SECTION 221353.pdf

SECTION 221353 – ONSITE WASTEWATER TREATMENT SYSTEMS

PART 1 – GENERAL

1.1 RELATED DOCUMENTS

A. Drawings and general provisions of the Contract, including General and Supplementary Conditions and Division 01 Specification Sections, apply to this Section.

1.2 DESCRIPTION

A. This section pertains to the complete construction of an onsite wastewater treatment and disposal system. The system consists of a filtered septic tank; an absorption field dosing tank with a time controlled duplex pumping system; a flow meter and vault; an absorption zone distribution valve and vault; absorption zone pressure distribution manifolds; and, absorption trenches with plastic infiltration chambers.

B. The onsite wastewater treatment system shall be complete and operable. Work or materials that is not specifically mentioned or presented that is reasonably considered ancillary to a complete and functioning system shall be performed by the contractor the same as if described in these specifications and accompanying plans.

1.3 SUMMARY

A. Section Includes:

1. Septic tank.

2. Tank risers.

3. Septic tank effluent filter.

4. Pump tank.

5. Duplex submersible pumping system.

a. Submersible effluent pumps.

b. Pump discharge valve and hose assembly.

c. Pump filter vault.

d. Control and alarm floats.

e. Pump controller and panel.

6. Flow meter.

7. Zone distribution valve.

8. Pressure distribution manifold.

9. Valve vaults.

ONSITE WASTEWATER TREATMENT SYSTEMS 221353

10. Plastic absorption trench chambers.

B. Related Sections include the following:

1. Division 22 Section "Facility Sanitary Sewers” for construction of pressurized and non-pressurized sewer lines.

2. Division 32 Section “Turf and Seeding” for seeding of disturbed areas and absorption trench fields.

1.4 SUBMITTALS

A. Product Data: For each type of product indicated. As applicable to the product, include fabrication, assembly and installation details; material descriptions, dimensions of individual components; rated capacities; operating characteristics;

electrical characteristics; and, furnished specialties and accessories.

1. Septic tank.

2. Tank risers & lids.

3. Septic tank effluent filter and support system.

4. Pump tank.

5. Submersible effluent pumps.

6. Pump discharge, valve and hose assembly.

7. Pump filter vault.

8. Floats.

9. Pump control and system alarm panel.

10. Flow meter.

11. Zone distribution valve.

12. Pressure distribution manifold.

13. Valve vaults.

14. Plastic absorption trench chambers.

B. Wiring Diagrams: For power, signal, and control wiring.

C. Operation and Maintenance Data: For each type of product indicated. Include two (2) copies of manufacturer’s operation and maintenance manuals.

1. Septic tank effluent filter.

2. Submersible effluent pumps.

3. Pump control and system alarm panel.

4. Zone distribution valve.

1.5 QUALITY ASSURANCE

A. Electrical Components, Devices and Accessories: Listed and labeled as defined in NFPA 70, by a qualified testing agency, and marked for intended location an application.

B. Pumps shall be CSA and UL listed as a submersible effluent pump.

C. Pump control and alarm panels shall be UL 508 or UL 698A for Class 1, Division 1 and NEMA4X for use in wet locations and the manufacturer/fabricator will have at least 5 years experience in the fabrication of wastewater system control panels.

1.6 PRODUCT DELIVERY, STORAGE AND HANDLING

A. Do not deliver products to the job site earlier than one week prior to scheduled commencing of installation.

B. Storage and handling of products at the job site shall in no way impair or damage the products.

PART 2 – PRODUCTS

2.1 SUBSTITUTIONS

A. Substitutions to the recommended equipment specified will be permitted with the express written approval of the CONTRACTING OFFICER. Substitutions will be approved only when the substituted item is equivalent or better in quality and performance than the item originally specified or as identified in these specifications. The final determination for “equivalents” rests with the

CONTRACTING OFFICER.

2.2 GENERAL WASTEWATER TREATMENT SYSTEMS

A. Septic Tank and Pump Tank

1. Tanks shall be single wall fiberglass underground storage tanks for water and sanitary wastewater storage as manufactured by Containment Solutions or Xerxes Corporation.

