----- Forwarded by Melanie King/RTP/USEPA/US on 04/16/2010 02:49 PM

----- |------------> | From: | |------------> >--------------------------------------------------------------------------- -----------------------------------------------------------------| |Umesh Dholakia/R2/USEPA/US |>--------------------------------------------------------------------------- -----------------------------------------------------------------| |------------> | To: | |------------> >--------------------------------------------------------------------------- -----------------------------------------------------------------| |Melanie King/RTP/USEPA/US@EPA |>--------------------------------------------------------------------------- -----------------------------------------------------------------| |------------> | Date: | |------------> >--------------------------------------------------------------------------- -----------------------------------------------------------------| |04/16/2010 02:27 PM |>--------------------------------------------------------------------------- -----------------------------------------------------------------| |------------> | Subject: | |------------> >--------------------------------------------------------------------------- -----------------------------------------------------------------| |Re: rich burn engines |>--------------------------------------------------------------------------- -----------------------------------------------------------------|

NY has NOx RACT rules for existing major sources and the engines can meet the NOx limit by low emission combustion techniques- small engines do not have any NOx controls as I informed you earlier. FYI.

From:•Melanie King/RTP/USEPA/US To:•Umesh Dholakia/R2/USEPA/US@EPA Date:•04/16/2010 12:26 PM Subject:•Re: rich burn engines

Great, thanks so much for your help, I really appreciate it. 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: | |------------> >--------------------------------------------------------------------------- -----------------------------------------------------------------| |Umesh Dholakia/R2/USEPA/US |>--------------------------------------------------------------------------- -----------------------------------------------------------------| |------------>| To: |

|------------> >--------------------------------------------------------------------------- -----------------------------------------------------------------| |Melanie King/RTP/USEPA/US@EPA |>--------------------------------------------------------------------------- -----------------------------------------------------------------| |------------> | Date: | |------------> >--------------------------------------------------------------------------- -----------------------------------------------------------------| |04/16/2010 11:46 AM |>--------------------------------------------------------------------------- -----------------------------------------------------------------| |------------> | Subject: | |------------> >--------------------------------------------------------------------------- -----------------------------------------------------------------| |Re: rich burn engines |>--------------------------------------------------------------------------- -----------------------------------------------------------------|

There are many more without controls...%? I guess 2-5% may have controls.

From:•Melanie King/RTP/USEPA/US To:•Umesh Dholakia/R2/USEPA/US@EPA Date:•04/16/2010 09:23 AM Subject:•Re: rich burn engines

Thanks Umesh! On the NJ engines, do you know how many total engines there are (including uncontrolled ones) - so that we can say X percent have controls? 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: | |------------> >--------------------------------------------------------------------------- -----------------------------------------------------------------| |Umesh Dholakia/R2/USEPA/US |>--------------------------------------------------------------------------- -----------------------------------------------------------------| |------------> | To: | |------------> >--------------------------------------------------------------------------- -----------------------------------------------------------------| |Melanie King/RTP/USEPA/US@EPA |>--------------------------------------------------------------------------- -----------------------------------------------------------------| |------------> | Date: | |------------> >--------------------------------------------------------------------------- -----------------------------------------------------------------||04/16/2010 09:17 AM

|>--------------------------------------------------------------------------- -----------------------------------------------------------------| |------------> | Subject: | |------------> >--------------------------------------------------------------------------- -----------------------------------------------------------------| |Re: rich burn engines |>--------------------------------------------------------------------------- -----------------------------------------------------------------|

Hi! Melanie: PR and VI do not have any control requirements for rich burn spark ignition gas fired engines- there are no gas fired engines.In NJ-- Here are the findings -based on a 2008 list2 Rich Burn NG engines with < 500 BHP controlled by NSCR ( non selective catatlytic reduction) 1 Rich Burn NG engine at 500 BHP controlled by NSCR 6 Lean Burn NG engines at < 500 BHP controlled by Catalytic Oxidizer There is a larger number of NG engines > 500 BHP with add on control. In NY- to the best of my knowledge- there is no control requirement for spark ignition engines. For a gas fired engine- generally NY would require a SCR control anyway. If I find anything more I will let you know. Umesh

From:•Melanie King/RTP/USEPA/US To:•Umesh Dholakia/R2/USEPA/US@EPA Date:•04/15/2010 09:45 AM Subject:•rich burn engines

Hi Umesh, I'm hoping you can help me with a question. We're trying to get ahandle on what the current landscape is for rich burn spark ignition (gasfired) engines in terms of how many of the existing engines that are already in use have emission controls (non-selective catalytic reduction or NSCR) installed. The reason I'm asking this is that we are looking at what the impacts of the upcoming final NESHAP for existing spark ignition engines would be if controls were required for those engines, and it would be helpful if we had some idea of how many of them already have these controls even in the absence of the NESHAP. The engines we'd be concerned with are those that are <500 HP at major sources of HAP and any HP at area sources of HAP, since we already have limits on the ones that are >500 HP at major sources. Do you know of any estimates of how many of these engines are controlled for the states in Region 2? 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