EPA Responses to

“External Peer Review of EPA’s ‘Proposed Methods and Approaches fo

Numeric Nutrient Criteria for Florida’s Inland Waters’”

Health and Ecological Criteria Division (4304T)

Office of Science and Technology

U.S. Environmental Protection Agency

1200 Pennsylvania Avenue, NW

Washington, DC 20460
This document summarizes EPA responses to the peer review comments on the proposed methods and approaches for d

nutrient criteria for Florida’s inland waters. The proposed methods document outlined the approaches being considered 

inland waters criteria and the feedback from reviewers was incorporated into the approaches used for deriving the draft 

document begins with a brief overview of the reviewers’ comments, a summary of EPA responses, and is followed by a m

reviewer comments and EPA responses.

Summary of General Comments

The document the reviewers were asked to review covered a variety of waterbody types and a variety of analytical topics

constructive and generally supportive of the technical proposals offered by EPA, with two reviewers commenting on the b

applauding the foundation being used for developing criteria. While some suggested analyses were recommended, for th

refinements rather than wholesale analyses that EPA had overlooked. To this extent, EPA was content that the majority o

were adequately considered. The reviewers focused on a number of very specific technical details, therefore, a general s

generate. As a result, each specific comment was addressed in turn in the matrix below. However, a few general concern

Some reviewers were concerned about the classification approaches used, specifically that fine scale geological/ecologica

lake regions were not incorporated. Moreover it was felt that some consistency among lake and stream classifications co

conducted. Other reviewers were not as concerned with the extent of overlap or with how refined classes were. One rev

concerned about the applicability to/protectiveness of fisheries conditions in many lakes with the criteria approaches pro

reviewer simply questioned the extent to which a variety of uses were considered. The majority of reviewers, however, d

issue of applicability of the criteria to specific uses. Another general concern raised by two reviewers was the effect of va

and their concern that it was not adequately addressed in the analyses selected, but most reviewers seemed to appreciat

variability in monitoring data is a reality routinely faced by agencies responsible for managing water resources. Another g

by one reviewer was the concept of site specificity and the issue of whether the approaches used would be adequate for 

whether site specific approaches would not be more adequate. Again, this was an issue raised specific to one reviewer. T

concern among reviewers was the organization and flow of the overall document, most felt that it could use tighter organ

amongst the chapter.
EPA Response to General Comments

EPA was very appreciative of the time and thoroughness of the reviews and their constructive and supportive tone. EPA 

the specific comments in the matrix below, which really represent the bulk of the comments. With regards to the genera

provides the following response:

• Classification Issue: With regards to classification, regional criteria derivation cannot account for every natural factor 

there is a trade‐off between adequately accounting for differences among natural drivers to reduce natural variability 

classification structure that can be implemented in a manner that is feasible within the resource constraints of water 

that end, EPA guidance recommends broad‐scale regional classification structures (e.g., ecoregions). The approach u

derivation for nutrients in Florida is consistent with these constraints and guidance recommendations. To the extent 

the classifications and their discussion, taking into account the reviewer concerns.

• Protectiveness of criteria for fisheries: The concern voiced over the potentially over or under‐protective nature of cri

be weighed against the responsibility of criteria to address aquatic life in general and not specific species. To a certai

addressed in use designation. Also of note is the issue that criteria must protect the most sensitive use and not only s

effort, the major focus was on aquatic life, but aquatic life in its totality and not specifically game fish.

• Variability: Data variability is a reality faced by water resource agencies. To the extent to which it can be reduced thr

classification, it is done. Even so, some variability cannot be completely removed and this variability influences criter

extent to which the criteria must protect uses. Most reviewers were cognizant of this issue and understand the const

monitoring data and its associated variability in criteria derivation.

• Site specificity: Regional nutrient criteria are not equitable with site‐specific criteria; however, the latter is always an 

where conditions warrant a site‐specific criterion. For regional criteria derivation, however, the resource constraints 

specific criteria are considerable. Most reviewers recognized this limitation and there was only one reviewer who rai

inland waters, although a second raised the concern for estuaries.

• Organization and flow: EPA shares the reviewers concerns on organization and flow and the draft technical support d

focused great effort on improving the organization, consistency, and flow.
Specific Comments and EPA Responses

The following text contains responses to the comments made by peer reviewers of the original USEPA 2009 document: Pr

Approaches for Developing Numeric Nutrient Criteria for Florida’s Inland Waters. The peer review comments are summa

2009 document entitled, “External Peer Review of EPA’s ‘Proposed Methods and Approaches for Developing Numeric Nu

Florida’s Inland Waters’. Peer Review Comments. Draft Final”.

Comment

Number Reviewer Question Document Chapter

Peer

Review

Document

Page

Summarized Comment/Edit E

1 Reviewer 1 1 General 3

Low nutrient standards do not favor

“fishable”

Of importance 

“fishable” to “s

called “interim

also their relat

goal, “restorat

physical and bi

There seems to 

fishable equate

In a sense, fish

not unhealthy 

harmful), fish a

from fish kills), 

safe to eat (un

Fishable does n

that everyone 

trophy‐size fish 

2 Reviewer 1 1 General 3

Florida Fish and Wildlife Conservation

Commission had no part in creation of

document

See response t
Comment

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3 Reviewer 1 1 General 3

As standards currently set, excellent

fishing and wildlife lakes will be

classified as impaired

A geological d

the classificatio

Classification m

parsimonious f

application, th

hyper‐refined may not be pra

implementatio

4 Reviewer 1 1 General 4

Geology is not well considered in lakes.

Lake morphology and hydrology

ignored, expand use of Vollendweider

Model (Section 14.2.1).

See comment 

5 Reviewer 1 1 General 4

Many approaches used in document to

define nutrient standards do not have

long‐term data to define true

background variance

The approache

available data 

6 Reviewer 1 1 General 4

Some form of long‐term variability

needs to be part of nutrient standard for

lakes

One way to inv

response is to 

as well. Modeconductivity firresiduals vs. nu

approach. This 

used with strea

natural predict

metrics. This a

considered, bu

data limitation
Comment

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7 Reviewer 1 1 General 4

40 PTU threshold for clear and colored

systems not ideal given natural Florida

lake color variability

A more geogra

better than us

absence, a long 

practicable. Serelated to colo

8 Reviewer 1 1 General 4

Approaches to setting standards used in

document should not be independent of

each other and application to different

waterbody‐types should be the same

Reviewer conc

organization awaterbody typ

TSD for EPA’s p

9 Reviewer 1 1 General 4

Use Griffith et al. 1997 methodology todevelop comprehensive Ecoregions

based on long‐term water chemistry

data in order to define normal

background variance

Fishability is un

swimming is ad

geological disc

the classificatio

Classification m

parsimonious f

application, th

hyper‐refined may not be pra

implementatio

10 Reviewer 3 1 General 6

Small samples sizes used in SCI and LVI

statistical analysis of macroinvertebrate

and vegetation (used to explainvariation within metric scores) limits

readability of nutrient noise.

