[Federal Register Volume 63, Number 77 (Wednesday, April 22, 1998)]
[Proposed Rules]
[Pages 20038-20047]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-10713]
[[Page 20037]]
_______________________________________________________________________
Part VI
Environmental Protection Agency
_______________________________________________________________________
40 CFR Parts 141 and 142
Maximum Contaminant Level Goals and National Primary Drinking Water
Regulations for Lead and Copper; Proposed Rule
Federal Register / Vol. 63, No. 77 / Wednesday, April 22, 1998 /
Proposed Rules
[[Page 20038]]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 141 and 142
[FRL-6001-4]
RIN-2040-AC27
Maximum Contaminant Level Goals and National Primary Drinking
Water Regulations for Lead and Copper
AGENCY: Environmental Protection Agency.
ACTION: Notice of data availability with request for comments.
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SUMMARY: On April 12, 1996, the Environmental Protection Agency (EPA)
published proposed minor revisions to the National Primary Drinking
Water Regulations (NPDWRS) for Lead and Copper (61 FR 16348). EPA is
providing additional information that the Agency is considering for
public review and comment. The Agency also is soliciting comment on
several additional options that EPA is considering for adoption into
the final regulatory revisions.
DATES: Written comments should be postmarked or delivered by hand by
June 22, 1998.
ADDRESSES: Send written comments to the Lead and Copper Rule Comment
Clerk, Water Docket (MC-4101), Environmental Protection Agency, 401 M
Street, SW, Washington, DC 20460. Please submit an original and three
copies of your comments and enclosures (including references). If you
wish to hand-deliver your comments, please call the Docket at (202)
260-3027 between 9 a.m. and 4 p.m., Monday through Friday, excluding
Federal holidays, to obtain the room number for the Docket. Please see
Supplementary Information under the heading ``Additional Information
for Commenters'' for detailed filing instructions, including electronic
submissions.
The record for this rulemaking has been established under docket
name National Primary Drinking Water Regulations for Lead and Copper.
The record includes supporting documentation as well as printed, paper
versions of electronic comments. The record is available for inspection
from 9 a.m. to 4 p.m., Monday through Friday, excluding legal holidays
at the Water Docket, 401 M Street, SW, Washington, DC 20460. For access
to the Docket materials, please call (202) 260-3027 to schedule an
appointment.
FOR FURTHER INFORMATION CONTACT: The Safe Drinking Water Hotline, toll
free 1-800-426-4791. The Safe Drinking Water Hotline is open Monday
through Friday, excluding Federal holidays, from 9 a.m. to 5:30 p.m.
Eastern Time. For technical inquiries, contact Judy Lebowich, Standards
and Risk Management Division, Office of Ground Water and Drinking
Water, EPA (MC-4607), 401 M Street SW, Washington, DC 20460; telephone
(202) 260-7595. Please see Supplementary Information under the heading
``Additional Data and Analyses'' for information on obtaining access to
the references cited in this Notice at EPA Regional Office locations.
SUPPLEMENTARY INFORMATION:
Regulated Entities
Entities potentially regulated by the Lead and Copper Minor
Revisions Rule are public water systems that are classified as either
community water systems (CWSs) or non-transient non-community water
systems (NTNCWSs). Regulated categories and entities include:
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Examples of regulated
Category entities
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Industry.................................. Privately-owned CWSs and
NTNCWSs.
State, Tribal, and Local Governments...... Publicly-owned CWSs and
NTNCWSs.
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This table is not intended to be exhaustive, but rather provides a
guide for readers regarding entities likely to be regulated by the Lead
and Copper Minor Revisions Rule. This table lists the types of entities
that EPA is now aware could potentially be regulated by the Lead and
Copper Minor Revisions Rule. Transient non-community water systems
(TNCWSs) may also be regulated by the Lead and Copper Rule in the
future depending on EPA's assessment of the data referenced in this
notice pertaining to the short-term health effects of lead in drinking
water at TNCWSs and the public comments received in response to today's
notice. Other types of entities not listed in the table could also be
regulated. To determine whether your facility is regulated by the Lead
and Copper Minor Revisions Rule, you should carefully examine the
applicability criteria in Secs. 141.3 and 141.80(a) of title 40 of the
Code of Federal Regulations. If you have questions regarding the
applicability of the Lead and Copper Minor Revisions Rule to a
particular entity, consult the person listed in the preceding FOR
FURTHER INFORMATION CONTACT section.
Additional Information for Commenters
To ensure that EPA can read, understand and therefore properly
respond to your comments, the Agency requests that commenters follow
the following format: Type or print comments in ink, and cite, where
possible, the paragraph(s) in this Notice to which each comment refers.
Please use a separate paragraph for each issue discussed and limit your
comments to the issues addressed in today's Notice.
If you want EPA to acknowledge receipt of your comments, enclose a
self-addressed, stamped envelope. No facsimiles (faxes) will be
accepted. Comments also may be submitted electronically to ow-
[email protected]. Electronic comments must be submitted as a
WordPerfect 5.1, WordPerfect 6.1, or ASCII file avoiding the use of
special characters and forms of encryption and must be transmitted by
midnight June 22, 1998. Electronic comments must be identified by the
docket name, number, or title of the Federal Register. Comments and
data also will be accepted on disks in WordPerfect 5.1, WordPerfect
6.1, or ASCII file format. Electronic comments on this notice may be
filed online at many Federal Depository Libraries.
List of Abbreviations Used in This Document
(b)(1) system--a small or medium-sized water system that is deemed
to have optimized corrosion control pursuant to 40 CFR 141.81(b)(1)
(b)(2) system--a water system that is deemed to have optimized
corrosion control pursuant to 40 CFR 141.81(b)(2)
(b)(3) system--a water system that is deemed to have optimized
corrosion control pursuant to 40 CFR 141.81(b)(3)
D/DBP--disinfectants and disinfection byproducts
LCR--Lead and Copper Rule
NPDWRs--National Primary Drinking Water Regulations
NTNCWS--non-transient non-community water system
OWQP--value or range for a water quality parameter that has been
designated by the State as representing optimal corrosion control
SDWIS--Safe Drinking Water Information System
TNCWS--transient non-community water system
WQP--water quality parameter
Table of Contents
A. Additional Data and Analyses
1. Exclusion of TNCWSs
2. Timing of Monitoring for Systems Subject to Reduced Lead and
Copper Tap Monitoring
B. Additional Regulatory Options EPA is Considering
1. Requirement that Systems Operate Optimal Corrosion Control
Treatment
[[Page 20039]]
2. Monitoring for WQPs after the Installation of Corrosion
Control Treatment
3. Notification of Residents of Buildings Served by Partially-
Replaced Lead Service Lines
4. State Reporting Requirements
(a) Clarify the Manner of Reporting
(b) Data to be Reported
C. Simultaneous Compliance Considerations: D/DBP Stage 1 Enhanced
Coagulation Requirements and the LCR
A. Additional Data and Analyses
On April 12, 1996, the Environmental Protection Agency (EPA)
published proposed minor revisions to the NPDWRs for Lead and Copper
(61 FR 16348). EPA is making available for public review and comment
additional data and analyses associated with two of the topics
discussed in that proposal: (1) The continued exclusion of TNCWSs from
coverage under the LCR; and (2) the requirement for water systems
subject to reduced monitoring under the rule to collect tap water
samples for lead and copper during the months of June through
September.
