**NCEE Comments on Ozone NAAQS RIA (Version submitted to OMB
2/29/08-3/5/08)**

**Executive Summary**

p\. ES-2, last paragraph: Table ES.5 is different than ES1 through 4.
This table should be described and discussed separately. Will clarify

p\. ES-3, why not add the visibility benefits to tables ES1-ES4? If it
there is no time, then please add table footnote: "These tables do not
include visibility benefits, which are estimated at \$160 million/yr."
clarified in text

p\. ES-4, A general comment on table footnote \*\*\*\*: We find this
description and column and row label in the table confusing because PM
co-benefits are included here too. We've heard several folks ask for
clarification on this in interagency calls, etc., and we think it could
easily be rephrased to make it clearer. Please change column heading
from "Mortality Function or Assumption" to "Ozone Mortality Function or
Assumption" and change the row label from "Assumption that association
is not causal" to "Assumption that ozone mortality association is not
causal" in Tables ES1-ES4. These table labels were negotiated during the
proposal with OMB. While I concur they could be clarified, I don't plan
to reopen this discussion with OMB because it could raise other issues
in formatting.

p\. ES-4, footnote \*\*\*. Do you think OMB is going to be okay with
only presenting costs at 7% given past discussions? Will wait for their
comments. As stated previously, we don't have the data to present 3%
figures

p\. ES-5, the sentence that starts "The bulk of the data..." is
incorrect and should be deleted. The data shows that there are
approximately an equal number of combinations of B and C assumptions
yielding positive net benefits as there are assumption combinations
yielding negative net benefits, NOT that the benefits are commensurate
with the costs. A visual review of the second figure shows that there
are more "green bars" or positive net benefits than "blue bars" or
negative net benefits. What lead you to the conclusion of equal number?

p\. ES-5, Table ES-5: \* and \*\* do not appear in the table. Please add
them to the table. Ok

Labeling edits similar to those suggested above: no for the reasons
above

\- change "Standard Alternative and Model or Assumption" to "Ozone
Mortality Model or Assumption",

\- change "Assumption that association is not causal" to "Assumption
that ozone mortality association is not causal", and

\- change "Combined Range of Ozone Benefits and PM2.5 Co-Benefits" to
"Combined Ozone Benefits and Range of PM2.5 Co-Benefits".

p\. ES-6-7: Figures need to be numbered. ok Also, please provide the
same figures at 3%. We deliberately only provided the 7% figure. The
addition of a 3% figure (with the attendant difficulties with the 3%
costs) would not change the conclusions which can be drawn.

Pg. ES-8, fourth bullet: It is not clear how the range of PM 2.5
benefits are conveyed in figure ES-1. Need clarification on this point.
Figure 1 contains the full range of the 12 experts plus Pope and Laden
studies.

p\. ES-8, last bullet: Maybe the phrase on UV effects can be deleted
since it is provided in an appendix. Or refer reader to appendix for
preliminary estimate of this disbenefit? We need to discuss the
characterization of the UVb and CEA appendices. I have a call into
Nathalie on this.

**Chapter 1**

No comments.

**Chapter 2**

No comments.

**Appendix Chapter 2**

The discussion in the appendix focuses on the small changes in emissions
yet the number of areas that are now in attainment that were not in
attainment in the proposal are significant. What is driving this change
then? Will try to clarify

**Chapter 3: M**odeled Control Strategy: Design and Analytical Results

p\. 3-1, second paragraph, 3^rd^ sentence: where are the state and
federal programs listed? Missing cross reference

p\. 3-9, Figure 3-4, footnote a: You should also find a way to mention
"additional national mobile tech" and the international aircraft NOx
std. And what about RFS? Was it included in the Base Case? We are
assuming it is, given that the proposal indicated that for the final,
"The starting point for the analysis will include only and all
promulgated

rules, including the Renewable Fuel Standard rule.\"

The link or table listing all promulgated state and federal regulations
in base case is missing from p. 3-1 so we are unsure what is in the base
case. Also these regulations should be mentioned here. RFS is part of
the base case.

