Jellyfish Compliance with SQIDEP · MCU15/0122

Australian Journal of Water Research
ISSN: 2203-9482 (Print) ISSN: 2203-9490 (Online)

The flow measuring device installed at the upstream sampling point consists of a high accuracy Control
Logic LMP307 pressure transducer with accuracy of 0.1% and a pipe insert Palmer-Bowlus flume (8
inch). The pressure transducer is mounted on the wall of the field inlet pit just upstream of the flume so
that depth measurements can be transformed to flow using the rating table associated with the flume.
The flume device and the pressure transducer operation were calibrated over a range of flow rates prior
to the commencement of the monitoring program.
Two ISCO 6712 automatic samplers with capacity to hold 24 samples are installed to collect runoff
samples from upstream and downstream sampling points as shown in Figure 3. The samplers are
housed in weatherproof security cabinets close to each sampling point. The suction hoses are kept as
short as possible to reduce head loss. Sampling stations are equipped with data loggers, battery and
solar chargers to ensure independent operation. The RIMCO RIM7499 tipping bucket rain gauge
installed to measure rainfall has a resolution of 0.2mm. The rain gauge is mounted on a three meter
pole as shown in Figure 3 to reduce the impact of the rain shadow created by any neighboring
buildings. A Bureau of Meteorology operated rain gauge is situated approximately 600m away from the
study site.
2.3 Sample Handling and Testing
A carefully formulated methodology was adopted for the selection of appropriate rainfall events for
evaluation, runoff sample collection and sample handling and testing. Only runoff samples originating
from rainfall events with a minimum of three antecedent dry days and more than 2.6mm rainfall depth
were tested. These rainfall events were classified as qualifying events. This was to ensure that there are
representative contributions from both driveways/parking lots and roof runoff as well as to ensure that
there was appreciable accumulation of pollutants on the impervious surfaces. The automatic samplers
were programmed to collect discrete samples.
The samplers were programmed to trigger based on the occurrence of rainfall. Sampling intervals were
programmed to vary based on the intensity of the rainfall received. Runoff samples collected from a
qualifying rainfall event are combined to form a composite sample (Event Mean Concentration –
EMC). Representative aliquots of samples were extracted using a churn sample splitter (Bel-Art
Products) and submitted to a NATA registered laboratory (Advanced Analytical Laboratory) for
analysis. The parameters tested and the test methods adopted are listed in Table 1. Sample collection,
handling and transport were undertaken in accordance with AS/NZS 5667.1:1998.


Table 1. List of Parameters and Test Methods
       Parameter                                  Method
       pH                                         APHA (2012) Method 4500
       Electrical conductivity                    APHA (2012) Method 2510B
       Total metals – Fe , Al, Mn , Cu, Cr,       US EPA 200.8/3050/6010B by ICPMS US
       Pb, Ni, Zn, Cd                             EPA (1994), US EPA (1996)
                                                  APHA (2012) Method 4500 by discrete
       Total nitrogen, NO3, TKN
                                                  analyser with persulphate digestion
       Total phosphorus, FRP                      APHA (2012) Method 4500 by discrete
       (orthophosphate P)                         analyser with persulphate digestion
       Total suspended solids (103oC)             APHA (2012) Method 2540 D
                                                  APHA (2012) Method 5310 by TOC
       Total organic carbon
                                                  analyser
       Total petroleum hydrocarbon (C10-
                                                  NEPM 2011 (draft)
       C40), silica gel




Australian Society for Commerce Industry & Engineering
www.scie.org.au
                                                                                                        4