METHOD STATEMENT FOR WATER PROOFING OF UNDERGROUND CONCRETE STRUCTURES

The purpose of this Method Statement is to describe the methodology involved in application of protective coating (Bitumen Emulsion Paint) for underground concrete foundations and to details out the steps to be taken in meeting the technical standards and EHS requirements of Van Phong 1 BOT Thermal Power Plant.

Comment Response Sheet (CRS) Project Title Van Phong BOT Thermal Power Plant Project Document Title METHOD STATEMENT FOR WATER PROOFING OF UNDERGROUND CONCRETE STRUCTURES Document Type For Approval Document No VP1-0-L4-C-GEN-10027 Returned Status AC Prepared by CRS No VP1-0-L4-C-GEN-10027-A-CRS CRS Issued Date 12/05/2020 Engineer Construction Status O/C * Remarks No Section/ Page Owner’s Comment Response to Comment Review Date This should be more monitored before painted Lot added on revision B 12/05/2020 Closed O - Have any countable value to evaluate the thickness of this coating? - How to estimate the timing duration for drying each layer? Lot added on revision B 12/05/2020 Closed O Coating thickness is mentioned? Lot added on revision B 12/05/2020 Lot Closed O Additional Notes (if any) * O - Open, C – Closed Page of AP APPROVED Approved AC APPROVED WITH COMMENT Contractor to revise the correction and resubmit NA NOT APPROVED Revise the correction and resubmit before proceeding RE REVIEWED Information acknowledged with no comment For Approval RC REVIEWED WITH COMMENT Information acknowledged with comments Note: Approval or comment does not relieve the Contractor of all obligations covered under contract Discipline: Date: Civil 10 Jun 20 B 02-Jun-2020 For Approval J.H CHOI K.S KIM Y.H LEE A 06-May-2020 For Approval J.H CHOI K.S KIM Y.H LEE REV DATE DESCRIPTION Approved Checked Prepared OWNER VAN PHONG POWER COMPANY LIMITED PROJECT Van Phong BOT Thermal Power Plant Project Status □Approved □Approved with Comment □Not Approved □Reviewed OWNER’S ENGINEER Pöyry Switzerland Ltd EPC CONTRACTORS IHI–TESSC–CTCI–DHI CONSORTIUM PROJECT DOCUMENT No REV VP1-0-L4-C-GEN-10027 B DOCUMENT TITLE METHOD STATEMENT FOR WATER PROOFING OF UNDERGROUND CONCRETE STRUCTURES EPC EPC DOCUMENT No VP1-0-L4-C-GEN-10027 Doosan Heavy Industries and Construction REV B Page | VAN PHONG BOT THERMAL POWER PLANT PROJECT CONTENTS PREFACE 2 REFERENCE MACHINERY & EQUIPMENT RESPONSIBILITIES PROCEDURE AND SEQUENCE QUALITY CONTROL ENVIRONMENT, HEALTH AND SAFETY (EHS) GPS MEMBRANE SPECIFICATION 23 ATTACHMENT 25 Page | VAN PHONG BOT THERMAL POWER PLANT PROJECT 1.0 PREFACE The purpose of this Method Statement is to describe the methodology involved in application of protective coating (Bitumen Emulsion Paint) for underground concrete foundations and to details out the steps to be taken in meeting the technical standards and EHS requirements of Van Phong BOT Thermal Power Plant  Plant Project/Project : Van Phong BOT Thermal Power Plant Project  Company/Owner : Van Phong Power Company Limited (VPCL)  Contractor : EPC 2.0 REFERENCE  ASTM C309  GPS ‘s Specification 3.0 MACHINERY & EQUIPMENT No Description Angle Grinder Brush and Roller Measuring Tape Marking String Remark 4.0 RESPONSIBILITIES • It is overall responsibility of Project Manager to organize resources prior to perform construction activities aster project specification in compliance with the quality, schedule & safety requirements • EHS Manager will ensure in coordination with Site Engineer that all measure/construction taken shall be maintained till completion of job • It is the responsibility of Construction Manager/Site Engineer that construction activities are executed according to the relevant project specification in compliance with the quality, Page | VAN PHONG BOT THERMAL POWER PLANT PROJECT schedule & safety requirements • EPC will ensure that all works are performed safety according to the attachment • The relevant EPC Supervisor will ensure that the work is carried out in accordance with this method statement and project specification • The QC Inspector will ensure that