The new data and analyses are cited below. In addition to being
available for review by anyone in the LCR Docket, EPA has a limited
number of copies available to provide to requesters. A single set of
materials pertaining to each of the above topics may be ordered free-
of-charge, while supplies last, by calling the Safe Drinking Water
Hotline at 1-800-426-4791 and providing the following document
information.
EPA Publication #EPA 815-B-97-003. December 1997.
Information Pertaining to Lead in Drinking Water at Transient Non-
Community Water Systems. (This document contains all of the
materials cited below under the heading of Exclusion of TNCWSs.)
EPA Publication #EPA 815-B-97-004. December 1997. The
Effect of Temperature on Corrosion Control. (This document contains
all of the materials cited below under the heading of Timing of
Monitoring for Systems Subject to Reduced Lead and Copper Tap
Monitoring.)
These materials also are available for viewing at the following
Regional locations.
I. John F. Kennedy Federal Building, One Congress Street,
Boston, MA 02203-001. Contact: Ellie Kwong, Phone: (617) 565-3604.
II. 260 Broadway, New York, NY 10007-1866. Contact: Taj Khan, Phone:
(212) 637-3826.
III. 841 Chestnut Building, Philadelphia, PA 19107. Contact: Ed
Hotham, Phone: (215) 566-5778.
IV. AFC-Tower 9th Floor, 61 Forsyth Street, SW, Atlanta, GA 30303.
Contact: Region 4 Library, Phone: (404) 562-8190.
V. 77 West Jackson Boulevard, Chicago, IL 60604-3507. Contact:
Miguel Del Toral, Phone: (312) 886-5253.
VI. Fountain Place, 12th Floor, Suite 1200, 1445 Ross Avenue,
Dallas, TX 75202-2733. Contact: Dave Reazin, Phone: (214) 665-7501.
VII. 726 Minnesota Avenue, Kansas City, KS 66101. Contact: Elizabeth
Murtagh-Yaw, Phone: (913) 551-7440.
VIII. 999 18th Street Suite 500, Denver, CO 80202-2466. Contact:
Marty Swickard, Phone: (303) 312-7021.
IX. 75 Hawthorne Street, San Francisco, CA 94105. Contact: Roger
Yates, Phone: (415) 744-1843.
X. 1200 Sixth Avenue, Seattle, WA 98101. Contact: Region 10 Library,
Phone: (206) 553-1289.
1. Exclusion of TNCWSs
In the preamble to the April 12, 1996, proposal, EPA indicated that
the Agency was in the process of collecting additional data relevant to
the exclusion of TNCWSs from coverage under the LCR and that the Agency
would make that data available for public review and comment prior to
the promulgation of a final rule. EPA is providing the following
additional information pertaining to the short-term health effects of
lead and the likely occurrence of high levels of lead in drinking water
at TNCWSs for public review and comment in fulfillment of that
commitment. Based upon review of these documents, which are listed
below, the Agency continues to support the position articulated in the
proposed minor revisions (61 FR 16349 first column) that the exclusion
of this category of public water systems from coverage under the LCR
should be maintained. EPA solicits comment on whether the data cited
below should alter this position.
Agency for Toxic Substances and Disease Registry (ATSDR), 1992.
Toxicological Profile for Lead. U.S. Department of Health and Human
Services, Public Health Services, Atlanta, GA. TP-92/12. Pages 9,
65, 66, 98, and 99.
Giridhar, J. and Isom, G.E. 1990. Interaction of Lead Acetate with
Atrial Natriuretic Factor in Rats. Life Science, 46(8):569-576.
Hindmarsh, J.T. 1986. The Porphyrias: Recent Advances. Clinical
Chemistry, 32(7):1255-1263.
Karmakar, N., Saxena, R., and Anand, S. 1986. Histopathological
Changes Induced in Rat Tissues by Oral Intake of Lead Acetate.
Environmental Research, 41(1):23-28.
Khan, A.J., Patel, U., Rafeeq, M., Myerson, A., Kumar, K., and
Evans, H.E. January 1983. Reversible Acute Renal Failure in Lead
Poisoning. Journal of Pediatrics, 102(1):147-149.
Nakhoul, F., Kayne, L.E. Brautbar, N., Hu, N., McDonough, A.,
Eggena, P., Golub, M.S., Berger, M. Chang, C., Jamgotchian, N., and
Lee, D.B.N. 1992. Rapid Hypertensinogenic Effect of Lead: Studies in
Spontaneously Hypertensive Rat. Toxicol In. Health, 8(1-2):89-102.
U.S. Environmental Protection Agency. December 1995. A Survey Study
of Lead in Drinking Water Supplied by Transient Water Systems.
Prepared by R.P. Maas, S.C. Patch, D.M. Morgan, and G.M. Brown,
Environmental Quality Institute, The University of North Carolina at
Ashville. Technical Report # 95-019.
U.S. Environmental Protection Agency. March 20, 1996. Note from Jeff
Cohen to Judy Lebowich and Connie Bosma entitled: Analysis of UNC-
Ashville Survey of Lead at Transient Systems.
U.S. Environmental Protection Agency. November 3, 1997. Effects from
Short-Term Lead Exposure. Health and Ecological Criteria Division,
Office of Science and Technology, Office of Water.
EPA solicits public comment on these data as well as any additional
data relevant to the continued exclusion of transients from coverage
under the rule that commenters may wish to submit.
2. Timing of Monitoring for Systems Subject to Reduced Lead and Copper
Tap Monitoring.
In the April 12, 1996, notice, EPA proposed a revision to
Sec. 141.86(d)(4)(iv) that would allow seasonal NTNCWSs subject to
reduced monitoring that do not operate between the months of June and
September to collect lead and copper tap water samples during their
warmest months of operation. Several commenters suggested that all
water systems be allowed greater flexibility in the timing of
collection of lead and copper tap water samples on the basis that the
ambient outdoor temperature is not the only variable that may
significantly affect tap water levels of lead and copper. The Agency
agrees that it may be appropriate to provide such flexibility and is
providing for public review and comment the following documents which
present data and analyses pertaining to the effect of temperature on
lead and copper leaching.
