Protection of Aquifers - Hydrogeology: Objectives, Methods, Applications - page 194

These standards concern physical parameters, toxic and undesirable
substances, polycyclic aromatic hydrocarbons (PAHs), benzene toluene
ethylbenzene xylene (BTEX), volatile organic compounds (VOCs). They
do not yet take into account new contaminants (hormones, endocrine
disruptors, drugs).
Bacteriological analyses on water have a regulatory fi nality in terms
of respecting potable water standards. The regulatory sanitary analyses
focuse on a small number of bacteria, such as Escherichia coli , Enterococci,
and sulfur-reducing bacteria. The tests are concerned with common micro-
organisms, which serve as quality indicators. Their presence in excessive
amounts indicates the possibility that pathogenic organisms could also
survive in the same environment. These pathogens are looked for only
when a problem arises.
In the same way as chemical analyses, bacteriological analyses are done
at various points along the distribution network, from the resource all the
way to the consumer.

Table 20 Quality marker parameters, indicating the functioning of water production and
distribution systems.

Total aluminum 200 μg·L -1

Ammonium 0.1 mg·L -1

Total coliform bacteria 0 per 100 ml

Free and total chlorine no smell or taste

Copper 1 mg·L -1

Chlorites 0.2 mg·L -1

Chlorides 250 mg·L -1

Sulfur-reducing bacteria (including spores) 0 per 100 ml

Color 15 mg·L -1 (Pt/Co)

Conductivity 180 à 1,000 μS·cm -1 at 20°C

Concentration of hydrogen ions 6.5 à 9 pH units

Total organic carbon (TOC) 2 mg·L -1

Calco-carbonic equilibrium no aggressivity

Total iron 200 μg·L -1

Manganese 50 μg·L -1

Number of aerobic germs
revivable at 22 and 37°C

Can't exceed 10 times
the usual value

KMnO4 oxidability 5 mg·L -1 O2

Smell acceptable

Taste acceptable

Sodium 200 mg·L -1

Sulfates 250 mg·L -1

Temperature 25 °C

Turbidity 0.5 NFU