Stage 1 Irrigation Area_90 Beach Rd Noosa North Shore 12.06.2020 · MCU19/0117

EFFLUENT IRRIGATION MANAGEMENT PLAN - STAGE 1
NOOSA NORTH SHORE ECO-TOURISM PORTAL

Cardno

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4.6

Element 1: Effluent Storage Lagoon

 

RATIONALE:

Uncontrolled discharge from the effluent storage lagoon may result in
impacts on soils, surface water and groundwater. Management
measures are required to prevent uncontrolled discharges.

 

OBJECTIVE:

To operate and manage the effluent storage lagoon to prevent
deterioration of receiving environments.

 

TASKS/
ACTIONS:

e The storage lagoon shall be constructed with a 600mm
impermeable clay lining to reduce the possibility of infiltration of
treated effluent to groundwater

e Stormwater diversion banks/drains shall be installed around the
effluent storage lagoon to exclude overland runoff from entering
the lagoon.

e The storage lagoon shall be operated and maintained to ensure
lagoon stability and prevent discharge through the bed or banks of
the lagoon.

e In the event that effluent levels within the lagoon rise within 1m of
the top level, super-irrigation of the effluent irrigation areas shall
be undertaken.

e Where super-irrigation is not possible due to wet weather or
soil conditions, the excess effluent shall be tankered to a
licenced effluent disposal facility.

e Where effluent quality within the lagoon is determined by
monitoring to be not in compliance with the specified release
limits, effluent shall be transported back to the STP for re-
treatment.

 

PERFORMANCE
INDICATORS:

Quality of effluent released from the effluent storage lagoon shall
comply with the following water quality objectives specified by EPA in
the Negotiated Decision Notice.

 

Parameter

Quality Criteria

Release Limit

 

Biochemical Oxygen
Demand (BOD)

20mg/L

maximum

 

Dissolved Oxygen (DO)

2.0mg/L

minimum

 

Suspended Solids (SS)

20mg/L

maximum

 

pH

6.5 — 8.5

range

 

Total Nitrogen (TN)

5mg/L

maximum

 

Total Phosphorous (TP)

Aimg/L

maximum

 

Free Residual chlorine

0.3 - 0.7mg/L

range

 

Faecal Coliforms (FC)

< 10 cfu/100mI
< 100 cfu/100ml

median
maximum

 

 

Turbidity

 

2 NTU

 

 

80" percentile

 

MONITORING:

 

 

Levels within the effluent storage lagoon shall be monitored on a
weekly basis.

The quality of effluent in the treated effluent storage dam shall be
monitored on a quarterly basis for pH, conductivity BOD, DO, SS, TN,
TP, FC, ammonia, nitrite and nitrate, turbidity and residual chlorine.

 

 

Petrac Leisure NNS-S Pty Ltd

1\7296-08\WP\technical reports\Effiuent Irrigation Management Plan - Stage 4 Version 2.doc

Version 2 17 July 2006

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