Colling, J.H., Croll, B.T., Whincup, P.A.E., and Harward, C. June
1992. Plumbosolvency Effects and Control in Hard Waters. Journal
IWEM, 6(3):259-268.
Dodrill, D.M., and Edwards, M. July 1995. Corrosion Control on the
Basis of Utility Experience. Journal AWWA, 74-85.
Edwards, M., Schock, M.R., and Meyer, T.E. March 1996. Alkalinity,
pH, and Copper Corrosion By-Products Release. Journal AWWA, 81-94.
Rezania, L.W. and Anderl, W.H. 1996. Copper Corrosion and Iron
Removal Plants. Conference Paper. Section of Drinking Water
Protection, Minnesota Department of Health.
U.S. Environmental Protection Agency. An Evaluation of the Secondary
Effects of Enhanced Coagulation, With Emphasis on Corrosion Control.
Conference Paper prepared by D.A. Lytle, M.R. Schock, and R.J.
Miltner, Treatment and Technology
[[Page 20040]]
Evaluation Branch, Water Supply and Water Resources Division,
National Risk Management Research Laboratory.
U.S. Environmental Protection Agency. December 19, 1996. Memo from
Michael R. Schock, Treatment and Technology Branch, Water Supply and
Water Resources Division, National Risk Management Research
Laboratory, to Jeffrey B. Kempic of the Office of Ground Water and
Drinking Water, entitled: Seasonal Monitoring Revision. (Note:
References 5, 6, and 7 cited in the memo are not provided for public
review and comment. The Agency is not factoring the data contained
in these studies into its decision making.)
Wagner, I. June 18-22, 1988. Effects of Inhibitors on Corrosion Rate
and Metal Uptake. Proceedings of American Water Works Conference.
In light of the data presented in the documents cited above, the
Agency is considering allowing any water system subject to reduced
monitoring to collect lead and copper tap water samples during the
months of normal operation when lead levels are likely to be the
highest, or as otherwise designated by the State, instead of
prescribing the specific months during which reduced monitoring may
occur. EPA recognizes that it will be difficult in many cases to
predict beforehand whether a given water chemistry coupled with
physical factors will cause the highest values at a particular time.
There may be instances, however, where monitoring data from similar
systems or prior monitoring or survey experience at a particular system
is available that would suggest when the most appropriate monitoring
time(s) will occur. In the absence of such data, the Agency believes it
could still be appropriate to provide States and systems flexibility to
decide when to schedule sample collection within the monitoring period.
EPA recognizes that water systems already monitoring for lead and
copper at the tap on an annual or triennial frequency may feel locked
in to collecting samples during the months of June through September in
order either to avoid collecting samples sooner than they otherwise
would have to or to avoid a monitoring violation for not sampling on
time. For example, assume a water system is monitoring triennially and
last collected samples during the months of June through September
1997. If it were determined that it would be more appropriate for the
system to collect samples during the months of December through March,
it might be assumed that the system would need to collect the next
round of samples six months early (December 1999 through March 2000) in
order to avoid incurring a monitoring violation for not collecting the
next round of samples by September 2000.
This assumption, however, is not necessarily accurate. If this
option is promulgated, it is not the Agency's intent to force systems
already on a reduced monitoring schedule to continue to collect samples
during the summer months if some other sample collection time makes
more sense. In such cases, EPA believes it may be appropriate to give
States the discretion to determine the need for, and timing of, a
transitional monitoring period. For example, in the situation described
above, the State may determine that it would be better to extend the
schedule to March 2001 for that one round of monitoring. Such a
decision may be appropriate in those instances where the current
monitoring period would end before system could collect samples in the
new time frame and the State has determined, based on the system's
consistently low tap water lead and copper levels, that extending the
one monitoring period is unlikely to result in an increased risk to
public health.
EPA solicits public comment on these data, the appropriateness of
revising the requirements for the collection of samples under reduced
monitoring as discussed above, and whether there is a need for the rule
to explicitly provide States the flexibility to establish a
transitional monitoring period.
B. Additional Regulatory Options EPA is Considering
The Agency is soliciting public comment on two additional
regulatory options being considered in conjunction with requirements
pertaining to the maintenance of optimal corrosion control treatment, a
new regulatory option regarding notification of residents of buildings
served by lead service lines where only a portion of the service line
is to be replaced, and two additional regulatory options being
considered in conjunction with State reporting requirements. These
options are described below.
1. Requirement that Systems Operate Optimal Corrosion Control Treatment
Section 141.80(d) requires all water systems to install and operate
optimal corrosion control treatment. The method by which a system
demonstrates compliance with this requirement depends on its size and
the results of initial monitoring. The four basic pathways are
summarized below.
(1) A small or medium-size system may be deemed to have
optimized corrosion control if it can demonstrate for two
consecutive 6-month monitoring periods that it does not exceed
either the lead or the copper action level pursuant to
Sec. 141.81(b)(1). This demonstration can be made whether or not
treatment is actually physically present. Such systems demonstrate
ongoing compliance with the requirement to operate and maintain
optimal corrosion control through annual or once-every-three-year
(triennial) monitoring for lead and copper at the tap.
(2) A system may demonstrate to the State's satisfaction,
pursuant to Sec. 141.81(b)(2), that it has already completed
activities equivalent to the rule's corrosion control treatment
steps. The State must designate OWQPs for such a system which then
demonstrates compliance through routine WQP monitoring.1
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\1\ Note: EPA proposed on April 12, 1996, to clarify this
requirement for routine WQP monitoring.
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(3) A system may demonstrate to the State's satisfaction,
pursuant to Sec. 141.81(b)(3), that very little corrosion is
occurring in the distribution system.2 In some cases, a
system may be deemed to have optimized corrosion control even if no
corrosion control treatment is physically present. In other cases, a
system may be deemed to have optimized corrosion control if it had
previously installed corrosion control treatment prior to conducting
initial lead and copper tap monitoring. Currently, such systems are
not required to do any routine monitoring; however, EPA proposed on
April 12, 1996, to require these (b)(3) systems to monitor for lead
and copper at the tap no less frequently than triennially.
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\2\ Section 141.81(b)(3) does not currently include any
conditions pertaining to copper. EPA proposed on April 12, 1996, to
also require systems to meet the copper action level to be eligible
for the a (b)(3) exception of installing optimal corrosion control
treatment.