See response t
Comment

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11 Reviewer 3 1 General 6

Report vague as to which SCI data used

in analyses and if data was subject to

filtering

This has been c

EPA’s propose

12 Reviewer 3 1 General 6

Change point analysis would serve as an

additional line of evidence supporting

observed relationships between nutrient

and biological metrics

This comment 

analysis was pu

addressed in th

proposed rule.

13 Reviewer 3 1 General 7

For Chapter 7, reference range approach

should be supplanted with an “all” sites

approach (as in Chapter 11)

This comment 

analysis was pu

addressed in th

proposed rule.

14 Reviewer 3 1 General 7

Longitudinal study of Steinhatchee and

Waccasassa basins and estuaries would

be more compelling if a nitrogen

enriched system was offered for

comparison

This was an FD

further conside

15 Reviewer 3 1 General 7

Chapter 9 basis for chlorophyll a

thresholds for lakes: report and

appendices vague as to which data used

and the strength and form of the

relationships forming TSI

See response t

9.
Comment

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16 Reviewer 3 1 General 7

Relationship between cyanobacteria and

chlorophyll a equivocal, real question is

whether increasing nutrient

concentration alters algal community

composition in a way that increases

probability of algal blooms

Composition d

17 Reviewer 3 1 General 7

Data used for Chapter 10 nutrient‐LVI

stressor‐response relationshipdemonstration should be used in change

point analysis as additional line of

evidence to support derived criteria

This comment 

analysis was pu

addressed in th

proposed rule.

18 Reviewer 3 1 General 8

The all sites chemistry data should be

paired with biological data and

reexamined within ranges of the

biological data

This comment 

analysis was pu

addressed in th

proposed rule.

19 Reviewer 3 1 General 8

Chapter 12, the applicability of

extrapolation of background nutrientconcentrations for streams questionable

This analysis w

not used for si

those expresse

the TSD for EPA

20 Reviewer 3 1 General 8

Multiple regression models in Chapter

13 offer more refined way to derive

criteria then conventional linear models

in Chapters 9 and 10

No response n
Comment

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21 Reviewer 3 1 General 8

Chapter 14, provide brief summary ofTMDLs with details of models as

appendices. Derived stream reach

concentrations in Table 10 should becompared to reference ranges.

Expression of uncertainty around

estimates should be provided.

This comment 

inland waters, 

incorporated icriteria develo

22 Reviewer 4 1 General 8

No synthesis component that considers

how various approaches fit together

Several review

to see a synthe

all the informa

proposed rule 

and integration

23 Reviewer 4 1 General 8

Should reconcile differences amongnumbers produced be each method

Several review

to see a synthe

all the informa

proposed rule 

and integration

24 Reviewer 4 1 General 9

Level of effort not uniform across

approaches

No response n

25 Reviewer 4 1 General 9

Provide more discussion on the interface

between science and policy

Several review

to see a synthe

all the informa

proposed rule 

and integration
Comment

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26 Reviewer 5 1 General 9

The proposal does not explicitly include

a second response parameter to

chlorophyll a for consideration and focus

Comment consanalyses addre

are presented 

proposed rule. a is principal re

variable.

27 Reviewer 5 1 General 9

Document does not consider stressors

other than TN and TP

Other stressor

extent provide

limitations of awas on nutrien

nutrient criteri

28 Reviewer 5 1 General 9

Provision for differential application ofcriteria, depending on conditions and

geography

Application do

but criteria do

ecological cond

weighed again

benefits impleweighed in the 

development.

29 Reviewer 5 1 General 10

South Florida estuaries are absent from

discussion and analysis

This comment 

into EPA’s estudevelopment e

estuaries are b

30 Reviewer 5 1 General 10

Models for downstream loading

calculations insufficient to assess

whether criteria protective of

downstream waters that do not receive

coherent mass flow

This comment 

into EPA’s estudevelopment e

models are be

extent practica
Comment

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31 Reviewer 5 1 General 10

Document lacks outline of the kinds of

data required to implement a nutrient

strategy

This is clarified 

proposed rule.

32 Reviewer 5 1 General 10

Include general caveat about the

hysteresis effect

This has been a

practicable giv

33 Reviewer 1 2 Ch. 3 11

IBI cannot account for variability in

anthropogenic impacts, and thus SCI,

LVI, and SDI wrong approach for setting

nutrient standards

The SCI, compoother metrics s

significant resp

Stressor‐respo

not used in the 

derivation for swas considered 

these analyses 

TSD Appendix 

34 Reviewer 1 2 Ch. 3 11

Any biological index that vary with

naturally occurring gradient will be of

little use in determining the extent of

anthropogenic impacts

See comment 

35 Reviewer 1 2 Ch. 3 11

Shortcoming of LVI is there is no metric

in it accounting for the total abundance

of aquatic plants in a lake system

This comment 

subsequent an

LVI. See the TS

rule.
Comment

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36 Reviewer 2 2 Ch. 3 12

SCI’s use in detecting nutrient pollution

only partially successful, being viable

only when a waterbody suffers from

chronic nutrient pollution. Acuteimpacts will be missed.

See comment 

37 Reviewer 2 2 Ch. 3 12

Invasive nuisance species do not require

excessive nutrients to proliferate and

the LVI will not reflect nutrient loading

This comment 

subsequent an

LVI. See the TS

rule.

38 Reviewer 2 2 Ch. 3 12

SDI is not useful for nutrient loading

assessment given Florida’s naturally

acidic waters

This comment 

subsequent an

SDI. See the TS

rule.

39 Reviewer 3 2 Ch. 3 13

Periphyton SDI still in developmental

stage for Florida waters

See comment 

40 Reviewer 4 2 Ch. 3 13

Distinction between reference and

impaired not clear. Experts conducting

site qualitative evaluations could not

agree on sites determined to be in the

middle of the BCG.

