Michael Pacholok, Director Purchasing and Materials Management Division City Hall, 18th Floor, West Tower 100 Queen Street West Toronto, Ontario M5H 2N2

Victor Tryl, Manager Professional Services

March 24, 2015 Posted in PDF (16 Pages)

ADDENDUM NO. 5 REQUEST FOR TENDER NO. 267-2014

CONTRACT NO. 14FS-04WP HUMBER TREATMENT PLANT - DIGESTERS 9 AND 10 REHABILITATION

CLOSING: 12 NOON (LOCAL TORONTO TIME), MARCH 31, 2015

Please refer to the above Request for Tender (RFT) document in your possession and be advised of the following. INFORMATION AND REVISIONS 1. The following scope of work is to be added to the Contract works: a. Drip Trap Installation in the Gas Compressor Building Basement

TECHNICAL SPECIFICATIONS Technical Specification Sections shall be amended as follows: 1. Specification 15205 Revisions: Add in the following clause as 2.2.M “All valves shall have open closed position indication on the valve operator that is clearly visible from the floor”. Add the following sentence to the end of clause 2.6 I: As an equal to the Velan Digester Gas Valves, Bray Series 40/41 Lug Design valves certified to CGA 3.16 will be allowed in lieu in Velan SB-150 valves for digester gas service. Provide make up spool with flanges for all butterfly valve installations. 2. Drip Trap Installation in the Gas Compressor Building Basement a. Provide one (1) drip trap in the Gas Compressor Building basement at the North end of the 300 mm diameter digester gas collection header. Install drip trap in location as directed by CONTRACT ADMINISTRATOR.

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b. Refer to figure 1 - Gas Condensate Drip Trap Installation Schematic attached to this Addendum #5 for drip trap installation information. The piping and valve installation must meet the requirements of the Code for Digester Gas. Route drain piping to nearest floor drain for sediment traps approximately 5 meters away.

c. Insert the following product information for Low Pressure Condensate Drips traps into Specification 11386:

2.6 LOW PRESSURE CONDENSATE DRIP TRAPS

A. Description: Equipment for collection and automatic drain of digester gas condensate from the process stream; designed and constructed to prevent digester gas from escaping while draining.

B. Construction: 1. Provide 356 T6 low copper cast aluminum pressure body, rated for 34.5 kPag

maximum working pressure. 2. Stainless steel internal working parts including valves and hardware. 3. Inlet and outlet connections: 25 mm (1 inch) NPT. 4. Reservoir size: 5.7 L. 5. Electric valve actuators, high torque, with build-in motor overload protection.

C. Control System: 1. Provide shop wired, complete control system linking valve actuators to control

condensate drainage based on time. Provide each drip trap with a stand alone, dedicated control system (panel or assembly). Operator control devices shall be readily accessible for all control functions and settings. a. Control System THR-DG-CP-0003.

2. Provide products to meet the specified features and operating conditions as shown on the Drawings, in accordance with Section 16946 Electrical Requirements for Packaged Systems, and as specifically listed under this Section: a. Control system, actuators, and complete assembly shall be rated for

installation in Class 1, Div. 1, Group D (Digester Gas) hazardous locations. b. Control system shall be provided only with a 15 A, 120 VAC (plus or minus

10 percent), 60 Hz, 1 phase, 2 wire plus ground power feeder. Location of this power supply is Panel DP-GCA in Compressor Building Electrical Room; connect to circuit #27.

c. Provide two threaded NPT connections; one for power and one for control signals.

3. Control System Functional Requirements: a. Manual and automatic control. b. In manual mode operator can select FILL or DRAIN valve to open. c. In automatic mode control system performs fill/drain cycles based on internal

cycle timer(s). d. Drain and fill valves control shall be mutually exclusive; opened valve has to

close before the other one is allowed to open. Minimum drain and fill time shall be 15 minutes timer adjustable up to 10 hours.

e. Alarm and monitoring contacts. 4. Control System Operator Interface Devices:

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a. Fill-Drain-Auto selector switch. b. Fill valve mechanical position indicator. c. Drain valve mechanical position indicator. d. Timer(s) adjustment device.

