Likely sources of individual parameters

For a printable copy of this page see: Parameter-likely-sources-1.pdf (dwi.gov.uk)

Parameter 

Circumstances in which likely to be present

Acrylamide

Use of polyacrylamides as coagulant aids. Use of polyacrylamide grouts for borehole/well linings.

Aluminium 

Use of aluminium compounds as coagulants. Occurs in some surface and ground waters.

Antimony 

Possible from domestic plumbing fittings.

Arsenic 

Present in some ground waters.

Benzene 

Contamination of raw waters from petrol/diesel etc. Permeation of plastic distribution and domestic plumbing pipes.

Benzo(a)pyrene 

Leaching from internal coal tar lining of some distribution pipes.

Boron 

Contamination of surface waters with detergents mainly from sewage effluents.

Bromate 

Present in sodium hypochlorite used to disinfect water, including electrolytically generated hypochlorite. Formed if ozone used and water contains bromide.

Cadmium

Leaching from galvanised pipes and some domestic plumbing fittings (e.g. plated taps).

Chloride

Indicator of saline intrusion so relevant in coastal areas. Also relevant if water softener in situ. May indicate sewage pollution of surface water.

Chromium 

Leaching from some domestic plumbing fittings (e.g. chrome plated plastic taps).

Clostridium perfringens (including spores)

Contamination of raw waters from sewage effluents and animal waste.

Copper 

Leaching from pipes and plumbing fittings. Low pH and low or high alkalinity increases copper leaching.

Cyanide 

Possible contamination of raw waters from industry (e.g. metal finishing, wood preservatives).

1,2 dichloroethane 

Volatile solvent used in manufacture of vinyl chloride and other processes. Can contaminate and persist in ground water.

Enterococci 

Contamination of raw waters from sewage, sewage effluents and animal waste.

Epichlorohydrin 

Use of polyamines as coagulant aids. Use of epoxy resins (e.g. to line pipes and tanks). Use to make some ion exchange resins.

Fluoride 

May be present in some ground waters.

Iron

Use of iron compounds as coagulants. Occurs in some surface water and ground waters. Corrosion of iron distribution mains.

Lead 

Leaching from lead pipes in distribution and domestic plumbing or from lead soldered copper pipes. Low pH and low or high alkalinity increases lead leaching. Present naturally in some ground waters

Manganese 

Present in some greensand filtration materials. Occurs in some surface water and ground waters.

Mercury 

Contamination from mercury thermometers and float valves

Nickel

Leaching from some domestic plumbing fittings (e.g. plated taps).

Nitrate 

Contamination of surface and ground waters from fertilisers, animal wastes or sewage effluents.

Nitrite 

Contamination of raw waters. Use of chloramination as a residual disinfectant or use of chlorine as disinfectant when ammonium ions present.

Pesticides 

Contamination of raw waters from use in agriculture, forestry, roads, railways etc.

Pesticides – total 

This means the sum of the concentrations of the individual pesticides detected and quantified in the monitoring procedure.

Polycyclic aromatic hydrocarbons (PAH)

Leaching from internal coal tar lining of some distribution pipes. Sum of four individual PAH.

Selenium 

May occur naturally in some raw waters.

Sodium 

Present in raw waters but usually below standard. Can be introduced by water softeners and treatment chemicals (e.g. sodium hypochlorite for disinfection) or through saline intrusion of ground waters in coastal areas.

Sulphate 

Occurs in some raw waters, but usual below the standard.

Tetrachloroethene and Trichloroethene

Contamination of some ground waters from use of these volatile solvents in dry cleaning and metal finishing. Standard is sum of two compounds.

Tetrachloromethane 

Contamination of some ground waters from use of this volatile solvent in metal finishing and other industries.

Total indicative dose (for radioactivity)

Contamination of raw waters from natural or manmade radioactive compounds.

Trihalomethanes – total 

Formed by reaction of organic matter in raw water with chlorine compounds used as disinfectants. Standard is sum of four compounds.

Tritium 

Cosmic production in upper atmosphere. By-product of nuclear explosions and nuclear industry.

Vinyl chloride 

Used for making PVC. Leaching from unplasticised PVC pipes used in distribution or domestic plumbing.

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