2004/12 + 2016/21: Pine Creek (Northern Territory) – E.coli, Arsenic, Iodine, Radioactive

Pine Creek (Northern Territory)  E.coli

2006/07: Pine Creek E.coli 1 exceedance. 97.1% samples within guideline


Thermotolerant coliforms are a sub-group of coliforms that are able to grow at 44.5 ± 0.2°C. E. coli is the most common thermotolerant coliform present in faeces and is regarded as the most specific indicator of recent faecal contamination because generally it is not capable of growth in the environment. In contrast, some other thermotolerant coliforms (including strains of Klebsiella, Citrobacter and Enterobacter) are able to grow in the environment and their presence is not necessarily related to faecal contamination. While tests for thermotolerant coliforms can be simpler than for E. coli, E. coli is considered a superior indicator for detecting faecal contamination…” ADWG

Pine Creek (Northern Territory) – Arsenic

2002/05: Pine Creek Arsenic 0.006mg/L

2006/07: Pine Creek Arsenic 0.1mg/L

2009/10: Pine Creek Arsenic 0.0081mg/L

2008/9: Pine Creek  Arsenic 0.0082mg/L

2010/11: Pine Creek Arsenic 0.0077mg/L

2011/12: Pine Creek Arsenic 0.0077mg/L

2016/17: Pine Creek Arsenic 0.1mg/L

2020/21: Pine Creek Arsenic 0.05mg/L

2003/4: Natural arsenic has previously been identified in some bores in Pine Creek slightly above the Australian Drinking Water Guideline value. These bores have since been decommissioned from supply. The remaining bores are blended and mixed with surface water in order to produce water in accordance with the Australian Drinking Water Guidelines.

Arsenic issues are also a continuing problem in the Northern Territory. “Natural arsenic has previously been identified in some bores in Pine Creek slightly above the Australian Drinking Water Guideline value. These bores have since been decommissioned from supply.” Power and Water Corporation Water Quality Report 2004

“At Pine Creek, bore water continues to be blended with surface water to reduce the arsenic concentration in water supplied to customers. The average arsenic concentration in the blended water is less than the 2004 ADWG value of 0.007 mg/L, however the 95th percentile level is just above ADWG value at 0.008 mg/L” Power and Water Corporation Water Quality Report 2006 0.01mg/L arsenic recorded at Pine Creek 2006/7.

Arsenic: ADWG Guideline = 0.01mg/L Arsenic is bioaccumulative and symptoms may take 10-15 years to develop after expsoure at high levels. Drinking water can be contaminated with inorganic arsenic through wind blown dust, leaching or runoff from soil, rocks and
sediment. Groundwater sources such as bores will usually have higher arsenic levels than surface water. In major Australian reticulated water supplies concentrations of arsenic range up to 0.015mg/L, with typical values less than 0.005mg/L.

Pine Creek – (Northern Territory) – Iodine

2008/09: Pine Creek  Iodine 0.1mg/L

2009/10: Pine Creek Iodine 0.1mg/L

Iodide: Based on health considerations, the concentration of iodide in drinking water should
not exceed 0.5 mg/L.
Iodine: No guideline value has been set for molecular iodine.
The element iodine is present naturally in seawater, nitrate minerals and seaweed, mostly in the form of iodide salts. It may be present in water due to leaching from salt and mineral deposits. Iodide can be oxidised to molecular iodine with strong disinfectants such as chlorine.
Molecular iodine solutions are used as antiseptics and as sanitising agents in hospitals and laboratories.
Iodine is occasionally used for the emergency disinfection of water for field use but is not used for disinfecting larger drinking water supplies. Iodide is used in pharmaceutical and photographic materials. Iodine has a taste threshold in water of about 0.15 mg/L.
Iodide occurs in cows’ milk and seafood. Some countries add iodide to table salt to compensate for iodide-deficient diets.

Pine Creek – Radioactivity

2009/10: Pine Creek results are influenced by the result from a single sample which exceeded the gross alpha but not the gross beta activity level of 0.5 Bq/L. The reportable total annual radiation dose (95th percentile) for the Pine Creek water supply is below the maximum acceptable value of 1.0 mSv/year.