2. Septic tank nominal capacity shall be 8,000 gallons and the nominal diameter shall be 8’.

3. Pump tank nominal capacity shall be 2,000 gallons and the nominal diameter shall be 6’.

4. Schedule 40 PVC pipe stubs and tees shall be factory installed.

5. Tanks shall include a 3” diameter threaded fitting on the top of the tank for installation of a 3” dia. vent pipe.

6. Tank access openings shall be compatible with the specified PVC risers and shall be sized accordingly.

B. Tank Access Risers and Lids

1. Tank access risers shall be constructed watertight and made of ribbed PVC pipe such as Ultra-Rib or Perma-Loc brand as manufactured by Orenco Systems, Inc. Risers shall be compatible with tank access openings and shall be sealed to the tank access openings with a 2-part epoxy such as Model MA320 or a single part adhesive such as Model ADH100, both manufactured by Orenco Systems, Inc. Risers shall include female treaded adapters for bolted anchoring of compatible access lids.

2. Lids shall provide a secure covering for access risers and shall be capable of supporting a 2,500 lb wheel load. Lids shall be provided with polyurethane, neoprene, or EPDM gaskets to ensure a watertight seal.

Lids shall come with SS bolts for securing to tank access risers.

3. Risers will be supplied with rubber grommets for creating watertight pipe penetrations. Grommets shall be secured to risers with a single part adhesive such as ADH100 manufactured by Orenco Systems, Inc.

4. To ensure compatibility, one single manufacturer shall supply tank risers, lids, pipe seals, conduit seals, and anchoring mechanisms.

C. Septic Tank Effluent Filter

1. The septic tank filter shall be a commercial grade gravity flow septic tank effluent filter Model FT 1260-36AR by Orenco Systems, Inc. The filter shall be capable of filtering 1/8” or larger solids. The filter shall be rated for a mean cleaning time of greater than five (5) years at a design flow of 5,000 gpd. The filter shall be easily removable for servicing. The filter and filter housing will be completely removable from a slide rail for reuse in a secondary septic tank to be installed in a future phase of site development.

2. The filter unit will include an integral float tree with mercury type high-level alarm float.

3. Splice Box

a. A signal wiring splice box shall be provided inside the tank access riser. The splice box shall include watertight cord grips and shall be UL listed and NEMA4X rated for use in wet locations. The conduit to the splice box shall be sealed with a watertight and gas tight mechanical conduit seal outside the access riser.

D. Duplex Submersible Pumping System

1. Submersible Pumps

a. Submersible pumps shall be high head effluent pumps Model PF500511 by Orenco System, Inc. The pumps shall be capable of producing 50 gpm at a total dynamic head of 40 feet.

b. General Specifications:

• 0.5 hp, 1-PH, 115V, 12.1A(at design flow)

• 2-impellers

• 2” discharge

• Minimum liquid level of 24”

• Rated for 300 cycles per day

• 24-hr run-dry capability with no deterioration in pump life or performance

• 1/8 inch bypass orifice to ensure flow recirculation for motor cooling and prevent air bind

• Type SOOW 600-V motor cable suitable for Class 1, Division

1 and Division 2 applications

• 5-yr manufacturers warrantee on pump or retrofit liquid end from date of manufacture against defects in materials or workmanship

c. Materials of Construction:

• Discharge: Glass-filled polypropylene or stainless steel

• Discharge bearing: Engineered thermoplastic (PEEK)

• Diffusers: Glass-filled PPO (Noryl GFN3)

• Impellers: Noryl GFN3

• Intake screen: Polypropylene

• Suction connection: Stainless steel

• Drive shaft: 7/16 inch hexagonal stainless steel

• Coupling: Sintered stainless steel

• Shell: Stainless steel

• Motor: Franklin motor exterior constructed of stainless steel.

Motor filled with deionized water and propylene glycol for constant lubrication. Hermetically sealed motor housing to ensure moisture-free windings. All thrust absorbed by Kingsbury-type thrust bearing. Rated for continuous duty.

Single-phase motors and 200 and 230 V 3-phase motors equipped with surge arrestors for added security. Single-phase motors through 1.5 hp (1.11 kW) have built-in thermal overload protection, which trips at 203-221’ F (95-105’ C).

2. Pump Discharge Valve and Hose Assembly

a. The pump discharge assembly shall allow for easy removal of each pump while allowing for operation of a single pump. The assembly will be constructed to drain back following an individual pump cycle by use of a 1/8 diameter weep hole in the discharge pipe above the check valve and below the tank low liquid level.

The assembly shall be 2” diameter SCH-40 PVC pipe and PVC flexible hose and include a SCH-40 check valve immediately after the each pump discharge, a quick disconnect or union for easy pump removal and a ball valve to isolate each pump discharge.