See comment 
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41 Reviewer 4 2 Ch. 3 13

Analysis used to support position that

“not reference” equals impaired

prejudges a policy decision regarding

attainment, which is not synonymous

with reference

See comment 

42 Reviewer 4 2 Ch. 3 14

Agrees with report that the SDI is “an

unreliable tool for assessing adverse

human effects on stream systems”

See comment 

43 Reviewer 4 2 Ch. 3 14

The sensitivity of diatoms to pH is a

strong confounding factor

See comment 

44 Reviewer 5 2 Ch. 3 14

Utility of SDI not clear at this point,

application to Florida untested and

requires further development

See comment 

45 Reviewer 1 3 Ch. 4 15

Approach used to set nitrate‐nitrite

criteria for streams only uses

concentration while total load of

nitrogen is not accounted for in different

systems

Incorporation 

practical given 

data. Howeve

in establishing 

values (see DP

TSD for EPA’s p

2).

46 Reviewer 2 3 Ch. 4 15

Review and cite peer‐reviewed

literature to add further scientific

validity and compliment existing "grey

literature" citations

This is more de

EPA’s propose
Comment

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47 Reviewer 2 3 Ch. 4 15

Include data on ammonia in springs ‐ if

low then proposed standard valid, if

high adjustments may be needed

Incorporation 

practical given 

data. Howeve

in establishing 

values (see DP

TSD for EPA’s p

2).

48 Reviewer 4 3 Ch. 4 16

The basis for the proposed lag time

between human population growth and

increasing nitrogen concentrations

should be strengthened

Incorporation 

practical given 

data. Howeve

in establishing 

values (see DP

TSD for EPA’s p

2).

49 Reviewer 4 3 Ch. 4 16

Provide documentation to support claim

"nitrate‐nitrite has been linked to many

of the observed detrimental impacts in

spring systems."

This has been c

EPA’s propose
Comment

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50 Reviewer 4 3 Ch. 4 16

The appropriateness of deriving criteria

based on studies of nuisance species

Lyngbya in a disturbed ecosystem not

discussed. Concluding that springs with

nitrate concentrations below a lab

determined threshold will support

native plant community is unsupported.Field surveys contain no information

about nitrate concentrations in springs

that support healthy native plant

communities.

See supporting 

criteria in the f

proposed rule.

51 Reviewer 5 3 Ch. 4 17

Expanding this analysis and protocol for

criteria development to all streamsystems may present difficulty with

transportability given the differences

between spring and stream systems

EPA agrees witeffect was con

criteria are not 

in the principa

52 Reviewer 5 3 Ch. 4 17

N inputs to streams may be more

detectable and controllable, which

argues for a different set of analytical

tools

EPA is unsure o

comment with 

nutrients. How

are not conside

principal criter
Comment

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53 Reviewer 5 3 Ch. 4 17

Based on data presented, both the

nuisance macroalgae and "excessive"

algal growth criteria suggest a TN

threshold closer to 0.23 mg/L to more

effectively provide a margin of safety

When weighin

EPA decided o

concentrations 

for EPA’s propo

given the addit

considered.

54 Reviewer 5 3 Ch. 4 17

p. 49: Conservative target concentrationshould be 401 instead of 420 ug N/L

See response t

55 Reviewer 5 3 Ch. 4 17

p. 49: Inconsistent use of unitsdistracting, concentrations should all beexpressed in micrograms.

This is clarified 

proposed rule.

56 Reviewer 5 3 Ch. 4 17 p. 51: why 0.23 is unnecessarily protective is not made clear See response t57 Reviewer 5 3 Ch. 4 17

Figure 4‐12: Why is the increase evident

above 0.24 mg/L disregarded? The lower

threshold is being set a too high a

concentration

See response t

58 Reviewer 1 4 Ch. 5 18

Strongest section of document, broaden

this approach to other sections

No technical re

59 Reviewer 1 4 Ch. 5 18

Combining all available data and

refining Griffith et al. (1997) lake regions

best approach

See comment 
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60 Reviewer 2 4 Ch. 5 18

Include information on "nutrient

reference streams/sites" criteria in Ch.5

This concern is 

EPA’s propose

61 Reviewer 2 4 Ch. 5 18

Not explained why Everglades region

not addressed

The Everglades 

and have been criteria docum

62 Reviewer 2 4 Ch. 5 18

The TN stream nutrient regions need to

be mapped

This concern is 

EPA’s propose

63 Reviewer 5 4 Ch. 5 19

Not clearly explained how ecoregion

approach and biological taxonomy

approach were used in support of

nutrient approach

Ecoregion and contribute to t

Comment consclarified in the 

rule.

64 Reviewer 5 4 Ch. 5 19

A disproportionate amount of the

document dedicated to the means by

which the western peninsula is split into

two ecoregions

No technical re

65 Reviewer 5 4 Ch. 5 19

The discussion of regionalization based

on TN is barely mentioned.

This concern is 

EPA’s propose

66 Reviewer 5 4 Ch. 5 19

No discussion on how the southern

portion of Florida would be subdivided

Southern Florid

developed in t

proposed rule.

67 Reviewer 5 4 Ch. 5 19

Further detail on state‐wide

regionalization required

This concern is 

EPA’s propose
Comment

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68 Reviewer 5 4 Ch. 5 19

p. 61: The statement that bioregions

were not sufficiently homogenous with

regard to nutrient concentration has no

backup

This concern is 

EPA’s propose

69 Reviewer 5 4 Ch. 5 19

What were the criteria for homogeneity

and why?

See response t

70 Reviewer 5 4 Ch. 5 19

The alternatives based on a slew of

variables are not well defined nor is a

justification provided for their use

This concern is 

EPA’s propose

71 Reviewer 5 4 Ch. 5 19

How will the disparate regionalizations

between N and P driven be reconciled to

each other and to the biogeography?

This concern is 

EPA’s propose

72 Reviewer 5 4 Ch. 5 19

It would be useful to understand how

the regionalization will be incorporated

into the overall process of criteria

development here as part of the chapter

describing the classification framework

itself.

