2024 Design and Construction Standards - Section 5 - Wastewater Pumping Stations

10 SECTION 5 – WASTEWATER PUMP STATIONS 1 Design 11 Description of Work A Work under this section consists of furnishing and installing submersible pump stations as detailed on the plans and specified herein It shall include all labor , materials , site grading , structures , excavation , sheeting , backfill , reinforced concrete , masonry , carpentry , yard piping , equipment piping , miscellaneous piping , equipment , electrical work , controls , incidental painting , and all other items or material and work required to construct structures and furnish and install equipment for a complete installation as hereinafter specified B If the project is funded by a private developer , the developer is responsible for coordinating with the power provider to install 3 phase power to the wastewater pump station In addition , the developer shall be responsible for any costs associated with providing power to the wastewater pump station The developer will be responsible for the monthly power bill until the County accepts the wastewater pump station It shall be the developer’s responsibility to contact the County and request the power billing account is transferred to the Department of Utilities 12 General A Wastewater pump stations shall be designed and permitted at a minimum in accordance with 15A NCAC 2T Regulations , 15A NCAC 2T Regulations , Section 0300 – Sewer Extensions B Prior to construction of the facilities , the Contractor shall be responsible for obtaining an electrical permit from the Johnston County Building Inspections Department for all work associated with the project C Obtain pump station site plan approval from the planning department , if required D Various items or work and materials to be provided under this section are covered under other sections of these specifications 13 Pump Station Site A Access Road 1 The pump station access road shall be a minimum 10 - feet wide , and shall consist of 8 - inches CABC and 2 - inches asphalt 2 The access road shall have a maximum longitudinal slope of 10 and maximum cross slope of 4 3 An asphalt vehicular turn around triple axel should be provided outside of the fence Turn around shall be designed to accommodate a 25ft long truck B Easements 1 Either easements or a standalone lot may be recorded for the pump station 2 A minimum 20 ’ wide public utility easement will be required to access the pump station 3 A minimum of 5 ’ will be required between the fence and the recorded easement C Fence 1 Pump station site shall be enclosed by 6 - feet high chain link fence as described in standard sewer details Section 5 - 1 WASTEWATER PUMP STATIONS 2024 RevisionPageSECTION 5 – WASTEWATER PUMP STATIONS 2 A minimum site area of 50 - feet x 50 - feet shall be inside the fence D The site shall be laid to accommodate an odor corrosion control system with chemical storage tank and containment Storage area shall be within 30 - feet of the turn around outside of the fence 1 The County reserves the right to require corrosion control on pump stations 120 GPM or larger 2 Any pump station 500 ’ from a residential lot or school must have a carbon filter E All areas inside the site fencing shall be treated with herbicide , landscaping fabric , and 4 - inches depth of # 57 stone F Wet well 1 Shall be accessible on at least one side by service truck with crane mounted on rear passenger side 2 Shall not be located within 50 - feet of wetlands G Positive drainage away from all structures shall be provided H Control panel shall be within sight distance of wet well and panel shall be facing wet well I Valve vaults , meter vaults , and the RPZ ‘ Hot - Box ’ shall have electrical outlets installed in each J A bypass connection shall be installed for all sites See standard detail K The site must be landscaped to meet all County requirements L Gates 1 Pump stations with pumps less than 60 HP shall have gates min 12 - feet wide double door or sliding gate with chain and pad lock 2 Pump stations with pumps 60 HP or greater shall have gates a minimum of 14 - feet wide double door or sliding gate with chain and pad lock M Potable water shall be provided via a yard hydrant with RPZ at connection to the water main 14 Submittals A All submittals , construction drawings , specifications , and “ as - built ” drawings shall meet the minimum criteria in Section 8 - Certification , Submittals , and Inspections B Shop drawings and manufacturer’s data shall be submitted to the Engineer and the County for the following items 1 Pumps 8 Rain hood 2 Wet well 9 Valve Vault 3 Generator ATS 10 Coatings 4 Drives 11 Basket Screen 5 Valves 12 Stationary Davit Crane 6 Meter 13 In - channel Grinder 7 Controls 14 Manholes Section 5 - 2 WASTEWATER PUMP STATIONS 2024 RevisionPageSECTION 5 – WASTEWATER PUMP STATIONS 15 Geotechnical Report for wet greater than 20 ’ in depth well location and any manhole C Certificates of Compliance shall be submitted to the Engineer and County for the following 1 Pumps 2 Drives 3 Controls 4 In - Channel Grinder all stations 200 GPM or greater D Equipment manufacturers shall furnish six 6 copies of an operating and service manual covering their equipment The manual shall contain complete descriptions of each item of equipment and a complete parts list showing factory parts numbers It shall also contain complete operating and service instructions and shall be tabbed and indexed for easy use Manuals shall be submitted within 60 days after final approval of shop drawings 2 Materials 21 General A The contractor shall furnish , take possession of when delivered , and install the following equipment where shown on the Plans , complete with all incidental and appurtenances required for a complete , finished installation All equipment components shall be adequately sized to carry all loads and stresses occurring during fabrication and erection and resulting from normal and emergency operation in the installation shown on the Plans and under the conditions specified and or implied 22 Submersible Pumps A Pumps 1 Pumps , motors , and controls shall be as specified herein and as indicated on the plans a Type Vertical submersible centrifugal non - clog , 2 required b Capacity ____ gpm @ _____ ft TDH c Minimum sphere size 3 - inch d Efficiency at design point ____ min e NPSHr at design point ____ ft max f Motor performance requirements i Maximum motor horsepower ____ hp ii Maximum motor speed 1800 rpm iii Nominal power supply 480 VAC , 3 phase , 60 Hz iv Maximum current ____FLA , ____ LRA v Minimum power factor at full load _____ vi Minimum efficiency at full load ____ Section 5 - 3 WASTEWATER PUMP STATIONS 2024 RevisionPageSECTION 5 – WASTEWATER PUMP STATIONS vii Minimum service factor 115 2 Pumps shall be submersible , centrifugal non - clog capable of passing solids as specified with hydraulic sealing diaphragms , pump mounting plates and base elbows with bottom rail supports , stainless steel upper rail supports , stainless steel lifting cable , schedule 40 - A stainless steel guide rails , and stainless steel cable supports 3 Pump housing shall be of heavy cast iron construction 4 All fasteners shall be 303 stainless steel or approved equal 5 Each pump shall be capable of being hoisted vertically out of the wetwell , and returned to operation without requiring the operator to enter the wet well 6 It is the intent of these specifications that the pumps , base plates , guide rails , hoisting cable and connections to the control system including panel , starters and circuit breakers , be provided by the pump manufacturer as an integral system 7 The