3.2.2 SSP2 STEP Tank
This section details the Septic Treatment and Effluent Pumping (STEP) tank serving Bungalows 1–16, designated as SPS2 (replacing the former SSP2 distribution box and lift well).
- Location: Opposite side of the causeway from SSP1, eastern end of Bungalow 16
Layout Diagram
Legacy System Decommissioned
The old SPS2 infrastructure — concrete distribution box, dual lift pumps, and 50 mm discharge pipe to SSP1 — has been decommissioned and replaced by this STEP tank.
Role in Collection Network
SPS2 serves Zone 2 of the collection network. Gravity sewer from Bungalows 1–16 discharges into this tank, which provides primary treatment and pumps primary clarified effluent to the WWTP.
Tank Specifications
| Item | Detail |
|---|---|
| Type | 22,000 L concrete tank with internal epoxy coating (H₂S attack prevention) |
| Manufacturer | Taylex Tanks (installed by Fastcall Plumbing NT) |
| Anti-flotation | Concrete ring-beam poured around base to prevent movement from seasonal groundwater |
| Lids | 2 × fibreglass lids with extended risers (Orenco) |
| Venting | Venting lid with activated carbon odour suppression kit |
| Access | Tank shield anti-access grate |
Access Lids
Two green Orenco / fibreglass access lids on the STEP tank risers. The fasteners differ — bring both a spanner and an Allen key.
| Lid | Fasteners | Open with |
|---|---|---|
| Lid 1 (Orenco SEWER marking) | Four hex-head bolts | Spanner / socket |
| Lid 2 | Four socket-head (Allen) bolts | Allen key |
Do Not Pry
Undo all bolts fully before lifting. Do not force or crowbar either lid while fasteners are still in.
Pump System
| Item | Detail |
|---|---|
| Pump Package | Orenco Biovault Pump Package (PVU72-2425-L) with Effluent Filter |
| Discharge Pumps | 2 × Orenco PF(50Hz)500712 — 3/4 hp, 50 gpm, 380–415 V, 50 Hz, 1-phase |
| Effluent Filter | Biotube 24" cartridge — prevents pump clogging from rags, wipes, and debris |
| Controller | Orenco MVP duplex panel — enclosure label A-MVP2-7-14 (MVP-DAX2DM dual-mode family); see Orenco Control Panel |
Only primary clarified effluent is discharged from this tank. Solids remain in the underground tank for passive anaerobic treatment. Desludging is required approximately every 6–8 years.
Meter Box (Electrical Enclosure)
Grey metal meter box on posts beside the STEP tank lids. This is the local enclosure for Pit 2.
| Item | Detail |
|---|---|
| Location | At the Pit 2 / SSP2 site (beside the green tank lids) |
| Contains | Circuit breakers feeding the control panel; Orenco SYSTEMS control panel; 10 A power point (G.P.O. OUTLET breaker) |
| Local breakers (labelled) | ALARM MOD, CONTROL, G.P.O. OUTLET (among others) |
| Panel | Orenco A-MVP2-7-14 (MVP duplex) — includes PUSH TO SILENCE ALARM; detail below |
| Warning light | Red light on top of the meter box — alarm / warning indicator |
| Communications | Internet-connected via 5.8 GHz Wi-Fi (client / bridge on the side arm of the meter box) |
| Upstream supply | Site feed / isolation for Pit 2 is also indicated at the green N.T. PIT-1 power switch box at SSP1 / Pit 1 (orange power-available lights and breakers for Pit 1 and Pit 2) |
Local vs Pit 1 Switch Box
The Pit 2 meter box holds the control panel, local breakers to that panel, and a 10 A GPO. The green box at Pit 1 is the shared power switchboard for Pit 1 and Pit 2 supply — not the Pit 2 controller.
Orenco Control Panel (Inside)
White Orenco enclosure with white door, mounted inside the Pit 2 meter box. Enclosure label: Orenco Systems®, Inc. — A-MVP2-7-14. This is an MVP duplex panel (dual-mode timed / demand dose family — commercially documented as MVP-DAX2DM style for two alternating pumps).