This concern is 

EPA’s propose
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73 Reviewer 1 5 Ch. 6 20

Best approach to evaluate biologicalstressor‐response is to make sure toseparate streams into ecoregionsbased on geology, hydrology andphysiography then develop the bestmodels relating biological measures

to physical factors of the stream andcompare the residuals of thesemodels to nutrient concentrationswithin ecoregions

EPA considered 

comments 3, 6

74 Reviewer 2 5 Ch. 6 20

Using benthic taxa to assess nutrient

impacts can at best provide partial

guidance

See comment 

75 Reviewer 2 5 Ch. 6 20

The authors need to add to Figure 6‐1

the r2 and p values, so the reader can

see the individual statistics associated

with the relationships

Valid commen

response appr

were not used 

development. 

been considere

76 Reviewer 2 5 Ch. 6 20

First paragraph on page 73 – why would

% very tolerant taxa show an adverse

response to increasing N?

Valid commen

response appr

were not used 

development b

variable respo

33.
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77 Reviewer 2 5 Ch. 6 20

In addition to searching for nutrientcriteria, it is useful to determine

nuisance levels of periphyton biomass

that can afflict streams

Final criteria w

stressor‐respolimitations of d

relationships. 

TSD for EPA’s p

78 Reviewer 2 5 Ch. 6 20‐21

Additional approaches: Dodds et al.

1998 and Dodds et al. 2002; Mallin et al.

2001, 2002, and 2004 (nutrient additionbioassays conducted on stream water

for various ecoregions)

Final criteria w

stressor‐respo

limitations of d

relationships. 

TSD for EPA’s p

79 Reviewer 2 5 Ch. 6 21

There are heterotrophic responses to

nutrient loading that are not usually

measured or even considered

Data on hetero

not available.

80 Reviewer 3 5 Ch. 6 22

The regressions involving the SCI and SDI

(and/or their component metrics)

appear confounded by multicollinearity

See comment 

81 Reviewer 3 5 Ch. 6 22

For the purposes of examining effects‐

based relationships, NOx and ammonia

nitrogen should not be combined into a

single variable, as the two are measuring

different aspects of the pollutiongradient

There was insuseparate the N 

guidance focus
Comment

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82 Reviewer 3 5 Ch. 6 22

NOx should be included in the

regressions in lieu of other expressions

of cross‐correlated nitrogen given the

work presented in Chapter 4

There was insuseparate the N 

guidance focus

83 Reviewer 3 5 Ch. 6 22

Change point analysis along a NOx

gradient should be done using the

residual variation in biological metrics

following regression on conductivity,

color and ammonia nitrogen

Proposed crite

stressor‐respolimitations of d

relationships, b

conducted. Th

for EPA’s propo

84 Reviewer 3 5 Ch. 6 22

Wide confidence intervals resulting frombootstrapping during change point

analysis should not be construed as a

limitation, but rather the median changepoints found for each metric should be

considered in aggregate

Proposed crite

stressor‐respo

limitations of d

relationships, b

conducted. Th

for EPA’s propo

confidence int

indicators of la

points (See Qia
Comment

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85 Reviewer 3 5 Ch. 6 23

Quantile regression applied to wedge‐

shaped data sets should be used to

identify a subset of data that is

responding to a gradient of interest.

The two data sets can then be compared

to help understand the secondary

gradients, and to perform direct

gradient analysis on the data that are

relatively less influenced by the

secondary gradient(s).

Proposed crite

stressor‐respolimitations of d

relationships, b

conducted. Th

for EPA’s propo

86 Reviewer 3 5 Ch. 6 23

The report is vague with respect to

which data are used for the SCI

regressions

Proposed crite

stressor‐respo

limitations of d

relationships, b

conducted. Th

for EPA’s propo

87 Reviewer 3 5 Ch. 6 23

The sample size of ~ 75 appears rather

small

Analyses could 

the extent prac

limitations.

88 Reviewer 3 5 Ch. 6 23

Were these data collected prospectively

along a nutrient gradient, randomlyselected, or the result of a data cull to

remove spurious sites from existing data

A combination 
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89 Reviewer 5 5 Ch. 6 24

The analysis of dose‐responsecharacteristics of nutrient enrichment

on macroinvertebrates, periphyton

abundance and chlorophyll a

concentrations yielded ambiguous

results. The high degree of variability in

the relationships rendered theestablishment of well‐constrainedquantitative relationships untenable.

See comment 

90 Reviewer 5 5 Ch. 6 24

It is likely that the utility of applyinganalysis of macro‐invertebrates inrelation to nutrients to determinedose‐response curves that can beused to establish quantitative criteriais of dubious value

See comment 

91 Reviewer 5 5 Ch. 6 24

Looking at higher trophic levels as afirst cut and as a means to determinenutrient criteria is not likely to beeffective beyond its utility as ascreening tool

See comment 
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92 Reviewer 1 6 Ch. 7 24

Has a problem with setting upreference benchmarks within regionsdue to the large amount of varianceassociated with any biological and/orwater chemistry measurements

Benchmark disEPA’s propose

variance conce

selected perce

in the TSD for 

93 Reviewer 1 6 Ch. 7 25

The selection process listed inChapter 7 could cause theelimination of lakes from the database that are truly not impacted andit could also cause the selection of

rivers that are unique and not reallyrepresentative of the individualEcoregion

Benchmark disEPA’s propose

approach, is ou

EPA’s propose
Comment

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94 Reviewer 1 6 Ch. 7 25

Recommend an approach ofmodeling what factors account for

the most variance in biologicalmeasures and nutrients

concentrations within individualEcoregions and the plot the residual

against measurements of potentialof anthropogenic impacts (LDI). Anyrelations or break points betweenthe residuals and measures ofpotential anthropogenic impacts mayhelp point to a nutrient standard.

Developing mo(diatom) bio an

nutrient condit

the FDEP SDI dattractive, the 

as their base a 

natural, refere

and pH of the s

extended to la

that appropria

exist to develo

95 Reviewer 2 6 Ch. 7 25

Define WBID up front in this chapter This was done 

proposed rule.

96 Reviewer 2 6 Ch. 7 25

As to natural variability in abenchmark stream, one aspect that

may not have been considered istidal action in freshwater streams

Benchmark disEPA’s propose

variance conceselected perce

in the TSD for 
Comment

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97 Reviewer 2 6 Ch. 7 25

Streams in Florida can have naturally

low pH and DO conditions and thusthese waters should not be excludedas reference sites

Benchmark disEPA’s propose

variance conceselected perce

in the TSD for 

98 Reviewer 3 6 Ch. 7 26

A careful examination of the sites where

good biology and high nutrient levels

intersect should be done with an eye

toward identifying mitigating factors like

canopy cover, local stream gradient (i.e.,

slope), substrate composition, the form

of nutrient resulting in the high

concentration (e.g., wetland‐derived

nitrogen vs. nitrate from groundwater),

etc.

