Licence conditions for pollution studies and reduction program


  

Licence conditions for pollution studies and reduction programs

Summary
 
Licence number: 10555
Title: Pollution Study: Short-term water quality sampling program
Start date: 09 Sep 2016
 
Licence Condition
The objective of this Pollution Study is to require the licensee to undertake a short-term water quality sampling program to characterise Picton STP’s effluent discharges to Stonequarry Creek and to obtain in-stream water quality sampling data to inform further discussions regarding the licensee’s proposal to alter the existing licensed precautionary discharge requirements and to increase the existing pollutant load limits.
The licensee must undertake effluent characterisation and in-stream water quality sampling during each of the three discharge regimes listed in the table below and in accordance with the following conditions:
* The EPA notes that the treated effluent may not be able to be discharged at exact percentages for proportion of creek flow.
The following conditions apply to Discharge Regime 1 listed in condition U1.2: i) Discharge Regime 1 is permitted to be undertaken for up to two weeks to enable sampling as specified under condition U1.6. ii) Sampling under Discharge Regime 1 must commence when flows in the creek fall below 8 ML/day.
It is the EPA’s preference that samples are collected when the creek flow is between 2.5 and 8 ML/day; however, sampling may occur in flows greater than 8 ML/day if rainfall occurs during the sampling period.
Sampling undertaken for Discharge Regimes 1 and 2 do not have to be undertaken in chronological order.
The licensee must collect samples from the following sample locations: i)  EPA Point 1 (outlet of the effluent buffer tank at the Western Dam); ii)  N911 – Stonequarry Creek at Picton Farm downstream of STP discharge point; iii)  N911A – Stonequarry Creek, upstream of STP discharge point, downstream of Redbank Creek; iv)  N914 – Redbank Creek, upstream of STP discharge point; v)  N912 – Stonequarry Creek, upstream of STP discharge point and Redbank Creek, downstream of Picton Township.
For each monitoring /discharge point specified below, the licensee must monitor (by sampling and obtaining results by analysis) the concentration of each analyte specified in Column 1. The licensee must use the sampling method and sample at the frequency specified:
EPA Point 1 - Effluent Discharge Characterisation
EPA Point 1 - Effluent discharge toxicity testing
Locations N911, N911A, N914 and N912 – In-stream water quality sampling
For the purposes of the tables above: a)  Special Frequency 3 means a total of 3 samples to be collected on different weekdays during the occurrence of each discharge regime specified in condition U1.2. b) Special Frequency 4 means a total of 7 samples to be collected on different weekdays during the occurrence of each discharge regime specified in condition U1.2.
The licensee must provide the EPA with the data results from the sampling program (in excel spreadsheet format) required by condition U1 and a copy of the original analysis report(s) from its appointed testing laboratory within 4 weeks of the completion of the sampling program.
At the same time as providing the EPA with the sampling data in condition U1.8, the licensee must provide a report to the EPA containing: i)  daily flow data from the discharge point (EPA Point 1) and licensed creek flow gauge (EPA Point 10) for all flow / discharge regimes and days when samples are collected; and ii)  a report on the operation and performance of the licensee’s reinstated creek flow gauge (EPA Point 10) and the use of the new flow rating curve, and a comparison with the flows recorded in the upstream NSW Office of Water flow gauge.