechanical methods. Deteriorated joint faces should be repaired to a smooth, sound surface prior to application. Remove all existing coatings, impregnations, surface treatments, curing compounds, laitance, dirt or other foreign material..5 Provide suitable equipment to dry concrete surface to allow installation of epoxy adhesive..6 The Sikadur Combiflex SG applicator shall have a minimum 5-year experience for the similar projects and shall be approved by manufacturer in writing..6 Repair Type 6 Removal Ex. Sealant and Install New Sealant on construction joints.1 Construction joint on wall:.1 Remove and clean efflorescence around the affected area on wall..2 Remove the extruded joint filler..3 Do not damage joint filler inside the joint groove..2 Construction joint on floor:.1 Remove and clean efflorescence around the affected area on floor..2 Remove the existing joint filler to create an approximately 35mm deep groove along the floor construction joints. Do not damage the existing joint filler beyond 35mm deep..3 Saw cut side of the joint groove 35mm deep to expose clean/sound concrete..4 Dry concrete surface along the joint groove to allow sealant installation..5 Prime joint groove sides with a sealant primer and apply appropriate backrod on the bottom of the groove (top of existing filler)..6 Apply and cure the new polyurethane sealant Sikaflex 2C/SL or approved alternate, in accordance with manufacturer s recommendations. Sealant material shall be NSF 61 certified..7 Apply sealant using gun with proper size nozzle. Use sufficient pressure to fill voids and joints solid. Superficial pointing with skin bead is not acceptable..8 Form surface of sealant with full bead, smooth, free from ridges, wrinkles, sags, air pockets, embedded impurities. Neatly tool surface to a slight concave joint.

12 15ECS-MI-01WA / TCN Page 12 of 13.9 Clean adjacent surfaces immediately and leave work neat and clean. Remove excess sealant and droppings using recommended cleaners as work progresses. Remove masking after tooling of joints..10 Apply the sealant when the substrate material temperature is above 5º C or approved by manufacturers..11 Prepare the concrete surface as per manufacturer s instructions to receive a minimum two coats of Sikagard EWL coating as per Contract Drawings..12 Control the concrete temperature and humidity during the construction joint repair per manufacturer s instructions..7 Repair Type 7 Removal of Anchors and Miscellaneous Metals.1 Miscellaneous metals (including anchor bolts) mounted on any surface that have been disconnected or are no longer used shall be removed by cutting/grinding. A flush surface shall be the result. Contractor shall confirm with Owner and Engineer prior to the removal of any item..2 Cut existing anchor bolts 25 +/- mm deep beyond concrete surface and patch the holes with grout refer to Repair Type 1..3 Restore the concrete surface to original. 3.3 POST REPAIR INSPECTION.1 Upon completion of the repairs, the Contractor shall immediately contact the Engineer to coordinate a site visit to inspect all repairs..2 The repairs shall be inspected for cracking, crazing, delamination, unsoundness and other defects. The finish, texture and surface tolerances of the repairs shall be inspected to verify that all requirements have been met. All repair areas exhibiting defects shall be repaired as directed..3 The Engineer will keep minutes from the Post Repair Site Inspection Visit and issue meeting minutes to Contractor and Owner to capture any deficiencies..4 Deficiencies shall be address by the Contractor at no cost to the Owner. 3.4 FINAL CLEANING.1 Refer to Division 1 for additional information pertaining to Final Cleaning (Section 01741)..2 No sooner than 72 hours after completion of the curing period and after joints are sealed, faces and other exposed surfaces of concrete shall be washed down with water applied with a soft bristle brush, then rinsed with clean water. Discolorations that cannot be removed by these procedures will be considered defective work. Cleaning work shall be done when temperature and humidity conditions are such that surfaces

13 15ECS-MI-01WA / TCN Page 13 of 13 dry rapidly. Adjacent surfaces shall be protected from damage during cleaning operations..3 All debris and supplies shall be removed from the repair areas upon completion of repairs and passing of the Post Repair Inspection. END OF SECTION