See response t

99 Reviewer 3 6 Ch. 7 26

Need to examine the distributions ofnutrient concentrations withincategorical ranges of the SCI (or

some other biologicalmeasure/metric) for benchmark sites

and for all sites by region

See response t

addition, EPA ithe proposed a

100 Reviewer 4 6 Ch. 7 26

Setting the threshold at 0.35 mg/L

presumes adoption of the proposed

criterion

No technical re
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101 Reviewer 4 6 Ch. 7 26

The exclusion of sites with SCI <40

reflects the assumption, alreadymentioned above, that impaired equals

“not reference.”

An in‐depth an

associated wit

thresholds is in

EPA’s propose

102 Reviewer 4 6 Ch. 7 26

Reservations about equating

“representativeness” with a

minimization of variability in the

benchmark set

No technical re

103 Reviewer 4 6 Ch. 7 26

Exclusion of nutrient outliers is troubling

as they improve the representativeness

of the remaining sites

Outlier analysi

documented a

for EPA’s propo

104 Reviewer 5 6 Ch. 7 27

Weaknesses include: Lack ofmechanistic understanding of

processes underlying the patterns,lack of predictability, lack of inclusionof far field effects downstream

No technical re
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105 Reviewer 5 6 Ch. 7 27

Continued assessment of theeffectiveness of these criteriathrough standardized performancemeasures is critical in determiningvalidity. Performance measures arenot considered in this document andit is a recommendation that arigorous protocol of evaluation beimplemented.

No comment n

technical deriv

106 Reviewer 1 7 Ch. 8 27

This nutrient longitudinal studyfocuses on only nutrientconcentrations and not nutrientloads

Analysis from tconsidered in tderivation.

107 Reviewer 1 7 Ch. 8 28

Adding the data that has alreadybeen collected to discharge valuesand using the Vollenweider approachdescribed in Section 14 would allowthe prediction of the change in thenutrient concentration of the riverneeded to cause a significant changein the bays

Analysis from tconsidered in tderivation.
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108 Reviewer 3 7 Ch. 8 28

It would be really helpful to meld theresults of Chapter 8 with those of

Chapter 14, including doing a modelof nitrogen loading for the

Waccasassa and Steinhatcheeestuaries for comparison (andvalidation) to the others presented inChapter 14

Analysis from tconsidered in dcriteria. In add

criteria effort i

revision and al

the estuarine c

impact DPV.

109 Reviewer 3 7 Ch. 8 29

A description of the condition ofseagrass beds in the estuaries listed

in Table 10 in Chapter 14 should be

compared to those for theWaccasassa and Steinhatchee forcontext

See response t

110 Reviewer 4 7 Ch. 8 29

Although the longitudinal studies

showed that the two rivers and tworeceiving estuaries are minimally

disturbed, I would hesitate toconclude that they constitute proofof concept

See response t

111 Reviewer 4 7 Ch. 8 29

It does not seem practical on astatewide basis to derive streamcriteria that are uniformly protectiveof uses in every estuary

See response t

estuarine protgenerally estua

extent allowed 
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112 Reviewer 4 7 Ch. 8 29

Criteria should be set separately forstreams and estuaries (or lakes) tobe protective of uses in each system

See response t

Separate criterbeing develope

regulations, up

also, however, of downstream 

standards.

113 Reviewer 5 7 Ch. 8 29

The window on the subject is somewhat

limited here as the two estuaries

selected are in the same geographic

area, the same bioregion, the same

nutrient region, etc.

No technical re

114 Reviewer 5 7 Ch. 8 29

The analysis is minimal in the extreme.

The supporting evidence of an

unimpacted fishery, its description or its

history is non‐existent. There is no

exposition of the type of seagrass in the

downstream receiving waters, the SAV

density, condition, its antecedent

history, or documentation of any change

over time.

See response t

115 Reviewer 5 7 Ch. 8 30

Such assessments might be considered

more a screening tool

No technical re
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116 Reviewer 5 7 Ch. 8 30

There are many factors, assumptions

and questions that remain untested by

this pilot study

No technical re

117 Reviewer 5 7 Ch. 8 30

General understanding of estuarine

circulation and coastal water mass

transport, if not outright circulation

modeling, will be required in many cases

for true assessment of nutrient fate and

transport and downstream effects

See response t

118 Reviewer 5 7 Ch. 8 30

Non‐linear response of downstream

systems to upstream inputs may result

in rapid crossing of thresholds or tipping

points earlier in the nutrient loading

trajectory than expected

See response t

comment is be

ongoing estuar

development b

alternative end

119 Reviewer 5 7 Ch. 8 30

Each distinctive water body (stream,lake, estuary, spring, river) should be

assessed in its own context for

response to nutrient criteria

See response t

Separate critereach waterbodaddress downs

120 Reviewer 1 8 Ch. 9 30

Trophic state scale as originally defined

is a gradient without a real break point

so I have always had difficulty with one

individual chlorophyll number as a

standard

No technical re
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121 Reviewer 1 8 Ch. 9 30

Color can become a problem with this

proposed chlorophyll standards because

with one rainfall color can change from

low to high with one rainfall shifting the

chlorophyll standard from 10 to 20 μg/l

which is a huge difference

See response t

122 Reviewer 1 8 Ch. 9 30

Using specific conductance to get at

differences based on geology is

conceptually a good idea but there are

many lakes in Florida near the coast that

have high specific conductance because

of saltwater interferences

See respond to 

123 Reviewer 1 8 Ch. 9 31

Proposed chlorophyll standards also do

not take into account the abundance of

aquatic plants within individual lakes

Aquatic plants 

vis the LVI inde

be a poor resp

chlorophyll tar

on these comm

detailed in the 

rule.
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124 Reviewer 1 8 Ch. 9 31

Almost all of Florida’s exceptional fishing

lakes would have chlorophyll

concentrations exceeding 20μg/L

making them impaired on paper. This is

one reason why I mentioned in my

general comments that Florida Fish and

Wildlife Conservation Commission needs

to be involved with setting nutrient

standards

See response t

125 Reviewer 1 8 Ch. 9 31

The approach the reviewer liked the

most that was reviewed in the

document is the one taken by Alabama

of maintaining the existing condition.Taking the abundant long‐term data that

is now available and defining normal

background variance would be a good

way to setting a chlorophyll standard.