5. Supervisory System Interface. Control system shall provide and accept (as a minimum) following signals: a. Provision for external system safety shutdown interlock (dry contact; Off

0 shutdown, On 1 OK; maintained): Not Applicable. b. Analog inputs (4 to 20 mA, 24 VDC): Not Applicable. c. Analog outputs (4 to 20 mA, 24 VDC): Not Applicable. d. Discrete inputs (120 VAC control power from this panel; Off 0, On 1;

maintained): Not Applicable. e. Discrete outputs (dry contacts, minimum 2 A at 120 VAC/24 VDC; Off

0 stopped/closed, On 1 running/opened; maintained): 1) Drip trap fill cycle status. 2) Drip trap drain cycle status. 3) Alarm - common fault.

f. Network Communication via Ethernet/IP (monitoring/control): Not Applicable.

6. Testing: Perform standard, performance tests of the drain trap and control system at the factory.

D. Provide sediment traps as manufactured by Varec Biogas Model 246AT, supplied by Westech, contact Jerry D’Ortenzio 905-601-3192, e-mail jerry@westch-ind.com.

QUESTIONS AND ANSWERS The following questions were received from prospective bidders regarding the contract documents: Q1: Drawing 1021-2013-12-16-M4 – Plan view – 900mm Access Manhole Covers – Please provide additional information regarding the work for the existing covers, including “Custom Steel Plate on interior Surface” advising plate material type, thickness, etc. A1: 900mm access manhole cover material shall be ASTM A240 – 316/316L stainless steel plate, 12mm thick with bolt pattern cut to match existing bolt holes in mating flange on digester penetration. No coating on cover plate is required. Q2: Please confirm that Val-Matic can be added as an approved supplier for the Plug Valves for Sludge Service (Section 15205 Item 2.8). Val-Matic Plug Valves fully meet the specification and have been provided to Wastewater Plants for use on Sludge Lines throughout the province of Ontario and specifically the City of Toronto and the Humber Treatment Plant. A2: Val-matic is an acceptable alternative valve manufacturer for Specification 15205 Item 2.8. Q3. Please confirm that the eight (8) 150 mm Plug Valves are to be pneumatically actuated, with new cylinders, regulators, solenoids and limit switches, similar to the Knife Gate Valves that are being replaced. A3: Correct, the eight (8) new plug valves replacing knife gate valves shall be replaced with new pneumatically actuated operators. (THR-DIG-V-1033, THR-DIG-V-1034, THR-DIG-V-1035, THR-DIG-V-1038, THR-DIG-V-0933, THR-DIG-V-0934, THR-DIG-V-0935, THR-DIG-V-0938).

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Q4: On Drawing M1 on valve schedule under heading type, some valves are specified with actuators. Are they pneumatic or electric?

A4: All valve actuators shall be pneumatic.

Q5. On drawing M6 on valve schedule under heading existing type, some valves call for operator to be replaced, but under but under heading replacement type just a valve is called for, please clarify.

A5: All valves that have existing actuators are to be replaced with new valves complete with new actuators, solenoids, and controls as per the specification.

Q6: On drawing M2 it tells us to install a 300mm short pattern ball valve, is this contractor supplied, If it is please provide spec, and what install type it is.

A6: Install Short Pattern Velan SB-150 as per Specification 15205. No existing flanges are in the piping. Contractor to cut in new valve, complete with flanges into the piping.

Q7: On Drawing M2/3 it tells us to install a 300mm free issue ball valve is this included on valve Schedule.

A7: Yes, See Replacement Type for “Free Issue”.

Q8: On drawing M5 it tells us to remove two valves and install spools, please provide sizes and material spec for spools.

A8: Spool piece shall meet the requirements for digester gas piping, as per Specification 15200.

Q9: Specification for large bore digester gas ball valves call for a spool to be installed on the valve by the valve manufacturer, is this correct?

A9: Full Port ball valves do not require spool pieces to be manufactured.

Q10: On drawing M1 it tells us to remove two PRV’s and install spools, please provide sizes and material spec for spools.

A10: This work is no longer required in this Contract. Delete this note.