Identity and Ratings
| Item | Detail |
|---|---|
| Manufacturer | Orenco Systems®, Inc. |
| Enclosure / build label | A-MVP2-7-14 |
| Panel family | MVP Duplex — dual-mode (timed dose or on-demand); two alternating pumps |
| Commercial model family | MVP-DAX2DM (240 V duplex dual-mode) — AU/NZ site build |
| Logic module | Siemens LOGO! 230RCE — order no. 6ED1052-1FB08-0BA0 |
| Motor contactors | 2 × ABB AF09-30-10-13 (labelled 1 and 2) — product ID 1SBL137001R1310; coil 100–250 V AC/DC |
| HOA switches | Pump 1 and 2 — AUTO / OFF / HAND |
| Panel breakers (inside) | CONTROL, PUMP 1, PUMP 2 (20 A marked); lower rail MAIN SWITCH, PUMP CONTROL, 10 A OUTLET |
| Alarm silence | PUSH TO SILENCE ALARM on the outer Orenco door (meter-box view) |
| Communications | Ethernet into the LOGO! (LAN shown on LCD); site link via 5.8 GHz Wi-Fi on the meter box |
LCD Status (as photographed)
Default Orenco float / mode screen (matches MVP-DAX DM operation instructions):
| Line | Reading (2026-10-27 photo) |
|---|---|
| Float 5 | Down |
| Status 4 | Down |
| 3 | Down |
| Timed 2 | Up |
| Dose 1 | Up |
| Mode | Dose-OFF (timed-dose family) |
| Network | LAN |
Reading the Screen
Use the LOGO! arrow keys to move between Orenco alarm and data screens (pump cycles, run times, high/low alarms, power faults). Do not select Stop in the Siemens Setup menu — that can erase panel programming. Clock setup password (if needed) is documented by Orenco as LOGO.
Manuals and References
| Document | Link |
|---|---|
| Orenco MVP Duplex — technical data | NTD-CP-MVP-2 (PDF) |
| Orenco MVP-DAX DM — operation instructions | EIN-CP-OP-2496 (PDF) |
| Orenco MVP-DAX2 DM — wiring diagram | Wiring diagram (PDF) |
| Orenco MVP — time / date / contrast | EIN-CP-SET-111 (PDF) |
| Orenco MVP Duplex — product page | orenco.com |
| Siemens LOGO! system manual (covers 6ED1052-…-0BA0) | LOGO! System Manual (PDF) |
| Siemens LOGO! 230RCE datasheet | 6ED1052-1FB08-0BA0 |
| ABB AF09-30-10-13 | ABB product page · datasheet (PDF) |
Flow System
- Inflow: Gravity sewer from Bungalows 1–16 (DN150 common main via access chambers)
- Discharge: Primary clarified effluent pumped to WWTP Primary Tank 1 (PT-1)
Maintenance
SPS2-Specific Tasks (from O&M Manual Table 1)
| Task | Action | Frequency | Responsible |
|---|---|---|---|
| Check Biotube® Effluent Filters; clean as required | Inspect and clean 24" cartridge filter | Quarterly | ENVR |
| Check Biotube® Pump Vault Filters; clean as required | Inspect Biovault filter assembly | Quarterly | ENVR |
| Sludge accumulation assessment | Measure sludge and scum levels; organise de-sludge pump-out if required | Quarterly | ENVR |
See 3.2.15 O&M and Contingency for the full maintenance program.
Version Control
| Version | Date | Description |
|---|---|---|
| 1.0 | 2025-10-06 | Initial Release (legacy distribution box and lift well) |
| 2.0 | 2026-06-22 | Rewritten for STEP tank replacement per O&M Manual V1.1 |
| 2.0.1 | 2026-06-22 | Added STEP tank layout diagram |
| 2.1 | 2026-10-21 | Added Show on Map locate buttons |
| 2.2 | 2026-10-26 | Noted Pit 2 breakers / power indicators in green switch box at Pit 1 |
| 2.3 | 2026-10-27 | Current Pit 2 site photo as main location image |
| 2.4 | 2026-10-27 | Pit 2 meter box photo — local breakers, control panel, 10 A GPO |
| 2.5 | 2026-10-27 | Pit 2 meter box — red warning light on top |
| 2.6 | 2026-10-27 | Pit 2 meter box — internet via 5.8 GHz Wi-Fi |
| 2.7 | 2026-10-27 | Pit 2 meter box interior photo and labelled breakers |
| 2.8 | 2026-10-27 | Orenco A-MVP2-7-14 panel interior, LOGO!/ABB IDs, manuals |
| 2.9 | 2026-10-27 | STEP tank Orenco lid photo — spanner required for bolts |
| 2.10 | 2026-10-27 | Second STEP tank lid — Allen key required |
| 2.11 | 2026-10-30 | Hidden search aliases (pit 2 / SPS2 / SSP2) |
Next Review Date: 2027-04-27