FLORIDA GOVERNMENTAL UTILITY AUTHORITY (FGUA)

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1 FLORIDA GOVERNMENTAL UTILITY AUTHORITY (FGUA) BID NO. GG P07; Rehabilitation of Treatment Unit No. 1, Golden Gate Wastewater Treatment Plant in the Golden Gate Utility System A. SCOPE Addendum No. 1 September 26, 2016 This addendum is hereby incorporated into the bid documents of the project referenced above. The following items are clarifications, corrections, additions, deletions and/or revisions to and shall take precedence over the original documents. Additions shall be shown as underlined and deletions shall be shown as strikethrough. Addendum 1 only includes clarifications that were brought up at the Pre-Bid Meeting B. BIDDING INSTRUCTIONS 1. Pictures a. Over 250 pictures of the project have been posted on TKW s FTP site. To log into this site Page 1. ftp://mail.tkwonline.com/ Username: envieng password: envieng 2. Reports a. A Copy of TKW s Tech Memo and the Ultra Sonic Testing Report from the original inspections are attached to this Addendum.. 3. Walk Throughs a. Walkthroughs maybe scheduled through FGUA. 4. Permit a. FGUA will provide copy of operating permit if requested. 5. Engineer s Estimate of Probable Construction Cost a. The engineers estimate of probable cost is $1,154, Contact a. The proper contact address for Rob Dickson of FGUA is rdickson@govmserv.com. This was listed incorrectly in the meeting minutes. 7. Notice to Proceed a. The anticipated date for notice to proceed is January 4, The tank will be available to the Contractor on this date. C. BIDDING FORMS Addendum No. 1 September 26, 2016 Page 1 of 2

2 1. Section Legal Ad a. Page , in the third paragraph REPLACE September 8 with September 15. b. Page , in the second to last paragraph REPLACE 60 calendar days with 120 calendar days. 2. Section Instructions to Bidder a. Page , ARTICLE 11 CONTRACT TIMES, 11.01, REPLACE 60 calendar days with 120 calendar days. 3. Section BID FORM a. REPLACE the existing Bid Form page with a new Bid Form page which is attached to this Addendum No. 1. An allowance for the electrical portion of the project has been added as well as the Owner s Contingency Allowance has been established. The Measurement and Payment will be revised in Addendum 2 to match this. b. In ARTICLE 7 ATTACHMENTS TO THIS BID, Item E, the Affidavit for Trench and Safety Act, will not be required. D. CONTRACTING FORMS 1. Section AGREEMENT a. Page , 4.03 Liquidated Damages, REPLACE the sentence: $250 with $1000. E. SPECIFICATIONS 1. Section MEASUREMENT AND PAYMENT a. Page 3. Item 7. REPLACE the entire description of the Measurement and Payment of the Launder with the following: Launder Repair/Replacement: The lump sum amount shall include the furnishing of all materials, labor, equipment, and services to be paid for the repair or replacement of the launder as depicted by the two options on the drawings. Option 1 is repair the launder including to sand blast, patch, and line the existing launder. Option 1 would include cutting and patching the ¼ launder outside wall plate as necessary, cutting and patching the ¼ bottom plate as necessary, the replacement of any failing portions of the ¼ top of the clarifier wall that is part of the launder, the replacement of the launder brackets as indicated on the drawings and also any surface prep and coating. Option 2 is to replace the launder in its entirety with a prefabricated launder including all the items listed above including replacing the top 12 of the clarifier wall. (See sheet S 201, reference numbers 3, 4, 5, 18, 20, 27). b. Page 3. Item 13. REPLACE the words lump sum with allowance. END OF SECTION Addendum No. 1 September 26, 2016 Page 2 of 2

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4 TECHNICAL MEMORANDUM Golden Gate Wastewater Treatment Plant Rehabilitation Treatment Unit 1 Facility identification # FLA In Collier County January 19, 2016 Prepared for: Florida Governmental Utility Authority (FGUA) Prepared by: TKW CONSULTING ENGINEERS, INC 5261 Banner Drive Fort Myers, FL (239) Certificate of Authorization No. 5762