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(4) A system may complete the corrosion control treatment steps
specified in Sec. 141.81(d) for large systems or Sec. 141.81(e) for
small and medium-size systems. As a part of this process, the system
is required to install the optimal corrosion control treatment
designated by the State 3 and to complete two rounds of
follow-up monitoring. Unless the system meets the criteria of
Sec. 141.81(b)(1) based on the results of the follow-up monitoring,
the State then designates OWQPs; the system demonstrates it is
maintaining optimal corrosion control through routine monitoring of
these WQPs.
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\3\ In many cases, ``installation of optimal corrosion control
treatment'' will require the physical installation of a new
treatment process. In other cases, ``installation'' may be achieved
through adjustment to existing treatment process(es) already in
place. In a few instances, the State may determine that optimal
corrosion control already exists and that no further treatment
changes are necessary.
While EPA does not require the designation of OWQPs or routine WQP
monitoring for (b)(1) systems or for (b)(3) systems, the Agency
believes it is essential that the State requires these utilities to
implement appropriate process control mechanisms to assure proper and
consistent operation of any corrosion control treatment that is in
place at the time the system is deemed to be optimized that is or
subsequently
[[Page 20041]]
installed. These process control mechanisms may involve some WQP
monitoring but, in some instances, may be in the form of daily logs or
other information routinely provided to the State (or available to the
State upon request). The Agency believes it is more appropriate to give
States the flexibility to define the specific process control
requirements than to prescribe these requirements in a national
regulation, since most States routinely require certain treatment and
operational control verifications as a condition of a system's
operating permit.
EPA is concerned, however, that a (b)(1) system or a (b)(3) system
may misinterpret the absence of specific Federal process control
requirements as meaning that it has a license to ``turn off,'' or
depart from, optimal corrosion control treatment in the absence of
required monitoring under the LCR. EPA therefore is considering wording
changes to the introductory paragraph of Sec. 141.81(b) and to
Sec. 141.82(g) to clarify that all water systems are required to
operate and maintain optimal corrosion control even if there are no
specific Federal requirements for the system to monitor for WQPs.
Currently, the introductory paragraph of Sec. 141.81(b) reads:
A system is deemed to have optimized corrosion control and is
not required to complete the applicable corrosion control treatment
steps identified in this section if the system satisfies one of the
following criteria: * * *
EPA is considering revising it to read as follows:
A system is deemed to have optimized corrosion control and is
not required to complete the applicable corrosion control treatment
steps identified in this section if the system satisfies one of the
criteria specified in paragraphs (b)(1) through (b)(3) of this
section. All systems deemed to have optimized corrosion control
under this paragraph shall continue to operate and maintain any
optimal corrosion control treatment in place at the time the system
is deemed to have optimized corrosion control and any requirements
that the State determines appropriate to ensure such treatment is
maintained.
The first sentence of Sec. 141.82(g) currently reads:
All systems shall maintain water quality parameter values at or
above minimum values or within ranges designated by the State under
paragraph (f) of this section in each sample collected under
Sec. 141.87(d).
It would be revised to read as follows:
All systems optimizing corrosion control under this subpart
shall continue to operate and maintain any such treatment, including
maintaining water quality parameters at or above minimum values or
within ranges designated by the State under paragraph (f) of this
section, in each sample collected under Sec. 141.87(d).
These wording revisions do not add any new requirements; rather
they clarify EPA's original intent that systems deemed to have
optimized corrosion control continue to maintain any treatment in place
to ensure that lead and copper levels remain minimal. The Agency does
not believe there will be any change in regulatory burden as a result
of this clarification.
EPA solicits public comment on this clarification.
2. Monitoring for WQPs After the Installation of Corrosion Control
Treatment
Water systems subject to routine WQP monitoring requirements must
collect WQP samples at each entry point to the distribution system once
every two weeks (biweekly). Although EPA did not request public comment
on the issue of compliance with OWQPs, several commenters expressed
concern that the current approach for determining water system
compliance with OWQPs could trigger inappropriate violations and
recommended that EPA change the approach. After reviewing these
comments, EPA is considering a regulatory change to modify the
definition of what constitutes a WQP violation.
Under the current regulation, any system that has an excursion from
the State-designated OWQP range is allowed to take a confirmation
sample within three days. Section 141.82(g) defines an OWQP violation
as follows:
* * * If the water quality parameter value of any sample is
below the minimum value or outside the range designated by the
State, then the system is out of compliance with this paragraph. As
specified in Sec. 141.87(d), the system may take a confirmation
sample for any water quality parameter value no later than 3 days
after the first sample. If a confirmation sample is taken, the
result must be averaged with the first sampling result and the
average must be used for any compliance determinations under this
paragraph. States have discretion to delete results of obvious
sampling errors from this calculation.
Some systems, especially large surface water systems, conduct WQP
monitoring more frequently than required by the LCR in order to
maintain effective process control. Because Sec. 141.87(f) requires
that these ``diagnostic'' monitoring results also be considered,
Sec. 141.87(f) can complicate OWQP compliance determinations. Section
141.87(f) reads as follows:
Additional monitoring by systems. The results of any monitoring
conducted in addition to the minimum requirements of this section
shall be considered by the system and the State in making any
determinations (i.e., determining concentrations of water quality
parameters) under this section or Sec. 141.82.
Since Sec. 141.82 describes OWQP compliance, any ``diagnostic''
monitoring results also must be factored into the compliance
determination.
The current regulatory language requires that even a minor
excursion from the State-designated OWQPs be identified as a violation,
even when it may not reflect a problem in the operation of treatment or
be of any public health concern. Rather than assigning a violation to a
situation which may not be a public health concern, EPA is considering
modifying the confirmation sample approach in the existing rule by
eliminating the language in Secs. 141.82(g) and 141.87(d) on
confirmation samples and replacing it with a provision allowing a
repeat sample that would need to be taken within three days. Instead of
basing compliance on the average of the original and confirmation
samples, compliance would be determined based solely on the results of
the repeat sample, if one is collected, or on the results of the first
sample if a repeat sample is not collected. This would preclude an
attempt by a system to overcompensate with a treatment correction (that
might adversely impact other treatment processes) just to ensure that
the average of the two samples would be within an acceptable range.
The revised regulatory provisions EPA is considering also provide
better process control than the current regulation. EPA is concerned
that the averaging approach in the current rule could allow systems
that are not adequately controlling some WQPs to remain in compliance.
The following example illustrates the concern. A State sets a WQP pH
range of 7.3-7.8 for a system that uses a caustic feed pump at the
wellhead or at the end of a water plant feeding into the system. If the
pump is not well controlled, it is possible that the pH can be 6.9 one
day and 8.4 three days later when the confirmation sample is taken.
Under the procedure in the current rule, the average (7.65) is within
the range, but adequate process control is not being maintained.
Variability in pH values can commonly occur with lime feed treatment at
many small and some medium-sized treatment plants. The goal of OWQP
monitoring is to ensure good process control. The current approach,
however, has the potential to reward poor process control, as seen in
this example.