Long‐term dat

few lakes in Flo

larger regional 

applicability of Revisions to th

were made ba

comments. Th

in the TSD for 

126 Reviewer 2 8 Ch. 9 31

As to the use of paleolimnological

studies – reviewer does not support

their use to set numeric criteria

These studied 

criteria but we

it. The revision

TSD for EPA’s p
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127 Reviewer 2 8 Ch. 9 32

As to biological responses, DEP should

consider what would be the impact of

chlorophyll a on biochemical oxygen

demand, potentially developingregression equations for BOD as

response variable to chlorophyll a

Data limitation

development odescribed.

128 Reviewer 3 8 Ch. 9 32

A presentation of how the equations

listed on page 126 were derived (scatter

plots, statistical output, etc.) would have

been helpful

The revisions b

are detailed in 

proposed rule.

129 Reviewer 3 8 Ch. 9 32

The section relating cyanobacteria

abundance to chlorophyll a levels

offered little towards understanding

effects of nutrient enrichment. A better

approach would be, where data are

available, to look at trends in

cyanobacteria abundance over time for

selected lakes where nutrient

concentrations have increased.

Data limitation

development odescribed.

130 Reviewer 3 8 Ch. 9 32

The results from Chapter 9 should bemelded with those from Chapter 10

This comment 

TSD for EPA’s p

the suggestion
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131 Reviewer 4 8 Ch. 9 33

It is not clear what role expert opinion

(i.e., what other states have done)

should play in view of the other options

available, unless it is a matter of seeking

reassurance in similar conclusions

No comment n

132 Reviewer 4 8 Ch. 9 33

Information attributed to Colorado is

mistaken because no proposals have

been made yet for nutrient criteria

This comment 

TSD for EPA’s p

the suggestion

133 Reviewer 4 8 Ch. 9 33

Criteria developed for fishery support

may not be uniformly compatible with

all uses in other states

No technical re

134 Reviewer 4 8 Ch. 9 33

What approach would Florida take to

balance fishery and aesthetic

considerations if these were found to be

in conflict?

See response t

135 Reviewer 4 8 Ch. 9 33

Maintenance of existing conditions:applicable to site‐specific criteriadevelopment, difficult to see how it

would address use protection on the

statewide level

No technical re
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136 Reviewer 4 8 Ch. 9 33

The [lake] reference approach ismentioned only briefly in thechapter. Supporting materials show

that much effort was invested in thisapproach, which also producedrecommendations for nutrients andtransparency. However, asmentioned above, development ofcriteria with this approach would

have to be reconciled with thepaleolimnological information.”

This comment 

lake criteria de

clarify and the 

rule reflect the 

137 Reviewer 5 8 Ch. 9 34

The 90th percentile of reference

conditions for nutrient criteria is a

reasonable alternative but the evidence

for its use is not presented in this

chapter

Benchmark pe

lakes was not u

derivation.

138 Reviewer 5 8 Ch. 9 34

p. 124: Note misleading sentencestructure: Florida lakes do not havecool‐water fisheries (true) but do

have oxygenated hypolimnia(contrary to the implication)

Edits made to 
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139 Reviewer 1 9 Ch. 10 34

Concerned and not sure we have the

ability to easily classify lakes into the

color and/or conductivity groups that

are being recommended

See response t

140 Reviewer 1 9 Ch. 10 34

Using Okeechobee color data as any

kind of a model for other lakes in the

state is not appropriate because there

are no other lakes in the state like

Okeechobee

Final analysis d

lake for criteria 

141 Reviewer 1 9 Ch. 10 34

Using 40 PCU as the cut off for colored

and clear lakes can be a difficult

boundary to really define

See response t

142 Reviewer 1 9 Ch. 10 34

Much more work needs to be done with

long‐term data to better define the lake

groups based on color and conductivity

See responses 

143 Reviewer 2 9 Ch. 10 36

p. 135, line 5; it states that lake

vegetation exhibited a significant

adverse response to nutrients. Actuallyit was a positive response (though

weak).

Lake vegetatio

used in derivin

based in part o

this comment.
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144 Reviewer 2 9 Ch. 10 37

The 9 μg/L response criterion for the

clear, low conductivity lakes is too high.

Would favor a chlorophyll a response

criteria of 5 μg/L for clear, low

conductivity Florida lakes.

No technical re

145 Reviewer 3 9 Ch. 10 37

Using the residuals of the LVI following

regression on color and conductivity in

change point analysis over a gradient of

TN or TP should be tried

See response t

146 Reviewer 3 9 Ch. 10 38

Evaluate the proposed classification and

sub‐classification approach for lakes: a

separate slopes regression model would

help here

See response t

147 Reviewer 4 9 Ch. 10 38

It is not clear what action would betaken if chlorophyll is within bounds,

but one or both nutrients exceed theupper threshold (lower predictioninterval)

The comment 

implementatio

proposed rule 

148 Reviewer 4 9 Ch. 10 38

Clear and colored categories: it is notapparent if all lakes can easily besegregated into those two groups, orif there is an unbroken continuum oflakes

See response t
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149 Reviewer 4 9 Ch. 10 38

Less information is presentedregarding the merits of conductance

as an additional classification

variable

This comment 

language regar

conductivity w

the concern. H

was not used i

150 Reviewer 4 9 Ch. 10 38

It might be interesting to learn moreabout the TAC’s reasoning regardingthe 100 umho/cm dividing line, butreviewer doesn't have any particular

reservations about accepting theirconclusion

No technical re

151 Reviewer 4 9 Ch. 10 38

For the independent approaches fordevelopment of criteria based on

chlorophyll or lake vegetation, arethe two approaches drawing on thesame set of lakes?

