Massachusetts Water Resources Authority

Charlestown Navy Yard

100 First Avenue

Boston, Massachusetts 02129

> Telephone: (617) 242-6000
>
> Facsimile: (617) 788-4899
>
> January 9, 2004

Water Docket

Environmental Protection Agency, Mail Code 4101T

1200 Pennsylvania Avenue, N.W.

Washington, D.C. 20460

RE: Long-Term 2 Enhanced Surface Water Treatment Rule, Proposed Rule, 68
[Federal Register]{.underline} 47639, Docket No. OW--2002--0039

Filed Electronically to EPA Docket

Dear Sir or Madam:

The Massachusetts Water Resources Authority (MWRA) appreciates the
opportunity to comment on the Proposed Long-Term 2 Enhanced Surface
Water Treatment Rule (LT2ESWTR) released on August 11, 2003 (68 [Federal
Register]{.underline} 47639). Given the volume of related materials, we
also appreciate that EPA extended the comment period.

MWRA is an independent authority providing wholesale water and
wastewater service to approximately 2.5 million people in 61 cities and
towns primarily in the Boston metropolitan area. MWRA provides water
service from the well-protected Quabbin and Wachusett Reservoirs in
Central Massachusetts and is in the midst of a 10-year 1.7 billion
dollar integrated water supply improvement program which includes
continued aggressive watershed protection, a new water treatment plant
using ozone and chloramines, a 17-mile long, 14-foot diameter new
transmission tunnel for supply redundancy, replacement of open
distribution reservoirs with covered storage and pipeline rehabilitation
in both the MWRA system and our member community systems. Investments in
our water and wastewater infrastructure over the past 20 years total
over 6 billion dollars.

MWRA was actively involved in the Stage 2 Microbial / Disinfection
By-Products Federal Advisory Committee (FACA) as a member of the
Unfiltered Systems Working Group and agreed to the working group being a
signatory to the Agreement in Principle (AIP). The Agreement in
Principle included the following provisions specifically related to
unfiltered systems:

-   *Continue to meet filtration avoidance criteria, and*

# Provide 4 log virus inactivation, and

-   *Provide 3 log Giardia lamblia inactivation, and*

-   *Provide 2 log Cryptosporidium inactivation.*

-   *Overall inactivation requirements must be met using a minimum of 2
    disinfectants.*

-   *Ongoing monitoring and any eventual reassignment to risk bins for
    unfiltered systems will be consistent with requirements for other
    systems of their size, with the provision that unfiltered systems
    must demonstrate that their Cryptosporidium occurrence level
    continues to be less than or equal to 1 in 100 liters (or
    equivalent, using advanced methods) or provide 3 logs of
    Cryptosporidium inactivation.*

**[General Comments:]{.underline}**

MWRA offers the following comments based on our review of the rule
language, preamble, guidance, and decision support documents. As we
reviewed the documents three overall themes struck us.

First, that the overall broad structure of the proposed regulation
represents the generally reasonable compromises of the Agreement in
Principle. These include moving beyond the "one size fits all" approach
of the original Surface Water Treatment Rule to treatment requirements
locally tailored to source water quality, a measured step forward on the
control of *Cryptosporidium*, and recognition of ultraviolet light (UV)
as a significant cost-effective new treatment technology.

Second, that the devil is in the details, and that we were less
comfortable with many of the implementing details in the regulation and
guidance documents. This is particularly obvious with UV: what the broad
outline gives, the details take away, with excess complexity and extreme
layers of conservatism. We urge EPA to carefully sort through the
comments received, focusing on simplifying the final regulations, and
reducing unnecessary and costly requirements for overlapping safety and
redundancy factors.

Third, that even where we agreed with the substance of the regulation,
the supporting cost-benefit analysis in the preamble seemed to be
substantially over-reaching what the science and evidence would justify.
It was clear during the FACA process that the data to develop a cogent
risk and benefits estimation was lacking. It still seems to be lacking.
EPA will need to carefully rework this material if the analysis is to be
believable and provide a basis for what will be substantial investments
by water systems across the nation.

**[Requests for comments on the treatment requirements for unfiltered
systems]{.underline}**:

As it relates to those provisions directly affecting unfiltered surface
water supplies, MWRA believes that the draft as published is in
substantial agreement with the Agreement in Principle.

