2019-21: Cobram (Victoria) – Vinyl Chloride, Iron

2019-20: Cobram (Victoria) Vinyl Chloride

p35 “All the volatile and semi volatile organic compounds tested in source water were reported by the NATA laboratory at values below the limit of detection with the exception of a single detection of Vinyl Chloride in the raw water above the health limit at Cobram and a single detection of diethyl thlalate detected at low levels in the raw water at Yea. Diethyl thlalate does not have a health-based limit within the ADWG. In light of the levels and subsequent downstream treatment processes, there was no risk to public health.” Goulburn Valley Water Water Quality Annual Report 2019-20

No safe concentration for vinyl chloride in drinking water can be confidently set. However,
for practical purposes, the concentration should be less than 0.0003 mg/L, which is the limit
of determination.

GENERAL DESCRIPTION
Vinyl chloride is used industrially in the production of poly vinyl chloride (PVC), which has wide
application in the plastics, rubber, paper and glass industries.
Vinyl chloride may be present in drinking water through pollution of water sources by chemical spills.
Water bottled and stored for long periods in PVC containers may contain very low concentrations of vinyl chloride. It has occasionally been detected in drinking water supplies that use PVC pipes in the United States and Germany, with a maximum reported concentration of 0.01 mg/L. In Australia there are stringent requirements on the maximum permissible residual vinyl chloride concentrations in PVC pipes and fittings.

TYPICAL VALUES IN AUSTRALIAN DRINKING WATER
Vinyl chloride has not been found in Australian drinking waters. It is included here to provide guidance in the unlikely event of contamination, and because it has been detected occasionally in drinking water supplies overseas.

Cobram (Vic) – Iron

2020/21: Cobram (Vic) – Iron 1.1mg/L (max)

Based on aesthetic considerations (precipitation of iron from solution and taste),
the concentration of iron in drinking water should not exceed 0.3 mg/L.
No health-based guideline value has been set for iron.

Iron has a taste threshold of about 0.3 mg/L in water, and becomes objectionable above 3 mg/L. High iron concentrations give water an undesirable rust-brown appearance and can cause staining of laundry and plumbing fittings, fouling of ion-exchange softeners, and blockages in irrigation systems. Growths of iron bacteria, which concentrate iron, may cause taste and odour problems and lead to pipe restrictions, blockages and corrosion. ADWG 2011