Fact Sheet: EPA Efforts to Control Microbial and Byproduct Risk (Jun '94)

United States Environmental
Protection Agency
Office of Water
(4603)
EPA 811/F-94-005
June 1994
&EPA
EPA EFFORTS TO CONTROL
MICROBIAL AND BYPRODUCT RISK
Three new rules [Disinfectants/Disinfection Byproducts Rule (D/DBPR) and Enhanced
Surface Water Treatment Rule (ESWTR) - proposal 6/94 and promulgation 12/96;
Information Collection Rule (ICR) - proposed 2/94 (59 FR 6332) and promulgation
10/94; dates are tentative] have been developed in a regulatory negotiation, with
participation from State and local health and regulatory agencies and elected
officials, consumer groups, environmental groups, and the drinking water industry.
The tentative implementation schedule is as follows:
EFFECTIVE DATES FOR ICR, D/DBPR. AND ESWTR
SYSTEM TYPE
Surface water
systems2
Ground water
systems2
POPULATION
SERVED
> 100, 000
10,000-99,999
<1 0,000
>1 0,000
<1 0,000
ICR1
micro
1/95
1/95
NA
NA
NA
DBP
1/95
NA
NA
1/95
NA
duration
1 8 mos.
1 2 mos.
NA
18 mos.3
NA
D/DBPR
Stage 1
6/98
6/98
6/00
6/00
1/02
Interim
ESWTR
6/98
6/98
NA
NA
NA
must be completed by 3/97. Also, some systems will be required to conduct studies (see below for details).
(2) - Surface water systems include those which use ground water under the direct influence of surface water.
Ground water systems are those which use only ground water not under the direct influence of surface water.
(3) - Limited requirements that will only apply to systems serving ^50,000 people.
Under these rules, the following contaminants and disinfectants will be regulated
for the first time: (ESWTR) - Cryptosporidium; (D/DBPR) - chloroform, bromoform,
bromodichloromethane, dibromochloromethane, dichloroacetic acid, trichloroacetic
acid, bromate, chlorite, chloral hydrate, chlorine, chloramines, and chlorine
dioxide. The rules will apply to community water systems and nontransient
noncommunity water systems. The ESWTR will also apply to transient noncommunity
water systems.

Information Collection Rule
The proposed ICR would require collection of occurrence and treatment data and
characterization for disinfectants, disinfection byproducts, and microorganisms
(including Giardia, Cryptosporidium, and viruses). Also, some surface water systems
serving > 100,000 and ground water systems serving > 50,000 must complete bench- or
pilot-scale studies of disinfection byproduct precursor removal by activated carbon
or membranes by 9/97. These data, in addition to concurrent health effects and
technology research, will be used to develop the ESWTR and Stage 2 of the D/DBPR.

Interim Enhanced Surface Water Treatment Rule
The proposed interim ESWTR will include options to be refined based on ICR
microbiological data. Generally, these include 1) requirements that surface water
systems with poorer quality source waters remove microbiological contaminants above
levels currently required by the SWTR of 99.9% for Giardia and 99.99% for viruses;
and 2) making no changes if the current SWTR is determined adequate. In addition,
systems will be subject to sanitary surveys and may be required to treat for
Cryptosporidium. A long-term ESWTR will be developed for systems serving <10,000
and may include revisions to the interim ESWTR for systems >10,000 (proposal 6/97,
promulgation 12/98).

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United States Environmental
Protection Agency
Office of Water
(4603)
EPA 811/F-94-005
June 1994
CFPA EPA EFFORTS TO CONTROL

wcrM MICROBIAL AND BYPRODUCT RISK

Three new rules [Disinfectants/Disinfection Byproducts Rule (D/DBPR) and Enhanced
Surface Water Treatment Rule (ESWTR) - proposal 6/94 and promulgation 12/96;
Information Collection Rule (ICR) - proposed 2/94 (59 FR 6332) and promulgation
10/94; dates are tentative] have been developed in a regulatory negotiation, with
participation from State and local health and regulatory agencies and elected
officials, consumer groups, environmental groups, and the drinking water industry.
The tentative implementation schedule is as follows:
EFFECTIVE DATES FOR ICR, D/DBPR, AND ESWTR
SYSTEM TYPE
Surface water
systems2
Ground water
systems2
POPULATION
SERVED
> 100,000
10,000-99,999
<1 0,000
>1 0,000
<1 0,000
ICR1
micro
1/95
1/95
NA
NA
NA
DBP
1/95
NA
NA
1/95
NA
duration
1 8 mos.
1 2 mos.
NA
18 mos.3
NA
D/DBPR
Stage 1
6/98
6/98
6/00
6/00
1/02
Interim
ESWTR
6/98
6/98
NA
NA
NA
- ICR monitoring, divided into microbiological occurrence and DBP occurrence, may begin when noted and
must be completed by 3/97. Also, some systems will be required to conduct studies (see below for details).
(2) - Surface water systems include those which use ground water under the direct influence of surface water.
Ground water systems are those which use only ground water not under the direct influence of surface water.
(3) - Limited requirements that will only apply to systems serving ^50,000 people.
Under these rules, the following contaminants and disinfectants will be regulated
for the first time: (ESWTR) - Cryptosporidium; (D/DBPR) - chloroform, bromoform,
bromodichloromethane, dibromochloromethane, dichloroacetic acid, trichloroacetic
acid, bromate, chlorite, chloral hydrate, chlorine, chloramines, and chlorine
dioxide. The rules will apply to community water systems and nontransient
noncommunity water systems. The ESWTR will also apply to transient noncorrununity
water systems.

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