Document ID: EPA-HQ-OAR-2007-0225-0025
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2007-08-02T04:00Z

EPA Responses to Significant OMB Comments

Chapter Markups from 6/25/07

Executive Summary

1.  Page 1, footnonte- language on 0.079 ppm will be included in the
subsequent RIA

2.  Page 1, Overview, paragraph 1- changes accepted

3.  Page 1, Overview, paragraph 2- entire portion of California language
has been re-written for clarity.

4.  Page 1, overview, paragraph 3- accepted changes.

5.  Page 2, ES.1- Last two paragraphs accepted, with minor changes for
fluency.

6.  Page 3, footnote- RFS language is better suited in chapter 3. 

7.  Page 4-5, section ES.2- changes accepted to paragraph that splits
the pages.

8.  Pages 6-9, tables- changes made to table titles and footnotes.

9.  Page 10, ES.3- Caveats and Conclusions added per discussions on
conference calls.

Chapter 1

1.  Page 1- We have added language at end of first paragraph on
requirements of A-4.

2.  Page 6, Section 1.3.1- The RFS language is more appropriately placed
in chapter 3 with the detailed description of the baseline.

3.  Page 7, Section 1.4- All 0.079 language will be added to the
subsequent version of this RIA.

4.  Page 8, Section 1.4- The language on requesting comment in the NAAQS
proposal has been added.

5.  Page 8, Section 1.4- The sentence has been changed to reflect edit:

“…retaining the current standard is assumed to have no additional
incremental costs or benefits.”  

Chapter 4

1.  Page 1- 0.079 ppm will be addressed in a subsequent RIA

2.  Page 3, below Table 4.1- We did not calculate impact ratios for the
additional areas, as described in the text added in the paragraph
preceding Figure 4.2: 

	

	It is expected that these five zones would provide a representative
range of ratios, 	so the analysis was not done for Denver, Phoenix, and
Salt Lake City.  Because 	we were not calculating extrapolated tons for
Seattle, the ratio determination was 	not done for that region.  

3.  Page 4, Section 4.1.2- OMB commented “Add discussion about the
sensitivity of this radius to such things as lakes, borders, and other
states.”  A footnote was included to address this issue.

4.  Page 6, OMB commented “Discuss how sensitivity analysis of the
approach used will be conducted for the final.  Discuss how you will
incorporate regional impact ratios to better capture the heterogeneity
inherent in this metric. Also, qualitatively describe how different
assumptions about impact ratios will translate into higher/lower
extrapolated costs.”	This approach will be reconsidered for the final
RIA, and it is thus inappropriate to speculate on what will definitively
be done. A paragraph has been added that discusses the variables in
determining an impact ratio:

	The various methods did not generate consistent area-specific NOx
impact ratios.  	Actual area-specific impact ratios are likely
influenced by: importance of 	transport, local NOx/VOC ratios,
meteorology, and the location of monitors 	relative to source areas.
Higher impact ratios would yield lower estimates of 	needed extrapolated
tons and lower impact ratio estimated would yield higher 	extrapolated
tons/costs.  

Chapter 5

1.  Page 1—0.079 ppm will be addressed by the end of July.  This will
be integrated, and no need for a footnote.

2.  Page 4, Comment A1- This paragraph refers to the economic impacts of
modeled controls, not extrapolated costs.  This paragraph has been moved
to Section 5.1.3 with the limitations and uncertainties section.

3.  Page 5—The wording of the table and surrounding footnotes have
been incorporated into new text on discount rates.  This remains in
section 5.1.2

4.  Page 5—The list of uncertainties from the executive summary will
be included in the next version of this chapter.

5.  Page 6, Comment A2- Clearer language regarding California has been
added into this chapter. 

6.  Page 6, Comment A3- Sentences regarding the pros and cons of the two
different approaches have been put into this chapter.

7.  Page 7—Advances to medical technologies will be covered in the
benefits chapter, not this chapter.

8.  Pages 7-8—A revised paragraph, including language about Circular
A-4, has been added into this chapter. 

9.  Page 9, Comment A5- Language has been changed to address goodness of
fit and scope of the slope calculations.

10.  Page 12, Comment A6- This language, slightly modified, has been
added into the chapter. 

11.  Page 12, Comment A7- This language will be provided in the benefits
chapter. 

12.  Pages 13-15- Formatting of the table was changed, and the averaged
cost per ton was added per summary comments. The discount rate is
addressed in section 5.2.3, immediately preceding the tables.  

