1

What is in the Portland Cement Reconsideration Package

Background

In May 2011 we published our list of reconsidered items from the 2010 promulgated rule, 

which we were petitioned on, both by industry and environmental groups. In December 

2011, we received a remand from the courts that required us to also reconsider the MACT 

floors since the Nonhazardous Secondary Materials (NHSM) rule had promulgated, and now 

CISWI kilns that were in our original floor, were no longer part of the PC package. In April 

2012, a consent agreement was reached with the PCA that requires us to consider proposing 

an extended compliance date and consider the impact of a petition from Holcim Cement 

regarding adequacy of the UPL equation. This package addresses these topics.

 New source standards are unchanged except for PM– the court opinion did not affect the 

floor calculation for new sources.

 Floors for PM, THC, mercury and HCl for existing sources were recalculated with all 

CISWI kilns removed.

 We are proposing to remove the requirement that the PM CEMS meet the requirements 

of PS-11. Instead kilns and clinker coolers must install a PM CEMS that will be used as a 

continuous parameter monitoring system (the same as was done in the MATS rule)

 Compliance dates

o Extended to September 9, 2015 for PM, THC, mercury, and HCl limits and 

associated monitoring

o Shortened to 6 months from promulgation for open clinker storage requirements 

and startup/shutdown recordkeeping requirements. 

 Kilns with HCl controls would have the option to use an SO2 monitor to demonstrate that 

the HCl control device is operating properly rather than monitoring control device 

parameters.

 Coal mills which are heated by cement kiln exhaust (which are currently unregulated by 

any rule) are regulated as follows:

o If the coal mill has a separate stack it is by the Coal Preparation NSPS. Mercury, 

THC, and HCl testing is required to demonstrate that the appropriate kiln 

emission limits are not circumvented.

o If the coal mill exhaust is recombined with the cement kiln exhaust, the coal mill 

is treated an integral part of the cement kiln.

 We corrected other testing and monitoring issues raised by industry.

 Changes to monitoring and emissions limits are shown in the attached table.
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Pollutant/Source Limit in 2010 rule Proposed Limit in 

Reconsideration

Comments

Mercury 55 lb/MM tons 

clinker

55 lb/MM tons clinker This is now a 

beyond-the-floor 

standard

THC 24 ppmvd 24 ppmvd We incorporated 

additional 

variability from the 

best performing 

source (on average) 

which raised the 

limit from 15 to 24. 

The best performing 

source is a CISWI

kiln

Alternative Organic 

HAP

9 ppmvd 12 ppmvd This limit was 

raised due to a 

recalculation of the 

lowest limit that can 

be reliably 

measured.

PM – Existing Sources 0.04 lb/ton clinker 

based on a 30 day

average

0.07 lb/ton clinker 

based on a 3 run stack 

test

Most of the increase 

is due to changing 

the PM CEMS 

requirement to a PM 

CPMS and a stack 

test

PM – New sources, 

NSPS and NESHAP

0.01 lb/ton clinker

based on a 30 day

average

0.02 lb/ton clinker

based on a 3 run stack 

test

Change is solely 

due to the changes 

in compliance 

averaging time

NSPS PM limit for 

Modified kilns

0.01 lb/ton clinker

based on a 30 day

average

0.07 lb/ton clinker

based on a 3 run stack 

test

HCl 3 ppmvd 3 ppmvd

Startup/shutdown Same as steady state 

operation except that

all lb/ton production 

limits are changed to 

an equivalent 

concentration limit

No change
3

Pollutant/Source Limit in 2010 rule Proposed Limit in 

Reconsideration

Comments

Monitoring during 

startup/shutdown

Required with a 7-day

averaging period

Monitoring not 

required. Facility

would be required to 

keep records of fuel 

and raw materials use 

and estimate emissions

HCl Monitoring by

CEM

Required for all kilns 

that do not have a wet 

scrubber

Only required for kiln 

that have no add-on 

HCl controls

Outdoor Clinker 

Storage piles

Partial or total 

enclosures based on 

requirements 

developed by 

SCAQMD

Work practice 

standards that codify

current industry

practice