[[Page 20042]]
Under the new option EPA is considering, the third and fourth
sentences in Sec. 141.82(g) would be revised to read as follows:
As specified in Sec. 141.87(d), the system may take a repeat
sample for any water quality parameter value no later than 3 days
after the first sample. If a repeat sample is taken, compliance
determination under this paragraph will be based solely on the
results of the repeat sample; if a repeat sample is not taken,
compliance determination under this paragraph will be based on the
results of the first sample.
The third and fourth sentences in Sec. 141.87(d) would be revised
to read as follows:
The system may take a repeat sample for any water quality
parameter value no later than 3 days after the first sample. If a
repeat sample is taken, any compliance determination under
Sec. 141.82(g) must be based solely on the results of the repeat
sample; if a repeat sample is not taken, the result of the first
sample must be used for an compliance determination under
Sec. 141.82(g).
This approach parallels the repeat sampling approach in the Total
Coliform Rule and is one of the reasons for changing the terminology
from ``confirmation samples'' to ``repeat samples.'' Another reason for
changing the terminology is to avoid confusion with confirmation
samples under the NPDWRs for organic and inorganic chemicals where
averaging of results is still required.
EPA does not believe that it is necessary to change Sec. 141.87(f)
as a part of this option. That is, systems and States would continue to
be required to factor the results of any monitoring conducted in
addition to the minimum requirements of Sec. 141.87 into the compliance
determination.
There is no increase in burden to implement this option since both
the current rule and this option allow a second sample to be taken.
This option would only change how the results from the second sample
are used to determine compliance.
EPA solicits public comment on this new approach.
3. Notification of Residents of Buildings Served by Partially-Replaced
Lead Service Lines
In the April 12, 1996, notice, EPA proposed changes to the rule's
lead service line replacement requirements at Sec. 141.84(d). While
some provisions within Sec. 141.84(d) pertaining to partial lead
service line replacement were proposed to be changed, no revision was
proposed to the notification requirements associated with partial lead
service line replacement. As proposed, Sec. 141.84(d) contains the
following requirements:
* * * In cases where the system does not replace the entire lead
service line, the system shall notify the user served by the line
that the system will replace the portion of the service line [that
is under the system's control] and shall offer to replace the
building owner's portion of the line, but is not required to bear
the cost of replacing the building owner's portion of the line. For
buildings where only a portion of the lead service line is replaced,
the water system shall inform the resident(s) that the system will
collect a first flush tap water sample after partial replacement of
the service line is completed if the resident(s) so desire. In cases
where the resident(s) accept the offer, the system shall collect the
sample and report the results to the resident(s) within 14 days
following partial lead service line replacement.
Upon further consideration, EPA believes that this language is
somewhat ambiguous as to who is to be notified in those instances where
the property owner and the resident are not the same (e.g., apartment
buildings). The Agency also believes the requirement to take a follow-
up sample upon resident request could place an undue burden on the
water system in those instances where a line serves a large multifamily
residence because the system could be required to take numerous follow-
up samples. EPA does not believe that a large number of samples is
required to determine the immediate effect of the partial replacement.
Finally, EPA is concerned that the time frame specified for the sample
collection and reporting of the results may not provide an adequate
level of public health protection.
In order to address these concerns, EPA is considering the
following revision to Sec. 141.84(d).
(1) Replacing the word ``user'' in the first sentence of the
requirement cited above with the word ``owner'' to clarify that the
offer to replace the privately-owned portion of the line should be made
to the property owner.
(2) Adding a requirement that the water system provide a notice to
the resident(s) of the building(s) served by the line at least 45 days
before commencing with partial lead service line replacement. The
purpose of such notice would be to inform the actual consumer(s) of the
tap water affected by the lead service line that they may experience a
temporary increase of lead levels in their drinking water due to
material disturbances in the construction process and to provide them
with guidance about the measures they can take to minimize their
exposure to lead. The Agency feels that 45 days is a sufficient amount
of time for the recipients to study the guidance provided by the water
supplier, to familiarize themselves with the potential ramifications
associated with the partial lead service line replacement, and to plan
and implement appropriate measures to avoid exposure to lead.
(3) Replacing the requirement for a resident-requested follow-up
sample within 14 days of completing the partial replacement with the
following requirement:
* * * The water system shall inform the resident(s) that the
system will collect one tap water sample representative of the water
in the service line for analysis of lead content as prescribed under
Sec. 141.86(b)(3) within 24 hours after the completion of the
partial replacement of the service line. The system shall collect
the sample and report the results of the analysis to the owner and
the resident(s) served by the line within three days of receiving
the results.
The Agency feels that the affected parties should be provided with
the test results as quickly as possible so they can implement
appropriate measures commensurate with the findings as soon as they can
to minimize their exposure. In addition, unnecessary expenses and
further concerns will be alleviated in those instances where the
analytical results indicate no increase in lead levels resulting from
the partial replacement.
(4) Adding the following provision to provide for some flexibility
in the method of delivery of the required notification(s):
The water system shall provide the required information to the
residents of individual dwellings by mail or by other methods
approved by the State. In instances where multifamily dwellings are
served by the line, the water supplier shall have the option to post
the information at a conspicuous location.
In order to facilitate State determination of compliance with the
requirement to collect a follow-up sample after partial replacement of
a lead service line, EPA believes it is appropriate that the results
from the follow-up sample also be reported to the State, in addition to
being maintained in the system's files as required by Sec. 141.91. The
Agency does not believe that it is essential that the results be
provided to the State within three days of receiving the results,
however. Instead, EPA is considering an option that would require the
water system to provide the results to the State within the first ten
days of the month following the month in which the system receives the
results. In this way, the reporting of the results to the State can be
combined with other regularly submitted data to
[[Page 20043]]
the State so that any increased burden associated with this additional
system reporting requirement is kept to a minimum. If the Agency
decides to add this reporting requirement, it will be codified as a new
Sec. 141.90(e)(4).4
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\4\ On April 12, 1996, EPA proposed to delete the existing
Sec. 141.90(e)(4) since it would no longer be relevant if the rule
is revised to remove the rebutable presumption that the water system
controls the entire length of the service line.
---------------------------------------------------------------------------
EPA requests public comment on the above provisions pertaining to
notification associated with partial lead service line replacement,
including comments on potential burden implications.
4. State Reporting Requirements
EPA is considering and requests public comment on the following two
revisions affecting State reporting of data to EPA.