13.  Page 16—Language has been added to address both the discount rate
and the discussion of uncertainties.  

Chapter 8

1.  Page 1, Overview- all comments accepted. 

2.  Pages 1-2, Section 8.1, Presentation of results- Comments accepted,
with the exception of the unmarked deleted text on the description of
the tables.

3.  Page 1, footnote- all discussion of 0.079 will be included in the
subsequent version of this RIA.

4.  Page 2, and tables on pages 3-6- Tables edited per recommendations. 
Ozone and PM are not separated out, but are discussed on page 8 under
“relative contribution of PM benefits to total benefits.”  Text
added: 

	Because of the relatively strong relationship between PM2.5
concentrations and 	premature mortality, PM co-benefits resulting from
reductions in NOx emissions 	can make up a large fraction of total
monetized benefits, depending on the 	specific PM mortality impact
function used, and on the relative magnitude of 	ozone benefits, which
is dependent on the specific ozone mortality function 	assumed.  PM
co-benefits based on daily average concentrations are calculated 	over
the entire year, while ozone related benefits are calculated only during
the 	summer ozone season.  Because the control strategies evaluated in
this RIA are 	assumed to operate year round rather than only during the
ozone season, this 	means that PM benefits will accumulate during both
the ozone season and the rest 	of the year.   

	PM co-benefits account for between 13 and 99 percent of co-benefits,
depending 	on the 	standard analyzed and on the choice of ozone and PM
mortality functions 	used.  The estimate with the lowest fraction from
PM co-benefits occurs when 	ozone mortality is based on the Levy et al
(2005) study and when PM2.5 	mortality is based on the function provided
by “Expert K” from the expert 	elicitation.  The estimate with the
highest fraction from PM co-benefits occurs 	when no ozone mortality
reductions are included (following the assumption of no 	causal
relationship between ozone and mortality) and when PM2.5 	mortality is 
based on the function provided by “Expert E” from the expert
elicitation.

5.  Page 3- We did not include discussion of 2006$ due to internal
deliberations about feasibility.  7% was the only discount rate included
per the discussion in chapter 5.

6.  Page 4- Units were added to this table.

7.  Page 7, discussion of results- a section on “relative contribution
of PM benefits and total benefits” has been included, as described in
response 4 above. 

8.  Page 7, discussion of results- edits on “ and “challenges to
modeling full attainment in all areas” and Impacts of Uncertainty in
the Magnitude of Ozone Benefits” has been accepted and changed. 

	

9.  Page 8- comments mostly accepted.

10.  Page 9- OMB suggested adding the phrase “…and that there are
quantifiable benefits to reducing ambient ozone below each of the
alternative standards.) “  We did not take this comment since this
seems to imply that there is a threshold for effects.

11.  Page 9-  OMB suggested adding the sentence “However, we note that
there is additional uncertainty in the benefits extrapolations to the
extent to which unknown controls actually achieve the alternative
standards in some future year”  This paragraph was about the comparing
the modeled versus the extrapolated.  The first sentence is the only one
which relates to benefits, the remainder of the paragraph is about the
cost side so the deletion of the word cost and replacing it with
benefits was problematic in the second sentence.  The sentence you added
at the beginning did not seem to fit, as our sentence which follows
indicates, we expect that the relative uncertainties are similar.

12.  Page 9, section 8.3, comment A3- this list pertains to implications
of the results from the analysis, while section 8.2 is a simple
discussion of what the results show.

13.  Page 10, # 4- this is an additional part of the discussion on
technology and possible results from future innovation.

14.  Page 12, #6- OMB added the change” As such, we are likely
overestimating costs in the future, instead we provide sensitivity by
selecting a high and low fixed marginal cost curve.”  Assuming no
technological innovation over the next few decades is a very
conservative assumption which leads to an upward bias in the estimates. 

15.  Page 12, #7- Item #3 discusses that Non-EGU point sources
contributed heavily to overall emissions reductions.  Item #7 differs in
that it discusses costs, rather than emissions reductions, from Non-EGU
point sources. 

16.  Page 13, #10- OMB added the sentence “We acknowledge, however,
that the costs and benefits of this rule may fall disproportionately
across regions and may result in regionally significant adverse economic
impacts” It may be you are referring to California here and we have
less of an issue with this if more focused.  As a generic statement, we
would say that those that need to get additional reductions will pay the
cost but also get the benefits.  However, we can not say that this
change in the standard may result in regionally significant adverse
economic impacts as a general statement.  Even in the case of
California, it is not just this change in standard which leads to reduce
emissions, there are numerous other factors (e.g. climate change, energy
concerns etc) which play a complementary and probably more significant
role.