December 20, 2001
Chesapeake Bay Program Water Quality Standards Coordinators Team
Final Responses to Comments on the July 3,2001
Working Draft Chesapeake Bay Criteria and Designated Use
Documents General Comments
From Virginia DEQ
1.	Efforts toward revising Virginia's water quality standards, as an outcome of this process,
will have the benefit of correcting deficiencies in the existing dissolved oxygen standard.
One such deficiency was the definition and use of natural conditions. The
Commonwealth has no interest in creating similar problems with the other criteria under
development for water clarity and chlorophyll, such as applying unobtainable clarity
requirements in areas of turbidity maximum and naturally high sediment resuspension, or
stringent chlorophyll levels in areas with historically elevated concentrations, again due
to natural conditions (e.g., in small embayments and creeks).
Response: The scientific approach to derivation of the Bay specific criteria along
with the detailed implementation guidelines fully addresses the concerns expressed
above.
2.	The exact boundaries of the impaired waters that EPA identified for inclusion on
Virginia's 1998 303(d) list are still unclear, and this issue has already come up several
times during public briefings on the draft criteria and designated uses. Therefore, EPA
needs to accurately delineate the 303(d) impaired waters (re. 5/10/99 EPA letter to DEQ)
because this is vital information to be used in the geographic application of the new
criteria and designated uses, and determining where the de-listing process will apply.
Response: Determination of the exact boundaries of impaired waters within
Virginia are the responsibility of EPA, the Chesapeake Bay Program's Water
Quality Standards Coordinators team.
From CBF
3.	Overall, our main concern is that the refined designated uses and criteria as drafted
cannot advance the efforts to improve water quality of the Chesapeake Bay if they merely
aim to meet existing or easily attainable conditions. While the result of such efforts
might "de-list" the Bay, the question remains whether the Bay could honestly be
considered "clean". A truly restored Bay requires the goals to be set at levels that do not,
at present, widely exist in the Bay. This does not imply that we must work toward
unrealistic goals, such as those that existed centuries ago, but certainly we should strive
for conditions present prior to the Bay's decline.
Response: As currently drafted, neither the refined designated uses and nor the
draft Bay criteria describe existing or "easily attainable" water quality conditions.
The draft criteria are based on the latest and best scientific information for defining
water quality conditions fully supportive of a wide array of Bay species. No
consideration of attainability is factored into the derivation of the criteria values.

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The designated uses are being defined largely by natural physical habitat
considerations throughout tidal waters. See the responses to comments on the
working draft designated uses for more details.
Implementation
4.	CBF is concerned that, while much time and effort has been allotted to the development
of the criteria themselves, there is little to nothing on the actual implementation of these
new criteria and designated uses. Since the success of these new water quality standards
greatly depends upon adoption by all four states (Virginia, Maryland, Delaware, and the
District of Columbia) and support from the other Bay states (Pennsylvania, New York,
and West Virginia), information should be provided to answer substantive questions. We
look forward to reviewing and commenting on the draft Implementation Guidance
document.
Response: The revised draft criteria/uses document contains an extensive set of
implementation guidelines for each of the three proposed Bay criteria as an integral
component of the overall criteria document.
In particular, CBF has identified several issues related to implementation of the draft
criteria and designated uses.
Response: See responses to comments 5-11 below.
5.	Integrating the different depths (e.g. open water, deep water, deep channel) and the
affiliated criteria into permits: How will these different criteria become requirements or
restrictions on discharges of oxygen-depleting substances at different depths? How will
these criteria apply to permitted dredge-and-fill activities in the Bay?
Response: Through a combination of analysis of monitoring data, application of an
array of diagnostic tools and use of Bay specific models, quantitative connections
have been and can be established between loads of nutrients and the reductions
needed to attain the different designated use defined dissolved oxygen criteria. The
Bay criteria will apply to permitted dredge and file activities in the Bay tidal waters
just as any other relevant state water quality standards as part of the structured
process for determining if and when a dredging operation violates state water
quality standards.
6.	Integrating the different designated use seasons (e.g. February 15th through June 10th for
migratory spawning and nursery) and the affiliated criteria into permits, in light of
significant lag times before pollution inputs are reduced: For instance, should seasonal
permit limits to protect the designated use for migratory spawning and nursery begin
earlier (e.g. January) in order to account for lag times in meeting the additional protection
required as of February 15th?