impeller shall be of bronze , ductile iron , or other durable , corrosion - resistant approved material 8 The pump impeller shall be of semi - open non - clog design and shall have back vane s to prevent buildup of solids behind the impeller 9 The impeller shall be rigidly fixed to the motor shaft with a key s or other approved fastener so designed to prevent separation under rotational loading 10 The motor shaft shall be stainless steel , supported by upper and lower bearings 11 The upper bearing shall be a self - lubricating ball bearing 12 The lower bearing shall be a sleeve bearing or double row ball bearing lubricated from an oil chamber 13 Shaft and bearing shall have sufficient section to withstand all rotational and axial loading to be reasonably expected under normal wastewater pumping situations 14 The shaft shall be sealed from the volute with an oil - lubricated mechanical seal system The oil chamber shall be equipped with a seal sensor system to detect any leakage around the seal system 15 Lower pump seals shall be tungsten carbide , double type One replacement seal for each pump must be submitted to the County 16 The motor chamber shall be suitably sealed from the other chambers of the pump and from the exterior so as to be entirely suitable for submerged operation The motor chamber may either be of oil - filled or air - filled design 17 Pumps shall be as manufactured by Ebara , Fairbanks Morse , Flyght , or Wilo - EMU or approved equal 18 All pumps 125HP and larger shall be equipped with VFD , housed in approved prefabricated climate controlled electrical building Section 5A of the Johnston County Public Utilities Specifications outlines the requirements for VFD applications B Motors 1 Pump motors shall be of the sealed submersible type meeting UL Class I , Group D , Division I - Explosion proof requirements The maximum rpm of the motor shall be 1200 , Section 5 - 4 WASTEWATER PUMP STATIONS 2024 RevisionPagePage pageNumber5SECTION 5 – WASTEWATER PUMP STATIONS unless approved by the Utilities Department Motors shall meet NEMA thermal rating MGI - 1242 All leads are to be epoxy sealed 2 Motors rated 25HP up to 125HP will be equipped with a soft start All motors rated 125HP and greater will be equipped with a VFD Motors used on variable frequency drives VFDs shall be rated for inverter duty applications NEMA MGI - 31 a Reduced Voltage Soft Starters shall utilize input and output contactors Internal or External bypass contactors shall be utilized when output is at full voltage b Acceptable RVSS Manufacturers i Schneider Electric ii ABB iii Danfoss iv JCPU Approved Equal 3 Moisture sensing probes and thermal protectors shall be furnished 4 Motor frame and end shield shall be corrosion resistant cast iron 5 Insulation shall be compatible Class B rated system with Class F material rated for continuous duty in 40 - degree C liquids 6 Motor shaft shall be type 416 stainless steel 7 All hardware shall be stainless steel 8 Submersible pump motors shall be furnished by the pump manufacturer 9 Motors shall not be overloaded at any point within the operating range 10 Motors used in a VFD application are subject to additional requirements and must be pre - approved by the Department of Utilities Section 5A details the requirements for VFD applications 11 Motors shall be furnished with a minimum of 40 - feet of submersible , waterproof , and multi - conductor power and control cable The cables shall travel through an RGS conduit located on the vent rack to the control panel Cable size shall be sufficient to meet motor requirements C External Chamber Seals and Connections 1 The pumping chamber shall be sealed tightly together utilizing “ O ” - rings or resilient gasket material 2 The power cable connection shall provide for a positive clamping action to seal the electrical connection and relieve strain on the cable strands 23 Pump Controls A The pump manufacturer shall provide the pump control panel and accessory equipment B The contractor shall install the controls as shown on the drawings and manufacturer’s instructions C The control system shall include all motor starters , alternator , relay , level control switches , control panel , circuit breakers , alarm apparatus , and internal wiring Section 5 - 5 WASTEWATER PUMP STATIONS 2024 RevisionPagePage pageNumber6SECTION 5 – WASTEWATER PUMP STATIONS D For stations that are NOT equipped with Variable Flow Control , discrete cable supported displacement switches shall be employed for level control E For stations , WITH speed control such as a VFD AFD , the level control system shall consist of an approved 4 - 20mA pressure transducer with lightening surge protection integral to the transducer in either a submersible or an approved bubbler arrangement with duplex air compressors and manually adjustable set points F If the station has basins and a wet well , level control for the basin may be accomplished with the use of an Ultrasonic Level Transmitter with the Pump wet well having discrete cable supported displacement switches as a backup in case of failure G For any Station utilizing level control devices other than discrete cable supported displacement switches , then discrete cable supported displacement switches must be used for High Well Alarm and Low wet well cutout H Provided with the pump and control equipment shall be electrical contacts , an alarm light and alarm horn which shall be mounted on the exterior of the station The alarm equipment shall be interlocked with wetwell controls to be actuated upon high wet well levels or loss of phase The alarm circuits shall be 120 vac circuitries 24 Control Sequence A For stations that are NOT equipped with Variable Flow control devices such as a VFD AFD 1 On rising liquid in the wet well , a mercury - type float switch shall start the lead pump 2 As the liquid continues to rise a Second float will start the lag pump 3 The pump s will continue to pump until the liquid level recedes to the level of a third float switch that shall stop the pumps 4 If the level continues to rise above the “ lag ” float switch a fourth “ High Well ” float switch shall energize the alarm circuit B For stations equipped with Variable flow speed control devices such as VFD AFDs 1 A well - set point range will be utilized , when the liquid level rises the pump speed shall be increased proportionally to the level utilizing a standard PID loop 2 If the pump speed increases to maximum and liquid level is not decreasing then a second lag pump will start and both pumps will adjust together according to level conditions 3 If the liquid level recedes below set point range , the pump speed will be decreased proportionally to the level utilizing a standard PID loop , if 2 pumps are running then once the pumps decrease to a minimum speed setting the second lag pump will turn off If the liquid level continues to drop as the sole pump is running at minimum speed the pump will turn off until the liquid level rises above minimum set point C The pumps shall automatically alternate between the “ lead ” and “ lag ” positions by means of an electric alternator in the panel 25 Control Panel Section 5 - 6 WASTEWATER PUMP STATIONS 2024 RevisionPagePage pageNumber7SECTION 5 – WASTEWATER PUMP STATIONS A Lights , Switches , and buttons shall be of a standard 30mm waterproof style B Control Panel Indicator Lights 1 All indicator lights shall utilize LED technology instead of incandescent bulbs 2 Indicator lights will be labeled and provided for the following items as a minimum requirement a “ Pump Run ” Green - one for each pump as required indicating the pump is in the run condition b “ Seal Fail ” Amber - one provided for each submersible pump energized off the moisture detection sensor circuit c “ Over Temp ” Amber – one provided for each pump , energized off the overload or over temperature detection circuit for each pump d “ High Wet well ” Red – indication for the high wet well detection circuit e “ Low Wet well ” Red – indication for the low - level cutout float , if equipped f “ Loss of Phase ” Red – Indication for the Phase Monitoring Detection circuit , and shall indicate when abnormal power is present g “ RTU Controlled ” White – Indication for when telemetry unit is in control of station h For pumps requiring reduced voltage soft starters RVSS an additional “ RVSS Fault ” indicator red shall be provided i For pumps requiring variable frequency drives additional indicators shall be added including a “ Drive Fault ” red 3 All indicator lights shall be of a “ press to test ” type or as an alternative a single test button may be added to facilitate a test of all indicator lights C Control Panel Switches , Buttons and Interfaces 1 A 3 - position switch shall be used and labeled for each pump for “ Hand Off Auto ” operation “ Hand ” position shall operate the pumps regardless of liquid level indication “ Auto ” , will allow for normal site operation “ Off ” position will be a true off preventing any local or remote running of the pump 2 For stations requiring a VFD a speed adjusting potentiometer for each pump shall be added “ 0 - 100 ” and an additional “ Manual Auto ” Switch shall be added to provide the ability to run pump by manual speed operation utilizing the Speed Potentiometer “ Auto ” operation will use an automatic speed adjustment as described in section 24 3 A single 3 position “ Off On Test ” switch shall be provided that will be used for testing the alarm light and horn Test position shall be spring loaded and return to the “ ON ” position after release The “ OFF ” Position shall only disable the alarm horn light at the site and will not affect operation of the alarming or sensing circuits 4 “ Alarm Silence ” push button will be provided to silence the alarm horn while leaving the alarm light in operation 5 Automatic insulation tester Meg - Alert motor guard GP - 500 - M shall be used while the motor is idle and shall utilize the included door mounted panel meter Section 5 - 7 WASTEWATER PUMP STATIONS 2024 RevisionPagePage pageNumber8SECTION 5 – WASTEWATER PUMP STATIONS a For stations with soft starts or VFDs , output contactors may be required to isolate motor from drive when idle for testing An alarm output from the device should stop normal operation of the pump if a low insultation resistance is detected 6 For VFD applications that require PLC Control , a color HMI GUI no smaller than 5 - inch by 3 - inch may be used HMI must be approved by the owner , and if not currently owned programming software and program must be provided with the panel to the owner All software if preregistered must be registered in Johnston County Public Utilities name 7 For RVSS soft starter applications a window through the door to see any indications on the front of the RVSS must be provided unless there is a remote indicator mounted to the door 8 For VFD applications , Remote operator indicator must be door mounted 9 Phase Loss detection shall be accomplished with a din rail mounted octal socket style device and shall provide the following at a minimum a Phase Loss b Phase reversal c Adjustable Voltage imbalance d Adjustable restart delay 10 Upon abnormal voltage conditions , “ loss of phase ” indicator should light and normal operation of the pumps should stop 11 Elapsed Time Meter to indicate run hours for each pump shall be required 12 Automatic electric alternator shall be required for pumps with a built in manual override to “ lock ” in a lead pump 13 Lag pump shall have time delay on power fail to prevent multiple pumps from starting concurrently after a power fail event 14 For stations with Generators designed for only single pump operation , a protection circuit must be utilized to prevent a second pump from turning on in “ auto ” if both pumps are called to run while on “ emergency ” power 15 High water alarm relay wired to alarm circuit 16 Seal fail alarm relay wired to alarm circuit 17 Motor Overtemp alarm relay wired to alarm circuit 18 Provide voltage free dry relay contacts for each alarm condition for RTU connections as well as Pump Run and liquid level controls status 19 Contacts should be provided to allow for RTU On Off control of the pumps while they are int AUTO RTU will provide a RTU control override signal 120vac and pump run commands 12vac When RTU energizes circuit this should enable the RTU to turn On Off the pumps , and should energize the “ RTU Control ” light indicator 20 Provide a120VAC alarm light with a red globe and guard or 120VAC weatherproof red Strobe , and horn , loose for external mounting 21 A 120VAC Duplex Weatherproof GFI power receptacle shall be required and mounted externally to the cabinet on either the side or bottom of the cabinet Section 5 - 8 WASTEWATER PUMP STATIONS 2024 RevisionPagePage pageNumber9SECTION 5 – WASTEWATER PUMP STATIONS 22 Approved Intrinsic relays for displacement switches are Warrick Gems 27A1d0 , and Symcom SSAC ISS - 105 - ISO Equals are permitted with prior approval from the owner 23 Provide Branch Circuits as necessary for site D Labeling and identification 1 All wires shall be labeled and correspond to approved drawings 2 Wiring color codes a 480V AC Power i Phase A – Brown ii Phase B – Orange iii Phase C - Yellow iv Neutral – Grey b 120 208V or 120 240V AC Power i Phase A – Black ii Phase B – Red iii Phase C – Blue iv Neutral – White c 120V AC Control i Ungrounded Conductors – Red ii Unground Conductors , foreign source – Yellow d 24V AC Control i All wiring – Orange e 24V DC Power i Positive – Red ii Negative – Black f 24V DC – Control i Ungrounded conductors – Blue ii Grounded conductors – Blue with White Stripe g Equipment grounding conductors i All wiring – Green 3 All conduits shall be labeled at both ends with conduit numbering from the approved drawing set a If a conduit schedule is not provided in drawings , then conduit shall be labeled starting with C and 3 digits Example C - 001 b Conduit labels shall be appropriate for the location they are installed Weather proof , UV rated for example Shelf adhesive labels shall be Vinyl and lettering no smaller than ¼ inch E For each motor 25HP or smaller a magnetic starter with under - voltage release and quick trip ambient - compensated overload protection for each leg shall be provided Starting shall be “ across the line ” Section 5 - 9 WASTEWATER PUMP STATIONS 2024 RevisionPage0SECTION 5 – WASTEWATER PUMP STATIONS F For each motor greater than 25HP a reduced voltage soft starter or variable frequency drive with output contactors shall be required Refer to manufacture specs for proper installation G For stations utilizing VFD and PLC control acceptable PLCs are Allen Bradley Micrologix 1400 , Wago 750 - 8212 , and Wago 750 - 882 PLCs must provide Ethernet communications , and programmable over Ethernet Communications to HMI GUI must be accomplished via Ethernet Contact owner for specific IP addressing to use for the application H Mercury Displacement Switches for Level Controls 1 Float switches shall be of the mercury - tube type or equivalent technology , encapsulated in polyurethane or vinyl floats compatible with waste water applications 2 The units shall be waterproof , shockproof , explosion proof , and equipped with sufficient submersible cable to extend to the control panel without splicing 