Also, what about the impact of PAN? Again, the proposal indicated that
for the final, \"EPA will examine whether this increase in PAN will
affect baseline ozone concentrations in some areas and how this effect
can be quantified and incorporated into the baseline.\" I believe that
Al agreed with Tyler Fox that this would be dealt with more
appropriately in the OTAQ GHG rule. I recognize that the GHG rule has
not moved forward but it still seems like this RIA is not the
appropriate forum for this issue.

p\. 3-18, Figure 3-8: why do you add "...in Addition to National Mobile
Controls.." to the title of the figure when these controls are part of
the Baseline? Will clarify

p\. 3-25, Table 3.3 and Figure 3.14: tons reduced by E, W, and CA should
be included here too. We understood our prior discussion to be limited
to presenting just the costs and benefits for the regional breakout. I
consider presenting the regional breakout of tons would be a nice to
have at this stage as opposed to required. We can discuss if there is
something I am missing.

**Chapter 3 Appendix**

(See some comments in Ch. 5 below on new supplemental controls)

**Chapter 4: Approach for Estimating Reductions for Full Attainment
Scenario**

p\. 4-3, Figure 4.1: Replace "Sensitivity Analyses" in graph title and
legend. OK

p\. 4-7, Table 4.1: We still find the estimates for San Joaquin and
Houston strange. How is it that S.J. has such a higher 2020 design
value, yet the two areas need approx. the same % reduction in emissions
to get to 0.084 and Houston needs significantly higher % reductions to
get to all the alternative stds? Can you provide and intuition for why
this should be the case? (Also begs the question of why S.J. is assumed
to get extreme status and Houston isn't even applying for
reclassification?) Will check and try to clarify in text

p\. 4-8, footnote 6: Why is 0.0717 truncated to 0.071? Esp. since on p.
4-4, footnote 5, you explicitly keep 4 significant digits on the design
value to improve precision. Please provide an explanation for why you
truncate the design values. We will work with the AQ modelers to clarify

p\. 4-9, end of 1^st^ full paragraph: We still do not agree with your
truncation conventions. The design value has to get to 70.4, not 70.9,
to attain the std. Please provide a justification for the truncation of
70.9 ppb to 0.070 ppm. We will work with the AQ modelers to clarify

P 4-14 and 4-15, Figures 4.3a-d: Please rephrase "Extrapolated Cost
Counties". We are not talking about costs yet so this is a strange
heading. We will work with the AQ modelers to clarify

p\. 4-18, bullet (a): But why were any controls applied in the modeled
control strategy if it was already at 0.070 in the baseline? I would
assume based on the baseline modeling, Cincinnati would simply have zero
costs and benefits of attaining 0.070, 0.075, and 0.079. What is there
to remove?? We will work with the AQ modelers to clarify

p\. 4-19, Table 4.8: For those areas with 2020 Baseline values \> 0.070
and 2020 control case values \< 0.070 it makes a little more sense, but,
again, I do not understand why we should see any "ALL"s in the 0.070
column. We will work with the AQ modelers to clarify

p\. 4-19, last paragraph, 2^nd^ sentence: Change "...are equal to the
baseline minus control case reductions..." to "are equal to the baseline
minus control case emissions". We will work with the AQ modelers to
clarify

**Chapter 5: Engineering Cost Estimates**

p\. 5-1: Move footnote 1 into the main text. ok

p\. 5-3, last paragraph: how/why did you use the benefit per ton of
reductions in VOC's to select the cap? Reword to clarify

p\. 5-4, Figures 5.1 and 5.2: do these curves include the marginal costs
of the supplemental controls that were added? If not, why not? These
curves reflect the modeled control strategy, and not supplemental
controls which were not part of the modeled control strategy

p\. 5-4, Figure 5.2: It is not clear from the cost curve, why a
\$5000/ton cost cap was chosen for VOC controls. Please explain why a
\$15,000/ton cost cap wouldn't have been more appropriate. Will clarify

p\. 5-7, Figure 5.3: Please provide comparable regional graph using 3%
discount too.