*EPA solicited comments on the proposed requirement for unfiltered
systems to use two disinfectants and for each disinfectant to meet by
itself the inactivation requirement for at least one regulated
pathogen*.

While no specific compelling technical argument is made for its
inclusion in the regulation, the requirement as detailed in the draft
regulations and preamble meets the intent of the FACA Agreement in
Principle (AIP). As the risk analysis for unfiltered systems already
assumed meeting a *minimum* inactivation (rather than the *average*
removal credited to filtration plants), and given that by their very
nature unfiltered sources have low *Cryptosporidium* levels, there may
no demonstrable health benefit from adding a second disinfectant at all
times. In fact, depending on the choice of the disinfectants, there may
be an increase in exposure to disinfection byproducts (or a lost
opportunity to realize a reduction). Ongoing monitoring by MWRA and
several of the largest unfiltered utilities indicates that the exposure
assumptions for *Cryptosporidium* levels used by EPA in the preamble may
be extremely conservative.

MWRA urges EPA to carefully conduct a risk analysis based on current
occurrence and health data, and provide that documentation in the
preamble to the final rule before finalizing the two primary
disinfectants requirement.

MWRA is also concerned that while the preamble makes it clear that the
second primary disinfectant only meet the full disinfection requirement
for one pathogen, such as the example of 4-log virus inactivation, the
regulatory language may be subject to misinterpretation by primacy
agencies as they draft their own regulations. In addition, it is also
possible that there could be misinterpretation if a system used three
disinfectants, rather than two. The language in the regulation itself
should be as clear as possible.

*EPA solicited comments on an alternate approach that would allow
systems to meet the inactivation requirements using any combination of
one or more disinfectants that achieved the required inactivation level
for all pathogens.*

This approach would allow utilities additional flexibility to design and
operate treatment plants that are responsive to the unique local water
quality conditions. It does not appear to have any substantive
disadvantages over the more rigid proposal in the current draft, and may
allow more systems to effectively leverage their existing treatment
investments with less expensive treatment process additions. More
importantly, it may allow some systems to minimize their reliance on
chlorine. MWRA is supportive of this additional flexibility.

*EPA solicited comments on whether the proposed requirements for use of
two disinfectants establish an adequate level of multiple barriers in
the treatment provided by unfiltered systems.*

The form of the solicitation ignores the unique distinction of the
unfiltered systems. By virtue of complying with stringent source water
quality and watershed control criteria contained in the Surface Water
Treatment Rule, unfiltered systems already have a substantive barrier in
place prior to treatment. The addition of the second primary
disinfectant requirement represents not just the traditional "belt and
suspenders" of high quality well protected source water and effective
disinfection, but an approach of "belt, suspenders and two guys holding
up your pants". The proposed regulation proposes no similar degree of
extreme redundancy for the substantially more at risk systems with
wholly unprotected source waters that rely for substantially all of
their *Cryptosporidium* risk reduction on the single barrier of
filtration. Bin 1 systems have no source water protection, and rely on
the average performance of their filters to achieve the required 3-log
reduction of *Cryptosporidium.* The risk analysis suggests that Bin 2
utilities need 4-reduction, but redundancy is only required for 1-log.
And so on. There simply does not appear to be a data supported,
internally consistent argument for this modification to the proposed
rule. MWRA urges EPA not to adopt this modification.

In response to all three of these requests for comment on the second
primary disinfectant requirement, MWRA urges that the current proposal
represent the most stringent disinfection requirement that EPA considers
in drafting the final regulations. Given the lack of a demonstrable
health benefit, we urge EPA to include as much flexibility for utilities
to make site-specific decisions as possible.

EPA also solicited comments on whether or how this possibility of
unfiltered systems having a mean source water Cryptosporidium level of
0.075 oocysts/L or higher should be addressed.

Based on the current data available to MWRA and the other unfiltered
systems, and to EPA, this does not appear to be a realistic scenario.
However, there are three significant physical and regulatory differences
between filtered systems with unprotected sources, and those systems
that meet the SWTR filtration waiver criteria which we believe render
the question moot.