5 Background The purpose of this Technical Memorandum is to present the results of the structural and electrical inspections of the one-million-gallon treatment tank at the Golden Gate Wastewater Treatment Plant (WWTP) located in Collier County. The Facility is owned by the Florida Governmental Utility Authority (FGUA). This existing steel structure has been deteriorating over the years and the Florida Department of Environmental Protection (FDEP) has issued an Administrative Order requiring that these issues be addressed. The Administrative Order requires that FGUA conduct inspections to the structure and determine the areas that require repair and that these repairs then be completed. TKW Consulting Engineers, Inc. (TKW) was issued a work order by the FGUA to perform the inspections required by FDEP. The inspections included four separate inspections. The first was to do a structural inspection of the outside of the tank and also the inside of the tank above the water line. This inspection was completed on October 07, FGUA then had the tank drained and cleaned so the next three inspections could occur. These included a structural inspection of the portion of the tank that was previously under water, an electrical inspection of the cable, conduit, junction boxes, and control panel enclosures, and ultrasonic thickness measurements of the steel tank to determine section losses. The structural inspection was completed on December 14 th and 17 th, The electrical inspection was completed on December 14, 2015, and the ultrasonic thickness testing was completed on December 30, 2015.The results of the inspections are presented in this Technical Memorandum. Structural Inspections Tank Wall Exterior Observations: The exterior of the tank wall is in very good condition. There are areas of minor paint/coating defects that are in need of maintenance. Several locations around the tanks exterior, electrical conduit brackets have been welded to the exterior of the tank wall and have rusted and could affect the tanks structural integrity. Multiple light pole attachment brackets and steel support connections have rusted through and are in need of repair or replacement. The supports for the steel catwalk at the top perimeter of the tank are in need of repair or replacement. There are multiple areas of problematic rusted connections that require attention. A steel channel at the top of the tank wall and helps the catwalk support frames, is in need of maintenance and repair. Multiple pipe support brackets are in need of maintenance and repair. Welds for the brackets are rusted. Several of the pipe bearing plates require maintenance or replacement. Pipes in several locations require maintenance and repair. The exterior access stair is in good condition. General maintenance is required for the painted surfaces. There are a few rusted areas that required maintenance at the stair handrail support brackets. The stair platform steel columns and bearing plates require maintenance and repair. In multiple locations the stair platform grating attachment clips are loose or missing. TKW CONSULTING ENGINEERS, INC. Technical Memorandum on Golden Gate WWTP Inspections January 2016 Page 2

6 Tank Wall Interior Observations: The interior of the tank wall is in very good condition. The tank wall coatings are peeling and flaking off of the interior wall and require maintenance and replacement. The tank wall has a continuous ring of surface rust at the high water mark. The coating has worn off at water line and caused a rust ring, maintenance is required and replacement of the tank coating. Interior hydrostatic and non-hydrostatic steel walls are in very good condition. Wall coatings are peeling and flaking off of the wall and require maintenance and replacement. There are multiple hydrostatic and non-hydrostatic wall braces throughout the plant. The bases at many of these wall braces have moved causing the hydrostatic and non-hydrostatic walls to bow and in some locations buckle the base plates. Improper attachment of the base to the concrete slab is the probable cause. The brace base anchorage consists of rebar protruding from the slab then bent over the steel brace base plate. Installation of proper base plate anchors is required, and replacement of multiple brace base plates. Many of the welds along the hydrostatic and non-hydrostatic wall rib supports are rusted and require maintenance and possible re-welding. Several of the rib supports have rusted through and require replacement. The coatings have been worn off and require maintenance and replacement. The chlorine contact tank walls are in fair condition. The baffles inside of the contact tank have buckled and are in need of repair/replacement. There are multiple locations within the chlorine contact tank surface that have rusted and require maintenance of the wall surface. The top baffle support angles and the vertical support stiffeners are rusted and buckled and require replacement. Concrete Slab Tank Base: The sacrificial sloped grout slab in the Clarifier is in pour condition. The surface is eroded, pitted, worn and scarred. The coatings have eroded away or are peeling. In some locations there are living organisms living between a layer of coating and the eroded grout surface. The scraper mechanism has worn the surface of the grout in multiple locations. Grout aggregate is exposed in most of the grout surface. Re-surfacing of the grout bed is required, and a new application of concrete coatings is required. The scraper mechanism is in very good condition. General maintenance is required and new coatings applied. Within the separate chambers (influent, aeration, anoxic zone, re-aeration and sludge holding) the concrete slab surface is in fair condition. Many locations there are surfaces that have erosion issues. Areas of deep pitting in the floor were observed, required patching of the concrete slab. Coatings in the chambers have worn and eroded away requiring new coatings to be applied. Above Water Equipment and Catwalk: The catwalk steel around the perimeter of the tank wall, at the mixer access locations and the chlorine contact tank are in fair condition. Multiple catwalk supports are in need of maintenance and repair. Several of the supports require replacement. The catwalk steel that spans across the tank is in fair condition. The catwalk end support steel requires replacement. The steel for these supports are rusted through and have major section loss. The two steel beams that support the catwalk, and skimmer arm mechanism are in need of maintenance and repair. The bottom beam flanges have some section loss but can be repaired. Many of the steel bracing between the two steel beams are rusted through and required replacement. TKW CONSULTING ENGINEERS, INC. Technical Memorandum on Golden Gate WWTP Inspections January 2016 Page 3