Add figure footnote: "Only includes areas required to meet the current
standard by 2020, does not include San Joaquin and South Coast areas in
California." As previously explained, we can not provide a 3% estimate,
3% is only available for nonEGU sources, so an additional chart would be
so similar as to be virtually meaningless

p\. 5-8, Table 5.1: I'm confused, why isn't the total cost at 3% and 7%
the sum (or at least close to the sum) of the East, West and CA? Do you
discuss the East, West, and CA break down in another chapter? Only
nonEGU controls were costed out at 3%, the differences in the totals
reflect that.

p\. 5-8, Table 5-1: Add footnote: "Only includes areas required to meet
the current standard by 2020, does not include San Joaquin and South
Coast areas in California." ok

p\. 5-10, last paragraph: It seems like unnecessary speculation to say
"areas that face difficulty attaining could qualify under the Clean Air
Act for an attainment date as late as 2030 (assuming designations in
2010)." We suggest deleting the unnecessary phrase. We disagree. This is
a statement of what is available under the law. This is one way that
States could choose to respond to a tighter standard.

p\. 5-11, excerpt from SAB letter: This is an awkward quote to take from
the SAB since you don't provide the reader with any explanation of what
the other two "approaches outlined" involved. Please explain other
approaches considered or remove quote. We will put the more complete
language from the proposal RIA back in.

p\. 5-12, Section 5.2.1.2.: This section needs to be rewritten along the
lines of what we suggested in 3/4/08 email discussions: pending separate
discussion with OPEI,

-   Please remove all discussion of AC from the discussion of the hybrid
    approach. It is unnecessary. If we start with the MC expression we
    can arrive at the proper form of the TC curve without the definition
    of AC. (See below for the derivation included in the 3/3/08 email
    exchange).

-   **Comments on N:**

    -   We have long thought that N should vary by region and be set
        equal to the cost of the last control applied in that region.
        This approach makes the most sense to us and we do not believe
        we\'ve heard a compelling argument against it.

    -   Should a constant N continue to be applied for all regions,
        however, we believe the known control cutoff of \$23,000 is a
        more defensible value than \$15,000. A nationwide 35% reduction
        in costs based on tech change (on top of the tech change
        adjustment provided by M) by 2020 seems unreasonable. We believe
        your assumptions about tech change are overly optimistic and
        that tech change should be accounted for by M only (not by N).

    -   If, however, you move forward with using the \$15,000 per ton
        estimate, we believe you should, at a minimum, provide examples
        of control costs that have declined by comparable amounts over
        an \~12yr period to ground-truth this assumption. In addition,
        we believe using M= 0.47 as your primary value and M=1 at the
        upper end would be more appropriate.

-   **Comments on M:**

    -   M needs to be defined/characterized more clearly. In our view, M
        alone is the variable that captures technological change and
        learning by doing (lbd). These should not be captured by N (see
        above).

    -   That said, we remain uncomfortable with your derivation of M in
        part because of its dependence on values of N with which we
        disagree (see above), but also because of the way the primary
        estimate of M is derived. Calculating a \"high value\" and then
        dividing by 2 to arrive at a primary estimate seems somewhat
        arbitrary in our reading. Can you provide further justification
        for this?

[\[ *Our derivation of marginal cost and total cost of unknown controls
(from 3/3/08 email exchange): *]{.underline}

> Marginal cost of attaining standard Y in area Z:
>
> Over the unknown portion,
>
> MC = N + cx
>
> So the total cost of unknown controls is
>
> =$\int_{0}^{E_{1}}{(\text{N } + \text{cx})\text{dx}}$
>
> = NE~1~ + (1/2)cE~1~^2^
>
> In your analysis, you have set c = 2NM/E~0~.
>
> Plugging this into the equation above yields:
>
> Total cost of unknown controls = NE~1~ + (1/2)( 2NM/E~0~ )E~1~^2^
>
> = (1 + MR)NE~1~
>
> In our view, the choice of functional form for c seems a bit arbitrary
> especially since the influence of R on unknown MC is questionable.
> That said, you could argue that the slope of the marginal cost curve
> should (a) decrease with technological change (and learning by doing),
> and (b) should be lower for areas that were able to achieve more
> emission reductions with known controls (i.e., the higher is E~0~). If
> you present M as an adjustment factor applied to N to account for
> technological change and learning by doing, then you can argue that
> the proposed functional form of c accounts for both things that could
> affect the slope of the marginal cost curve. This leaves open the
> question of what the appropriate estimates of N and M should be, but
> we believe it to be a more straightforward explanation of your
> approach. \]

p\. 5-13, Use different term than "jumping off". This will perhaps be
easier once the whole approach is explained more simply in the previous
section.