Where data wewill have provi

152 Reviewer 4 9 Ch. 10 38

A plot of chlorophyll vs. LVI helpful See response t

153 Reviewer 5 9 Ch. 10 39

When data show that nutrients are

within in compliance of established

criteria, yet chlorophyll a criteria are

exceeded, then one would expect that

nutrient reductions would have to be

undertaken

See response t
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154 Reviewer 5 9 Ch. 10 39

Recommendation for investment in

additional research into ecologicalrelationships and evaluation ofsystems or classes of systems andtheir driving processes

No technical re

155 Reviewer 1 10 Ch. 11 40

Ecoregion concept to form the basefor analyses is a good start thatneeds to be used throughout thedocument

See response t

Regionalization 

and then were 

appropriately. 

was not used a

proposed crite

156 Reviewer 1 10 Ch. 11 40

Physical factors dominate mostaspects of stream biology andovershadow impacts of nutrients. Forthis reason the reviewer had a hardtime with this approach to settingstandards

See response t

157 Reviewer 1 10 Ch. 11 40

No matter what percentage of thedata distribution you use for astandard, some streams that are

meeting use and functioning fine will

be considered impaired

Analysis and te

associated wit

presented wer

EPA’s propose

analysis was no

the proposed c

158 Reviewer 2 10 Ch. 11 40

The outlier removal process could use a

bit of tweaking

See response t

streams analys

basis for the pr
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159 Reviewer 2 10 Ch. 11 40

Concerned about using TN of 100 mg/L

and TP of 15 mg/L as screening

thresholds, these thresholds are to high

Screening thre

appropriately, 

to comment 10

was not used a

proposed crite

160 Reviewer 2 10 Ch. 11 40

DEP kicked out data when therewere 4 or less observations within ayear. However, a lot of variabilitycan occur with only 5 or 6 samples aswell, both seasonal and event‐driven. Reviewer suggested drawingthe line at 8 observations or less asyear as a cutoff point for data sets.

Drop loss of 8 

and analysis cofinal rules were 

criteria. All str

used as the ba

criteria.
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161 Reviewer 3 10 Ch. 11 40

Descriptive statistics are necessaryfor a broad understanding of systemsat the population level. However, thereference approach, in the absence

of biological data, provides theweakest line of evidence for criteriadevelopment. The all sites chemistrydata should, emphatically, be pairedwith biological data (i.e., the SCI, SDI,or a sensitive component metric) andreexamined within ranges of thebiological data.

The revised ap

biologically he

streams analysbasis for the pr

162 Reviewer 4 10 Ch. 11 41

Because reference (or minimally

disturbed) sites seem readily available in

Florida, there is little motivation to use

the all streams approach. It is notreassuring to know that “the 25th

percentile from the All Streams data was

less than the 75th percentile ... from the

Benchmark data set.” Some reference

sites still will be classified as impaired.

The revised ap

biologically he

streams analysbasis for the pr
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163 Reviewer 5 10 Ch. 11 41

This is a spare chapter that presents

data without significant analysis. The

information presented here is lacking

recommendation or interpretation.

The all streams 

exploratory an

as the basis for 

164 Reviewer 5 10 Ch. 11 41

It would have been an improvement to

present actual shapes of nutrient

concentration frequency distributions

graphically, and specifically with the two

alternative approaches overlain for each

nutrient for each nutrient region

This analysis w

in deriving fina

streams analys

exploratory an

as the basis for 

165 Reviewer 5 10 Ch. 11 41

The next step that would have been

anticipated was not taken here‐ that is

relating the nutrient thresholds as

calculated using All Streams to various

estimates of stream condition as was

done for the other alternatives, dose‐

response and nutrient benchmark

distributional approach

This analysis w

in deriving fina

streams analys

exploratory an

as the basis for 
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166 Reviewer 2 11 Ch. 12 41‐42

Chapter 12 citations of tables and

figures did not match the ones supplied.

It was assumed Table 1 is actually Table

12‐5, Figure 1 is Figure 12‐3, Figure 2 is

12‐2, and Figure 4 is 12‐4.

No technical re

167 Reviewer 2 11 Ch. 12 42

Regarding the 9% increase between

1995 to 2004, it can be safely assumed it

is due to increased landscape

development

No technical re

168 Reviewer 4 11 Ch. 12 42

It seems unfair to say that the Dodds

and Oakes method didn’t work

(“candidate nutrient criteria could not

be reliably derived using the Dodds and

Oakes (2004) methods as applied here

with the available data”); it was not

given an adequate test because, as

stated in the report, the required data

were not available

In part, the we

is based on lac

analysis was nocriteria derivat

169 Reviewer 4 11 Ch. 12 42

The effort to derive background

conditions based on the LDI relationship

seemed perfunctory in view of the very

promising results presented previously

in the report

See response t
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170 Reviewer 1 12 Ch. 13 43

Reviewer not comfortable with setting

standards based on a percentage of a

distribution of data. There are too many

lakes that are functioning well and

meeting uses that will be considered

impaired.

Final lake crite

stressor‐respodownplay distr

171 Reviewer 1 12 Ch. 13 43

Without more work on long‐term color

data in lakes, reviewer is uncomfortable

with the separation of lakes into colored

and clear lakes based on a measured

color of 40 PCU

See response t

172 Reviewer 2 12 Ch. 13 43 Editing remark – page 175, middle, Figure 2 should read Figure 13‐3 No technical re173 Reviewer 2 12 Ch. 13 43

p. 182 – there are some issues with the

Outliers and Invalid Data. Nitrate is

kicked out if it is above 75 mg/L, yet TN

is kicked out if it is above 20 mg/L – a

disconnect here. DEP needs to bring this

expulsion criterion for TN down to 20 or

25 mg/L.

These concern

into subsequen
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174 Reviewer 2 12 Ch. 13 43

As to chlorophyll a, the highest level

seen by the reviewer in a bloom is 400

μg/L, while DEP is using 1,000 μg/L as a

criterion. Suggest cutting that way down

to at least < 400 μg/L.

The multiple li

approach was 

proposed crite

175 Reviewer 2 12 Ch. 13 43

As to Secchi depth, not aware of Florida

lakes that are 50 m deep, so why use a

Secchi of 50 m to kick out an outlier?

How about 10 m?

The multiple li

approach was proposed crite

176 Reviewer 2 12 Ch. 13 43

Suggest using a lower limit of 8 samples

in a year to create a mean, with samples

taken seasonally to collect lower‐impact

periods as well.

See response t

177 Reviewer 4 12 Ch. 13 44

Placement of the diagonal line (now set

to the “average ratio between ln (TN)

and ln(TP)”) deserves more attention

because it makes an important

statement about the nutrient regime. .

The ratio used in the graph (0.588/0.013

= 45:1) is very high and indicative of a

phosphorus‐limited situation.Placement of the diagonal line might be

adjusted according to expectations for a

particular region.

This concern w

in the final ana

analysis used tmultiple linear 

was not used i

criteria for lake
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178 Reviewer 4 12 Ch. 13 44

Why are the distributional statistics for

lakes determined on a statewide basis

when there are identifiable geographic

patterns for phosphorus and nitrogen in

streams?