3 Any required weights shall be provided 4 Switches shall be suspended in the wet well on a suitable stainless - steel rack I Magnetic Flow Meters 1 Required on all stations 2 Must have 4 20mA output 3 Must have remote mounted display to be mounted outside of Vault That does not require the opening or entry of vault to read a Must include Flow rate in gallons per minute and totalization in thousands of gallons per day 4 Acceptable Manufacturers a Emerson Process Control - Rosemount b ABB c Khrone d Endress Hauser J Pressure Indicating Transmitter on Discharge side of pumps measuring system pressure 1 Required all stations 2 Acceptable device a Emerson Process Control – Rosemount Model 3051S b Siemens Sitrans P420 c Endress + Hauser Model Deltabar S PMD75 d JCPU approved Equal 26 Telemetry A Contractor shall furnish through an Approved Control System Integrator , all required work to provide a working wireless telemetry system to remotely monitor and control the pump station from the Owner’s existing SCADA system To include but not limited to the following 1 Antenna 2 Yagi antenna mounting 3 Antenna cable Section 5 - 10 WASTEWATER PUMP STATIONS 2024 RevisionPage1SECTION 5 – WASTEWATER PUMP STATIONS 4 Radio 5 Circuit breakers 6 TVSS 7 PLC 8 Relays 9 Battery backup 10 etc B The contractor is responsible for coordination of SCADA programming and start up C Current Approved System Integrators Additional Integrators may be used with Owner Approval 1 CITI 2 Custom Controls Unlimited LLC 3 Instrulogic Corp LLC D Integrator shall submit all shop drawings for the panels for approval E Integrator shall contact Owner and coordinate locations to conduct a path loss study , and provide documentation of the path loss 1 A fade margin of less than 21dB shall be unacceptable 2 Upon the Owners discretion on marginal or non - line of site paths a physical on - site test of radio communication may be required to “ prove ” the link prior to final approval F The RTU supplied shall have the capability of communication with an existing remote master station 1 It shall accomplish communication using Modbus TCP via a spread spectrum radio Radio type and frequency may vary due to specific networks Contact Owner for exact radio model for the application G The PLC processor shall be a Wago 750 - 882 or 750 - 8212 If HMI is used then integrator must provide programming software if applicable registered in the Owners Name HMI GUI shall communicate via Ethernet to the PLC H RTU will provide at a minimum of sixteen 16 120VAC digital Inputs and four 4 120VAC digital outputs All analog I O shall be individually replaceable multistage surge protection by Phoenix Contact , Citel or equal Refer to contract drawings for additional requirements 1 Typical Input Signals will include a Individual Pump Run Status b Individual Pump Fail Status per pump c Power status d Generator transfer switch status e High Well Float status f Lead Float g Lag Float h Off Float Section 5 - 11 WASTEWATER PUMP STATIONS 2024 RevisionPage2SECTION 5 – WASTEWATER PUMP STATIONS i Low Cut Off Float If equipped j Flow Meter if equipped k Speed feedback if VFD equipped l System Pressure Transmitter if equipped m Wet Well level if equipped 2 Typical output signals will include a Remote Generator Test start gen set with load b SCADA mode enable RTU control c Individual pump run commands I RTUs mounted in a non - conditioned environment shall have a Nema 4X enclosure 316 stainless steel , aluminum , or Fiberglass with continuous single hinge and 3 - point latching handle pad lockable door equal to a Hoffman enclosure RTUs mounted in a conditioned environment shall be of similar material and ratings of the other electrical panels located in the structure The RTU shall include the following as a minimum 1 15A Main breaker 2 Minimum Size of 30 - inches wide by 30 - inches tall by 10 - inches deep , providing enough room for equipment and 20 available space for additional growth 3 Minimum 750VA uninterruptable power supply 4 Corrosion inhibitors installed after testing 5 120VAC Surge protection 6 Enclosure penetrations should be limited to bottom of enclosure on the edges to leave room for placing UPS in bottom of cabinet 7 All wiring and equipment shall be labeled 8 All Field wiring to devices equipment must be surge protected or utilizing dry contacts to form isolated circuits 9 Shop drawings will be provided to Owner for approval 10 Wiring in panel must be secured by wire duct 11 All grounding and neutral wires must have their own path to an internal bus No looping neutrals or grounds from equipment to equipment allowed 12 Comply with UL508 and IEEE standards J Radio Communication Equipment 1 Path Loss Study a Path loss Study must be accomplished and a copy presented to the County before pole height can be approved b A physical on - site test may be used for antenna height verification Submit Path Loss Form with signal information to the County for approval c Any path loss software used must consider most recent terrain data including approximation height of vegetation and buildings 2 Timber Pole and Antenna Mount Section 5 - 12 WASTEWATER PUMP STATIONS 2024 RevisionPage3SECTION 5 – WASTEWATER PUMP STATIONS a Timber Pole will be at a minimum 70ft in length in all applications Exceptions to this must be requested in writing , and an approved documented response from the owner engineer must be provided before any shorter lengths can be provided If shorter length is being consider a physical test and pathloss study must be performed and take into account future growth structures in the area b Path loss study must be performed by the contractor and approved by the County before a determination of required antenna height can be made c The contractor shall provide and install a Class 3 timber pole with antenna vertically mounted 3 - inches from top of one continuous 20 - foot section of 2 - inch schedule 40 RGS pipe which is to be bolted through the pipe and pole using heavy duty galvanized hardware with a minimum thread diameter of 5 8 - inch The pipe shall extend 14 - feet above top of pole and must be aimed according to path loss study requirements i The pole shall have a minimum top circumference and a minimum circumference 6 feet from the butt as required in ANSI 051 - 2002 For a Class 3 , 70 - foot southern pine or Douglas fir pole , the minimum top circumference is 23 - inches and the minimum circumference 6 feet from the butt is 45 - inches ii Timber pole is to be installed in a minimum 30 - inch diameter hole bore and encased in 3000psi rated concrete below grade iii Depth below grade shall be 10 of the length plus 4 feet iv If additional height is required , it shall not be accomplished by adding more than one 20 - foot sections of Rigid Galvanized Steel RGS pipe to the top of the Pole RGS Pipe shall be 2 - inch in diameter , schedule 40 Only one 20 - foot section of RGS pipe is to be used to add height without written consent by the County d If it is determined that antenna height would be sufficient below 30ft and considers future tree growth Contractor can submit alternative methods in lieu of a Timber Pole Such structures must be designed for this type of use and shall be no lower than 12ft above grade Simply threading multiple sections of pipe together to reach this height is not acceptable and must use additional mechanical hardware to prevent rotation of pieces If an area light was to be mounted to the pole than the Contractor will still be required to provide a pole for the area light e Installations that require poles over 90 feet in length require a design by a licensed professional engineer