p\. 5-13, 2^nd^ to last paragraph: you state you "calculated the
marginal costs for the last control applied in all geographic areas for
nonEGU and Area known controls.." Why were supplemental controls
excluded? Also, please explain at least in a footnote why it was not
possible to include costs of controls applied in other source categories
in this calculation.

p\. 5-13, 2^nd^ to last paragraph:

"For simplicity and comparability we used the \$15,000/ton" is not a
sufficient justification for using \$15,000. And in the next sentence
you say "The jumping off price (N) should be interpreted as the cost of
the very first ton needed from the unknown control." -- Since \$23,000
was the cost cut off value used for applying known controls, this is why
we believe it to be a much more defensible value to use for the cost of
the very first ton needed from the unknown control.

p\. 5-14, footnote 8: The argument for why it was inappropriate to use
the R for Houston in calculating M is not clear. Please provide a
justification for this decision.

p\. 5-15, We understand the derivation of M but don\'t feel comfortable
with it because a) it is dependant on N which we disagree with, and b)
because of the arbitrary decision to reduce the initial estimate of M
(0.47) by half to use as your primary estimate of M, and then only
present 0.12 and 0.47 in sensitivity analyses. Upon what basis can you
claim that 0.24 is "the one expected to lead to the most dependable
estimate"? Also, the sensitivity analysis on M should not be relegated
to an appendix. Given the significant uncertainty around this entire
approach, these estimates should remain in the body of this chapter.

p\. 5-15, it is not clear from a theoretical perspective why "per unit
control costs would be expected to be higher if the unknown control
needed is twice the modeled control than if it is half the modeled
control."

p\. 5-15, discussion on Figure 5.5: Again, the whole reliance on and
presentation of AC is unnecessary and confusing. Why not just show the
total extrapolated cost by region, standard, and assumption on M?

p\. 5-17, Table 5.2: Why do some of the reductions needed in Table 5.2
not approximately equal (Table 4.7a -- Table 5a.12) -- most notably
Sacramento? Most of the supplemental controls listed in Table 3a.5 are
for VOC control, not NOX, yet the most of the significant changes in
emissions are for NOX. Why? What are these local controls? The section
referenced in Chapter 5 Appendix does not provide a complete discussion
or listing of the local controls used. Some of the changes are
substantial between Table 4.7a and Table 5.2 - for example, Atlanta, GA,
Sacramento Metro, CA, San Juan, NM and St. Louis, MO-IL to name a few.
Why? What local supplemental controls are leading to these big
reductions? Will review and clarify as needed

p\. 5-17, Table 5.2, footnote a: Where are the costs of the supplemental
measures included? For example, Ch. 4 showed Cincinnati needing 9400
tons beyond the control scenario to reach 0.065. so were supplemental
controls added to achieve this redn so no hybrid or fixed extrapolated
cost estimate is necessary for this area? If so, then is the cost of the
additional supplemental controls included in Table 5.1? or have I just
not gotten to it yet? In chapter 5 appendix, will clarify in text

p\. 5-18, last paragraph, reference to Appendix 5a.4.3: Please include
the \$10,000 and 20,000 based estimates in the body of the chapter. I
don't think it would add too much length and it would keep it consistent
with our proposed presentation of the hybrid sensitivity results. We are
willing to put the results of the sensitivity in body of the report.

p\. 5-19 -- p. 5-24, figures 5-6, 5-7, 5-8, 5-9, 5-10: Please add figure
footnote: "These estimates do not reflect benefits or costs for the San
Joaquin Valley or South Coast Air Basins. Please see Appendix 10b for
analysis of these areas." ok

p\. 5-20, 2^nd^ sentence: Again, I think the value of M is so uncertain
that it the sensitivity analysis deserves to stay in the body of the
chapter. Do not relegate to appendix. And again, I disagree with the
arbitrary decision to use 0.24 in the primary analysis.

