United States
Environmental Protection Office of Water EPA 81 1-F-94-007
Agency 4603 November 1994
FACT SHEET - SULFATE
This proposed rule is an innovative approach to regulating a naturally-occurring
drinking water contaminant. The approach EPA developed, working in cooperation
with several States at a 1992 meeting, was designed specifically to provide relief
to smaller systems in offering a means of compliance less expensive than central
treatment. Under this approach, the State would have the authority to allow public
water systems (PWSs), as one means of compliance with the sulfate MCL, to
provide alternative water and public education/notification to the targeted
population.
The proposed rule has been developed to ensure that sulfate levels in drinking
water are reduced below levels of concern by a unique means of compliance
tailored to the target population. The health effect from sulfate is temporary
diarrhea to those not accustomed to high levels of sulfate in drinking water. The
target populations consists of infants, travelers and new residents in areas with
high sulfate levels in water. This proposal is a combination of "alternative water"
and public notification/education, and affects all systems (community water
systems, transient non-community water systems, and non-transient, non-
community water systems). Most of the approximately 2,000 systems expected to
exceed the sulfate MCL serve populations of 3,300 people or less. "Alternative
water" is defined as either bottled water which has been monitored or certified to
be in compliance with all EPA MCLs, or water filtered by a point-of-use or point-of-
entry device.
The proposed Maximum Contaminant Level for sulfate is 500 mg/L. Central
treatment technologies effective in removing sulfate are reverse osmosis, ion
exchange and electrodialysis reversal.
Unique Means of Comoflanca
Four options are being proposed for public comment. The lead option requires
provision of alternative water to both transient adults (travelers and new residents)
and infants. Two variations of the lead option require provision of alternative water
to infants only. These two options differ only in the content of the public
notification. In one case, only infants are considered at risk, and temporary
diarrhea is considered as only an inconvenience for adults. In the other, both
-------
« "fants are considered at risk, but public notification is deemed sufficient
protect for adults. Because the lead option and its two variations represent a
significant change in regulatory approach, EPA considered another, more
conventional option. This fourth option would enable systems to seek a variance
from the sulfate MCL. As a condition of receiving a variance, systems would be
nnZ£ P'°T ! 'lternative water to *«" tarset populations, just as in the lead
th,n?nh ' V dlfference is tnat tne »«* for small systems would be provided
through a different statutory mechanism.
SUMMARY OF PROPOSED OPTIONS
Target
Population
._____
Alternative Water
provided
^»_
Public Notification/
Education
Adults &
Infants
Adults &
Infants
MMBMMMM
Yes
Infants
Infants
Yes
Adults &
Infants
Infants
i^M
Yes
Adults &
Infants
Adults &
Infants
"^IM^UBBM
Yes
Central
Treatment
Adults &
Infants
No
No
Community Water Systems (CWSs) adopting the lead option would be responsible
for providing alternative water on request to any household which has an infant or
travelers (guests), and to any household with new residents who have moved to
the community from outside the service area. For CWSs, there are four
components to the proposed public education and public notification requirement-
notices in bills, pamphlets, signs and notices to the media.
Transient systems, which comprise most of the affected systems (1,200 of 2 000)
and non-transient, non-community systems would be required to make alternative '
water available for travelers and new residents at establishments in the service
area. Where the target population is affected on a relatively continual basis
systems may find it more cost-effective to provide POU or POE devices Systems
which rarely serve the target population could choose to have a supply of bottled
water on hand. PWSs would be responsible for maintaining POU/POE devices to
ensure their continuing effectiveness. Public notification for transient systems and
non-transient, non-community systems would consist of permanent signs in places
such as rest areas, campgrounds, gas stations, etc. The signs would state the
nearest location of drinking water for individuals not acclimated to high sulfate
levels. If the-location has a POE device, posting would not be necessary since all
taps would provide water that complies with the MCL.
-------
Monitoring
Monitoring for sulfate would be one sample every three years for ground water
systems, and annual samples for surface water systems for systems with no
detections or which have BAT installed. A system with sulfate levels exceeding
the MCL which is authorized by the State to comply by implementing the unique
option being proposed would not be required to continue monitoring, since water in
compliance with the sulfate MCL would be provided to the target population.
COST OF THE PROPOSED OPTIONS
NATIONAL ANNUAL SULFATE COSTS FOR OPTIONS 1 - 4 ($ MILLIONS)
Central Treatment
Public Not. /Ed
Alternative Water
State Implementation
Monitoring
Total
OPTION 1 (LEAD)
$71»
(500 systems)
$7
(1,500 systems)
$7
$0.5
86
OPTIONS 2/3
.-
$8
$7
$0.5
$16
OPTION 4
(VARIANCE)**
$139
-
$7
$0.5
$147
* This total is for 25% of the 2,000 affected systems, which EPA estimates will
install central treatment, in spite of the availability of the less expensive, unique
alternative.
** Even though the variance provision is available, for costing purposes, this
option assumes 100% of systems comply by installing BAT.
Source: RIA for Surfate, August 31, 1994
For more information, contact the Safe Drinking Water Hotline, 1-800-426-4791.
-------
------- |