Q11: On Drawing M5/6 it tells us that valves on sludge lines are to be cement lined the valve specs don’t call for any lining, but the pipe spec calls for ceramic epoxy lining, please advise if the sludge valves need lining and what kind.

A11: Follow the specification for the valves as per Specification 15205.

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Q12: In Section 02228 please provide the contact information for the pump manufacturer. A12: The pump is an Essco model 6 x 12 HDPM. Pump name plate information is as follows: 881 gpm @ 36 ft head, 1170 rpm with a 12” impeller. Q13: In Section 15200 2.6 replacement of ductile fitting please provide a drawing showing the locations and number of fittings to be changed out. A13: No fittings are required to be replaced as part of this Contract. Q14: In section 15204 2.2 please provide a sketch for the five sample valves for each sludge meter. A14: No sample valves are required as part of this contract. Q15: Please provide a spec for 300x300 louvers shown on drawing M15. A15: Louver shall be stationary blade, aluminum construction, Greenheck Model ESJ-401 or equal. Q16: On drawing M15 on detail 4 shows 2 valves to be installed please provide a spec for these valves A16: Valves shall be digester gas ball valves as per Specification 15205. Q17: Section 15200 – Item 2.4 – Stainless Steel Piping – General Service – Item 2.4.C (screwed fittings) does to match the stainless steel fittings as outlined in Item 2.4.F – Materials Description. Can you please clarify the pipe schedule and fittings type, for the various pipe size ranges for this service. A17: Provide all piping under 50 mm as threaded fittings, provide all piping 50 mm and larger as welded / flanged. Pipe under 50 mm shall be 316 stainless steel Schedule 40 ASTM A312/A312M. Piping 50 mm and above shall be Schedule 10 ASTM A312 /A312M. Q18: Since there are some repair work for digester #7 and #8 too as per the drawings, Will those digesters be shut down during the construction work? A18: Digester #7 and #8 will be active during the Contract work period. Q19: Pls clarify what kind of material at outside of existing 2700mm trunk sewer shown 0.5m thick on drawing C5? A19: Drawing C5 Sections A and B illustrate the waterproofing membrane overlapping the concrete surfaces on either side of the joints by 0.5m. Refer to Section 07515, 2.2 A for waterproof membrane material. Q20: Who will be responsible for all the cost of testing & inspection? G.C or Owner? A20: Third party quality control inspection and testing for the City will be paid for by the City. Any third party testing required by the Contractor will be paid for by the Contractor.

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Q21: What is the schedule for this project? A21: The Bidder is to fill in the number of weeks to complete the whole of the work as indicated in Section 3 - Tender Submission Package, Pricing Form page 3-9. Q22: Spec section 02300-3.6-S-3.b is asking 0.6m cover, but as per the proposed elevation C3 & C4, the new cover thickness will be only about 300mm above the existing digester roof, pls clarify. A22: Cover is to be placed as proposed on drawings C3 and C4. Q23 Drawing M1 – Digester Gas Schematic notes 2 PRV’s to be replaced with pipe spools. Please specify line size of PRV’s. A23: Refer to Question 10 response. Q24: Drawing M1 (Plan View) – Shows new 1” waterline to be installed. Detail 4 (M14) indicates that new water line is to be field routed to 14 sediment traps. Please specify the locations of where this line will tie into and the distance as no scale is specified on the drawing. A24: The water lines will tie into 11 existing sediment traps (for Digesters 1 to 8) and 3 sediment traps to be replaced under this Contract (for Digesters 9 &10). The distance from gridline 2a to gridline 8 is approximately 41 meters, The distance between each gridline from gridline 3 to gridline 8 is approximately 7 meters. Q25: Drawing M1 – Flow elements are to be replaced as shown with new pipes and connection pieces. Please specify the scope of the demo and replacement of pipe spool. Drawing does not indicate pipe size (confirm entire line size is 75mm as indicated on drawing M14, Detail 2). A25: Line size for flow meter piping is 75 mm with an existing Kurtz flow meter installed. Q26: Drawing M4 - 26 bubble generators to be replaced under the contract. Please provide existing dimensions and weights of existing units for removal. A26: Only the bubble generator box, and associated ancillary components / piping are to be replaced (bubble generator retrofit only), not the entire draft tube for the mixing system (See 11385 2.7B). The bubble generator system shall be made from 3.175 mm thick 316 stainless steel instead of 6.35 mm thick as indicated. Weights of equipment can be determined from the named manufacturer in the specifications. In 11385 2.6.A – All fasteners shall be 316 stainless steel instead of 304 stainless steel as indicated. In 11385 2.7 C – Pressure gauges shall be differential pressure gauges, range in kPa. In 11385 2.7 add in section D:

Two (2) special omega slip tight pipe guide assemblies in AISI 304 for each draft tube mixer. U-Bolt type pipe guide assemblies are not acceptable.

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Q27: Drawing M4 and specification 11385 requires 2 x 1200mm x 1200mm access hatch, 1 x 1650mm x 900mm weir box, as well as 1 x 1050mm x 1650mm tall side wall access door to be installed. Please provide drawing details and information on materials of construction. Please also indicate the location of access door and weir. A27: Specification Section 11385 details the requirements for the new digester gas mixing equipment. The note on drawing M4 identifies replacement of the gaskets/seals on the digester openings including 2 x 1200mm x 1200mm access hatch, 1 x 1650mm x 900mm weir box, as well as 1 x 1050mm x 1650mm tall side wall access door. The side wall access door is located inside the digester access chambers at the bottom of the digester. The weir is located at the top of the digester in the vicinity of the 900 mm diameter digester access holes. Q28: Section B, Drawing M5 – Indicates new 40mm stainless steel piping and valves to be installed. Please provide scale for drawing and tie in point as it is not clearly identified on the drawing. Is this line typical for two scrubbers? A28: The piping is typical for two scrubbers. Each connection will be into existing threaded ports on the scrubbers. Connect new water line at floor of scrubber building replacing existing water line. Q29: Drawing M8, Spec Section 02228 – 4 sludge heating pumps are to be dismantled and cleaned by pump manufacture. Please indicate pump manufacture. A29: Refer to Q12/A12 above. Q30: Drawing M13 - Please provide scale so that pipe lengths can be determined. A30: The mechanical piping conduit in section “A” is 6 meters wide. The plan of digester routing for the 300 mm diameter pipe will require an approximate run of 40 meters of pipe to connect the existing 300 blind flange into the 9/10 piping transition above grade. Q31: Drawing M19- Please confirm drawing scale so that length of Airline can be determined. A31: Both sections are drawn to a scale of 1:50.  Q32: In addendum #2 for compressed air lines. Please provide a sketch for the tie-in points, the length of the run and pipe size. A32: Piping is to be field routed from tie in point in the building to each valve. All tie in points shall be at the sample sink in each building. Piping will be 25 mm in size coming into building, all piping runs will be as required to control each valve. Q33: On drawing M-19 addedum#2 please provide the valve sizes for the new actuators required. A33: Refer to the Valve and Actuator Summary Table in Addendum #2. Q34: Drawing 1021-2013-12-27 - M15 - Detail 4 - Bubble Frequency Sensor Piping - Indicates new 2" Dia. Piping off of existing header. During the site walk there was a set of 2" dia. orifice flanges, can these items be re/used and re-installed? If not, please provide specifications of the orifice flanges, rating and orifice plate specifications.