p\. 5-21, 5^th^ sentence "It is more consistent to present the
extrapolated costs at the same discount rate as the modeled control
costs, for which a 7% rate was determined to be more representative of
actual costs (see section 5.1.3)." But that doesn't matter. Extrapolated
costs still need to be shown at 3% here -- even if you don't carry the
3% totals into the ES and summary chapter. As previously explained, 3%
numbers don't exist

P 5-21, Table 5-5: please delete "National Attainment in 2020" from the
table title. Given the table footnotes, it is unnecessary. disagree

p 5-21, Table 5-5: Why doesn't the \$3.3B for 0.070 match the total
known control costs in Table 5.1? Is it because of the additional
supplemental controls that were added in some areas not too far from
attainment (e.g., Cincinnati?). If so, then these supplemental control
costs need to be broken out in the table, or at least in a footnote to
the table and add discussion of them in the text around the table. It is
due to the supplemental and giveback controls. We will clarify &
footnote.

p\. 5-25, 2^nd^ paragraph, sentence starting with "Breakthrough...":
Please delete the end of this sentence: ", and thus deviate from the
assumption of one constantly increasing marginal cost curve". Just
because the slope may decrease and/or the curve shifts, it is still
upward sloping, i.e., you still have increasing marginal cost. Will try
to clarify

**Chapter 5 Appendix**

(See comments above regarding supplemental controls)

**Chapter 6: Economic Impact of Modeled Controls**

p\. 6-1, last sentence in b): Why couldn't you have added the other
supplemental control costs that were added in areas deemed not far from
attainment (e.g., Cincinnati). Wasn't the total control cost 3.3 bil for
0.070? Supplemental controls and givebacks was done as part of the
extrapolated costs, and the EMPAX modeling could not wait for that
portion of the analysis to be completed, we were running out of time.

**Chapter 6 Appendix**

No comments.

**Chapter 7: Incremental Benefits of Attaining Alternative Ozone
Standards Relative to the Current 8-hour Standard (0.08 ppm)**

p\. 19, UV section: [\[Still needs to be updated.\]]{.mark} need input
from OPEI

p\. 31, Figure 7.1: Please remove National from the figure title. Will
add footnote to clarify

Add footnote to Figures 7-1 -- 7-2: "This table reflects full attainment
in all locations of the U.S. except two areas of California. These two
areas, which have high levels of ozone, are not planning to meet the
current standard until after 2020. The estimates in the table do not
reflect benefits for the San Joaquin and South Coast Air Basins."

Presentational/formatting comments on tables beginning on p. 34:

-   Please delete the footnote about negative values in a confidence
    interval (e.g., footnote c in Tables 7-6, 7-10, 7-14, etc.). Readers
    who know what a confidence interval is understand what the negative
    values represent. If you insist on keeping the footnote, however,
    please at least delete the second part of the sentence "and should
    not be inferred to indicate that decreased ozone exposure may cause
    an increase in asthma-related emergency department visits", since
    this is not really correct and may be confusing. Need to discuss,
    not sure of point

-   Make sure the footnote regarding San Joaquin and South Coast is
    included in ALL tables: "This table reflects full attainment in all
    locations of the U.S. except two areas of California. These two
    areas, which have high levels of ozone, are not planning to meet the
    current standard until after 2020. The estimates in the table do not
    reflect benefits for the San Joaquin and South Coast Air Basins." In
    this version it is missing from several (e.g., Tables 7-7, 7-8,
    7-11, 7-12, 7-15, 7-16, etc.) ok

-   Include regional breakdown (East, West, CA) of both ozone and PM
    mortality and morbidity reductions and valuation for known vs.
    extrapolated benefits in the main body of the chapter, as is done in
    the cost chapter. We do not have that breakout since we only have AQ
    modeling for 070