First, all unfiltered systems have source water watersheds which must be
annually reviewed by the state primacy agency for adequate control of
potential health threats: the Interim Enhanced Surface Water Treatment
Rule has already made the inclusion of *Cryptosporidium* control a
required goal of watershed protection plans. Any evidence of an actual
source of *Cryptosporidium* at levels high enough to affect source water
quality at the intake should already be grounds for the state primacy
agency to take action to order the elimination of the threat or the
additional of filtration. No new regulatory restrictions or authority is
required.

Second, by their nature, the source waters of unfiltered supplies are
significantly more likely to have a higher fraction of older, more
degraded, and non-infectious oocysts, and to have a lower fraction of
potentially human infectious oocysts. While for the purpose of the
binning procedure in the Agreement in Principle, the unfiltered systems
agreed with the simplifying approach to treat all enumerated oocysts the
same way, they are not. Many filtered systems have direct discharges of
sewerage treatment effluent to their sources, in some cases in large
volumes and in close proximity. This is certainly an opportunity for
fresh, human infectious oocysts to arrive at their treatment plants.
This is not the case for unfiltered systems. The detention time in most
unfiltered systems is substantial: not hours or days from pollutant
source to source water sampling point, but months or years. For example,
MWRA's reservoir system has a detention time of almost 5 years. The
physical nature of such systems serves to allow for natural degradation,
reducing the potential of any given enumerated oocyst to be infectious.
And finally, because of their well-protected watersheds, it is likely
that any occysts present came from non-human sources.

Third, all unfiltered systems are required to have some type of outbreak
monitoring program in place and annually must demonstrate that there
have been no water-borne disease outbreaks to their state primacy
agency. Filtered utilities are not required to do this. In MWRA's case,
we fund approximately four staff at the Boston Public Health Commission
and the state Department of Public Health to conduct active disease
surveillance of both endemic levels and outbreaks. This additional layer
of vigilance and oversight provides an additional opportunity to
discover any actual threat to public health, and any evidence of a
source water related disease outbreak would be grounds for the primacy
agency to withdraw the waiver of filtration status.

**[Responses to other aspects the treatment requirements for unfiltered
systems]{.underline}**:

[Minimum level of *Cryptosporidium* inactivation required]{.underline}:
The preamble described the process used to establish the required two
log (99%) inactivation requirement. The analysis uses the simplifying
assumption that the ICR data for unfiltereds is only about 10 times
lower than that of utilities required to filter, and than further
assumes that a well operated filtration plant can achieve an *average*
of 3 log reduction[^1]. Unfiltered systems are required to utilize
disinfection with a regulatory required target of a *minimum* of 2 logs
inactivation: in practice to reliably achieve the minimum requirement,
systems must employ a margin of safety to account for normal variations
in flow, temperature and pH as well as disinfectant dosing. For example,
MWRA routinely sets a target of 130 to 150 percent of the required CT as
its operational target. Both by the use of *minimum* rather than
*average*, and by the very conservative exposure assumptions, the draft
regulations require more treatment than the actual risk would warrant.
This in effect diverts resources away from other investments that would
have a higher water quality or public health benefit.

Ongoing monitoring by MWRA of its finished water indicates that the
exposure assumptions for *Cryptosporidium* levels used by EPA in the
preamble may be extremely conservative. Based on over two years of
weekly composite samples of 1,000 liters each taken with the IDEXX foam
filter (a total of 124,000 liters sampled and analyzed using Method
1623) MWRA's actual levels are averaging 0.05 oocysts per 100 liters:
more than an order of magnitude lower than the average levels cited for
unfiltered utilities from the ICR, and almost 2 orders lower than the
median. This is particularly note worthy given that these results are
based on using sample volumes and analytic techniques which are at least
50 to 100 times more sensitive than the very low volumes and low
recoveries of many ICR samples used as the data source for much of the
analysis cited in the preamble.

MWRA urges EPA to consider adding at least one additional bin for
unfiltered systems with lower levels of *Cryptosporidium* in their
source waters. This would move the regulatory approach for unfiltereds
more nearly in line with that filtered systems, and open up additional
treatment flexibility for systems which already have treatment
facilities which might be modified to achieve 1-log *Cryptosporidium*
inactivation and for groundwater under the direct influence of surface
waters (GWUDI) systems which may have very low *Cryptosporidium* levels.
Filtered systems have four separate bins -- it is not unreasonable that
the unfiltered systems have at least three.