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A34: The orifice flanges and gauges are to be reused and installed as they are currently located. The differential pressure gauges are to be relocated as needed to accommodate the new bubble frequency sensor installation. Q35: Drawing 1021-2013-12-27 - M15 - Detail 2 - Is the new 3-way valve in the Digester Gas Dome / Hut, free issue? If not please provide specification for the 3-way valve. A35:Refer to Specification Section 11386 – Digester Gas Equipment. Q36: Drawing 1021-2013-12-27 - M15 - Detail 2 - The existing Flame arrestor in the Gas Dome / Hut appears to have the discharge connection blanked off, is this correct, or is the outlet flange left open ended? Please advise. A36: The existing flame arresters and pressure release valves are to be reinstalled directly on the new 3-way valve, discharging directly into the gas dome. There is no blank on the pressure relief valves. Q37: Are cored holes through the Scrubber building walls for the new 2" digester gas piping required to be scanned? Please advise. A37: All holes or openings required in existing concrete shall be cut or cored. Prior to cutting or coring the wall or slab, employ radiography to locate suitable locations for penetrations. Refer to Specification section 01700 part 1.4 N. Q38: Please advise requirements for Site orientation (Length of time required) and availability through the work week, for subcontractors. A38: The Site Safety orientation is currently held every Tuesday at 8:30 am and Thursday at 11:30am and is approximately 2 hours in duration. Q39: Can we have another site visit to review electrical cable tray routing to each electrical panel. Note that we had insufficient time review Add #2 for this scope of work at the first site visit. A39: An additional site walk will not be arranged. Q40: Drawing 1021-2013-12-23 M11 - please clarify if the disconnect and removal of power and control wiring is to a local junction box. If not please provide drawings to the location for distance of removal of cables. A40: Cable removal shall be only to local junction box. Q41: Drawing 1021-2013-12-42 E10 - please provide drawing for the distance to the location for Panel LP-B. A41: Panel LP-B is located on the East wall of the Gas Compressor Building Electrical Room at ground level. The approximate distance to Panel LP-B is 70 meters. Q42: Drawing 1021-2013-12-43 E11 - This drawing is not to scale, please provide drawings for the distance to the location for the panels THR-PLT-RPU -0010 , THR-PLT-RPU -0011 and THR-PLM-RPU -0010.

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A42: The approximate horizontal distance between the RPU Panels and the furthest wall of North Boiler Building is 25 meters. Q43: Please verify that the mezzanine floor drawings E5, E6 & E7 are the first level directly below the Foam Scrubber Buildings. A43: Correct, the mezzanine level is the first level below the foam scrubber buildings for Digesters 1 to 8. The mezzanine level stops at Digester 7 and 8 and does not continue into the Digester 9 and 10 area. Q44: On drawing 1021‐2013‐12‐13 M1 ‐ please provide drawing for the distance showing the location from FIT 7623 to the location of panel LP‐B.  A44: Panel LP-B is located on the East wall of the Gas Compressor Building Electrical Room at ground level. The approximate distance to Panel LP-B is 70 meters. Q45: Dwg. No, S1, 102101213-12-11 suggest to see DWG. S3 which was not added to drawings. A45: The 'DWG S3' references in light grey font are as built drawing notes from the original Digester 7 and 8 construction period. Drawings S1 and S2 illustrate the scope of work for concrete repairs as identified in dark font and by the Repair Schedule numbers 1 to 9. Drawings S1 and S2 are to be read in conjunction with Specification 03925. Q46: Dwg. No. S2, 1021-2013-12-12 indicates amount '300' added for repair. Please define amount of '300'. A46: Text in light grey font are as built drawing notes from the original Digester 7 and 8 construction period. Drawings S1 and S2 illustrate the scope of work for concrete repairs as identified in dark font and by the Repair Schedule numbers 1 to 9. Drawings S1 and S2 are to be read in conjunction with Specification 03925. Q47: The contract and drawings specify replacement of the existing digester gas plug valves ( Neo ) with Velan full port ball valves. The laying length of these valves is significantly longer than the existing plug valves. In some areas we will not have the space to install these valves without significant piping modifications. The Velan regular port ball valves are the same laying length as the existing valves. Please review and advise if the regular port valves are acceptable. If regular port valves cannot be used we will require additional details for the piping modifications required .

A47: The specifications and drawings call for full port velan ball valves and are the same lay length as the existing long pattern plug valves on site. Any valve that does not have the same lay length as the Velan valve, a Bray Series 41 CGA DG valve with a make-up spool piece can be utilized. Q48: Are those digesters to be considered as confined space? A48: Yes. Q49: On drawing M15 shows new 300x300 louver and new doors and hardware, please provide specification. A49: See Q15 / A15.

