From:     "Higgins, Cortney" <Cortney_Higgins@omb.eop.gov>                                                                                         

To:    Keith Barnett/RTP/USEPA/US@EPA                                                                                                           

Date:       08/06/2010 11:28 AM                                                                                                                      

Subject:   edits on insert language                                                                                                                 

Please let me know if you have questions.

Regards,

Cortney

(See attached file: edits_PC_insert.docx)
Although the Agency has concluded that it is reasonable to set the same mercury standard 

for all cement kilns, we acknowledge the unique challenges that the highest emitting 

sources may face in meeting the reductions within the regulatory compliance timeline. In 

particular, as discussed at length above, the two highest emitting kilns – the kilns located 

in Durkee and Tehachapi -- have unusually high levels of mercury in their proprietary 

limestone quarries, which, as typifies this sector, are located proximate to kiln operations. 

The mercury content of source material is the key factor in the high levels of emissions 

experienced at these kilns and a complicating consideration in their ability to achieve 

compliance in a timely manner. 

We also recognize that this challenge presents a unique opportunity to achieve substantial 

reductions in a persistent bioaccumulativethis naturally occurring, persistantpersistent, 

and neurotoxin widespread contaminant bioaccumulative neurotoxin in an amount and on 

a schedule that exceeds what will be required in the final rule. The Agency believes that 

the two sources in question may be able in the near term to install aggressive controls, 

including activated carbon injection, that would result in dramatic near term reductions in 

mercury emissions (as much as 90% or two tons of mercury emissions in the first two 

years of operation).). If they were to do so, these sources would emit substantially less 

mercury in the next few years than the alternative of allowing these facilities to continue 

to emit at current levels for three additional years, as would otherwise be the case. This 

would be a very substantial reduction in emissions of this pollutant. Annual emissions of 

mercury from all sources (not just cement kilns) are estimated to be 50 tpy,, so that a two 

Comment [A1]: Not all forms are 

bioaccumulative. In fact mercury is typically 

changing forms. It is persistent because it is a metal 

and metals are never destroyed that part is obvious 

and not really needed. These changes track with 

what is on the EPA mercury webpage -- 

http://www.epa.gov/mercury/about.htm

Comment [A2]: Can EPA share these 

calculations with us? 

Comment [A3]: Will EPA be making this cost 

prohibitive? Or does EPA expect them to do this 

without shutting down?

Comment [A4]: Please provide a source 

including a url ; Also, why not include information 

about the baseline emissions of cement kilns as 

well? 
ton reduction is a substantial reduction of total national emissions of this potent, 

bioaccumulative neurotoxinmercury.neurotoxin. 

We understand that one of the two high emitting kilns has already installed activated 

carbon injection, but that its performance could be further optimized.. See 74 FR 21148. 

The other kiln would have to install activated carbon injection and both kilns would need 

to install dust shuttling. The net benefit to the environment and public health would 

extend a number of years beyond the MACT compliance deadline. 

If the Durkee and Tehachapi kilns were willing to make a near term reduction (e.g., 90 

percent) in their mercury emissions significantly before the compliance date in the rule, 

the Agency would be willing to entertain providing these kilns a compliance schedule 

that extends beyond the three to four years specified in this rule. The purpose of such an 

approach would be to provide a substantial net benefit to the environment; therefore 

ultimate compliance with the MACT standard would need to be by a date that ensures the 

long term emissions from these sources would be significantly lower than their emissions 

from meeting the standard on the schedule in the rule. Given the bioaccumulative nature 

of mercury and the additional reductions that could be obtained, the Agency is interested 

in exploring this concept. 

Finally, EPA notes that the same early reduction opportunities for mercury do not appear 

to exist for the rest of the Portland cement industry. It typically takes on the order of 

three years to install activated carbon injection technology. One of the high mercury 

plants has recently completed installation of ACI and has just commenced full scale 

Comment [A5]: Please explain this – you mean 

that it’s not yet at 90%, right? 

Comment [A6]: Sounds like a very weak 

commitment. 
operation of the kiln with ACI installed. The other kiln faces less installation barriers 

than other kilns. This is because the company has tested carbon injection and dust 

shuttling on one of its other kilns, and is already using dust shuttling to reduce emissions 

at another kiln, and is therefore better positioned to rapidly install controls after one year. 

To our knowledge, these circumstances are not applicable to the rest of the Portland 

cement source category, and could not even be duplicated at all the other facilities owned 

by these companies due to limitations in infrastructure available to design and build these 

systems.