Each pump discharge assembly will penetrate the riser with a watertight seal to an external flex hose wherein the flex hoses will be joined to a single 2” SCH-40 pipe.

3. Pump Filter Vault

a. The pump filter vault shall be Model PVU68-1819 by Orenco Systems, Inc. The vault shall include bracket for hanging from inside rim of tank at the bottom of the access riser. The pump filter vault shall include an integral filter measuring 18” in height and an integral float tree with four (4) adjustable floats.

4. Pump Control and Alarm Floats

a. The float switch assembly shall be manufactured by Orenco Systems, Inc. and be integral to the pump vault. The floats shall be mercury filled floats, signal rated an approved for use with intrinsically safe, Class 1, Division 1 applications. The float tree shall be removable without having to remove the pump vault or pumps. The float tree shall come with four (4) floats with the following configuration.

Level 4 - Lag enable and high-level alarm Level 3 - Timer override Level 2 - Timer on/off Level 1 - Redundant off and low-level alarm

5. Splice Box

a. A pump power cord and signal wiring splice box shall be provided inside the tank access riser. The splice box shall include watertight cord grips and shall be UL listed and NEMA4X rated for use in wet locations. The conduit to the splice box shall be sealed with a watertight and gas tight mechanical conduit seal outside the access riser.

6. Alarm and Pump Control Panel

a. The alarm and control panel shall be for both the operation of the pumping systems and the septic tank high-level alarm. The panel shall be UL 508 or UL 698A for Class 1, Division 1 and NEMA4X for use in wet locations. The panel shall include a visual light alarm and an audible alarm on the top of the panel. The panel shall include a dead-front to mount all operator devises and to protect devices and labels from the elements. Welded on mounting feet shall be provided; they shall be oversized to readily accommodate mounting the panel on 1 5/8-inch strut. All hardware shall be corrosion resistant. The operator devises shall be labeled to correctly indicate proper function.

b. The controller shall be a PLC based controller for control and operation of a duplex pumping system with time-based functionality. The four (4) pump control floats have the following configuration:

Level 4 - Lag enable and high-level alarm Level 3 - Timer override Level 2 - Timer on/off Level 1 - Redundant off and low-level alarm

The controller shall also signal a high liquid level condition in the septic tank.

c. Standard Components:

• Programmable Logic Unit: 115/230 VAC programmable logic unit with built-in LCD screen and programming keys. Provides control functions and timing for panel operation.

• Motor-Start Contactors: 115 VAC: 14 FLA, 3/4 hp, 60 Hz; 2.5 million cycles at FLA (10million at 50% of FLA). 230 VAC:

14 FLA, 2 hp, 60 Hz; 2.5 million cycles at FLA (10million at

50% FLA).

• Toggle Switches: Single-pole, double-throw MOA switch. 20 amps, 1 hp.

• Controls Circuit Breakers: 10 amps, OFF/ON switch. Single-pole 115 VAC. DIN rail mounting with thermal magnetic tripping characteristics.

• Pump Circuit Breakers: 20 amps, OFF/ON switch. Single-pole 115 VAC, double-pole 230 VAC. DIN rail mounting with thermal magnetic tripping characteristics.

• Audio Alarms: 80 dB at 24”, warble-tone sound.

• Visual Alarms: 7/8” diameter red lens, “Push-to-silence.”

NEMA 4, 1-watt bulb, 115 VAC.

• Panel Enclosure: Dimensions as required to include applicable controls and wiring. Constructed of UV-resistant fiberglass;

hinges and latch are stainless steel. To include dead-front.

Conduit couplings provided.

• Event Counters: 115 VAC, 6-digit, non-resettable.

• Elapsed Time Meters: 115 VAC, 7-digit, non-resettable. Limit of 99,999 hours; accurate to 0.01 hours.

• Pump Run Lights: 7/8” green lens. NEMA 4, 1-watt bulb, 115

VAC.

• Heater: Anti-condensation heater. Self-adjusting: radiates additional wattage as temperature drops.

• Intrinsically Safe Control Relays: 115 VAC. Listed per UL 913, for Class 1 Div. 1, Groups A, B, C, D hazardous locations.

• Current Sensors: 115 VAC. Go/no-go operation. Pump fail indicator light on panel. Manual reset switch

• Dry contacts for optional remote alarm.