evaluating both pole material and foundation design 3 Coaxial Cable Coax a For typical 902 - 928Mhz applications less than 250 feet in length the coax is to be Times Microwave LMR - 600 or equal b Coax shall have a continuous braided shield Corrugated coax shield will not be acceptable c For other frequency ranges and distances consult with Owner for appropriate cabling requirements Section 5 - 13 WASTEWATER PUMP STATIONS 2024 RevisionPage4SECTION 5 – WASTEWATER PUMP STATIONS d Connectors shall be Type “ N ” and weather proofed according to manufacture specs , or wrapped in rubber splicing tape , with an outer coating of UV rated electric tape coating applied extending past the rubber splicing tape as a minimum e Coax should run along the pole using ½ - inch rubber insulated cable clamps with a maximum spacing of 5 - foot Clamps shall be attached using # 10x2 - 1 2 ” ` exterior wood screws such as Power Pro Premium Exterior Wood Screws f Manufacturer minimum bend radius should not be exceeded at any point of time during installation 4 Grounding a A continuous # 4 bare copper ground wire shall be stapled to the pole , top to bottom , using round crown galvanized staples not more than 5 foot of spacing b Ground wire shall extend to top of pole and shall be attached using grounding clamps to the RGS pipe and spiral around the pipe at no more than 2 foot spacing in continuous contact to top of pipe and connected again with another grounding clamp End of ground wire should form an aerial at least 6 - inches above top of pipe c At a minimum of 10 feet above grade copper ground wire shall be sleeved in 1 - inch PVC Conduit d The grounding coper wire shall be connected to the site ground to form one continuous ground Additional ground rods may be necessary to eliminate ground differential 5 Antenna 902 - 928MHz applications a Yagi antennas shall be used on Endpoints or Point to Point radio communications i Yagi antenna shall be a 10 element 11dBi gain or greater and equipped with a Type N female connector 1 Laird PC8910N formerly Cushcraft 2 PCTEL BMYD8900 3 Or Approved Equal b Omni antennas shall only be used at gateway locations in a Point to Multipoint Application i Andrew CommScope DB589 - Y Collinear Omni Antenna 1115dBi Gain or approved equal c Once installed antennas should be adjusted to achieve maximum signal strength possible 6 Radio 902 - 928MHz applications a Radio types will be dependent upon location and application i Contact owner for specific model ii Typical Models 1 Freewave FGR2 - P 2 Xetawave Xeta9x 3 Intuicom 200 - PEU Section 5 - 14 WASTEWATER PUMP STATIONS 2024 RevisionPage5SECTION 5 – WASTEWATER PUMP STATIONS 4 Schneider Trio JR - 900 b Radio Power output shall be adjusted as required to meet FCC Rules for unlicensed wireless equipment operating in the ISM Bands and is regulated by part 15 of the FCC rules i Maximum transmitter output power , fed into the antenna , is 30 dBm 1 watt ii Maximum Effective Isotropic Radiated Power EIRP is 36 dBm 4 watt iii You can obtain the EIRP by simply adding the transmit output power , in dBm , to the antenna gain in dBi if there is loss in the cable feeding the antenna you may subtract that loss K Final testing 1 Radio a Once installed Signal Strength , Noise levels , VSWR , Transmit , Receive , should be documented and turned in to the Owner for review 2 Antenna a Installed height , true azimuth angle , vertical angle shall also be documented and copies given to the Owner 3 Other a Any other pertinent information related to the installation should be noted 27 Payment on County Funded Projects A For County funded projects , work bid price to include at minimum a 70 - foot transmission grade class 3 timber pole Additional height may be required based upon the path loss study Additional height up to 20 - feet shall be reimbursed for additional material and shipping cost only B If an engineer solution is required for a pole greater than 90 - feet in length a change order will be negotiated 28 Lighting A Pole Lighting 1 A 150 - watt metal halide luminary Area light or LED equivalent shall be provided on a 24 - inch arm mounted to a pole 15 - feet above grade A photocell for the light will be mounted 6 foot above grade with a weatherproof on off switch mounted to the pole approximately 4 - foot above grade The area light shall be certified as Dark Sky Friendly 29 Wet well and Appurtenances A Pump station wet well shall be precast concrete with monolithic base Minimum dimensions shall be as indicated on the Plans The precast wet well shall meet ASTM C913 and ASTM C478 specifications A thicker base shall be provided if required to prevent flotation A minimum 12 - inches thick foundation shall be provided for the wet well base Concrete shall be reinforced to withstand the internal and external loads indicated plus a 100 - psf live load on the Section 5 - 15 WASTEWATER PUMP STATIONS 2024 RevisionPage6SECTION 5 – WASTEWATER PUMP STATIONS top slab The Contractor must backfill around the wetwell and surrounding structures to meet 95 compaction It shall be the Contractor’s responsibility to haul in select material , if needed B Joints shall be sealed with butyl rubber mastic Ramneck , or “ O - ring ” gasket installed in accordance with the manufacturer’s instructions All joints shall be parged on the interior and exterior with type “ C ” mortar C Interior of wet well and piping inside wetwell shall be factory or “ field ” epoxy coated to a minimum 50 mil surface dry thickness Epoxy sealer prime coating and finish coating shall be NSP 100 and NSP 120 , respectively , Carboline , or approved equal If the wet well is factory epoxy coated , touch - up “ field ” coating will be required Field epoxy or corrosion conditional concrete must be installed by a certified applicator of the approved product unless approved by the County D The wet well shall have , mounted at 18 - inches above wet well top , a stainless - steel junction box to enable quick disconnect of power leads to pump motors when pulling pumps out for maintenance E The wet well shall be equipped with an aluminum access hatch as shown on the plans that shall be of adequate dimensions to pull out pumps with no obstruction F All bolts , brackets , hardware , etc for fastening items or bolting piping located in the wetwell shall be STAINLESS STEEL , 316L or coated with Tripac Blue 2000 G Inflow and outflow pipe connections to wet well shall be sealed using GPT Industries ’ Link - Seal or approved equal H A sloped invert of non - shrink grout shall be constructed at the base of the wetwell The invert shall have sufficient slope to prevent build - up of solids in the wetwell bottom Contractor shall meet the recommended manufacturer clearance are meet from the pump volute to the wet well bottom I Aluminum access hatches shall be exterior sidewalk , single or double leaf type as required or shown suitable for 300 psf live load Doors shall be equipped with slam lock , and automatic hold - open arm with release handle , safety chain , and compression spring operator The frame shall be provided with drainage channel Hatches shall be Type “ J ” or “ JD ” as manufactured by the Bilco Company , Darp Associates , Haliday , or equal For 6 - feet to 8 - feet diameter structures , Halliday type RIR hatches are preferred Hatch way shall include fall through protection meeting OSHA and ANSI requirements 210 Valve Vault A Valve vault shall be precast concrete with monolithic top and bottom as indicated on the plans B Vault shall have an aluminum access hatch as shown on the plans C A duplex receptacle shall be installed in the vault within 6 - inches of the top