Response: Through application of a combination of Bay monitoring data analysis as
well as application of the Bay airshed, watershed and water quality models, the
required nutrient and sediment loadings and the relative timings of those loading
reductions needed to meet any of the five designated use driven Bay dissolved
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oxygen criteria can be directly determined. In the case of the linked models, they
provide tools for examining and evaluating the impact of nutrient/sediment loads to
the tidal waters months before the subject time period for application of the criteria.
7.	Defining and determining compliance/attainment and impairment: How will impairment
be reported (e.g. by waterbodies or individual designated uses)?
Response: As described in depth in each Bay criteria's implementation guidelines, it
is recommended that attainment of the Bay water quality criteria be determined at
the Chesapeake Bay Program segment scale by designated use category.
8.	Translating these criteria into permit limits for Nitrogen and Phosphorus concentrations:
While CBP has stated that there is "some level of trust" in these translations, there has
been no explanation given thus far as to how this will be done.
Response: EPA Headquarter has requested that Maryland, Virginia, Delaware and
District of Columbia water quality standards include specific "translator" language
spelling out how the three Bay criteria-dissolved oxygen, water clarity and
chlorophyll a-are to be translated into specific loads of nitrogen, phosphorus and
sediment through application of the Chesapeake Bay Program models. It is these
nutrient and sediment loads that would form the basis for any narrative or
numerical limits in permits. The tributary strategies, to be developed as the
implementation plans for achieving the adopted cap loads for nutrients and
sediment, will include all the specific details on the allocation of loading
reduction/loading cap responsibilities to individual facilities. Text outlining this
process in more detail has been added to the revised implementation guidelines
chapter.
9.	Changes in state water quality monitoring programs: How will states have to change
their monitoring programs to handle these new criteria and designated uses?
Response: The Chesapeake Bay Program's Monitoring and Assessment
Subcommittee is overseeing efforts currently underway to design a tidal monitoring
network, integrating both water quality and biological resource monitoring, to
collect the data necessary to directly measure attainment of the Bay criteria within
the tidal water designated uses. This network will involve significant enhancements
and changes to the current baywide monitoring program. The states are active
participants in the network design team charged with responsibility for bringing
forward a new tidal monitoring design by spring 2002.
10.	Given the complexity of the criteria, particularly the Chlorophyll a criteria, and
designated use proposals, how will a timely feedback loop be established to correct or
refine management strategies to meet the criteria? Given that these criteria are seasonal,
depth and salinity-related and there is often a lag time between loadings and effects, what
will the mechanism be to take corrective actions before damage is done? Total reliance
on model output is totally unacceptable.
Response: Given the existing set of Bay linked airshed-watershed-tidal water quality
models do not factor any lag time effects (e.g., groundwater flows) at this time,
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management decisions on overall cap loading goals, allocation of those cap loads,
and the resultant implementation strategies all must address the issue of lag time
effects. We have information right now as to the status of Bay and tidal river water
quality relative to the draft Bay criteria using monitoring data. The details of
whether criteria attainment will be determined strictly using monitoring data or a
blend of monitoring data and model simulated output is a topic still under
discussion amongst the Bay watershed partners.
11.	Will the criteria established for migratory spawning and nursery areas be applicable
above the Fall Line?
Response: The Bay criteria applicable to the migratory spawning and nursery
designated use are applicable only within tidal water as the use only extends to the
upper most reaches of tidally influenced waters. Text has been added to make this
clear within the revised draft criteria document.
General Comments on the UAA Workgroup Outline and Charge
12.	First, both documents speak of applicability to "water quality standards", seemingly in
contravention of caselaw, federal statute and regulation, and EPA policy which provide
that a UAA is only applicable to certain "designated uses". The document, along with
the associated "Economic Analysis Workgroup" document prepared by Rich Eskin and
Allison Wiedemann (7/26/01), indicates that the CBP is misconstruing what is required,
and is substantially underestimating, the difficult demonstration required under federal
law and regulation for a UAA.
Response: This comment is not relevant to the working draft criteria document.