-   How about combining some of the tables to reduce length (e.g., Table
    7-16 with the ozone morbidity table for 0.075 (table 7-14))? It
    would be pretty easy to do by just adjusting the title and adding a
    column. Would help to shorten the chapter and allow reader to easily
    see how much of each morbidity effect is due to PM vs. ozone. Could
    do the same with 0.079 (ie., combine tables 7-18 and 7-20). Might be
    harder with 0.070 and 0.065 since you have to deal with partial
    attainment for the ozone part. Not insignificant amount of work,
    does not fully solve issue, especially is problematic for some
    options as you point out

-   Also, if you use portrait instead of landscape orientation you could
    combine ozone and PM mortality estimates by std; or combine ozone
    mortality and morbidity by std, and combine PM mortality and
    morbidity by std. See sample combination of tables 7-35 and 7-36
    pasted at the end of these comments. May be helpful but not an
    insignificant amount of work

p\. 7-74 -- 7-81, Table 7-42: Add 'ozone mortality' to column heading to
read "Ozone Mortality Model or Assumption". Add 'PM' to row labels to
read "PM2.5 Mortality Impact Functions Derived from Epidemiology
Literature" and "PM2.5 Mortality Impact Functions Derived from Expert
Elicitation". See comment on Executive Summary changes, not going to
reopen discussions on characterization.

Add table footnote: "This table reflects full attainment in all
locations of the U.S. except two areas of California. These two areas,
which have high levels of ozone, are not planning to meet the current
standard until after 2020. The estimates in the table do not reflect
benefits for the San Joaquin and South Coast Air Basins." ok

Figure 7.4 and 7.4: If you want to reduce length, then I suggest moving
these example tables to the appendix. We are including the figures to
help readers better understand results, based on internal management
briefings, they do help

Figure 7.5 and 7.6: Add table footnote: "This table reflects full
attainment in all locations of the U.S. except two areas of California.
These two areas, which have high levels of ozone, are not planning to
meet the current standard until after 2020. The estimates in the table
do not reflect benefits for the San Joaquin and South Coast Air Basins."
ok

p\. 7-85, #1: The placement of the CA discussion is a bit confusing. Are
you talking about areas in CA outside of SJ and SC, or all of CA? I
didn't think the SJ and SC estimates were included in any of the above
tables? If the SJ and SC estimate are not included in any of the above
tables then this placement of this discussion seems a little awkward.
Can you refer the reader to the appendix that discusses the SJ and SC
results? will clarify in text

Table 7.43:

-   This table is pretty good as a summary table, but it should also be
    broken down by region (E, W, and CA), along lines of Table 7-44.
    Interested readers can find the info in Table 7-44, we are focused
    on national estimates

-   Edit row label heading to read: "Ozone Mortality Model or
    Assumption"

-   Rephrase column heading to read "Combined Ozone Benefits and Range
    of PM2.5 Co-benefits by Standard Alternative" see previous comment
    about not changing

-   Probably need table footnote explaining what the range of PM
    mortality co-benefits encompasses. ok

-   Rephrase second column heading to read "Combined Ozone Benefits and
    PM2.5 Co-benefits by Standard Alternative" not modifying since
    consistent with proposal

Figure 7.7: I'm not sure this figure is necessary. It might be confusing
to some readers and lead one to think you are adding the expert K and E
PM mortality redns together. If you want to keep it, I suggest moving to
an appendix . We are including the figures to help readers better
understand results, based on internal management briefings, they do help

Table 7-47: Again, the non causal label is confusing. How about "Ozone
Morbidity (mortality non-causal)"? Or just "Ozone Morbidity" and include
table footnote on non-causal mortality assumption. Not changing

**Chapter 7 Appendix A**

p\. 3, second sentence (#4.): Is this also where you scale down any
benefits from "overcontrol" that occurred in the modeled control
scenario, as you did on the cost side? Will clarify

p\. 3, Section 7a-2: why are the partial attainment PM benefits only in
the appendix? Why not just add them as column in tables in main chapter
7 as was done for ozone benefits. consistent with proposal, do not add
value in chapter because not rolled back to current standard

**Chapter 7 Appendix B [\[Cost Effectiveness Analysis? Still needs to be
added\]]{.mark}** **need input from OPEI**

**Chapter 7 Appendix C**

p\. 7c-3, 3^rd^ paragraph: replace \$6.2 with \$6.6. I assume it was
just a typo? Will clarify

p\. 7c-4, Table 7c-1, and Tables 7c-4, 7c-5, 7c-6 on p. 7c-7: Add table
footnote: "Estimates do not include South Coast and San Joaquin Air
Basins". fixed Also mark footnote c on table 7c-6, and indicate that
visibility benefits are excluded in totals. fixed

**Chapter 8**

No comments.