of the structure to provide power to the sump pump D Valve Vault shall have a sump pit as shown on plans Section 5 - 16 WASTEWATER PUMP STATIONS 2024 RevisionPage7SECTION 5 – WASTEWATER PUMP STATIONS E Valve Vault shall have a minimum of one air release valve installed on the pump discharge piping ARI – Nylon model D025 or similar F Check valve shall be of the horizontal swing type with an outside weighted swing arm G A ¼ - inch NPT tap for pressure gages shall be supplied on both sides of the check valve for each pump One 1 pressure gage shall be installed on the discharge side of the check valve for each pump H Sump Pump 1 One 1 automatic submersible sump pump , with a rated capacity of ten 10 GPM at 10 - feet TDH shall be installed in the equipment capsule sump 2 The sump pump shall be complete with a fractional horsepower motor , oil filled and hermetically sealed , designed to operate at 1,800 rpm , on a 120 - volt , single phase , AC power source and draw no more than 42 amps 3 A Buna - N shaft seal shall prohibit the pumped fluid from entering the motor housing 4 The pump body shall be constructed of aluminum and polypropylene and the motor casing shall be cast aluminum 5 The impeller shall be of polypropylene plastic and affixed to a 304 - grade stainless steel shaft 6 The sump pump will be “ clog - proof ” energy efficient design with built in thermal protection 7 There shall also be included as an entering component of the pump , a built - in check valve on the discharge 8 The sump pump shall operate within an approximately 35 - inch range turning on at approximately 5 - inches and off at approximately 25 - inches of depth in the sump Therefore , the sump pump will initiate a pumping cycle before the sump is filled 9 The pump float shall operate by sliding up and down a fixed bar 10 The sump pump discharge piping shall be size 1 ½ - inches schedule 80 PVC with solvent weld connections 11 The discharge piping system will be complete with a union connection located on the upper and lower halves of the discharge line 12 A PVC ball valve shall be installed on the discharge side of the check valve to enable maintenance of check valve without draining entire sump discharge line 13 Pump shall discharge into wetwell approximately 12 - inches – 18 - inches from the top of the wet well 211 Power Loss Operation A The pump station shall be equipped with either standby power meeting the requirements of Section 6 B Power loss operation capacity shall be sufficient to meet the FIRM capacity of the station as indicated on the permit Section 5 - 17 WASTEWATER PUMP STATIONS 2024 RevisionPage8SECTION 5 – WASTEWATER PUMP STATIONS 212 Trash Basket Grinder A A type 304 stainless steel or aluminum trash basket shall be mounted on “ sliding ” rails which shall be anchored with stainless steel anchors into a separate manhole outside the wet well for circular wet wells B For rectangular wet wells , the basket screen may be installed within the wetwell C Basket shall be at least 18 - inches deep for 8 - inch sewers and 24 - inches deep for larger sewers D Basket shall have maximum 2 - inch diameter openings and an open top E A lifting bail and stainless - steel lifting drain shall be provided F For baskets mounted in a separate manhole , the vertical drop between inlet and outlet sewer inverts shall be at least 15 - feet 1 The manhole shall be factory epoxy coated as described in section 271 A Thern Model 5110 hoist shall be provided for basket removal Min 30ft lifting cable G Grinders 1 Pump stations – 200 GPM or greater in separate manhole outside the wet well H In - Channel Grinder greater than 120 GPM station 1 Grinder also referred to as “ solids cutter ” shall be of two - shafted design consisting of individual cutters and spacers driven by hexagonal shafts 2 The cutters shall actively grab and pull material into the stack for shredding 3 Grinder shall have upper and lower end housings to retain shaft support bearings and seals 4 Side rails shall provide structural rigidity while optimizing throughput and capture 5 Grinder shall have a motor and speed reducer to drive the cutter shafts 6 The equipment shall operate at low speed with a maximum cutter shaft speed of 60 rpm and shall be specifically designed for capturing and shredding wipes 7 Cutting stack shall be of nominal height listed in performance requirements , and shall consist of interleaved cutters and spacers 8 Cutters shall have 17 teeth , have a 0 438 ” nominal thickness , and have a wipes - ready design 9 Cutters shall have radial serrations on the leading edges designed to perforate material as it passes between the cutter and adjacent spacer 10 Spacers shall be 0446 ” nominal thickness 11 Cutters and spacers shall be individual disks constructed of heat - treated alloy steel 12 Spacers shall have a knurled outside diameter designed to aid in tearing of material as it passes through the cutter stack 13 Cutter tooth height shall be not greater than ½ - inch above the root diameter of the cutter 14 Cutter outside diameter shall not exceed a maximum 471 15 Cutter thickness tolerance shall be + 000 - 001 ” 16 Spacer thickness tolerance shall be + 001 - 000 ” 17 Clearance between any cutter tip and adjacent spacer shall be nominal 0015 ” 038 mm Section 5 - 18 WASTEWATER PUMP STATIONS 2024 RevisionPage9SECTION 5 – WASTEWATER PUMP STATIONS 18 Cutters shall be heat treated to 45 - 53 HRc , and spacers shall be heat treated to 34 - 53 HRc 19 Spacers shall have a smooth outside diameter 20 Cutter to cutter clearance shall be a maximum of 0010 ” 21 Shafts shall be hexagonal , 2 ” across flats 22 Shafts shall be of heat treated 4140 alloy steel with a minimum tensile strength of 149,000 psi 23 Shaft hardness shall be 38 - 42 Rockwell C 24 Side rails shall be constructed of ASTM A536 ductile iron 25 Cutter side rail shall have evenly spaced horizontal fingers Fingers shall be designed to create a pressure differential towards the center of the grinder , directing solids into the cutter stack , while at the same time minimizing overall pressure drop through the grinder 26 Radial and axial loads shall be borne by sealed , oversized , deep groove ball bearings a Shaft seal type shall be mechanical b Each bearing and seal arrangement shall be incorporated into a cartridge - style housing c Cutter shafts shall be supported on both ends Cantilever - style arrangements shall not be permitted d Dynamic and rotating seal faces shall be Tungsten Carbide with 6 Nickel binder e Seal cartridges shall be rated to a maximum pressure of 90 psi f O - rings shall be of BUNA - N g Seal cartridges shall not require flushing h Seals shall be rated to operate wet or dry i Housings and top cover shall be of ASTM A536 ductile iron j Bottom cover shall be of A36 carbon steel k End housings shall have integral bushing deflectors to guide solids away from seal cartridges 27 Transfer gears shall be of involute profile and fabricated from heat treated alloy steel a Transfer gear tooth design , thickness and hardness shall be suitable to transfer torque between shafts up to the rated breakdown torque of the motor b The interface between transfer gears shall be factory lubricated with grease to minimize wear c The transfer gear ratio shall be such that the ratio of cutter tip speed of the low - speed shaft to cutter tip speed of the high - speed shaft shall be greater than 090 and less than 100 to promote tearing of material as it passes through the cutter stack and at the same time facilitate cleanout of material from between the cutters d Low speed coupling shall be a 3 - jaw type i The 3 - jaw halves shall be of hardened 