For
PWS serving fewer than 10,000 people and use Surface Water or Ground Water
Under the Influence of Surface Water (GWUDI) as the source water
Web
Links:
http://www.epa.gov/safewater/mdbp/lt1eswtr_fact.html
http://www.epa.gov/fedrgstr/EPA-WATER/2002/January/Day-14/w409.htm
1.
Provisions
A.
Maximum
contaminant level goal (MCLG) for Cryptosporidium is zero
B.
Cryptosporidium minimum physical removal for filtered systems is 99%
(2-Log)
C.
Update watershed control programs for unfiltered systems
2.
Requirements: Monitor Filter Effluent Turbidity
A.
Filter Effluent Turbidity must be measured and recorded every 4 hours
B.
Conventional and direct filtration
1. ≤
0.3 NTU in at least 95% of measurements taken each month
2. Maximum turbidity level: 1 NTU
C.
Slow sand and diatomaceous earth (DE) filtration
1. 1
NTU in at least 95% of measurements taken each month
2. Maximum turbidity level: 5 NTU
D.
Alternative technologies
1. ≤
1 NTU in at least 95% of measurements taken each month
2. Maximum turbidity level: 5 NTU