**Chapter 9: Conclusions and Implications of the Illustrative
Benefit-Cost Analysis**

p\. 9-2, Tables 9.1a-d: Please add 'Ozone' to the column heading to read
"Ozone Mortality Function or Assumption". Also add 'ozone mortality' to
the last row label to read "Assumption that ozone mortality association
is not causal". In footnote \* add "which are estimated at \$160
million/yr" after visibility benefits. Not changing as previously
indicated

p\. 9-3, table footnote \*\*\*\*: I still think this footnote is
confusing, because PM mortality co-benefits are included here, right?
Please rephrase to read "Total includes ozone morbidity benefits and
PM2.5 mortality and morbidity co-benefits only." ditto

p\. 9-3, We don't see why Fig 9.3 is necessary. We would omit this (or
put it in an appendix), and instead, label a few of the combinations of
assumptions on the x-axis in We are including the figures to help
readers better understand results, based on internal management
briefings, they do help

Fig 9.2. You could then delete the last paragraph on p. 9-3 and the
bullets on page 9-4.

p\. 9-5 and 9-6, Figures 9.1 and 9.2: Please add the footnote "These
estimates do not include visibility benefits, which are estimated at
\$160 million/yr. Only includes areas required to meet the current
standard by 2020, does not include San Joaquin and South Coast areas in
California."ok

p\. 9-8, Table 9.2: Please add Ozone Mortality to the column heading to
read "Ozone Mortality Model or Assumption". Please change column heading
to "Combined Ozone Benefits and Range of PM~2.5~ Co-Benefits\*\*". And
change no causality row label to read "Assumption that ozone mortality
association is not causal" [.]{.underline} [not changing]{.underline}

p\. 9-12, number 1: It is not clear how you get an average at
\~\$6000/ton when you used a cut off value of \$5000/ton for known VOC
controls? Darryl help

p\. 9-12: It also seems some discussion of the special difficulty of
reaching attainment in all areas of CA (and hence including these areas
in the primary BCA) belongs in this chapter. Darryl help

p\. 9-13 number 4: What about the impact of PAN? (see comment above)
probably gone per earlier comment

p\. 9-14, number 7: Is the \$3.6 billion per year for CAIR in 2006\$?
Also, why not give total known+supplemental engineering cost estimate
and/or total including extrapolated costs? Darryl help

p\. 9-15, number 8, change "cost effective" to "known" control. You
should also add a footnote that states that the highest extrapolated
marginal cost was higher than the known control. Darryl help

**Chapter 9 Appendix A** **willing to work on jointly with OTAQ**

p\. 9a-1, 3^rd^ paragraph: Edit 2^nd^ sentence to read: "EPA begins with
a Base Case (that includes promulgated rules, consent decrees, existing
promulgated programs) and layers onto that illustrative control
strategies from...". At least this is our understanding of the steps.

p\. 9a-2, first paragraph: I think this needs some rephrasing. You are
not really replacing these mobile controls with anything else in order
to attain the current standard, so saying that the "cost for all
standards would increase..." isn't really correct, since this is no
longer incremental to full attainment of the current standard. .....

p\. 9a-3: Why is this section bulleted? Please put into paragraph form
to improve readability.

p\. 9a-5, Zero cost assumption on PHEVs seems incorrect because you are
not accounting for what consumers are giving up. It is inappropriate to
net out fuel savings unless there is a mechanism to force the adoption
of these controls, and if the cost imposed by their adoption is also
accounted for (costs in addition to the costs of technology that are
passed through). There is an opportunity cost to consumers associated
with the cost of additional fuel economy -- what they could have
purchased instead (e.g foregone further improvements in other vehicle
attributes, performance, etc.). That cost is not accounted for here.
Claiming that this is a no cost strategy seems to indicate that the
government can improve on private decision making and evaluating
trade-offs based on private costs and private benefits, which economists
would disagree with. Also, it is inappropriate to include taxes to the
technology costs faced by manufacturers or to include taxes when
calculating fuel savings. These are transfers that introduce the
possibility of double counting.