4140 alloy steel Section 5 - 19 WASTEWATER PUMP STATIONS 2024 RevisionPage0SECTION 5 – WASTEWATER PUMP STATIONS ii Each low - speed coupling half shall be encapsulated on its mating shaft to facilitate proper engagement of coupling lobes 1 16 ” – 1 8 ” iii The interface between low - speed coupling halves shall be factory lubricated with grease to minimize wear e Speed reducer shall be manufactured by Sumitomo Machinery Corporation of America i Speed reducer shall be a cycloidal type , with a speed reduction ratio shall be 29 1 ii Speed reducer shall be grease lubricated f High Speed coupling shall be a 3 - jaw type with elastomer spider i The 3 - jaw halves shall be of sintered iron ii The spider shall be of BUNA - N 28 Motor shall be manufactured by Baldor Electric Company a Motor shall have characteristics as listed in Performance Requirements 29 Grinder shall be fitted with two 2 lifting rings 213 Odor and Corrosion Control A The County reserves the right to require on station 120 GPM or greater to be equipped with the liquid bioxide odor control system BIOXIDE VDLT Chemical Feed System Evoqua or equivalent that meets all containment and safety requirements B The County requires a carbon filter order control system to be installed at all pump station locations situated within 500 ft of a residential or commercial property line 3 Installation , Inspections and Testing 31 Installation A Rock Removal , Blasting 1 In rock or other unyielding material , the excavation shall be made at least 6 - inch below subgrade elevation The excavation shall be refilled with select material compacted in place as specified for ordinary excavation Suitable material from excavation may be used , if available If not , it shall be hauled in 2 All blasting , where required , shall be done under the personal supervision of someone thoroughly skilled in this class of work All necessary measures to protect life and property shall be taken When in close proximity to buildings , transmission lines , telephone lines or other facilities , timber mats or other means of preventing damage from flying debris shall be used Ample and suitable signals shall be given in proximity to the work before each blast , and flagmen shall be placed on all roads , beyond the danger zone , in every direction to warn traffic All responsibility for damage rests on the Contractor 3 Prior to any blasting , a pre - blast survey must be conducted including an evaluation of any structures within 500 - feet of the proposed blasting The survey shall also determine well recover rates for any water supply wells within 100 - feet of the proposed blasting The Contractor shall not contact property owners directly for pre - blast surveying until the County Section 5 - 20 WASTEWATER PUMP STATIONS 2024 RevisionPage1SECTION 5 – WASTEWATER PUMP STATIONS has first provided notification to affected residents The County is not responsible for any delays associated with pre - blast surveying or notifications 4 The approved NCDOT Encroachment Agreement for the project does not allow blasting in the NCDOT right - of - way If the contractor wishes to perform blasting in the right - of - way , it shall be the responsibility of the contractor to provide any necessary information to NCDOT and acquire the revised encroachment agreement The Owner shall not be responsible for any delays associated with seeking blasting approval from NC DOT 5 Submittals required for blasting approval a Names , addresses , telephone numbers , and qualifications of the blasting subcontractor s and explosive supplier s that will be used Contact and licensing for the designated Blaster - In - Charge b Copies of certificates of completion of specialized training for the handling of explosives for the designated Blaster - In - Charge , blasting foreman and any other key personnel responsible for the work c A blasting plan , indicating the methods , materials , and equipment to be used The blasting plan shall indicate the types of explosives , drilling patterns , and general layout to be used to execute the work A licensed blaster shall select the materials and design the blasting pattern The blasting plan shall include a schedule The plan shall meet all State regulations and be sealed by a professional engineer licensed in the North Carolina d A ground vibration and air blast monitoring plan , indicating structures that will be monitored , monitoring equipment that will be used , and personnel responsible for the monitoring 6 A minimum of 24 hours prior to each round of blasting , the Contractor shall submit a detailed blast round design plan to the Engineer’s on - site representative The blasting plan submitted is for quality control and record keeping purposes Review by the Engineer shall not relieve the Contractor of his responsibilities as provided herein The blast round design submittals shall include a Location state grid coordinates and limits of the shot b Number , diameter , and depth of blast holes to be detonated in the round , and a plan showing drill hole pattern , spacing and distance to the free face c Depth of overburden d Types and total weight of the explosives to be used in the round e Loading diagram showing the location of explosives , primers , and initiators ; location , depth , and type of stemming to be used in each hole f Initiation sequence , including delay timer and delay system , total weight of explosive to be detonated on each delay , and a list of timing of delays g Manufacturer’s data sheet for all explosives , primers , and initiators used h Planned seismic monitoring positions , distances from the blast round , and seismograph types to the used to monitor vibrations and air blast overpressures Section 5 - 21 WASTEWATER PUMP STATIONS 2024 RevisionPage2SECTION 5 – WASTEWATER PUMP STATIONS i Type and amount of blasting mats and or depth of soil cover to be used over the top surface of the shot j Any other information required by applicable State and Federal regulations 7 The Contractor and subcontractor s shall comply with all applicable Federal , State , and local codes , laws , rules and regulations as well as professional society standards for the storage transportation and use of explosives 8 Blasting is subject to the following warning levels and not to exceed limits Variable Warning Level Not - to - Exceed Limit Vibration PPV gt; 40 Hz 075 in sec 19 mm sec 10 in sec 25 mm sec Vibration PPV lt; 40 Hz 040 in sec 10 mm sec 05 in sec 13 mm sec Air - overpressure noise 120 dBL 133 dBL 9 Post - Blast Reporting – within three 3 days of each blast , the Contractor shall submit post - blast reports including the following information at a minimum a Results and effectiveness of the blast and any proposed changes to subsequent site - specific blast plans b Blast monitoring report i Type , identification and specific location of monitoring equipment ii Distance and direction of blast iii PPV in each direction and peak vector sum iv Maximum air - overpressure c Blast damage report when necessary d Drilling records including blast pattern and blast hole drill logs 10 Rock Excavation for trenches and pits includes removal and disposal of materials and obstructions encountered that cannot be excavated with a track - mounted power excavator , equivalent to Caterpillar Model No 330 CL , and rated at not less than 247 HP flywheel and 66,094 - pound drawbar pull and equipped with a short stick and a 30 - inch - wide , tight tip radius rock bucket with rock teeth rated at 075 cubic yard heaped capacity 11 Typical of materials classified as rock are boulders one - half 1 2 cubic yard or more in volume , solid rock , rock