Specific Comments on UAA Workgroup Charge
13.	EPA's longstanding policy, approved by the 5th Circuit Court of Appeals in Mississippi
Commission on Natural Resources v. Costle. 625 F. 2d 1269, 1277 (5th Cir. 1980), is that
economic considerations and technological feasibility cannot be considered in developing
water quality criteria, see, e.g., Nutrient Criteria Development; Notice of Ecoregional
Nutrient Criteria (January 9, 2001) 66 FR 1671, 1672 ("Water quality criteria developed
under section 304(a) are based solely on data and scientific judgments. They do not
consider economic impacts or the technological feasibility of meeting the criteria in
ambient water.").
Response: The Bay criteria are being derived solely on the basis of available data
and scientific findings of most relevance to Chesapeake Bay and the protection of
the proposed set of refined tidal water designated uses.
14.	The workgroup charge should be modified to eliminate any reference to a UAA for
"water quality standards". This is a Use Attainability Analysis, not a Criteria
Attainability Analysis. The term "designated uses" should replace "water quality
standards" in Items 1,3, and 4 of the Charge. Also, language related to "the supporting
criteria" in Item 1 should be eliminated.
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Response: This comment is not relevant to the working draft criteria document.
Specific Comments on Draft Outline for UAA
15.	1.3.2 - This item should be amended to remove the reference to "proposed water quality
standards". It should be replaced with "proposed designated uses" to accurately reflect
legal requirements and EPA policy.
Response: This comment is not relevant to the working draft criteria document.
16.	1.3.3. - This item should be removed entirely. A UAA is not a document which "assists
in the support of a variance". Instead it is a means of allowing less stringent designated
uses (which do not constitute an existing use) in certain narrow circumstances specified
in 40 CFR 131.10(g).
Response: This comment is not relevant to the working draft criteria document.
17.	1.4.3 - This item should be modified from "States Submit UAAs to Adopt New
Standards" to "UAAs for States to Consider when Adopting New Designated Uses".
States are not required, as the language implies, to submit a UAA for new standards and,
indeed, are prohibited by law, regulation, and EPA policy from submitting a UAA for
water quality criteria.
Response: This comment is not relevant to the working draft criteria document.
18.	Item 2 - Under the regulation at 40 CFR 131.10(g) social and economic factors are
separate, not merged as the language of the outline ('socioeconomic factors") states. For
a UAA to succeed under the regulation, "substantial and widespread economic and social
impact" must be shown. The outline should be rewritten to specify a separate social
factors analysis.
Response: This comment is not relevant to the working draft criteria document.
19.	5.2 - This portion of the outline ("Support for a Variance") is irrelevant to UAA analysis
and should be eliminated. A variance analysis for WQ criteria purposes must be, under
caselaw, federal statute and regulations, and EPA policy, separate from a UAA for
designated uses.
Response: This comment is not relevant to the working draft criteria document.
From Maryland DNR
All Maryland DNR's comments were specific to each criteria and the designated uses.
From Pennsylvania DEP
20.	We support this historic effort to establish scientifically based water quality criteria for
the Chesapeake Bay and its tidal tributary waters, and we support the multiple use and
seasonal approach underlying the development of these criteria.
Response: Good to hear such strong support from an important "upstream" Bay
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watershed partner.
21.	Because of the uniqueness and the importance of this effort, and because sections of the
draft proposal are yet to be completed or require additional analysis, we strongly agree
with your decision to provide at least two more opportunities for public review and
comment. This will enable all parties to evaluate the complete body of research and the
total decision-making process that was used to establish the criteria.
Response: In addition to the two more opportunities for public review, an
independent scientific peer review is planned in tandem with the second public
review in the winter time frame. During the state water quality standards adoptions
processes in Maryland, Virginia, Delaware, and the District of Columbia, there will
additional opportunities for public review and input prior to final adoption of the
Bay criteria and refined designated uses as state water quality standards.
22.	Although the working drafts represent significant progress toward development of lines
of evidence to be used in criteria establishment, the task of defining attainment is equally
critical. The documents list the key implementation procedures including the spatial and
temporal averaging of model output to be used in assessing attainment. However, the
methods used to develop the proposed criteria must be evaluated with respect to the
algorithms used by the Water Quality Model to calculate those same variables. Likewise,
the monitoring strategy must mesh with the needs of the Water Quality Model
(parameters, locations, scale) in determining attainment. Because the interpretations in
implementation are paramount to determining the true measure of the criteria and their
effect on Pennsylvania, we reserve the right to further comment on the contents of the
working drafts until such time as all the pieces are present and can be reviewed in concert
with one another.