Need to summarize total tons reduced and total costs of each of the
three mobile controls (total tons reduced from PHEV and total tons and
costs of after market catalyst programs seems to be missing in this
version) at the beginning or end of the appendix.

**Chapter 9 Appendix B**

[\[Will send comments on draft received 3/5/08 shortly.\]]{.mark}

**Chapter 10**

No Comments.

Sample combination of tables in benefits chapter (combining Table 7-35
and 7-36):

  ----------------------------------------- -------------- ---------------
  **Illustrative 0.079 ppm Full Attainment                 
  Scenario: Estimated Annual Valuation of                  
  Reductions in the Incidence of PM                        
  Premature Mortality and Morbidity                        
  associated with PM co-benefit (Millions                  
  of 2006\$)^C^**                                          

  *Mortality Endpoint*                      *2020 Benefits *2020 Benefits
                                            (3% discount   (7% discount
                                            rate)*         rate)*

  **Mortality Impact Functions Derived from                
  Epidemiology Literature**                                

  ACS Study^A^                              \$1,800        \$1,600

  Harvard Six-City Study^B^                 \$4,100        \$3,700

  Woodruff et al 1997 (infant mortality)    \$5.0          \$4.0

  **Mortality Impact Functions Derived from                
  Expert Elicitation**                                     

  Expert A                                  \$8,400        \$7,600

  Expert B                                  \$6,400        \$5,700

  Expert C                                  \$6,400        \$5,700

  Expert D                                  \$4,400        \$4,000

  Expert E                                  \$11,000       \$9,500

  Expert F                                  \$5,800        \$5,200

  Expert G                                  \$3,700        \$3,400

  Expert H                                  \$4,700        \$4,300

  Expert I                                  \$6,300        \$5,700

  Expert J                                  \$5,100        \$4,600

  Expert K                                  \$1,000        \$910

  Expert L                                  \$4,400        \$3,900

  **Morbidity Endpoints^D^**                               

  Chronic Bronchitis (age \>25 and over)    \$120          

  Nonfatal myocardial infarction (age \>17) \$62           \$60

  Hospital admissions\--respiratory (all    \$1.4          
  ages)                                                    

  Hospital admissions\-- cardiovascular     \$3.8          
  (age \>17)                                               

  Emergency room visits for asthma (age     \$0.086        
  \<19)                                                    

  Acute bronchitis (age 8-12)               \$0.33         

  Lower respiratory symptoms (age 7-14)     \$0.083        

  Upper respiratory symptoms (asthmatic     \$0.10         
  children age 9-18)                                       

  Asthma exacerbation (asthmatic children   \$0.21         
  age 6-18)                                                

  Work loss days (age 18-65)                \$3.4          

  Minor restricted activity days (age       \$4.6          
  18-65)                                                   

  ^A^ The estimate is based on the                         
  concentration-response (C-R) function                    
  developed from the study of the American                 
  Cancer Society cohort reported in Pope et                
  al (2002), which has previously been                     
  reported as the primary estimate in                      
  recent RIAs.                                             

  ^B^ Based on Laden et al (2006) reporting                
  of the extended Six-cities study; to be                  
  reviewed by the EPA-SAB for advice on the                
  appropriate method for incorporating what                
  has previously been a sensitivity                        
  estimate.                                                

  ^C^ All estimates rounded to two                         
  significant figures. All estimates                       
  incremental to 2006 PM NAAQS RIA.                        
  Estimates do not include confidence                      
  intervals because they were derived                      
  through a scaling technique described                    
  above.                                                   

  ^D^ Morbidity Impact Functions Derived                   
  from Epidemiology Literature                             
  ----------------------------------------- -------------- ---------------