[Compliance Determination for UV disinfection:]{.underline} For
unfiltered systems using UV disinfection to meet the required
inactivation requirements, the draft regulations propose that compliance
with the standard be based on a 95^th^ percentile. This is a commonsense
approach to extending the existing SWTR requirements for chemical
disinfection in unfiltered systems to UV, and MWRA supports this
approach. In that it provides additional information on disinfection
system performance, particularly short periods of disruption, it
improves on the current reporting system. It is protective of public
health, while avoiding the excesses of extraordinary redundancy.

EPA may want to consider separating "off-spec" from down time (i.e. lamp
off). There is clearly a difference in the health risk of having no UV
irradiation from that of providing 98 percent as much as is required. As
most systems will have multiple reactors, having a single reactor at
slightly less that full capacity, and others above their required
capacity, may still yield an average above the minimum. MWRA urges EPA
to draft the final rule and guidance to provide clarity on this topic.
MWRA is not supportive of the suggested alternative approach that
suggests that each and very reactor must meet the 95% standard
independently. The intent is to ensure that the water leaving the plant
is within specification.

EPA may also want to consider the merit of offering this approach as an
alternate for compliance for those unfiltered systems that use chemical
disinfectants, but monitor continuously. It would provide additional
data to operators and primacy agencies on how plants actually operate
over the course of the days and month, and capture and regulate short
periods of 'off-spec' or under disinfected water in periods other than
the hour of maximum flow rate.

[Minor Exceedances of Filtration Avoidance Criteria:]{.underline}
Another area where the regulations might be improved by consistent
adoption of the approaches afforded the filtered systems is the
consequence of minor exceedances of the filtration avoidance criteria.
As the SWTR regulations have been promulgated, and as their approach is
extended by these new regulations, almost any minor water quality
variation or upset in treatment plant operation automatically triggers a
violation, but more critically, the requirement for that system to add
filtration. Filtered systems, on the other hand, receive the violation,
and must work with their state primacy agency to come back into
compliance. Normally, a water quality or process upset results in
changes to standard operating procedures, additional staff training, or
adjustments to process control set points. Normally it would not result
in an immediate and unconsidered requirement for substantial capital
investment in new treatment processes. This, however, is the situation
in the current and proposed rules for unfiltered systems.

MWRA urges EPA to consider language in the final rule that allows the
state primacy agency to examine the specifics of any exceedance of an
avoidance criterion, and determine with the water system, the most
appropriate means to come back into compliance. In some cases this may
very well be to add filtration, but in others it may be to adjust
disinfectant doses or chemicals, or to move an intake location, or
simply change operating procedures. Water systems must be sure that any
capital investment cost-effectively results in real risk reductions and
water quality improvements for consumers. There are always competing
investment opportunities at the source, within the treatment processes
and within the distribution system. Let the primacy agency and the
specific facts dictate the solution.

**[Treatment Issues Affecting Both Filtered and Unfiltered
Systems:]{.underline}**

[Implications of Missing or Un-Approved *Cryptosporidium*
Samples:]{.underline} As currently drafted the rule requires that a 24
month sampling period must be an unbroken record of samples; any missing
samples, or samples which for whatever reason fail to meet laboratory
quality assurance standards result in the system being required to
provide the maximum level of treatment. The Agreement in Principle does
not require this, nor is it required by good sampling design. Any number
of unintentional utility or laboratory errors or accidents could result
in a missing sample. A missing sample does not alter the source water
quality nor the underlying public health risk health. A missed sample
costing a few hundred dollars could result in the expenditure of tens to
hundreds of millions of dollars when there was no basis in public health
risk. To so severely penalize these commonplace occurrences is
unacceptable public policy.

We urge EPA to consider allowing resampling and the addition of
additional samples at the tail end of the sampling period. Both are
needed for particular circumstances, and neither influences the
resultant source water concentration estimation. We are supportive of
AWWA's more detailed recommendations on this topic:

-   Additional provisions to take replacement samples at the end of the
    defined monitoring period,

-   Greater flexibility in handling of missed samples when utility
    collected 48 or more samples, and

-   Greater flexibility in handling of missed samples in pre-existing
    data.

The latter two provisions are of particular interest to unfiltered
utilities as many already collect source water samples regularly or
expect to conduct more frequent sampling for the purposes of the LT2
rule.