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Q50: The pipe support as per M16, is there any dowel needed for the concrete foundation? And where those foundations sit on? A50: The foundations will be situated on compacted gravel and will butt up against the asphalt paving. Dowels are not required. Q51: Will those digester tanks float once we empty tanks? Are you going to provide the soil report to indicate the existing water level? A51: The digester tanks will not float when empty. A soil report indicating existing water level is not available. Q52: Drawing 1021-2013-12-27 - M15, Detail 4 - Please clarify the following questions with respect to this detail. Do the tees, nipples and ball valves on the orifice flanges have to be replaced? Is the entire differential pressure gauge assembly, mounting bracket, hoses, pipe fittings, U-bolts, etc. Re-installed? A52: The existing pressure gauge assembly is not re-installed, only the existing orifice flange needs to be re-installed. Install gauge and connection as shown on detail. Q53: Drawing 1021-2013-12-18 - M6 - Process Valve Schedule outlines 10 - 150 mm Knife gate valves identified as "N/A" - Type 4 Installation. Are these valve operators to be Chain wheel operated or Hand wheel operated? There are no Tag No's. or cross-sectional views to establish their heights from the operating floor level. A53: The 10 new knife gate valves require only hand wheel operators. Q54: Drawing 1021-2013-12-18 - M6 - Process Valve Schedule outlines 10 - 75 mm Sludge Sampling Valves with new Actuators, 5 for each Digester. Specification Section 015204 - Item 2.2 - Outlines 5 sampling valves which are 40 mm x 25 mm for each Digester. Drawing M6 only indicates 10 new sampling valves. Are there 20 new sampling valves required for this project? Please clarify. A54: Only 10 new sampling valves are required as per Drawing M6. No sampling valves as per 15204 are required. Q55: Could you please provide the name of the base building Controls Contractor A55: City approved SCADA integrators are listed in Addendum #2. Q56: Could another site meeting be arranged with a specialized trade for an ocular inspection of the area where vacuum excavation is required – Gallery No. 3 Leak Repairs. A56: An additional site meeting will not be arranged. Q57: Confirm the electrical scope of work required associated with the valve replacement works, specifically the removal and replacement of valve actuators. A57: Some of the electrical works are identified on the mechanical drawings. Refer to mechanical drawings and associated notes, including M1, M2, M5 and M6. Re-commissioning limit switches and valve operation following completion of the field wiring to be considered part of the required scope of work.

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Q58: In Addendum #4, Electrical Work Summary, item “c”, please provide manufacture and catalogue number for the new 100a, 208v, 3 pole breaker in distribution panel DP-A-9. A58: Existing panel was manufactured by Eaton Cutler-Hammer, Type PL-1, Job No. 24B358000. Coordinate with manufacturer to provide breaker suitable for installation inside of existing panel. Q59: Please clarify if the conduit for the new trailer is 2” PVC (as per drawing 1021-2013-12-86 ) or 41mm (1 ½” PVC? ) as per Addendum #4, Electrical Work Summary, item “c”. Also please clarify if this conduit is PVC schedule 40. A59: 50mm PVC Schedule 40 conduit. Q60: Section 15200 Clause 2.5 . Please provide the pipe specification for the 50mm Digester Gas Pipe on the roof and within the digester. ( is this pipe to be SCH 10s or SCH 40) Please provide this information for all small diameter SS Digester Gas Piping. A60: Per Specification 15200, digester gas pipe on the roof and within the digester will be Schedule 10S. Q61: Valve Schedules on Drawing M1 and M2 list the same Valve Tag #s but show different sizes for THR-DIG-V-7662, 7700, 7701, 7702 . Please clarify that these are the same valves and confirm the valve size. A61: Tags on M2 are correct. On drawing M-1, 4- 300 mm digester gas plug valve shall be supplied, tags to be field determined. Q62: Drawing M5. Please identify approximate location for Tie-in point for 40mm Flushing Water A62: The tie in point for the new 40 mm dia flushing water will be at floor level at the sink. Contractor shall connect new water line to existing via di-electric coupling. Q63: Drawing M16 . Please clarify whether all Unistrut, bases, hardware, pipe clamps etc are to be SS 316 . A63: Correct. Q64: Addendum 2. Drawing M 18/19 Please provide sizing for compressed air piping and approximate Tie – in location. A64: The elevation for the tie in is given in the addendum. Tie in location is underneath the foam scrubber buildings, some minor offset of the piping will be required – Contractor to field route piping. Piping into foam scrubber buildings shall be 15 mm (1/2 inch) diameter. Q65: In Addendum #2, Electrical Work Summary, item “j”, “Modify gas booster starters, overloads and control circuitry in MCC...” - please provide detailed scope of work and drawings. A65: Refer to drawing E11 for wiring block diagram and additional details. The intent of the statement is for the control circuitry for the starters and overloads to be modified as necessary to provide signals for SCADA monitoring. Refer to Sketch 1 and 2 attached to this Addendum #5.