• Automatic phone dialer capable of dialing up to four (4) different numbers in the event of an alarm condition.

E. Flow Meter

1. The flow meter shall be Model FM200 by Orenco Systems, Inc. The meter shall record cumulative flow with an odometer-type totalizer and be rated for 8 to 80 gpm with a maximum head loss of 3 ft at 50 gpm.

2. Materials of Construction

• Main case: Bronze

• Register box: Bronze

• Bottom Plate: Bronze

• Casing Bolts: Stainless steel

• Magnets: Plasticized material

• Strainer: Synthetic polymer

• Flanges: Bronze

F. Zone Distribution Valve

1. The zone distribution valve shall be a mechanically operated sequential valve with one (1) 2” inlet and four (4) 2” outlets. The outlets pipes shall include a section of clear pipe to visually inspect which outlet is operating.

The valve shall have a removable cam to allow operation of three (3) to four (4) outlets. The valve will be installed with the cam set to three outlets and the fourth outlet shall be plumbed but not used at this time.

The valve shall be Model V6403A by Orenco Systems, Inc.

2. Materials of Construction

• Fittings: Schedule 40 PVC

• Unions: Schedule 80 PVC

• Ball valve: Schedule 40 PVC

• Clear Pipe: Schedule 40 PVC

• Distributing Valve: High-strength noncorrosive ABS polymer, stainless steel, and die cast metal

G. Pressure Distribution Manifold

1. The pressure distribution manifold shall be designed and sized to equally distribute flow to the each of the three absorption trenches of an absorption zone with a residual head of 2 feet at the absorption trenches.

The distribution manifold shall include a hydrosplitter model HSA200-03- 10 by Orenco Systems, Inc. The hydrosplitter shall have a single 2” manifold with three (3) 1” flexible PVC discharge hoses. The manifold shall include a ¾” diameter orifice plate located in each of three (3) 2” outlet unions before the 1” discharge hose. The orifice plate shall be Model FCDD200U750 by Orenco Systems, Inc. The manifold shall include three (3) 3” pipe adapters.

2. Hydrosplitter Materials of Construction

• Fittings: Schedule 40 PVC

• Unions: Schedule 80 PVC

• Flow control orifice disk: 1/8” thick schedule 80 PVC

• Flexible hose: PVC

• Pipe adapter: Schedule 4 PVC

H. Valve Vaults and Lids

1. Valve vaults shall be made of ribbed PVC pipe such as Perma-Loc brand as manufactured by Orenco Systems, Inc. Vaults shall include female treaded adapters for anchoring compatible access lid.

2. Lids shall provide a secure covering for access risers and shall be capable of supporting a 2,500 lb wheel load. Lids will be provided with polyurethane, neoprene, or EPDM gaskets to ensure a watertight seal.

Manufacturer shall supply with factory-installed insulation. Lids shall come with SS bolts for securing to vaults.

3. Vaults will be supplied with rubber grommets for creating watertight pipe penetrations. Grommets shall be secured to vaults with a single part adhesive such as ADH100 manufactured by Orenco Systems, Inc.

4. To ensure compatibility, one single manufacturer shall supply valve vaults, lids, pipe and conduit seals, and anchoring mechanisms.

I. Plastic Absorption Trench Chambers

1. The chambers shall be Model Quick 4 Equalizer 24 by Infiltrator Systems, Inc. The plastic chambers shall be arch shaped with an open bottom with provisions for effluent to exit the side of the chamber. The side exit openings shall be louvered so as not to allow entry of backfill materials.

The louver height shall be no less than 8.7 inches. The chambers shall achieve an axle loading of 16,000 lbs/axle (AASHTO rating of H-10) with 12” of compacted backfill. The chamber shall have end caps that accommodate 1.25” and 6” invert heights. The chambers shall be molded in units not exceeding 4.5 feet in length, by 1.3 feet in width, by 11 inches in height. The chamber’s total storage capacity shall be no less than 20 gal/chamber. The chamber’s total storage capacity shall be no less than 20 gal/chamber. The chamber shall be approved for onsite use in the state of

Oregon and shall meet the installation requirements for the State of Oregon. The chambers shall be manufactured of PolyTuff™ through a gas assisted injection molding process.

J. Septage Measurement Tools

1. Contractor shall provide a minimum of one scum measuring utility gauge.

The gauge shall consist of a minimum 3/8” diameter stainless steel rod with an incremental scale for measuring scum levels. The rod shall be bent at a 90-degree angle at the base to aid in identifying the scum “by feeling.”