[Excessive Conservatism in UV Guidance Manual:]{.underline} An important
factor in the completion of the FACA process resulting in consensus on
the AIP was the recognition that inactivation of Cryptosporidium using
UV was possible at a low cost. Unfortunately, as developed in the UV
Disinfection Guidance manual, the multiple layers of redundant safety
factors conspire to unnecessarily raise the costs of compliance. MWRA's
Wachusett Reservoir system serving metro Boston is the second largest
unfiltered system in the US. We are concerned that the validation
protocols developed in the guidance manual be such that we can
cost-effectively procure UV systems. For larger reactors, computational
fluid dynamics (CFD) modeling may be a cost-effective validation method.
We urge EPA to explicitly permit CFD analysis without site-specific flow
testing in the regulation, with more specific technical requirements to
be developed and presented in guidance manuals as the science advances.
Not doing so may eliminate this option for the future.

The UV Disinfection Guidance Manual must explicitly allow use of CFD to
predict UV inactivation for reactors that are too large to subject to
the physical validation test protocol currently described in the
Guidance Manual. The required quantities of test organisms, the large
volumes of water needed, and the disposal of contaminated water during
testing, all present significantly different challenges for bioassay
tests of large reactors. In addition, the safety factor, if any, added
due to the use of CFD must be reasonable: the 20% increase in required
dose described in the current version of the manual is absurdly
conservative.

More information is needed as to whether and what future changes would
require revalidation. It is important to allow for incorporation of new
UV and water treatment technology in the future. Would future
incorporation of new UV lamps/sensors require complete revalidation?
Would changes to other processes upstream of UV in a treatment facility
require revalidation? If initially validated as an unfiltered system,
would future addition of filtration require revalidation? The regulation
and guidance manual must provide clear direction to implementing state
primacy agencies on this topic.

The MWRA urges EPA to use the UV dose table for Cryptosporidium and
Giardia from the proposed rule in the final rule. The UV Manual should
be refocused on a more straightforward process to ensure that the
applied UV dose reliably equals or exceeds the required dose in the
rule. Clarity and simplicity will be needed if UV is expected to be the
inactivation technology of choice for compliance with the LT2.

[Excessive Conservatism in Application of Ozone:]{.underline} MWRA is
aware of and appreciates the progress made by EPA between the
pre-proposal draft and this draft in realistically determining required
CT levels. We participated in the technical evaluations and review of
alternative approaches conducted by AWWA. While substantial progress has
been made, MWRA still believes that the statistical approach adds
excessive conservatism to the calculation of the required CT for a given
level of inactivation, raising capital and operating costs, and
increasing the levels of ozone byproducts unnecessarily.

Because of the higher ozone doses required to inactivate Cryptosporidium
compared to Giardia, particularly in the colder water temperatures that
several of our systems experience, it is important to further develop
the SWTR concept of segregated flow analysis (SFA) to allow utilities to
better estimate and manage the application of ozone for CT. SFA is not
currently in the Guidance Manual: we urge that the Guidance Manual
explicitly indicate that a system may demonstrate the SFA method to the
Primacy Agency for use at its plant, include an appendix to the Guidance
Manual that details the use of the SFA method.

**[Inaccuracies in Risk and Cost Information Presented in the
Preamble:]{.underline}**

EPA estimates on page 47743 that the new rule is expected to reduce
cases of illness for the 12 million people served by unfiltered systems
by an estimated 168,000-547,000 cases, and 28 to 91 premature deaths
annually. The EPA estimates that up to 1 in 22 people in unfiltered
systems are getting ill.

EPA's estimates come with well-developed lists of studies referenced,
and assumptions made. However, notably absent is any attempt to "ground
truth" the results. A primary responsibility of any analyst creating an
estimate is to look for alternative ways to validate the answers: if the
answer is not the correct order of magnitude, additional research or an
alternative approach may be called for. This step appears to have been
missed out. MWRA and several other systems with aggressive public health
surveillance systems have conducted a ground- truthing of the preamble
estimates based on actual local data on illnesses and deaths.