the work is executed according to the requirements of quality dossier are fulfilled 5.0 PROCEDURE AND SEQUENCE 4.1 Bitumen Emulsion Paint 4.1.1Surface Preparation  All surfaces must be free of grease, oil and dust Very smooth surfaces should be roughened for better adhesion Loose rust, moss, lichens, crumbling cement, deteriorated fiber cement and degraded bituminous substances must be removed either mechanically or chemically  Surface faults such as blisters, holes and cracks should be cleaned out, then repaired with a flexible filler such as silicon, mastic, etc Small hairline cracks will be monitoring case by B case specification and proposal method to repair if cracks development, if not development can be painted with bitumen waterproofing emulsion by brush in, allow in dry then repeat until filled or at least sealed  Arises shall be rounded off and surface protrusions shall be grind down to ensure a smooth substrate  All standing water shall be removed from the concrete 4.1.2 Temperature Conditions  Before applying, the surface temperature must be within 5ºC - 40ºC If temperature is too high, surfaces should be cooled down by water Surface should be moist but water is not allowed to remain on the surface 4.1.3 Application Page | VAN PHONG BOT THERMAL POWER PLANT PROJECT  It is imperative that Bitumen Waterproofing Emulsion is applied to a clean surface to ensure a firm enduring bond to substrate  Application shall be by brush roller or squeegees on to the previously prepared substrate  Allow the first coat to dry before applying the second coat, allow the second coat to dry B before applying the third coat, in accordance with ASTM specifications Contractor can use coverage meter to check thickness, as the manufacture testing estimate the timing duration for drying each layer is 4-5 hours Bituminous final coating B Bituminous coating Primer coating Concrete Structure 6.0 QUALITY CONTROL •The Site Inspection and Test Plan (ITP) for this work summarizes various characteristics to be checked The concerned Site Engineer/Foreman will be responsible to ensure stage wise Page | VAN PHONG BOT THERMAL POWER PLANT PROJECT compliance for this operation and the Site QA/QC Engineer/Inspector will carry-out quality control checks and report the inspection results 7.0 ENVIRONMENT, HEALTH AND SAFETY (EHS) 7.1 Responsibilities •PM/EHSS Officer shall ensure that all work is undertaken in accordance with the specified work scope •Safety training should be conducted to all personnel assigned at site prior to commence any work •All personnel should know the locations of fire extinguishers, communications, manual alarms •All personnel should be aware of assembly points, escape routes, emergency contact numbers •Personal Protective Equipment (PPE) shall be worn at all times •Good housekeeping shall be observed in work areas •Construction wastes shall be segregated and disposed to an approved dump yard area •Adequate lighting equipment when working night time •Ensure all workers and equipment working overtime are properly accounted and obtained permit/approval from Doosan EHS Manager prior to carry-on works •Periodic refresher trainings, tool box talk and audit shall be conducted 7.2 Safety •Personal Protective Equipment (PPE) will be issued to all workers such as safety shoes, hard hat, working gloves, earplug, safety goggles, reflective vest and safety harness for workers who will be assigned •Wearing of the basic PPE will be enforced fully Page | VAN PHONG BOT THERMAL POWER PLANT PROJECT 7.3 Job Safety Analysis APPENDIX A JOB DESCRIPTION: Step / Activity 1.Site Preparation Painting Ceiling, Wall and Floor activity Work Task Potential Hazard Consequences Revision : Risk Assess ment Hazard Control Residual Risk I L R I L R Additional Control : Action Required by : 1.1 PTW applying 1.1.1 Hazards and safety precautions unidentified -Incompliance with DVN permits to work requirements -PTW is not granted -Down time D M -Competent PTW coordinator assigned -Supervisors ensure the right information