in ledges , and rock - hard cementitious aggregate deposits 12 Intermittent drilling , blasting , or ripping performed to increase production and not necessary to permit excavation of material encountered will be classified as earth excavation 13 Do not perform rock excavation work until material to be excavated has been cross - sectioned and classified by the Owner’s representative , and such information provided to the Engineer for approval 14 Rock shall be defined as that solid material that cannot be excavated under the conditions stated above All blasting shall be done after coordination with the County representative and Section 5 - 22 WASTEWATER PUMP STATIONS 2024 RevisionPage3SECTION 5 – WASTEWATER PUMP STATIONS subject to all applicable regulations The County reserves the right to require the removal of rock by means other than blasting where any pipe or conduit is either too close to or so situated with respect to the blasting as to make blasting hazardous Rock taken from the ditch shall immediately be hauled away and disposed of by the contractor at his expense B Equipment C The Contractor shall install all pumps , motors , variable speed drives , and controls specified herein in accordance with the plans and as recommended by the manufacturer Pump manufacturer shall provide pumps , motors , variable speed drives , controls and all other necessary items to make a complete installation The Contractor shall take possession of all pumps and equipment when delivered D Backfilling 1 All trash , forms , debris , and other foreign material shall be cleared from around all pipes and structures before backfilling 2 Backfilling of trenches shall be completed after the installation of each section of pipe Backfilling shall be kept up with the pipe laying to the satisfaction of the Engineer 3 Backfilling around the pipe and to a depth of at least 1 above the top of pipe shall be placed by hand in layers of not over 6 - inch 4 Only select material containing no rocks or other objectionable material shall be used for this portion of the backfill 5 As fast as the material is placed , it shall be cut under the haunches of the pipe with a shovel and thoroughly compacted with mechanical tamps for the full width of the trench to provide support for the bottom and sides of the pipe 6 Filling shall be carried up evenly on both sides 7 A representative for the County shall inspect the subgrade before the setting of the wet well County reserves the right to require a geotechnical 8 Soil shall be backfilled around wetwell and other structures in 1 - foot lifts or shallower and shall be compacted to 95 Standard Proctor maximum dry density at optimum moisture content Testing reports from an independent geotechnical for every 2 - feet lift 9 The balance of the backfill shall be placed and tamped to prevent excessive settlement in a manner satisfactory to the Engineer If the trench backfill is located under miscellaneous paved areas , areas to be paved , or unpaved streets , the trench shall be backfilled with suitable material free from large stones or clods in 8 - inch layers loose measurement and thoroughly tamped and compacted to 95 of maximum as established by AASHTO specification T99 , method A , with mechanical tampers , so as to avoid future settlement Where applicable , the compaction shall be acceptable to the Department of Transportation or Owner For trenches located in streets and highways trench backfilling shall be in accordance with the requirements of item 3112 of this section , Cutting and Replacing Pavement 10 For pipe outside street limits , compaction shall be at least 90 of maximum as established by AASHTO Specification T99 , Method A Section 5 - 23 WASTEWATER PUMP STATIONS 2024 RevisionPage4SECTION 5 – WASTEWATER PUMP STATIONS 11 Excess material shall be promptly removed from the site , and the pavement or road surface cleaned of objectionable material The pavement and or road surface shall be cleaned daily with a mechanical broom and or washed if requested by the Engineer The Contractor shall correct any future settlement within the guarantee period 12 In unpaved streets and shoulders the top 6 - inch of trench shall be filled with well compacted crusher - run stone In paved areas the top of the trench shall be filled with the specified base for pavement , well mixed and compacted Any settlement of backfill below finish grade shall be promptly corrected 13 On outfall lines and at other points where damage to the system or property will not occur , the backfill material more than 1 above the top of the pipe may be placed in 12 - inch layers and compacted with mechanical tamps The upper portion of the backfill , more than 5 - feet above the pipe may be compacted by rolling with wheeled equipment Excess material may be mounded on the trench The Contractor will be responsible for all final subsidence of all trenches and shall leave the same flush with the original ground after all settlement has taken place Trenches must be protected against scour due to surface drainage 14 Backfilling around manholes shall , in general , conform to requirements for backfilling trenches , except that no backfill shall be placed around manholes until all mortar has properly set , and backfilling shall be carried up symmetrically around structures E Painting & Touch - Up 1 All metal components with the exception of the stainless steel guide rails shall be painted in accordance with Section 273 2 After all equipment and appurtenances have been installed , the Contractor shall touch - up any abrasions , scratches , or patches in the surface protection of any furnished item of work Any mud , grease , or other extraneous material shall be removed from the completed work using suitable solvents or detergent solutions 3 Galvanized conduit pipe threads shall be touch - up painted 4 The wet well interior and piping shall be touch - up painted with epoxy sealer prime coating and finish coating as approved by the epoxy lining manufacturer F Repairs to Wet well 1 All openings made in the wetwell for anchorages , conduit runs , pipe runs , etc , shall be sealed using a cement grout The grout shall be neatly applied to the vacancy and shall be troweled in , and excess grout shall be immediately removed from the wetwell Grout shall be high strength , non - shrink type 32 Inspections A The manufacturer’s field engineer or representative shall inspect and check the installation after erection and prior to start - up and shall certify that the completed installation is ready for start - up The manufacturer’s field representative shall check the proper rotation , operating speed , and starting and running electrical characteristics of the operational pumping equipment and certify that they are correct The field representative shall also make himself Section 5 - 24 WASTEWATER PUMP STATIONS 2024 RevisionPage5SECTION 5 – WASTEWATER PUMP STATIONS available to the Owner’s operating staff in addressing operational and trouble - shooting concerns that they might have The Contractor shall provide labor , testing water and shall assist the Engineer in performing field testing to check operating conditions of all pumps The testing procedures shall be performed by the Contractor B The manufacturer’s representative shall provide a written start - up report and six 6 copies of Operation and Maintenance Manuals 33 Testing A All testing shall comply with Section 8 of these documents B Testing Spark - Holiday testing coating C County also reserves the right to require adhesion testing D Spare pumps – with drop wire END OF SECTION Section 5 - 25 WASTEWATER PUMP STATIONS 2024 RevisionPage