(a) Clarify the Manner of Reporting
Paragraphs (a) and (b) of Sec. 142.15 explicitly provide authority
to the Administrator of EPA to specify the format of reporting for
violation, follow-up actions, and inventory data. Section 142.15(c)(4),
which defines 90th percentile and milestone reporting for the LCR, is
silent concerning the format of that reporting. As a result, some
States have questioned whether EPA has the authority to require that
the LCR 90th percentile and milestone data be reported in a prescribed
format. EPA requests public comment on whether the Agency should
clarify in the introductory text of Sec. 142.15(c)(4), that ``States
shall report to EPA by * * *, in a format prescribed by the
Administrator, the following information * * *.''
(b) Data to be Reported
In light of the comments received on State reporting requirements
and careful internal deliberations, EPA is considering restructuring
the State reporting requirements for the LCR. EPA has been guided by
several principles during these deliberations and has sought to achieve
a balance between the information required to oversee rule
implementation and the need to reduce the reporting burden to the
maximum extent possible without jeopardizing public health or
protection of the environment. EPA is considering an option that would
reduce the number of milestones that States would be required to report
to the Agency. This option would in no way change the information the
States are required to keep in State files or data systems--only the
information which would be reported on a regular basis to EPA. A more
complete explanation of EPA's rationale and guiding principles follows.
First, implementation of the LCR is, and will remain, a high
priority for the EPA due to the significant health effects of lead,
especially on children. The State reporting requirements reflect this
priority in that they go beyond requirements for other drinking water
regulations (that is, beyond reporting violation and follow-up actions
to the Agency). In addition, as noted above, the State record keeping
requirements would not be changed by this revision. EPA expects States
to maintain the required information in their files. EPA intends to
periodically audit these files as part of its review of State
performance. EPA may ask States in the future to provide the Agency
additional detailed information on implementation of the LCR, for
example, a one-time report on systems for which the State has
designated OWQPs or maximum permissible source water levels. EPA
believes that this approach will be less burdensome overall to the
States, yet will provide the Agency the information it needs to oversee
implementation of this priority rule.
Second, EPA has sought to simplify the reporting requirements. The
LCR is one of the most complex drinking water regulations. The rule's
implementation period may be as long as 25 years from the time the
Agency promulgated the rule for systems which are triggered into lead
service line replacement requirements. Compliance with many key
treatment technique requirements is based on the system meeting
prescribed milestones, with several years potentially elapsing between
milestones. Moreover, States have significant discretion in the
determination of system-specific requirements such as what constitutes
optimal corrosion control. Finally, a system may be in compliance with
the rule's requirements, yet still have high levels of lead or copper
at the tap.
As a result of these complexities, EPA imposed State reporting
requirements that were intended to provide information on compliance
with all of the interim milestones in order to oversee rule
implementation, to respond to inquiries from the public and others, and
to target compliance assistance and enforcement efforts. EPA believes
these activities still must be accomplished for this priority rule,
however, the Agency is seeking to simplify the State reporting
requirements, while retaining sufficient information in the national
data base to provide a degree of oversight and to answer some basic
questions. Some have suggested that EPA eliminate all milestone
reporting. EPA disagrees with the appropriateness of doing so. Due
primarily to the structure and requirements of the rule, EPA believes
strongly that the Agency continues to need more information about the
status of LCR implementation than can be derived simply from violation
and follow-up action data.
Therefore, EPA is considering an option that would eliminate the
requirement for States to report completion of several of the interim
milestones but would provide better information than the currently
required milestone reporting for a few key activities. Under this new
option, States would be required to report the following key elements.
(1) The 90th percentile lead values for all PWSs that exceed the
lead action level, the 90th percentile lead values (even where the
lead action level is not exceeded) for all large and medium-size
systems, and the 90th percentile copper values for all PWSs that
exceed the copper action level. Note that it is a data sharing
``goal'' for States to provide the 90th percentile lead values below
the action level for small systems as well. EPA is not planning to
require reporting of these values at this time due to the burden of
reporting that data for the very large number of small systems.
(2) A ``deemed'' milestone indicating that the system has
optimized corrosion control along with an indication of the basis
upon which that determination was made (e.g., the system is deemed
to be optimized pursuant to Sec. 141,81 (b)(1), (b)(2), or (b)(3),
the system is optimized as a result of installing corrosion control
treatment, or the system is optimized on the basis of adjusting
existing treatment).
(3) Systems required to replace lead service lines.
(4) A ``done'' milestone that indicates that the system has
completed all applicable corrosion control, source water treatment
and lead service line replacement requirements. Note that for many
systems it may be possible to report this milestone at the same time
as the ``deemed'' milestone.
This information, along with the quarterly violation and follow-up
information, will provide EPA data on the status of rule implementation
and will allow targeting of compliance and enforcement activities based
on the violations which are reported. As noted above, additional
information may be obtained through audits of State files or, if the
need arises, through special one-time reports.
Given the deletion of many of the milestone reporting requirements,
it will be critical that States report this more limited set of
information completely and in a timely manner. EPA will be following up
with States to ensure that this is occurring.
Table 1 compares the current State reporting requirements, the
revisions
[[Page 20044]]
proposed on April 12, 1996, and the new option EPA is considering. The
table also provides a brief explanation of the Agency's rationale for
the new option.
Table 1.--Comparison of Options Under Consideration for State Reporting Requirements Under the Lead and Copper
Rule
----------------------------------------------------------------------------------------------------------------
Current
Requirement requirement 4/12/96 proposal New option Rationale
----------------------------------------------------------------------------------------------------------------
Frequency of reporting for Quarterly........ Requested comment Retain quarterly 90th percentile data
milestone & exceedance data. on reducing the reporting. used as part of
frequency to determining
semi-annual or significant non-
annual but did compliers (SNC) which
not propose any needs to be done
changes. quarterly to ensure
timely & appropriate
follow-up action.
90th percentile lead values.... Required for all Require for all Require as Used in calculation of
lead action lead AL proposed; make SNC for some
level (AL) exceedances and reporting of violations; needed to
exceedances; for large/medium values <= lead support environmental
requested via systems <= lead AL for small indicators and to
guidance for all AL. systems a data demonstrate
large/medium sharing goal. effectiveness of
systems <= lead corrosion control
AL and for any treatment; data
small system frequently requested
that has by the public.
exceeded the
lead AL at some
time in the past.
90th percentile copper values.. Required for all Retain current Retain current Needed to support
copper AL requirement. requirement make environmental
exceedances. reporting of indicators and to
values <= copper provide national view
AL a data of occurrences of
sharing goal. high copper levels at
the tap.
Systems required to conduct Required......... Eliminate........ Eliminate........ See Note 1.
corrosion control study [CCSR].
Systems that have completed Required......... Eliminate........ Eliminate........ See Note 2.
corrosion control study [CCSC].
State designation of optimal Required......... Retain........... Eliminate........ See Note 1.
corrosion control treatment
(OCCT) to be installed [OTDE].