The gauge shall be Model SMUG by Orenco Systems, Inc.

2. Contractor shall provide a minimum of one sludge measuring optical gauge. The body shall consist of 3/4” diameter Schedule 80 PVC with an incremental scale. The electronics shall consist of a 9-volt high intensity LED lamp encased in epoxy resin, a photosensor, and a 9-volt battery for power. The gauge shall be Model SMOG by Orenco Systems, Inc.

PART 3 – EXECUTION

3.1 INSPECTION

A. Inspect prefabricated and delivered systems and components to ensure they conform to approved submittals and plans prior to installation.

3.2 INSTALLATION

A. Septic Tank and Pump Tank

1. The tank installation is for non-traffic rating. The tanks shall be installed and tested in strict accordance with the manufacturers printed instructions for onsite wastewater applications in a non-traffic rated installation. The general layout and pipe locations are as indicated on the engineer’s plans.

If required by the tank manufacturer to retain warrantee, the tank installer shall be trained and or certified by the tank manufacturer in the installation of fiberglass underground storage tanks.

B. Tank Access Risers and Lids

1. Tank risers and appurtenances shall be installed per the riser manufacturer’s printed instructions. Tank access risers are to be bonded to the tanks with approved adhesive. Pipe grommets will be secured to the risers to provide a watertight pipe seal using approved adhesive. Risers and lids shall extend approximately 3 inches above the natural ground surface and grading around the risers shall facilitate drainage away from the tank openings.

C. Duplex Submersible Pumping System

1. All pumping system components shall be installed per the manufacturer’s printed instructions, the engineer’s plans, and state and local regulations.

2. Bundle excess pump power cable and float control cable and secure with cable ties below the splice box.

D. Duplex Pump Control Panel and Septic Tank Alarm

1. Control panel shall be mounted on two (2) 1 5/8” strut on a concrete base within 50 feet and in sight of the pump motor or the panel shall be provided with a lockable disconnect switch. The center panel height shall be approximately 5 feet above the ground.

E. Flow Meter, Zone Distribution Valve, Pressure Distribution Manifold and Valve Vaults

1. The flow meter, zone distribution valve and pressure distribution manifold shall be installed per the manufacturer’s printed instructions and the engineer’s plans.

2. The valve vaults shall be open bottomed and installed on approved bedding to allow for drainage. Vaults and lids shall extend approximately 3 inches above the natural ground surface and grading around the vaults shall facilitate drainage away from the vault openings.

3. Install a single layer of ½” to 1” hexagonal galvanized chicken wire mesh under valve vaults.

F. Plastic Absorption Trench Chambers

1. The plastic chambers shall be installed per the manufacturer’s printed instructions and the engineer’s plans.

2. Trench bottoms shall be level to within ±0.1 feet.

3. Install a single layer of ½” to 1” hexagonal galvanized chicken wire mesh on the bottom of the trench prior to placement of chambers to prevent rodent habitation of chambers.

4. Install an inspection port with threaded plug located in a plastic irrigation valve box at the end of each trench.

5. Include tracing wire over the top of each trench.

G. Pipe Connections

1. Comply with requirements for piping in Division 22 Section "Facility Sanitary Sewers” and the general layout and configuration of the engineer’s plans.

3.3 FIELD QUALITY CONTROLS

A. Tanks shall be tested according the manufacturer’s printed instructions.

B. Duplex Pumping System

1. Manufacturer’s Field Service: Engage a manufacturer approved service representative to inspect, test, and adjust components, assemblies, and equipment installations.

2. Perform visual inspection of systems.

3. Following installation fill the system with water.

4. After electricity has been energized, start pumps to confirm proper operation.

5. Test and adjust controls and safeties. Replace damaged and malfunctioning controls and equipment.

6. Pump and controls will be considered defective if they do not pass tests and inspections.

7. Manufacturer’s Startup and Demonstration Service: Engage a manufacturer approved service representative to start-up the pumping systems, adjust final control points and train the Government’s maintenance personnel to adjust, operate and maintain the controls and pumps.

C. Flow Meter and Zone Distribution Valve

1. With pump running visually inspect flow meter to ensure proper operation.

2. Cycle pump and visually inspect zone distribution valve clear pipe to ensure that the valve is cycling to alternating zones.

3. Flow meter and valve will be considered defective if they do not pass tests and inspections.