Distributional s

in deriving the 

179 Reviewer 5 12 Ch. 13 44

It is curious that the entire pooled

dataset in figure 13‐4 shows individual

lakes within the pool seem to trend to a

lower slope than the slope of all pooled

observations. This is not discussed in

the text.

Slope compari

subsequent an

in the TSD for 

180 Reviewer 1 13 Ch. 14 45

Modeling efforts accomplished in

Section 14 should be done using

phosphorus instead of nitrogen.

P was analyzed 

both nutrients for EPA’s propo

181 Reviewer 2 13 Ch. 14 46

p. 188: “in the absence of more specific

information it may be appropriate to

reduce the anthropogenic contribution

of the TN load to estuaries by a constant

fraction.” This is not appropriate. Thereis no “one size fits all” solution for

ecological problems such as this.

In the absence 

uptake parameestimates have 

Estuarine mod

to update as m

characteristics 
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182 Reviewer 2 13 Ch. 14 46

14.1.18 ‐ Another concern I have is thatof the contribution of septic systems to

the nutrient load in estuarine waters.

While DEP certainly accounts for direct

point source contributions of nutrients

to estuaries in their models, it is known

from research in the Carolinas that

nutrients from septic systems directly

enter estuarine waters as well (Cahoon

et al. 2006).

This comment 

subsequent an

EPA’s propose

will also be inc

subsequent esthe extent prac

183 Reviewer 2 13 Ch. 14 47

The tide is an important consideration in

obtaining accurate measures of nutrient

loading to downstream waters.

This comment 

subsequent an

EPA’s propose

will also be inc

subsequent es

the extent prac

184 Reviewer 3 13 Ch. 14 47

The approach would be more

compelling if the examples for intact

systems (as previously noted) were

included for comparisons

No technical re

185 Reviewer 3 13 Ch. 14 47

It would have been nice to see the

Vollenweider example worked out for a

few lakes.

The example p

average lake co

represents the 

majority of Flo
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186 Reviewer 4 13 Ch. 14 48

While there is no conceptual reason why

the model could not be applied to lakes

as well as estuaries, there may be a

practical limitation to the lower bound

on geographic scale

No technical re

187 Reviewer 4 13 Ch. 14 48

There is a fundamental question about

linking attainment in estuaries with

attainment in tributary streams.

No technical re

188 Reviewer 4 13 Ch. 14 48

For SPARROW, it is not clear if the

linkage includes contributions of

nitrogen generated by the marsh

grasses within the estuary.

This comment 

subsequent an

TSD for EPA’s p

clarification on 

SPARROW mod

also be incorpo

estuarine critepracticable.

189 Reviewer 4 13 Ch. 14 48

The section on lake modeling is so brief

that it is hard to evaluate

The TSD for EP

more expande

section.

190 Reviewer 4 13 Ch. 14 48‐49

Just like estuaries, there is a

fundamental issue about the linkage

between concentration‐based standards

in lakes and in the tributary streams

No technical re
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191 Reviewer 5 13 Ch. 14 49

While the model shows promise as a

tool for estimating N loads to many

Florida estuaries, it is important to note

that several Florida estuaries would be

inappropriate as targets for SPARROW

modeling. Large interaction of surface

flows with groundwater flows, the lack

of mass flow or well‐constrained point‐

source input, and multiple ungauged

inputs would render such modeling

ineffective.

This comment 

subsequent an

TSD for EPA’s p

clarification on 

SPARROW mod

also be incorpo

estuarine critepracticable, an

are being consSPARROW.

192 Reviewer 5 13 Ch. 14 49

There is a need also to evaluate the

spatial heterogeneity of receiving

waters, particularly in estuaries

This comment 

subsequent an

EPA’s propose

will also be inc

subsequent es

the extent prac

193 Reviewer 5 13 Ch. 14 49

Adaptation of SPARROW analysis to the

sub‐estuary scale is warranted

There are limit

applicability of 

for EPA’s propo

clarification on 

SPARROW mod

comment will a

into subsequen

effort to the ex
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194 Reviewer 5 13 Ch. 14 49

There is minimal discussion of

implementation of Vollenweider model

presented

See responses 

section has be

TSD for EPA’s p

195 Reviewer 5 13 Ch. 14 49

Some aspects of watershed

management are not adequately

addressed. The total loading rate can be

calculated, but the lake would be

receiving loading from multiple sources,

both point and non‐point. Any action

taken would be dependent on the

source(s) of the nutrient and a balancing

of the source reductions necessary to

achieve compliance. How that would be

apportioned or even determined among

the sources is left for later exposition.

No technical re

196 Reviewer 5 13 Ch. 14 50

Simple models will work well as a

primary screening tool as applied to

individual lakes with well‐constrained

datasets and boundary conditions butthere is a large uncertainty associated

with demanding too much predictive

capability from them, especially when

used to “batch process” the information

for groups of lakes

Nutrient criteron a regional b

requirements p

criteria develolimitations app

criteria derivat
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197 Reviewer 1 Additional Comments 51

Giving reviewers much more time and

even chances to question the original

authors would lead to a much stronger

final document

No technical re

198 Reviewer 5 Additional Comments 51

Overall, the document is a mixed result

due to several methodologies in theprocess of being developed; lack of

statewide applicability and the most

effective current methodology forstreams the SCI as a good functional

baseline from which to start

No technical re

199 Reviewer 5 Additional Comments 51

Dose‐Response analyses proved

unsatisfactory yet should, withadditional research and information

development, hold promise

No technical re

200 Reviewer 5 Additional Comments 51

Methods to determine whether the

upstream criteria are protective of

downstream waters are insufficiently

evaluated in this document

The downstrea

has been impr

expanded for t

proposed rule.
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201 Reviewer 5 Additional Comments 52

The SPARROW model should be applied

cautiously and only to appropriate

systems in assessing downstream

effects, namely those with well‐defined

channel flows, and well‐ especially toreceiving reaches and coastal waters

This comment 

subsequent an

TSD for EPA’s p

clarification on 

SPARROW mod

also be incorpo

application of S

estuarine crite

practicable.

202 Reviewer 5 Additional Comments 52

Document mostly lacks is an overall

orientation and strategy, a set of clear

recommendations, and an

implementation plan for bringing thesevarious approaches to bear

The orientatio

clarified in the 

rule.

203 Reviewer 5 Additional Comments 52

Determination of the boundaries of

analysis, of what protocol takes

precedence, when each would beapplied, where each is applicable, how

data and results are to be synthesized to

arrive at criteria is wanting

Comments are 

for EPA’s propo