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The following I/O is described in the addendum, but not shown on the drawings. These details shall be incorporated into the noted drawings. THR-PRM-RPU-0010 (Drawing E47) Rack 2, Slot 3, Input 9: THR-ACC-xxx-xxxx** [DX558] Boiler BO-0800 Gas Booster Running Status Rack 2, Slot 3, Input 10: THR-ACC-xxx-xxxx** [DX558] Boiler BO-0800 Gas Booster Fault Status ** Gas booster tag to be finalized post-tender. THR-PRM-RPU-0011 (Drawing E52) Rack 1, Slot 6, Input 9: THR-ACC-xxx-xxxx** [DX557] Boiler BO-0900 Gas Booster Running Status Rack 1, Slot 6, Input 10: THR-ACC-xxx-xxxx** [DX557] Boiler BO-0900 Gas Booster Fault Status ** Gas booster tag to be finalized post-tender. Q66: Do we need to flush any of the sewage lines? If yes, please provide the measurement for this. A66: Refer to Drawing M-7 and Specification 02228. Q67: Drawing M1 Note states that all recirculation and compressor isolation valves to have Pneumatic Actuators except V-5860D and V- 5660D. Schedule shows 12" isolation valve V-5822 and V-5820 with actuators. Please confirm if these valves are to have Pneumatic Actuators. A67: Valve 5860D and 5660D do not require pneumatic actuators, these valves can be manual valves. Q68: Drawing M6 - Note 5 - States that existing solenoids and regulators to be replaced contractor to disconnect and reconnect existing as required. Please confirm that these solenoids refer to Pneumatic Actuator Controls detail shown on drawing E2? Is an individual regulator assembly required for each Knife Gate Valve? A68: An individual regulator and solenoid is required for each valve. These solenoids refer to drawing E2. Q69: Drawing M-18 indicates new pneumatic actuators to be installed for existing ball valves. Please indicate if these valves also require individual regulator assemblies and solenoid valves for each valve? A69: This is correct. Q70: Addendum 2 calls for supply and install of new instrument airline. Please confirm the size of the airline as it is not mentioned. A70: Instrument airline shall be 12 mm (1/2”). Q71: We'll need some more clarification on whether or not the $2mm Contractor's Pollution Liability (CPL) is mandatory. The reason being that the first sentence of the clause states "Where specified in the Contract Documents, the Contractor shall provide." however the Contract Documents (CCDC 2-2008) do not specify anything regarding CPL coverage. A71: Section 5A, Specific Conditions of Contract, Paragraph 26.4 - Insurance (Page 5A-21) indicates that the Contractor's Pollution Insurance is not required.

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Should you have any questions regarding this addendum contact Allison Philips at 416-397-4825 or by email at: aphilli2@toronto.ca. Please attach this addendum to your RFT document and be governed accordingly. Tenderers are to acknowledge receipt of all addenda in their Tender in the space provided on the Tender Cover Page as per Section 1 – Tender Process Terms and Conditions, item 8 of the RFT document. All other aspects of the RFT remain the same. Victor Tryl, P. Eng Manager Professional Services

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DIGESTER 9 AND 10 REHABILITATION - ADDENDUM #5

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Digesters 9 and 10 Rehabilitation - Addendum #5 - Reference: Question/Answer #65 Sketch 1

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Digesters 9 and 10 Rehabilitation - Addendum #5 - Reference: Question/Answer #65 Sketch 2

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