Response: The revised draft criteria document contains extensive sets of
implementation guidelines tailored to each of the three sets of Bay criteria. Each set
of guidelines explicitly addresses how the monitoring data and model simulated
output should be applied in the determination of attainment of the proposed
criteria, whether for load allocation decision making or delisting of impaired
waters. The algorithms contained within the 2001 version of the Chesapeake Bay
water quality model for simulating estimates of water clarity are fully consistent
with the scientific underpinnings of the Bay water clarity criteria and how
attainment of these criteria is determined using monitoring data. The Bay water
quality model directly outputs estimates of dissolved oxygen and chlorophyll a as
two of its state variables. All these implementation guidelines and additional
supporting documentation are contained in the revised draft criteria document.
23.	References are made in these documents to "reductions beyond Tributary Strategy". As
the old Tributary Strategies are no longer valid, and new strategies will be developed
within the next two years, it does not seem appropriate to link nutrient/sediment
reductions to the old strategies/model scenarios called Tributary Strategy. These
parentheticals should relate the load reductions in the Low and High nutrient reduction
scenarios to the 2000 Projected/Progress scenario.
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Response: As recognized within the bold, all caps editor's notes within the working
draft criteria documents, the referenced scenarios were run using the 1998 version
of the Chesapeake Bay water quality model and prior versions of the tributary
strategy scenario. These model simulated results have been replaced with results
from a series of scenarios run using the 2001 version of the Bay water quality model
as described in more detailed in the revised draft criteria document.
For Future Consideration
24.	There is a section in the Recommended Implementation Procedures portion of each
document for the "factoring in" of naturally occurring violations of the proposed criteria.
Although it may be acceptable for a clarity criterion not to be met in the turbidity
maximum zone, high chlorophyll levels in poorly flushed embayments may be hard to
justify as exceptions. Also, if these areas of natural violation are delineated by the Water
Quality Model, some assurance must be made that model results from a "natural"
scenario are not over-stepping the bounds of the model calibration.
Response: These recommendations have been directly factored into the
implementation guidelines descriptions of naturally occurring criteria violations as
well as into the baywide use attainability analysis evaluation of natural water
quality conditions.
25.	We are particularly interested in how the established criteria will be translated into
acceptable nutrient loads for upstream non-tidal sources.
Response: The implementation guidelines include text describing the overall process
for translation of the Bay criteria attainment into allocation of loading caps to below
and above fall line sources.
From Wash-Cog
Implementation Issues
26.	We firmly believe that several of the proposed numeric values should be promulgated
as"guideline" or "target" values rather than ambient water quality criteria. More
specifically, we are concerned that two of the criteria (i.e. chlorophyll-a, water clarity) do
not yet have the accuracy and technical basis expected under Clean Water Act §304(a)for
promulgation as "criteria"-- and subsequent application as enforceable standards leading
to TMDLs and NPDES permit limits. Reasons for this conclusion are presented in the
report chapters. Further, if these values are given the status of criteria and become just
"other set of numbers" in a state standards table, recognition of the complex technical
basis of their development and their inherent uncertainty will be lost.
Response: See the responses to comments on the July 3, 2001 working draft
chlorophyll a and water clarity criteria documents for responses to concerns raised
in the above comment specific to these two criteria. These important Bay specific
criteria will NOT "just become 'other set of numbers' in a state standards table".
The revised draft Bay criteria document contains extensive implementation
guidelines as well as in-depth documentation on the scientific underpinnings of each
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of the three criteria. The development of the criteria and the resultant refined
designated uses were a commitment within the Chesapeake 2000 Agreement and
will be the basis for ultimately judging restoration of Bay water quality and
delisting tidal impaired waters. Such extensive political, technical and scientific
investments in the development and application of these Bay specific criteria and
recognition of the challenges ahead in restoring Bay water quality will not be lost in
the numbers.