7 The catwalk grating is in very good condition. Many grating attachment locations are loose or missing and require maintenance or repair. The catwalk guardrail is in good condition. Some of the guardrail ends, intersections, corners and attachments do not meet current OSHA requirements. Many toe plates are missing. Some of the toe plate attachment welds are broken. Many of the guardrail post connections are in poor condition. Post u-bolts are rusted and in need of repair or replacement. Post connection plates are rusted and in need of repair or replacement. The stilling well is in good condition. Surface rust was observed on the steel plating of the stilling well, requiring maintenance. Coatings on the stilling well are in need of replacement. The stilling well bracing is in good condition. Minor rust was observed; coatings are in need of replacement. The clear clarifier launder is in poor condition and will require replacement. Several locations the rust in the launder has eroded through the trough wall. Brackets and supports for the launder are in poor condition and required replacement. Attached to the launder trough are the aluminum weir and a steel scum baffle. The aluminum weir plates have been eroded and in many locations are missing. Replacement of the weir plates is required. The steel scum baffle plates are rusted and eroded at the weld connections. Replacement of the scum baffle plates is required. The skimmer arm is in good condition. Surface rust was observed maintenance. The coatings on the arm are in need of replacement. The return waste sludge splitter box is in poor condition. There is a splash deflector shield that is attached to the splitter box with c-clamps. This entire splitter box and deflector requires replacement and proper attachment. Electrical Inspections Lightning Protection: No lightning protection was observed on either the circular steel plant structure nor the pole mounted light fixtures. RKS observed grounding to the circular steel plant around the perimeter of the structure. No visible ground rod test wells were observed around the plant structure. FGUA plant personnel advised of ongoing upgrades under a separate project to the circular steel plant for lightning protection and bonding & grounding. Personnel indicated a ground grid has been installed around the perimeter of the tank along with ground rods. Lightning Protection: Rigid PVC, flexible PVC and Rigid metallic conduit materials were utilized throughout the circular steel plant installation. RKS noted circular catwalk widths along the circular steel plant were 2 throughout the installation. The central catwalk was 3 wide. The condition of the conduit varied throughout. RKS noted several areas of concern with respect to conduit condition and location. Flexible conduit was observed routed above the catwalk on the Eastern end of the steel plant, adjacent to the booster pump disconnect. The conduit run was noted as a potential trip hazard. TKW CONSULTING ENGINEERS, INC. Technical Memorandum on Golden Gate WWTP Inspections January 2016 Page 4

