ENVIRONMENTAL FINAL GOVERNING STANDARDS ITALY

ITALY - 3 Drinking Water
system and during the month of warmest water temperature. Systems remain on the reduced schedule as
long as the average of all samples taken in the year is no more than 0.030 mg/L for TTHM and 0.045 mg/L
for HAA5. Systems that do not meet these levels must revert to routine (quarterly) monitoring the
following quarter.
6. A system is noncompliant if the annual average of all samples taken that year exceeds the TTHM MCL,
0.030 mg/L or the HAA5 MCL, 0.060 mg/L.
7. Sample must be taken at the point of maximum residence time in the distribution system and during the
month of warmest water temperature. If annual sample exceeds MCL (TTHM or HAA5) the system must
increase monitoring to one sample per treatment plant per quarter at the point of maximum residence time.
The system may return to routine monitoring if the annual average of quarterly samples is no more than
0.030 mg/L for TTHM and 0.045 mg/L for HAA5.
8. No reduced monitoring schedule is available. Noncompliance exists when the annual sample (or average of
annual samples is conducted) exceeds the TTHM MCL, 0.030 mg/L or if the HHA5 concentration exceeds
the MCL, 0.060 mg/L.
9. For TTHM and HAA5, a DoD system using only ground water NOT under the influence of surface water
that treats its water with a chemical disinfectant must collect the number of samples listed above. Samples
must be taken at a location in the distribution system reflecting the maximum residence time of water in the
system.
10. System may reduce monitoring to one sample per treatment plant per year if the system meets all of the
following conditions: a) the annual average for TTHM is no more than 0.030 mg/L; b) the annual average
for HAA5 is no more than 0.030 mg/L; and c) at least one year of routine monitoring has been completed.
Sample must be taken at the point of maximum residence time in the distribution system and during the
month of warmest water temperature. Systems remain on the reduced schedule as long as the average of all
samples taken in the year is no more than 0.030 mg/L for TTHM and 0.045 mg/L for HAA5. Systems that
do not meet these levels must revert to routine monitoring the following quarter.
11. Noncompliance exists when the annual average of quarterly averages of all samples, compounded
quarterly, exceeds the TTHM MCL, 0.030 mg/L or the HHA5 the MCL, 0.060 mg/L.
12. For TTHM and HAA5, a DoD system using only ground water NOT under the influence of surface water
that treats its water with a chemical disinfectant must collect the number of samples listed above. One
sample per treatment plant must be taken at a location in the distribution system reflecting the maximum
residence time of water in the system and during the month of warmest water temperature. If the sample
exceeds the MCL, the system must increase monitoring to quarterly.
13. System may reduce monitoring to one sample per three-year monitoring cycle if the system meets all the
following conditions: a) the annual average for TTHM is no more than 0.030 mg/L; b) the annual average
for HAA5 is no more than 0.030 mg/L; and c) at least one year of routine monitoring has been completed.
Sample must be taken at the point of maximum residence time in the distribution system and during the
month of warmest water temperature. Systems remain on the reduced schedule as long as the average of all
samples taken in the year is no more than 0.030 mg/L for TTHM, and 0.045 mg/L for HAA5. Systems that
do not meet these levels must revert to routine monitoring. Systems on increased monitoring may return to
routine monitoring if the annual average of quarterly samples does not exceed 0.030 mg/L for TTHM and
0.045 mg/L for HAA5.
14. Noncompliance exists when the annual sample (or average of annual samples) exceeds the TTHM MCL,
0.030 mg/L or the HHA5 the MCL, 0.060 mg/L.
15. For systems using chlorine dioxide for disinfection or oxidation, daily samples are taken for chlorite at the
entrance to the distribution system for chlorite. The monthly chlorite samples are collected within the
distribution system, as follows: one as close as possible to the first customer, one in a location
representative of average residence time, and one as close as possible to the end of the distribution system
(reflects maximum residence time within the distribution system).
16. Additional monitoring is required when a daily sample exceeds the chlorite MCL, 0.70 mg/L. A threesample
set (following the monthly sample set protocol) is required to be collected the following day.
Further distribution system monitoring will not be required in that month unless the chlorite concentration
at the entrance to the distribution system again exceeds the MCL, 0.70 mg/L.
17. For chlorite, systems may reduce routine distribution system monitoring from monthly to quarterly if the
chlorite concentration in all samples taken in the distribution system is below the MCL, 0.70 mg/L, for a
period of one year and the system has not been required to conduct any additional monitoring. Daily
samples must still be collected. Monthly sample set monitoring resumes when if any one daily sample
exceeds the MCL, 0.70 mg/L.
September 2012 Italy FGS 3-32
Revision 0