27.	We are also concerned that several of the draft criteria values that are presented are not
attainable in many nearshore waters and estuarine embayments due to natural conditions,
and the costs of fully implementing these values as criteria could be enormous. We urge
the Working Groups and Bay Program Management to objectively assess the potential
for compliance (even in relatively pristine conditions), as well as the costs of compliance.
Response: The baywide use attainability analysis process now underway is where
the state partners will objectively balance potential social and economic impacts
with the requirement to restore Bay water quality through a process directly
involving public review and input. It is through the UAA process that
determinations will be made in terms of the ability to attain the proposed set of
refined designated uses.
28.	Rather than removing areas of the Bay from being categorized as "impaired" under
§303(d), we are concerned that establishing these values as numeric criteria (rather than
guidelines or targets) could do the opposite. Strict application of these values (e.g., tidal
freshwater chlorophyll-a values, instantaneous minimum Migratory Spawning and
Nursery DO values) will lead to hundreds of impairment listings, each legally requiring a
technically complex TMDL to be developed, and an enforcement strategy to resolve
water quality violations that may not be causing adverse effects on resident aquatic
communities. Forthcoming regulatory implementation language will be very important in
determining the effect of each of the draft criteria.
Response: The vast majority of the mainstem Chesapeake Bay and many of the tidal
tributaries and embayments are already listed on Maryland, Virginia, Delaware,
and the District of Columbia's list of impaired waters. The Bay criteria will
provide, for the first time, specific tidal Bay specific water quality measures for
defining when the impairments due to the negative effects of nutrient and sediment
overenrichment have been removed. The Chesapeake 2000 Agreement along with
the six state memorandum of understanding lays out a cooperative approach to
restoring Bay water quality by 2010 amongst all the Bay watershed jurisdictions.
Central to the success of this cooperative approach, which blends voluntary,
cooperative and regulatory programs together, is the adoption of the Bay criteria
into state water quality standards.
29.	Traditional ambient water quality criteria (e.g., copper, nickel) developed by U.S. EPA
are based upon single chemical toxicity tests conducted in the laboratory under controlled
experimental conditions, and then promulgated using a formal data evaluation approach
(U.S. EPA's 1994 National Guidelines). Using this EPA method, there is some degree of
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confidence about the uncertainty of the resulting numeric criteria. In our review of the
Chlorophyll-a and Water Clarity documents, however, there is no assessment of the
accuracy or uncertainty of the derived values. We believe it is important that the
uncertainty around each of the proposed criteria values be objectively evaluated to
determine whether the values are unnecessarily over- or under-protective of designated
uses. This effort should also include an objective assessment of the capacity of
Chesapeake Bay waters to comply with these values under current and reasonable future
management scenarios. If the suggested uncertainty analysis is conducted prior to
promulgation, this analysis might suggest these values should be issued as target values
rather than regulatory "criteria".
Response: See the responses to comments on the July 3, 2001 working draft
dissolved oxygen, chlorophyll a and water clarity criteria documents for responses
to concerns raised in the above comment specific to the three Bay criteria. As
discussed in these other responses to comments, the derivation of criteria addressing
eutrophication related impairments can not be derived strictly through "single
chemical toxicity tests conducted in the laboratory under controlled experimental
conditions, and then promulgated using a formal data evaluation approach".
Additional documentation on evaluations of and/or factoring in of uncertainties has
been incorporated into descriptions of the derivation of each of the three Bay
criteria.
30.	Although it is a useful exercise to review these draft documents strictly as scientific
reports, the implementation text (which is not yet available) will be critically important to
understanding the projected usefulness of the criteria in management decisions and the
effect of these values on the regional economy and the biological communities. Critical
implementation issues include: whether the values are promulgated as criteria or target
values; details of how compliance will be judged; how spatial and temporal variability
will be considered; as well as the duration and frequency assigned to each value.
Response: The revised draft criteria document contains extensive implementation
procedures and guidelines for review.
31.	Application and enforcement of these complex criteria will fall to the states. Each state
will be responsible for monitoring these multivariate parameters, developing basinwide
TMDLs for water quality parameters that can only be determined indirectly, and then
issuing enforceable permit limits to comply with these criteria (that vary seasonally and
spatially). To make it more complicated, it is unclear how short duration non-compliance
determinations in mainstem waters will be interpreted, how the cause(s) will be
evaluated, and which agency will have the responsibility to address it.