State designation of source Required......... Retain........... Eliminate........ See Note 1.
water treatment (SOWT) to be
installed [STDE].
Systems that have installed Required......... Eliminate........ Redefine to Even though States are
OCCT [OTIN]. indicate that required to report a
system is violation if the
optimized and system fails to
the basis for install the corrosion
considering it control treatment
optimized. designated by the
Require State, this milestone
reporting for provides fundamental
all systems. information on status
of LCR
implementation. In
addition to
indicating that
system has installed
corrosion control
treatment, where
required, it provides
data on the basis by
which other systems
are considered to be
optimized. This
information is not
readily available
through other
mechanisms.
Systems that have installed Required......... Retain........... Eliminate........ See Note 2. If EPA
source water treatment [SOWT]. needs to know how
many systems
installed source
water treatment
specifically to meet
LCR requirements,
this information
could be requested
through a one-time
report.
Systems for which State has Required......... Retain........... Eliminate........ See Note 1.
designated water quality (WQP)
ranges [WQPS].
[[Page 20045]]
Systems for which State has Required......... Eliminate........ Eliminate........ See Note 1.
designated maximum permissible
source water levels (MPLs)
[MPLS].
Systems required to replace Required. Must Revise to Revise to Basic milestone
lead service lines [LSLR]. also report any eliminate eliminate provides fundamental
accelerated lead information information information about LCR
service line about about implementation
replacement accelerated accelerated status. Without this
schedule and schedule and schedule and milestone, there is
annual annual annual no other way to
compliance. compliance. compliance. readily determine
which systems are
required to do lead
service line
replacement.
If system fails to
meet an accelerated
replacement schedule,
the State is required
to report a
violation. If EPA
needs to know that a
system in violation
of the lead service
line replacement
requirement is on an
accelerated schedule,
this information can
be provided by the
State on a case-
specific basis. Data
about annual
compliance also
redundant reporting
since violation
reporting required
for systems failing
to meet this
milestone.
Systems that have completed all None............. None............. Add Require Provides fundamental
CCT, SOWT, and LSLR reporting for information on status
requirements. all systems. of LCR
implementation.
WQP ranges designated by State None............. Comments Do not require... Ranges by themselves
as representing optimal requested but no not meaningful unless
corrosion control. requirement also have significant
proposed. other system-specific
data.
MPLs designated by State as None............. Comments Do not require... Levels by themselves
meeting source water treatment requested but no not meaningful unless
objectives. requirement also have significant
proposed. other system-specific
data.
----------------------------------------------------------------------------------------------------------------
Notes:
1. State determination/decision. EPA need for this milestone is to ensure that States are making timely
decisions; this need can be met through other mechanisms such as program evaluations and periodic data
verifications, etc. As defined, there is no way to accurately interpret what the absence of a milestone means.
(It could mean any one of the following: (a) the State did not make a determination/decision whether or not to
require the activity; (b) the State made a determination/decision that the system is not required to perform
the activity; or (c) the State made a determination/decision that the system is required to perform the
activity but the State did not report this determination/decision to EPA.) Redefining the milestone and
requiring it to be reported to EPA for every system that exceeds an AL adds unnecessary burden.
2. Redundant reporting since States are required to report a violation if the system fails to meet the
milestone.
Under this new option, the reporting of the ``deemed'' and ``done''
milestones would be required for every system, including those that
have achieved the milestone prior to the effective date of the revised
State reporting requirements. EPA also recognizes that States may need
time to adapt their internal data management systems to facilitate
reporting under this new option. For these reasons, EPA plans to allow
States at least 18 months from the date of promulgation of the LCR
Minor Revisions Rule to submit data in accordance with the revised
State reporting requirements. At the end of this transition period,
however, EPA would expect all States to have submitted the ``deemed''
and ``done'' milestones for all systems which have completed the
milestone(s).
Figure 1 shows the estimated change in national annual burden hours
for the years 1999 through 2009 5 if this new option is
implemented. The estimated additional burden in 1999 and 2000 is due
primarily to the requirement to report the ``deemed'' and ``done''
milestones for all systems.6 EPA estimates that States will
need to report the ``deemed'' milestone for all systems and the
``done'' milestone for all systems except those triggered into lead
service line replacement by the end of the 18-month transition period.
The slight increases estimated for the years 2001, 2004, and 2007 are
due to the reporting of all 90th percentile lead values for large and
medium-size systems.
---------------------------------------------------------------------------
\5\ 1998 through 2009 represents the remaining time in the
original 18-year planning window for which burden/costs were
estimated when the LCR was promulgated in 1991.
\6\ Consistent with Agency policy, burden estimates are derived
using a static inventory. Therefore, the estimates do not include
any burden for new systems that might come into existence after the
promulgation of the rule. The Agency also has used simplifying
assumptions that all systems are in compliance with the rule's
deadlines and that action level exceedances occurred during the
first round of initial monitoring.
[[Page 20046]]
[GRAPHIC] [TIFF OMITTED] TP22AP98.001
EPA believes this new State reporting requirement option will
significantly improve the Agency's ability to assess program progress
toward the Rule's goals and, at the same time, minimize the necessity
of requesting additional clarifying information from the States on a
large number of systems on an ad hoc, quick turnaround, basis. EPA
plans to use these data to demonstrate progress toward reducing the
levels of lead and copper at the tap in several ways. In addition to
computing compliance statistics, the Agency plans to utilize 90th
percentile data for large and medium-size systems to characterize
overall national changes in the levels of lead at the tap since these
systems serve approximately 90% of the population that receives their
drinking water from public water systems. Under the existing
regulation, States are not required to report 90th percentile lead
levels unless the system exceeds 0.015 mg/L. The Agency therefore
cannot assess changes in 90th percentile levels below this level. The
remaining milestones to be reported under this new option also will
provide EPA a much better capability to reflect a system's actual
implementation status.
Some of the milestones that EPA would eliminate from the State
reporting requirements under the new option pertain to State decision-
making. Under current reporting requirements, States report to EPA only
when they determine that a system must complete certain actions, for
example, install new treatment. The absence of a milestone does not
necessarily imply that a State has failed to make a timely and
appropriate determination, however, since there is no way to reflect
the fact that the State determined that no treatment is needed. Rather
than impose the significant burden of reporting each State decision for
every system, the Agency plans to use other tools such as performance
agreements, periodic program audits, and data verifications to ensure
that States are meeting their primacy requirements satisfactorily. The
explicit reporting of State-determination milestones to EPA would not
eliminate the need for these tools, since they are needed if EPA and
the public are to have confidence in the integrity of the data in the
national data base. EPA believes that the benefits described above
justify the added reporting burden.