With approximately 1.6 million customers in fully supplied communities,
MWRA represents 13.3% of EPA's estimate of the 12 million person served
by unfiltered systems. Thus, the EPA estimate would yield a presumed
annual *reduction* of between 22,400 and 72,900 cases, and between 4 and
12 deaths. Yet, under active surveillance, there were only 11 cases of
Massachusetts-acquired cryptosporidiosis in 2001 and 7 in 2002.
Recognizing that even active surveillance does not capture every case
(although it generally will catch the most serious cases), and adjusting
for an under-reporting factor of 50 or 100, as reported by the CDC (Mead
et al, Emerging Infectious Diseases, Vol. 5, No.5), the preamble
estimates appear to be off by a substantial amount. Essentially, the
analysis suggests that adding additional disinfection will reduce 22,000
to 72,000 more cases than the actual public health surveillance
indicates occur in total.

The deaths attributed to cryptosporidiosis also seem high. Through our
active surveillance and an informal review of Massachusetts Vital
Records, there is no record of any deaths in Massachusetts associated
with cryptosporidiosis in the past several years. While it is possible
that some deaths might be misattributed to other causes, it is
reasonable to assume that any death caused by cryptosporidiosis would at
least result in a reported case. The estimates in the preamble assume
that improved disinfection will reduce more water-borne illness related
deaths than were reported as total cases, yet there are no reported
deaths in Massachusetts, let alone the MWRA service area. This estimate
for mortality associated with cryptosporidiosis seems incorrect.

Another way to ground truth the estimates is to review the information
now being collected by state and local health authorities as part of
bio-terrorism detection systems. MWRA participates with the
Massachusetts Department of Public Health and Boston Public Health
Commission in a series of surveillance programs to detect any changes in
a variety of syndromic based illnesses including monitoring sentinel
sites (nursing homes, schools, and prisons) for diarrheal disease, daily
analysis of electronic records at a cooperating HMO and hospital
emergency room admissions, and weekly review of anti-diarrheal medicine
sales.

The level of diarrheal disease estimated to be caused by
cryptosporidiosis in unfiltered systems is not credible, and ignores
years of active surveillance work completed by MWRA and other large
utilities across the country. MWRA understands that the preamble numbers
are estimates, but the degree to which the estimated number of cases
assumed to be reduced is different than the actual number of total cases
from all sources found is dramatic. Of course, if the number of cases of
illnesses is grossly overestimated, then the estimates of benefits are
also grossly overestimated. MWRA urges EPA to reach out to state and
local health authorities to develop more realistic estimates for the
final rule.

The Appendices to the Economic Analysis present the cost estimating
tables and graphs used by EPA is estimating the cost of complying with
the proposed rule. MWRA is currently in the process of conceptual design
for two UV facilities -- one with a capacity of 405 mgd, the other with
a capacity of 25 mgd. In each case the capital costs to add UV to the
water treatment plants are almost twice what the cost tables would
estimate. The larger plant is estimated by EPA to cost about \$24
million; our current estimate is \$43.5. The smaller plant is estimated
by EPA to cost \$1.8 million versus our cost estimate of \$4.7 million.
We are aware of many other water systems with similar experiences, with
actual cost estimates about twice what EPA is using in the cost/benefit
analyses. We urge EPA to conduct additional work in developing realistic
cost estimates for the final rule.

MWRA is also concerned that the dollar values placed on the cases of
illness are overstated. Many of the illnesses indicated may be minor or
even asymptomatic. Cases that do not show up on any of the public health
radar screens may simply be too mild to be economically significant.
Based on the discussion above, it is clear that the only way to arrive
at the number of cases included in the analysis is to include a vast
number of "illnesses" in which the individual did not realize they were
sick.

Thank you for the opportunity to comment on these important regulations.
If we can provide EPA any additional data on any of these topics, please
feel free to contact us. You may direct questions to Stephen
Estes-Smargiassi, Director of Planning at 617-788-4303
(smargias@mwra.state.ma.us).

Very Truly Yours,

\-- Signed \--

Michael J. Hornbrook

Chief Operating Officer

[^1]: A review of the preamble reveals that virtually every reference to
    filtration performance cites average performance, rather than the
    minimum performance of the particular technology. Given the higher
    likelihood of extreme variability in an uncontrolled and unprotected
    source water, attention to minimum performance for filtration
    technologies would have seemed commonsensical. Given that literature
    available does not seem to support the ability to achieve this, some
    explicit acknowledgement of the disparate approaches might be
    appropriate in the final rule documents.