Grassy (Tasmania) – Chloroketones
16/7/24: Grassy (Tasmania): 1,1,1-trichloropropan-2-one 2ug/L
Data are inadequate to set guideline values for chloroketones in drinking water.
GENERAL DESCRIPTION
The chloroketones are produced in drinking water as by-products of the reaction between naturally occurring organic matter and chlorine. No data are available on other sources or uses for these compounds. Concentrations of chloroketones in drinking water reported overseas are very low and are estimated at less than 0.01 mg/L.
TYPICAL VALUES IN AUSTRALIAN DRINKING WATER
In major Australian reticulated supplies 1,1,1-trichloropropanone has been recorded in concentrations up to 0.02 mg/L, but it is usually below the limit of determination of 0.0005 mg/L. No data are available for other chloroketones.
LIMITING FORMATION IN DRINKING WATER
The presence of chloroketones in drinking water can be minimised by removing naturally occurring organic matter from the source water, by reducing the amount of chlorine added, or by the use of alternative disinfectants.” 2011 ADWG
Grassy (Tasmania) – Haloacetonitriles
23/7/24: Grassy (Tasmania) – Dichloroacetonitrile 1.5ug/L
“GUIDELINE
Data are inadequate to set guideline values for haloacetonitriles in drinking water
GENERAL DESCRIPTION
Haloacetonitriles are formed from organic precursors during chlorination or chloramination of drinking water. Concentrations of dihaloacetonitriles reported overseas range up to 0.04 mg/L but are typically less than 0.003 mg/L. Concentrations of trichloroacetonitrile are less than 0.001 mg/L.
Trichloroacetonitrile has been used as an insecticide. No data are available on uses for the other haloacetonitriles.
TYPICAL VALUES IN AUSTRALIAN DRINKING WATER
No data are available on concentrations of haloacetonitriles in Australian drinking waters”. ADWG 2011
Grassy – Tasmania – Temperature
January 19 2016: Grassy (Tasmania) Ti Tree Drive – Temperature 20.4C
January 19 2016: Grassy (Tasmania) Sassafras St – Temperature 20.2C
January 19 2016: Grassy (Tasmania) Storage – Temperature 20.4C
GUIDELINE
“No guideline is set due to the impracticality of controlling water temperature.
Drinking water temperatures above 20°C may result in an increase in the number of
complaints.
Temperature is primarily an aesthetic criterion for drinking water. Generally, cool water is more palatable than warm or cold water. In general, consumers will react to a change in water temperature. Complaints are most frequent when the temperature suddenly increases.
The turbidity and colour of filtered water may be indirectly affected by temperature, as low water temperatures tend to decrease the efficiency of water treatment processes by, for instance, affecting floc formation rates and sedimentation efficiency.
Chemical reaction rates increase with temperature, and this can lead to greater corrosion of pipes and fittings in closed systems. Scale formation in hard waters will also be greater at higher temperatures…
Water temperatures in major Australian reticulated supplies range from 10°C to 30°C. In some long, above-ground pipelines, water temperatures up to 45°C may be experienced…
The effectiveness of chlorine as a disinfectant is influenced by the temperature of the water being dosed. Generally higher temperatures result in more effective disinfection at a particular chlorine dose, but this may be counterbalanced by a more rapid loss of chlorine to the atmosphere (AWWA 1990).