EPA solicits comments on this new option, including the adequacy of
the information that would be required to be reported on a routine
basis. EPA requests that commenters who believe the information to be
reported under this option is not adequate specify the additional
information EPA should seek to obtain, how often, and in what manner
(e.g., quarterly reports to the national data base, special one-time
reports, etc.) EPA also solicits comments on the possibility of
requiring a separate report or reports, by a date or dates certain, on
certain milestones, for example, those systems for which the State has
designated OWQPs or maximum permissible source water levels. EPA is
especially looking for comments on the usefulness of such information
as well as the burden of providing the information to EPA. Finally, for
the ``Done'' milestone, EPA requests comment on whether the Agency
should require reporting for all systems or only for those systems that
continue to exceed an action level after optimizing corrosion control.
While the preceding discussion describes EPA's current thinking
concerning State reporting requirements, the Agency will carefully
review all comments on this notice as well as prior comments on the
proposed rulemaking in formulating the requirements contained in the
final rulemaking.
C. Simultaneous Compliance Considerations: D/DBP Stage 1 Enhanced
Coagulation Requirements and the LCR
On November 3, 1997, EPA published a Notice of Data Availability
pertaining to the proposed rule for NPDWRs for Disinfectants and
Disinfection Byproducts (62 FR 59388). In response to that Notice, the
Agency received comments that express concern regarding utilities'
ability to comply with the Stage 1 D/DBP enhanced coagulation
requirements and LCR requirements simultaneously. Commenters stated
that enhanced coagulation will lower the pH and alkalinity of the water
during treatment. They indicated concern that the lower pH and
alkalinity levels may place utilities in noncompliance with the LCR by
causing violations of OWQPs and/or an exceedence of the lead or copper
action levels. EPA is not aware of data that suggests that low pH and
alkalinity levels cannot be adjusted upward
[[Page 20047]]
following enhanced coagulation to meet LCR compliance requirements.
However, as discussed below, the Agency solicits further comment and
data on this issue.
The LCR separates public water systems into three categories: large
( > 50,000), medium-size ( 50,000 but > 3,300) and small (<
3,300). Small and medium-size systems that do not exceed the lead and
copper action levels for two consecutive six-month monitoring periods
are deemed to have optimized corrosion control. These systems do not
have to operate under OWQPs. Optimal water quality control parameters
consist of pH, alkalinity, calcium concentration, and phosphate and
silicate corrosion inhibitors. They are designated by the State. Small
and medium-size systems that continue to exceed an action level after
installation of corrosion control treatment must operate under State-
specified OWQPs. Large systems must operate under OWQPs specified by
the State unless they are deemed to have optimized corrosion control
pursuant to Sec. 141.81(b)(3).
Maintenance of each OWQP mentioned above (except for calcium
concentration) is directly related to meeting specified pH and
alkalinity levels at the entry point to the distribution system and in
tap samples to establish LCR compliance. In treatment trains that EPA
is aware of, utilities have the technological capability to raise the
pH (by adding caustic--NaOH, Ca(OH)2) and alkalinity (by
adding Na2CO3 or NaHCO3) of the water following
enhanced coagulation and before it enters the distribution system.
Although certain utilities may need to add chemical feed points to
provide chemical adjustment, pH and alkalinity can be maintained at the
values used prior to the implementation of enhanced coagulation.
Systems that operate with pH and alkalinity OWQPs should be able to
meet the State-prescribed values by providing pH and alkalinity
adjustment prior to entry to the distribution system. Systems that
operate without pH and alkalinity OWQPs can raise the pH and alkalinity
to the levels they were at before enhanced coagulation by providing
chemical adjustment prior to distribution system entry.
The goal of calcium carbonate stabilization is to precipitate a
layer of CaCO3 scale on the pipe wall to protect it from
corrosion. As the pH of a water decreases, the concentration of
bicarbonate increases and the concentration of carbonate, which
combines with calcium to form the desired CaCO3, decreases.
At the lower pH used during enhanced coagulation, it will generally be
more difficult to form calcium carbonate. However, post-coagulation pH
adjustment will increase the pH and hence the concentration of
carbonate available to form calcium carbonate scale. Systems that must
meet a specific calcium concentration to remain in compliance with
OWQPs should not experience an increase in LCR violations due to the
practice of enhanced coagulation provided the pH is adjusted prior to
distribution system entry and the calcium level in the water prior to
and after implementation of enhanced coagulation remains the same.
EPA recognizes that the inorganic composition of the water may
change slightly due to enhanced coagulation. For example, small amounts
of anions and compounds that can affect corrosion rates (Cl,
SO4-2) may be removed or added to the water. The effect of
these constituents is difficult to predict, but EPA believes they
should be minimal for the great majority of systems due to the
generally modest changes in the water's inorganic composition and
because alkalinity and pH levels have a greater influence on corrosion
rates. Increases in sulfate concentration due to increased alum
addition during enhanced coagulation can actually lower the corrosion
rates of lead pipe. EPA requests comment on whether changes in the
inorganic matrix can be quantified to allow States to easily assess
potential impacts to corrosion control.
EPA requests comment on how lowering the pH and alkalinity during
enhanced coagulation may cause LCR compliance problems, given that both
pH and alkalinity levels can be adjusted to meet OWQPs prior to entry
to the distribution system. EPA also requests comment on whether
decreasing the pH and alkalinity during enhanced coagulation, and then
increasing it prior to distribution system entry, may increase
exceedences of lead and copper action levels.
EPA is currently developing a simultaneous compliance guidance
document working with stakeholders. The document will provide guidance
to States and systems on maintaining compliance with other regulatory
requirements (including the LCR) during and after the implementation of
the Stage 1 D/DBP rule and the Interim Enhanced Surface Water Treatment
Rule. EPA requests comment on what issues should be addressed in the
guidance to mitigate concerns about simultaneous compliance with
enhanced coagulation and LCR requirements. Further, the Agency requests
comment on whether the proposed enhanced coagulation requirements and
the existing LCR provisions that allow adjustment of corrosion control
plans are flexible enough to address simultaneous compliance issues. Is
additional regulatory language necessary to address this issue, or is
guidance sufficient to mitigate potential compliance problems?
List of Subjects
40 CFR Part 141
Environmental protection, Chemicals, Indians-lands
Intergovernmental relations, Reporting and recordkeeping requirements,
Water supply.
40 CFR Part 142
Administrative practice and procedure, Chemicals, Indians-lands,
Reporting and recordkeeping requirements, Water supply.
Dated: April 16, 1998.
Dana D. Minerva,
Acting Assistant Administrator.
[FR Doc. 98-10713 Filed 4-21-98; 8:45 am]
BILLING CODE 6560-50-P