8 RKS observed a damaged conduit body at grade level on the Southwestern perimeter of the steel plant. The damaged conduit body caused exposure of several insulated conductors. The conductors originate from the clarifier drive junction box. The conduit containing the exposed conductors routed parallel to the central catwalk and transitions to a vertical drop at the end Southwest end of the tank into the damaged conduit body. RKS noted the parallel routing of the conduit along the cat walk contains no supports and utilizes the construction of the catwalks as a supporting means. At the Anoxic Mixer #2 equipment a broken conduit was noted. The conduit was not in compliance with the NEC 2011 minimum support intervals. FGUA staff advised that the equipment was not utilized and considered unnecessary for the treatment process. There was a damaged rigid metallic conduit body below the Zone 4&6 Dissolved oxygen analyzer instrumentation enclosure. Along the Eastern perimeter of the steel plant, an abandoned conduit and conduit body was observed at graded level. The conduit was uncapped and contain no means of preventing water intrusion. Booster Pump Equipment: The booster pump electrical equipment installation consists of a rail mounted non-fused, 600Vac, 30 Amp NEMA 3R disconnect switch and a 1HP 115/230V single phase booster pump. The equipment is located on the Eastern intersection of the innermost circular walkway and central walkway. The pump is fed from panelboard 1L1 located in the electric room, South of the circular steel plant. Corrosion was noted along the disconnect enclosure bottom and door. Surface oxidation was noted on the switch blades, feeder lugs and ground lug. No duct seal was installed in the conduit. The location of the pump disconnect is not in compliance with the NEC requirement for equipment working space. The minimum working space in front of the equipment as required by code is 3 for 0-150V and 3-6 for 151V-600V. RKS noted that the Booster pump is currently fed from a 208/120V panel. FGUA personnel indicated that the pump is wired to run on 208V. RKS observed an alarm panel rail mounted directly above the booster pump. FGUA personnel indicated that the alarm panel is out of service and not being utilized. Clarifier #1 Drive: The clarifier drive electrical installation consists of a handrail rail mounted PVC junction box, an unmarked control switch in a fiberglass enclosure and a 1/2HP 480V-3PH drive. The drive is located at the center of the central walkway. The clarifier drive equipment breaker is located in the electrical room, South of the circular steel plant. The junction box contained wiring for connection between the hand-rail mounted unmarked switch and pump feeders. Damage to the clear outer jacket of the insulation was noted. The conductors appeared in fair condition. Electrical connections within the junction box were achieved via wiring nuts. No duct seal was installed in the conduit. An enclosure containing terminations for the overload torque switch was observed on the East catwalk interconnecting clarifier 1 to the influent structure. The panel contained 120V equipment, a power supply and several wire nut connections. TKW CONSULTING ENGINEERS, INC. Technical Memorandum on Golden Gate WWTP Inspections January 2016 Page 5

9 In the electrical room a Siemens motor control center houses the clarifier drive 2 Amp breakers and starter. The breaker buckets appeared in good condition. No signs of arcing, corrosion or other contaminants were noted in the breaker bucket. RKS noted adequate equipment working space in front of the 480V Motor Control Center (MCC). Dissolved Oxygen Analyzers: The analyzer enclosures were observed in good condition. Zone 2 analyzer is located on the North side of the central circular catwalk. Zone 4 & 6 analyzers were located on the Southwestern end of the central circular catwalk. No corrosion was noted on the equipment terminations, ground bus bar or DIN Rails internal to the NEMA 4X PVC enclosure. All conduits entering the enclosure were duct sealed. Ditek 120V surge suppression & analog signal loop protection was installed in each enclosure. Anoxic Mixers 1&2: The anoxic mixers electrical installation consists of (2) sets of 480V-3PH mixers, HOR switches in fiberglass enclosures, forward-off-reverse switches (FOR) and PVC junction boxes. Anoxic mixer 1 equipment is located on the West end of the steel plant and anoxic mixer 2 equipment on the Southwest end. Based on the location of the (2) sets of mixer equipment, the switch enclosures and junction boxes are not in compliance with the NEC 2011 working space clearances. FGUA personnel indicated that the equipment was not utilized and unnecessary for the current treatment process. The branch circuit breakers feeding the Anoxic Mixer equipment were located in the electrical room, south of the circular steel plant. A Square D Model 6 motor control center houses the anoxic mixer 30Amp breakers and starters. The breaker buckets appear in good condition. No signs of arcing or corrosion were noted on the breaker equipment. RKS noted adequate equipment working space in front of the Motor Control Center (MCC). Mixers 1-3 & Level Switches: The Mixers electrical equipment installation consists of handrail mounted NEMA 4x stainless steel disconnects and mixer. A level switch with a handrail mounted NEMA 4x stainless termination cabinet is installed at each mixer station. The mixer stations are located on the Northwest, South and East ends of the circular steel plant. The disconnect switches were in fair condition. Light oxidation was observed in the interior of the Drive No.1, 2 & 3 disconnect enclosure, line/load side lugs and grounds. No duct seal was observed in the conduit. The Level switch termination cabinets were in fair condition. The cabinets exhibited light oxidation on the back panel, mounting hardware, ground bars and conduit hubs. Termination blocks showed no oxidation. Conductors appeared in good condition. No duct seal was installed in the conduit. FGUA personnel advised that the mixers were not utilized and unnecessary for the current treatment process. The current location of the Clarifier mixer disconnects do not comply with the 2011 NEC working space requirements. TKW CONSULTING ENGINEERS, INC. Technical Memorandum on Golden Gate WWTP Inspections January 2016 Page 6