Response: The revised draft criteria document contains implementation procedures
and guidelines addressing these concerns.
32.	As currently proposed, a significant increase in monitoring would be required by the
states to implement the criteria, and to reliably determine attainment/nonattainment of
Chesapeake Bay segments. This increase would include specialized staffing, laboratory
analyses, and data management and interpretation.
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Response: The Chesapeake Bay Program's Monitoring and Assessment
Subcommittee is overseeing efforts currently underway to design a tidal monitoring
network, integrating both water quality and biological resource monitoring, to
collect the data necessary to directly measure attainment of the Bay criteria within
the tidal water designated uses. This network will involve significant enhancements
and changes to the current baywide monitoring program. The states are active
participants in the network design team charged with responsibility for bringing
forward a new tidal monitoring design by spring 2002. The reviewer is correct in
observing that this tidal network design will likely require more "specialized
staffing, laboratory analyses, and data management and interpretation" for fully
successful implementation.
33.	Finally, the proposed Chesapeake Bay criteria should not shift the burden to the states
and District to develop site-specific water quality standards or variances to resolve the
many applicability and non-compliance issues that result from issuing basin-wide
numeric criteria. Variances are rare and extraordinarily difficult to obtain. Site-specific
criteria represent a difficult regulatory/legal process that puts the burden on the discharge
community, and are subject to onerous state-specific administrative procedures and
endangered species requirements and formal review and approvals by U.S. EPA. If it is
determined that the proposed criteria might result in widespread non-compliance, then a
Bay-wide regulatory mechanism needs to be established to make the process manageable.
This could include initial promulgation as target values with a phase in period before
more refined numeric criteria are implemented.
Response: The entire process called for by the Chesapeake 2000 Agreement and the
six state memorandum of understanding is for all watershed jurisdictions and EPA
to work closely together in a coordinated manner to develop and implement a set of
Bay specific water quality standards, allocate loading reduction responsibilities, and
carry out implementation through cooperative means with a common goal in
mind-restoring Bay water quality by 2010. Integral to this process is the derivation
of a set of not only Bay specific, but designated use specific criteria. No where else
in the country are seven states and EPA working so closely together on such a wide
array of interconnected tools, criteria, standards, UAAs, policies, and allocations as
in the Bay watershed. The commitments and procedures are in place to prevent the
problems listed in the comment above given the continued commitment by all the
partners to the common goal.
From Maryland's Tributary Strategy Development Team
34.	The designated uses seem overly complex - complicated spatial and temporal variations.
Response: See responses to the July 3,2001 working draft designated uses document
for specific responses for each of the five proposed designated uses.
Concerns about implementation
35.	How will natural variations be addressed?
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Response: The revised draft criteria document contains extensive implementation
procedures and guidelines which address natural variations and determination of
criteria attainment in a host of circumstances.
36.	How will compliance be determined?
Response: The revised draft criteria document contains extensive implementation
procedures and guidelines which address the details of determination of criteria
attainment.
37.	How will goals be translated into standards?
Response: The opposite is what is happening, that is the state water quality
standards, currently in the form of draft Bay criteria and proposed refined tidal
water designated uses, will be used to set to define restored tidal water quality and
establish the new nutrient and sediment cap loads allocated down to the tributary
strategy subbasins.
38.	How will use attainability be handled? For example, Back River will never meet the
chlorophyll criterion.
Response: Attainability will be addressed through the baywide use attainability
analysis.
39.	Is chlorophyll a really required, or is it redundant with DO and clarity?
Response: See responses to similar comments in the responses to comments on the
July 3, 2001 working draft chlorophyll a criteria document.
Recommendations
40.	Set up an independent peer review, and refer peer review to STAC for oversight
Response: An independent peer review is planned in tandem with the second public
review cycle in the December-January time frame. Assistance from the Chesapeake
Bay Program's Scientific and Technical Advisory Committee in overseeing this peer
review process has been requested. The peer review process must also adhere to
EPA peer review requirements.
41.	Get Watershed Model loads out quickly. Tributary teams need to see the criterion-load
connection soon.
Response: We are working towards this end!
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