be write and thick on the certificate -Permit applicant ensure RA and AA sign the daily approval part before proceed activity at site B L Refresher PTW training Site Supervisor 1.2 Tools & equipment Inspection 1.2.1 Improper body posture -Back Injury D M - Implement proper body posture/method for manual handling B L Ergonomic training - Brief to workers related to back injury prevention Site Supervisor -Use buddy system as help of friend or use machinery - Use legs not back to lift -Do not manual carrying material with over 25kg alone - Use mechanical lifting whenever possible Page | VAN PHONG BOT THERMAL POWER PLANT PROJECT 1.3 Equipment/ tools and material mobilizatio n to worksite 1.4 Loading and unloading materials (manual handling/Lif ting) 1.2.2 Electrocution -Physical Injury D M -Ensure the power connection been unplug from outlet before inspection -Only authorized person are allowed to perform inspection activity B L 1.3.1 Sharp edges -Physical injury D M B L Refresher training (hand injury) Site Supervisor 1.3.2 Uncertified equipment -Equipment not granted to use D M -Use proper equipment for the job -all equipment must be in good condition -No modification on tools and equipment are allowed to be inspect B L Quater colour coding system be implemented Site Supervisor 1.4.1 Improper body posture Musculoskeletal disorder -Back pain D M - Implement proper body posture/method for manual handling -Implement buddy system during perform manual handling B L Ergonomic training -Brief to workers related to back injury prevention Site Supervisor B L Refresher training (hand Site Supervisor -Brief to workers regarding on hand injury prevention -To wear hand protection (hand gloves) - Use legs not back to lift -Do not manual carrying material with over 25Kg alone - Use mechanical lifting whenever possible 1.4.2 Sharp edges -Physical injury D M -Brief to workers regarding on hand injury prevention Page | VAN PHONG BOT THERMAL POWER PLANT PROJECT -To wear hand protection (hand gloves) 1.5 Loading and unloading materials Lifting using crane (mobile/ mounted) injury) 1.4.3 Pinch point -Hand/finger injury D M -Workers must aware of pinch point hazard during handle the material -Use a suitable hand glove B L Awareness training for pinch point Site Supervisor 1.5.1 Lorry Crane topple due to unstable ground -property damaged -physical injury C M -access for vehicle moving must be level and compact -Lorry must be inspected with colour coding - Operator must have full attention and not allowed to use cell phone - Use flagmen to direct equipment operators, keep all other workers clear of operating equipment - To follow speed limit of 10km/h - Contractor to ensure vehicle in good condition B L Quater colour coding system be implemented Site Supervisor Lifting Crew Operator 1.5.2 Mechanical Failure -property damaged -physical injury C M -Crane must be inspected by authorized person Maintenance of crane to be once a month in according to manufacturer’s instructions - Contractor to ensure vehicle in good condition -Crane must be inspected with colour coding - Operator must have full attention and not allowed to use cell phone B L Quater colour coding system be implemented Site Supervisor Lifting Crew Operator Page | VAN PHONG BOT THERMAL POWER PLANT PROJECT surface) 3.1.5 Mastic splash to eyes - Eyes injury C M -Give a training to the worker how to handle chemical -To provide portable eye wash -To wear safety goggle to perform this activity C L Site Supervisor 3.1.6 Paint bucket topple -Environment effect C L -Ensure all the chemical put in the tray -Not put paint bucket around access and egress area B L Site Supervisor 3.1.7 Lack of oxygen -Physical injury C M -Ensure inside building area is free from any flammable/toxic atmosphere and has sufficient oxygen for normal breathing -Ensure to provide two way ventilation(suck in/suck out) B L Site Supervisor 3.1.8 Fall from height -Physical injury C H B M -Resfresher WAH training Site supervisor -Proper elevated working platform to be built -Safety net to be installed underneath the elevated working platform if practicable -Gap between elevated work platform and wall must not be greater than 300 mm -Covering/hard barricaded with warning sign for opening on elevated work platform Page | 13 VAN PHONG BOT THERMAL POWER PLANT PROJECT -No unauthorized removing cover of opening -Sufficient lighting for the whole elevated working platform (100lux working area/50lux access) -All personnel to be trained with WAH -All personnel compulsory to use safety harness with DOUBLE LANYARD on elevated work platform -Use provided access and egress and no taking shortcut -Use free hands while climbing ladder (3 points contatcs) Placing 4.1 Place emulsion on surface 4.1.1 Chemical contact -Inhalation effect -Eye injury -Skin irritation D M -To brief SDS to the workers before start -To ensure continuous ventilation for inside building area -To provide portable eye wash -to wear proper hand gloves (chemical gloves), safety glass and face mask (N95) C L -SDS training Site Supervisor 4.1.2 Improper body posture -Muscle strain and body fatigue C M -Implement buddy system during activity -Proper body posture during material handling B L Ergonomic training Site Supervisor 4.1.3 Chemical spillage -Environment effect C M -Ensure all the skim coat put in the tray B L Chemical handling Site Supervisor Emulsion Paint Page | 14 VAN PHONG BOT THERMAL POWER PLANT PROJECT -Chemical container must close with cover all the time when not in use awareness training 4.1.4 Paint splash to eyes - Eyes injury C M -Give a training to the worker how to handle chemical -To provide portable eye wash -To wear safety goggle to perform this activity C L 4.1.5 Paint bucket topple -Environment effect C L -Ensure all the chemical put in the tray -Not put paint bucket around access and egress area B L Site Supervisor 4.1.6 Lack of oxygen -Physical injury C M -Ensure inside building area is free from any flammable/toxic atmosphere and has sufficient oxygen for normal breathing -Ensure to provide two way ventilation(suck in/suck out) B L Site Supervisor 4.1.7 Fall from height -Physical injury C H B M -Resfresher WAH training Site supervisor -Proper elevated working platform to be built -Safety net to be installed underneath the elevated working platform if practicable -Gap between elevated work platform and wall must not be greater than 300 mm -Covering/hard barricaded with SDS training Site Supervisor Page | 15 VAN PHONG BOT THERMAL POWER PLANT PROJECT warning sign for opening on elevated work platform -No unauthorized removing cover of opening -Sufficient lighting for the whole elevated working platform (100lux working area/50lux access) -All personnel to be trained with WAH -All personnel compulsory to use safety harness with DOUBLE LANYARD on elevated work platform -Use provided access and egress and no taking shortcut -Use free hands while climbing ladder (3 points contatcs) Placing Epoxy Paint 5.1 Apply epoxy paint on the floor Site Supervisor 5.1.1 Chemical contact -Inhalation effect -Eye injury -Skin irritation D M -To brief SDS to the workers before start -To ensure continuous ventilation for inside building area -To provide portable eye wash -to wear proper hand gloves(chemical gloves), safety glass and face mask (N95) C L -SDS training 5.1.2 Improper body posture -Muscle strain and body fatigue C M -Implement buddy system during activity -Proper body posture during material handling B L Ergonomic training Site Supervisor Page | 16 VAN PHONG BOT THERMAL POWER PLANT PROJECT 5.1.3 Chemical spillage -Environment effect C M -Ensure all the skim coat put in the tray -Chemical container must close with cover all the time when not in use B L Chemical handling awareness training Site Supervisor 5.1.4 Paint splash to eyes - Eyes injury C M -Give a training to the worker how to handle chemical -To provide portable eye wash -To wear safety goggle to perform this activity C L SDS training Site Supervisor 5.1.5 Heat stress /Dehydration - Collapsed and faint C L - Enough rest