10 Mix drive No.3: Mixer Drive No.3 electrical equipment consisted of an HOR switch, FOR switch and disconnect switch. The disconnect switch is in poor condition. Oxidation on the line/load lugs, grounds, switching blades and mechanism is evident. FGUA personnel advised that the equipment was not utilized and unnecessary for the current treatment process. The current location of the Mixer Drive disconnect does not comply with the 2011 NEC working space requirements. Level Instrument: The level instrument electrical equipment installation consists of a handrail mounted PVC enclosure containing the effluent flow level transmitter. The enclosure is located on the South end of the circular steel plant. The enclosure was in fair condition and no corrosion was observed on the hardware or back panel. Flexible conduit connections to the enclosure were in poor condition. (1) flexible conduit observed was broken below the enclosure. An additional broken conduit fitting was observed on the right side of the enclosure. No duct seal was installed in the conduit. No Analog or 120V surge suppression was observed in the enclosure. Level Instrument: A uni-strut rack mounted NEMA 4x stainless steel instrumentation termination cabinet was observed on the South end of the circular steel plant. The termination cabinet contained the level switch control wiring for the LSL-100, 101 &102. The termination strips, ground lugs and mounting hardware were in good condition. No duct seal was installed in the conduit. The enclosure is in compliance with the NEC 2011 working clearance requirements. General Observations: At grade level on the East end of the circular steel plant, RKS observed (2) PVC enclosures containing electrical wiring. The northernmost enclosure appeared to be a junction box for 120V site lighting and a 480V feed to the Bar screen. The site lighting junction box was observed to be in fair condition. Electrical connections in this enclosure were achieved using wiring nuts. The pull box enclosure to the south was in poor condition and appeared to contain instrumentation cable. The pull box cover was broken and being secured with only electrical tape. Ultrasonic Thickness Inspections Tank Inner Wall: Ultrasonic thickness readings were taken to determine the remaining thickness values of the inner tank walls. Fifteen readings of the inner tank wall were taken incrementally 360 in a clockwise pattern around the tank at the high water line. At or near the areas inspected the surface coatings are spalled and peeling with bare metal exposure to the atmosphere. The inner tank wall readings varied from the thinnest reading of.250 to the thickest reading of.263. All tank wall readings are within normal thickness. Localized surface corrosion and pitting is evident throughout the launder trough area and the attached structures. Multiple readings were recorded at these areas, the thinnest recorded at.196. As stated above in the Structural Inspection, the launder trough requires replacement. TKW CONSULTING ENGINEERS, INC. Technical Memorandum on Golden Gate WWTP Inspections January 2016 Page 7

11 Tank Outer Wall: Ultrasonic thickness readings were taken to determine the remaining thickness values of the outer tank walls. Fifteen readings of the outer tank wall were taken incrementally 360 in a clockwise pattern around the tank at the high water line. At or near the areas inspected the surface coatings are spalled and peeling with bare metal exposure to the atmosphere. The outer tank wall readings varied from the thinnest reading of.247 to the thickest reading of.263. All tank wall readings are within normal thickness. TKW CONSULTING ENGINEERS, INC. Technical Memorandum on Golden Gate WWTP Inspections January 2016 Page 8

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