Document ID: EPA-HQ-OAR-2008-0708-0501
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2010-08-12T04:00Z

----- Forwarded by Melanie King/RTP/USEPA/US on 08/10/2010 02:31 PM
-----
|------------>
| From:      |
|------------>
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
  |Melanie King/RTP/USEPA/US                                                                                                                 
|
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
|------------>
| To:        |
|------------>
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
  |"Higgins, Cortney" <Cortney_Higgins@omb.eop.gov>                                                                                          
|
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
|------------>
| Cc:        |
|------------>
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
  |Fred Talcott/DC/USEPA/US@EPA                                                                                                              
|
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
|------------>
| Date:      |
|------------>
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
  |08/10/2010 01:28 PM                                                                                                                       
|
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
|------------>
| Subject:   |
|------------>
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
  |Re: some interagency edits so far                                                                                                         
|
  >---------------------------------------------------------------------------
---------------------------------------------------------------|

Hi Cortney,
On the comment on the text on p. 30, we will add "including data that was not 
used in the proposal" to the end of that quoted text.  On the comment on the 
text on p. 42, we do not think it should be changed.  The point we are trying 
to make is that the vast majority of area source engines are subject to 
management practices so the vast majority of the rural engines at area sources 
are subject to management practices.
Unless Kevin has some data to show that rural area source engines are all 
4SLB/4SRB >500 HP, I see no reason to change the language there.

Melanie King
Energy Strategies Group
Sector Policies and Programs Division
Office of Air Quality Planning and Standards U.S. Environmental Protection 
Agency

Mail Code D243-01
RTP, NC  27711

Phone:  (919) 541-2469
Fax:       (919) 541-5450
king.melanie@epa.gov

|------------>
| From:      |
|------------>
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
  |"Higgins, Cortney" <Cortney_Higgins@omb.eop.gov>                                                                                          
|
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
|------------>
| To:        |
|------------>
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
  |Melanie King/RTP/USEPA/US@EPA                                                                                                             
|
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
|------------>
| Date:      |
|------------>
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
  |08/10/2010 11:27 AM                                                                                                                       
|
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
|------------>
| Subject:   |
|------------>
  >---------------------------------------------------------------------------
---------------------------------------------------------------|
  |some interagency edits so far                                                                                                             
|
  >---------------------------------------------------------------------------
---------------------------------------------------------------|

p.30 – Cited text pasted in below.  No one has suggested that EPA not base the 
MACT floor on emission results – others would question EPA’s new choice of 
data to represent the top 12% 100-500 HP 4SLB engines.
The proposal was also based on emissions data, so that is not a valid 
distinction. Why does that test data now include controlled engines?
EPA should refer to the “inadvertent omission” discussion on page 46 – or 
explain it in another matter here.

“EPA is also not using the Population Database to determine a percentage of 
engines that have emission controls installed, as it did at proposal.
The Population Database has not been updated since 2000.  It contains 
information regarding whether or not an engine has emission controls, but does 
not generally contain other types of emission-related information, like 
engine-out emissions or operational controls, and it does not include any 
emissions concentration data, which is necessary to determine the MACT floor.  
EPA determined that it would be more appropriate and more defensible to base 
the MACT floor analysis directly on the emissions data that EPA has for 
stationary SI engines.”

-------------------------------------------------
p. 42 – Cited text pasted in below – EPA’s requirement of management practices 
on OTHER ENGINES in no way provides relief to owners with engines in RURAL 
AREA SOURCES.  This irrelevant discussion should be deleted in its entirety.  
(We also disagree with the contention that rural and urban retrofit/testing 
costs are equivalent under GACT – but choose not to argue with EPA over this 
point.)

“EPA has taken steps in the final rule that reduce the burden on owners and 
operators of engines regulated in this final rule.  EPA has established 
management practice standards for most of the engines located at area sources 
of HAP.  The only existing stationary SI RICE at area sources that are 
required to meet numeric emission limitations are 4SLB and 4SRB non-emergency 
stationary SI RICE that are greater than 500 HP and operate more than 24 hours 
per calendar year; these engines are estimated to be only 7 percent of the 
population of existing SI RICE at area sources.  EPA believes that requiring 
management practices instead of specific emission limitations and/or control 
efficiency requirements on the vast majority of existing stationary SI engines 
at area sources alleviates concerns regarding costly and burdensome 
requirements for rural sources.”