and fit before start the work - Sufficient supply of fresh and clean drinking water to avoid dehydration B L -Heat stress campaign and awareness training Site supervisor 5.1.6 Paint bucket topple -Environment effect C L -Ensure all the chemical put in the tray -Not put paint bucket around access and egress area B L Site Supervisor 5.1.7 Lack of oxygen -Physical injury C M -Ensure inside building area is free from any flammable/toxic atmosphere and has sufficient oxygen for normal breathing -Ensure to provide two way ventilation(suck in/suck out) B L Site Supervisor Page | 17 VAN PHONG BOT THERMAL POWER PLANT PROJECT Painting wall 6.1 Painting wall using Gondola platform 6.1.1 Mechanical Failure -property damaged -physical injury C M - Operator must have full attention and not allowed to use cell phone -Gondola platform must be inspected by authorized person Maintenance of gondola platform to be once a month in according to manufacturer’s instructions - Contractor to ensure equipment in good condition - gondola platform must be inspected with colour coding B L Quater colour coding system be implemented Site Supervisor Operator 6.1.2 Broken Gondola platform -property damaged -physical injury C M -Must to daily checklist -Provide warning sign “No Entry, Authorized Person Allowed” -Signalman to be Standby -Proper setting anchor point follow MS -Follow SWL -Daily checking wire rope before you B L Quater colour coding system be implemented Site Supervisor Lifting Crew Operator 6.1.3 Falling from bucket -Physical injury -Fatality C H B M -Resfresher WAH training -Gap between elevated work platform and wall must not be greater than 300 mm -No unauthorized personnel to control boom lift panel -All personnel to be trained with WAH -All personnel compulsory to use Site supervisor Page | 18 VAN PHONG BOT THERMAL POWER PLANT PROJECT safety harness with DOUBLE LANYARD in the bucket 6.1.4-Fall from height People injury C H B M -Proper elevated working platform to be built -Safety net to be installed underneath the elevated working platform if practicable -Gap between elevated work platform and wall must not be greater than 300 mm -Covering/hard barricaded with warning sign for opening on elevated work platform -No unauthorized removing cover of opening -Sufficient lighting for the whole elevated working platform (100lux working area/50lux access) -All personnel to be trained with WAH -All personnel compulsory to use safety harness with DOUBLE LANYARD on elevated work platform -Use provided access and egress and no taking shortcut -Use free hands while climbing ladder (3 points contatcs) B M -Resfresher WAH training B L Site supervisor Page | 19 VAN PHONG BOT THERMAL POWER PLANT PROJECT Night work / extended hours Job Completion 7.1 Painting at night 8.1 Housekeepi ng activity 7.1.1 Poor lighting (Night Work) -Physical injury -Fatality -Provide sufficient lighting (100 lux for working area, 50 lux for access way) -To wear suitable PPE (e.g clear goggles) -Conduct night Toolbox Talk Site Supervisor 7.1.2 Biological hazard (poisonous insect, reptile and animal) -Physical injury -Fatality Site Supervisor B L -Emergency contact numbers to be available at site and brief to all workers -First aider to be available at site B L -Monitoring of workers Overtime Site Supervisor B L -All workers to be vigilant at all time -To ensure work area clean and tidy prior to start work -Observe presence of poisonous insects, reptile and animal, which may attracted to light B L -Management of fatigue -Rotaring manpower 7.1.3 Workers overwork -Physical injury -Depression 8.1.1 Material obstruction -Physical Injury -Property damage C M -Safe access and egress to be maintain -Proper material arrangement -Ensure all loose material keep in bag and container -Keep all material at designated area and barricade with a signage -Wear proper PPE B L 8.1.2 Sharp edges -Physical injury D M -Brief to workers regarding on hand injury prevention -To wear hand protection (hand gloves) B L Site Supervisor Refresher training (hand injury) Site Supervisor Page | 20 VAN PHONG BOT THERMAL POWER PLANT PROJECT 8.1.3 Slip/trip/fall -Physical injury D M -Proper access and elevated working plaform to be provided -Sufficient lighting to be provide -Good housekeeping to be maintain B L Site Supervisor 8.1.4 Drop object -Physical injury -Property Damage D M -Equipment/tool to be properly secured/ handled/tight B L Site Supervisor Page | 21 VAN PHONG BOT THERMAL POWER PLANT PROJECT RISK CLASSIFICATION MATRIX Severity/Mức độ ảnh hưởng IMPACT TÁC ĐỘNG/ẢNH HƯỞNG/HẬU QUẢ LIKELIHOOD KHẢ NĂNG XẢY RA LOW RISK Rủi ro thấp Minor/ Nhẹ Moderate/ Vừa phải Major/ Lớn Catastrophic/ Nghiêm trọng People/ Đ/v người Slight Injury Minor Injury Major Injury Single Fatality Multiple Fatalities Environment/Đ/v môi trường Assets/ Đ/v tài sản Slight Impact Minor Impact Localized Impact Major Impact Massive Impact Slight Damage Minor Damage Local Damage Major Damage Significant Damage Slight Impact Limited Impact Major National Impact Happens several time per year in the location E1 E2 Considerable Impact E3 E4 Major International Impact E5 Happens several time per year in the industry D1 D2 D3 D4 D5 Incident has occurred in the company C1 C2 C3 C4 C5 Heard of incident in the industry B1 B2 B3 B4 B5 Never heard of in the industry A1 A2 A3 A4 A5 Reputation/ D0/v danh tiếng E Almost Certain/ Gần chắn D Likely/ Rất Có thể xảy C Possible/ Có khả xảy B Unlikely/ Khơng xảy A Remotely Likely/ Rất hiếm/khó xảy Insignificant/ Cần xem xét MEDIUM RISK Rủi ro mức trung bình HIGH RISK Rủi ro cao VERY HIGH RISK Rủi ro cao Page | 22 VAN PHONG BOT THERMAL POWER PLANT PROJECT 8.0 GPS MEMBRANE SPECIFICATION Page | 23 VAN PHONG BOT THERMAL POWER PLANT PROJECT Page | 24 VAN PHONG BOT THERMAL POWER PLANT PROJECT # ATTACHMENT: WATERPROOFING CONSTRUCTION METHOD USING GPS® MEMBRANE MATERIAL Page | 25 GPS VIETNAM COMPANY LIMITED Address: Van Giang – Dai Nghia Town – My Duc District – Hanoi City Transaction office: No 64/54 Le Quang Dao – Phu Do Ward – Nam Tu Liem District – Hanoi City Tel: (024) 6282 599 - Fax: (024) 6282 600 - Hotline: 0962 598 999 WATERPROOFING CONSTRUCTION METHOD USING GPS® MEMBRANE MATERIAL Image for illustrative purposes only I Requirement for concrete surface before waterproofing work - Dismantling, moving and cleaning obstacles: formwork, wood, steel, - The defects of concrete such as sockets, holes should not be covered with cement mortar before the waterproofing treatment - Water supply and drainage pipes through concrete or technical boxes should be located and installed with plaster or concrete II Waterproofing construction process Preparation of the waterproofing surface - Chopping, chiseling off layers of cement mortar and excess concrete to show the surface of structural concrete with hand tools: chopping hammer, chipping hammer, sharp broaching - Before applying bituminous based screeds, we should saturate concrete with the water to avoid being drained, leading to the fact that the waterproofing material will not penetrate deeply into the concrete body to create links (but water remaining on concrete surface is avoided) - Waterproofing reinforcement treatment of sockets, pores, cracks, steel cavities on concrete surface with GPS® Latex/GPS® Latex TH oil slurry and GPS® Mota16 concrete repair mortar Page of 2 Waterproofing construction process + Lining: Apply or spray evenly on the surface with a density of 0.3 kg/ m2 to allow the lining to dry completely before applying the next coating + Coating: - Coating 1: Apply GPS® Membrane directly to the lining with a brush or sprayer with a density of 0.6 kg/ m2 - Coating 2: Apply GPS® Membrane directly to the lining with a brush or sprayer with a density of 0.6 kg/ m2 *Product norm table Product name Description Consumption density GPS® Membrane Lining 0,3 kg/m2/ layer GPS® Membrane Coating 0,6 kg/m2/ layer GPS® Membrane Coating 0,6 kg/m2/ layer Total 1,5 kg/m2 ( for mm thickness after drying) We hope to be cooperated with You! 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