From: O’Hare, Andrew < AOhare@cement.org >

To: Sharon Nizich/RTP/USEPA/US@EPA

Date: 11/30/2011 03:26 PM

Subject: FW: Thursday Conf Call with EPA

Sharon,

Curtis Lesslie with Ash Grove has provided a response to your query from his
perspective which we may discuss on the call tomorrow.

Regards,
Andy

From: Curtis Lesslie [ mailto:curtis.lesslie@ashgrove.com ]

Sent: Wednesday, November 30, 2011 2:43 PM

To: O’Hare, A ndrew

Cc: Satish Sheth; Michael.Pelan@lafarge

- na.com ; Nugent, Daniel;
Hector.Ybanez@holcim.com ; Jason.Morin@ho lcim.com ; tmatz@htcnam.com
Subject: Re: Thursday Conf Call with EPA

Andy:
Not sure if anyone else has attempted to provide a response to EPA's questions,
but I put together the following, for what it's worth, if you want to consider
providing something to them prior to our call.

1. How variable is the exhaust flow and Hg content of the kiln exhaust ducted

from the kiln to the coal mill?

In

- line coal mills that rely solely on kiln gas for heat can only operate with the kiln is up, but do not operate at all time when the kiln is up (there is a
ground coal storage bin for periods when the coal mill is down). When the coal

mill is operating, the flow typically is about 7% to 10% of the kiln gas flow.

Ash Grove's in

- l ine coal mills run in the range of 15,000 to 20,000 cfm and flow
should be stable when operating normally.

The gas supplied to the coal mill comes off the preheater tower. I am not aware
of there being much mercury emissions data available from coal mill stacks. Data
from our Durkee plant indicates that emissions of mercury from the coal mill are in the range of 3 lb/MM ton clinker (vs.
2670 lb/MM ton clinker at the kiln stack (if uncontrolled)). Mercury is a

strange beast, but if the Durkee data is app lied across the industry, we would
expect very, very low mercury emissions from in

- line coal mill stacks.2. Is the kiln exhaust ducted to the coal mill before or after the kiln APC?

As noted above, kiln gas is routed to the coal mill from the preheate r tower, so
it is prior to the kiln APCD. We need gas temperatures in the 500 F range. Most

kiln APCD inlets now run at maximum temperatures less than 400 F for compliance
with D/F standards, so this gas would be too cool for use in an in

- line coal

mill.

3. Is it possible to reroute the coal mill exhaust back to the kiln APC? If
there are facilities that already do this, what is the benefit

- cost or

otherwise?

This will vary by plant, depending on the location of the coal mill in relation
to the kiln APCD. Of course, one cannot just add 15,000 to 20,000 cfm to any
existing baghouse without considering the existing flow of the baghouse and
potential impacts on production by adding this flow. As with any change in the
method of operation or physical change, changes in the kiln stack flow and
concentrations also could translate to permitting and/or modeling issues. If the
stacks are currently permitted separately, it would require some work to get them

combined.

I am n ot aware of any coal mill baghouse that subsequently vents to a kiln main
baghouse, though many do vent to common stack shared with the kiln baghouse.

Since indirect fired, in

- line coal mill baghouses operate more like separators (ground coal from drying air), the coal mill baghouse operates independently and

the kiln baghouse is unnecessary, furthermore, if you have a failure of the coal
mill baghouse, you don't want to send dried & ground coal into the main baghouse when the temperature exceeds 200 F (th ey typical maximum safe coal mill baghouse inlet temperature).

Curtis Lesslie, PE

Vice President Environmental Affairs

Ash Grove Cement Company
11011 Cody St., Overland Park, KS 66210

P: (913) 319

- 6065 M: (785) 550

- 6330

www.ASHGROVE.com

On Tue, Nov 29, 2011 at 12:04 PM, O’Hare, Andrew < AOhare@cement.org >

wrote:

> > Folks,

>

>

> > A friendly reminder regarding the conference call with EPA onThursday, December 1 at 11:3 0 a.m. EST (details below). Also, I received a few
questions from Sharon last week (pasted in below), which I explained we could

discuss on the call. Lastly, I have forwarded to her attention the summary

status of the various reconsideration issues from our perspective (attached).

>

>

> > Regards,

> > Andy

>

>

> > Sharon’s questions:

>

>

> > For our discussions next Thursday, I wanted to give you a list of
technical items we are trying to resolve relative to the coal mill that receives

kiln exhaust. If these are cut and dry, perhaps you can just send me a response

via email. Otherwise we can discuss Dec 1.

>

>

> > 1. How variable is the exhaust flow and Hg content of the kiln

exhaust ducted from the kiln to the coal mill?

>

>

>

> 2. Is the kiln exhaus t ducted to the coal mill before or after the

kiln APC?

>

>

>

>

> > 3. Is it possible to reroute the coal mill exhaust back to the kiln
APC? If there are facilities that already do this, what is the benefit

- cost or

otherwise?

>

>

>

>

>

>

>

> From: O’Hare, Andrew

> Sent: Thursday, November 17, 2011 3:05 PM

> To: O’Hare, Andrew; 'Satish Sheth'; 'Curtis Lesslie'; '
Michael.Pelan@lafarge

- na.com '; 'Nugent, Daniel'; '
Hector.Ybanez@holcim.com '; 'Jason.Morin@holcim.com'; 'tmatz@htcnam.com'
> Subject: RE: EPA Conference Call>

>

> > Folks,

>

>

> > Just heard back from EPA. Call is scheduled for Thursday, December 1 at 11:30 a.m. EST. Dial in number: (9 19) 541

- 4332. Additional details on
discussion topics to follow. Attached is a thumbnail of the status of the

reconsideration issues to date.

>

>

> > Regards,

> > Andy

>

>

> > From: O’Hare, Andrew

> Sent: Thursday, November 17, 2011 2:42 PM

> To: 'Satish Sheth'; 'Curtis Lesslie'; 'Michael.Pelan@lafarge

- na.com';
'Nugent, Daniel'; 'Hector.Ybanez@holcim.com'; 'Jason.Morin@holcim.com';

tmatz@htcnam.com
> Subject: EPA Conference Call

>

>

> > Folks,

>

>

>

> Sha ron Nizich would like to have a conference to review some of the
NESHAP reconsideration issues on Thursday, December 1 at either 11:00 a.m. or

3:30 p.m. EST. Please pencil in these times and I will be back in touch to

confirm with additional details.

>

>

> > Regards,

> > Andy

>

>

>

> Andrew T. O'Hare

> > Vice President, Regulatory Affairs

>

> Portland Cement Association

>> 500 New Jersey Avenue, 7th Floor

> > Washington, DC 20001

> > Office: (202) 408

- 9494

> > Fax: (202) 408

- 0877

> > Cell: (202) 270

- 0094

>

> e

- mail: aohare@cement.org