Exhibit CC 03-01-2016 Item #11 Lehigh Noise ComplaintsTo: City of Cupertino Board and Planning Department
From: Cathy Helgerson -CAP -Citizens Against Pollution
Subject: Lehigh Southwest Cement and the City Noise Ordinance
Cc 3 /1 /1 h
#=ll
The City of Cupertino has concerns about Lehigh Southwest Cement and Quarry what about concerns
with the terrible pollution coming from Lehigh flowing over to our homes and to our families that has
become a serious matter. In reviewing Cupertino's noise ordinance how about a pollution ordinance
against anyone or company that pollutes our City seems like a good idea can the City Council look into
this?
Levels of noise if lower than stated ordinance levels for Cupertino and Santa Clara County are still a
nuisance to the surrounding area because the plant is extremely close to the residences noise pollution
is a quality of life issue. A sound that is reoccurring at any level is a nuisance and people should not have
to live in an area with this problem. The Sound Compliance Report states that the sound emitted by
normal operations is mostly constant this would seem to be extremely annoying and disturbing.
Lehigh's noises are continuous ongoing day and night keeping people awake and creating stress and
health issues to the public this needs to stop and is a violation of City, County, State and Federal
Regulations who will enforce this violation of the City noise ordinance?
The mining at Lehigh also causes noise from the blasting and can be heard for may miles people
complain about the noise at Lehigh and nothing is done about it of course please do not leave out the
ongoing pollution at the Cement Plant and Quarry destroying the health of the community.
Santa Clara County noise ordinance 40 dBA nighttime and 50 dBA regulation levels limits do not take
into consideration that especially at night sound travels and that there is an eco-effect which amplifies
the noise coming from the plant. Lehigh does a great deal of it's processing of cement at night under
cover of darkness to hide its pollution.
The Lehigh Cement Plant is centered in a small valley surrounded by mountains and the East Material
Storage Area which causes the noise emitted to be magnified. The readings do not reflect the
amplification of irritating noise coming from the plant. Evening levels and morning levels exceed
ordinance levels see Appendix C & D Comparative Measurement Data from their own report with dBF
Associates Under recommendations a detailed analysis of the plants equipment and processes would be
required to provide site specific recommendations this should have been done and was not done.
I am against the study conducted by Lehigh and dbf Associates and see that a lack of a complete analysis
was never conducted so I would like to ask the City of Cupertino to conduct their own study of Lehigh
and the noise and also to ask that they conduct a pollution study on the Fence at Lehigh which will
expose the true levels of pollution at the Cement Plant.
Lauren Sapudar
From: Toni Oasay-Anderson
Sent:
To:
Monday, February 29, 2016 8:53 AM
City Clerk
Subject: FW: City Council Meeting of 3/1/2016, Noise Study of Lehigh Cement Operation
From: kite [mailto:kite@orimp.com]
Sent: Saturday, February 27, 2016 5:01 PM
To: Barry Chang
Subject: City Council Meeting of 3/1/2016, Noise Study of Lehigh Cement Operation
Dear Mayor Chang:
Re: Noise study of Lehigh Cemment Operation
Item #11, 3/1/2016 City Council meeting
We are sending this to you directly as no agenda has yet been posted
for the March 1 City Council meeting, nor did the news announcement
concerning this meeting or your 212612016 message indicate where
written communications regarding the noise study should be sent.
We reside at 22386 Cupertino Road, approximately 600' east of the
intersection of Cupertino Road and Foothill Blvd., and about 4500'
from the entrance of the Lehigh Southwest Cement facility (Permanente
Quarry). At this location we can hear the sound of trucks traveling
to and from the facility, and the engines/horn of trains making
deliveries. Operations at the facility itself are only audible on
quiet evenings, and then primarily when the facility's master caution
horn sounds.
On the whole, we have not been bothered by noise related to the
facility. (Indeed, the noise created by trucks making deliveries to
the Sunnyview retirement facility across the street from our house is
both more apparent and more bothersome.)
The sounds of trains making deliveries to Lehigh are quite audible
from our house and might be bothersome if such deliveries were
frequent. Fortunately, they have never been frequent and have become
less frequent in recent years.. (Full disclosure: We like trains so
are genera111y biased in their favor.)
While truck traffic to and from Lehigh is not loud enough to be
bothersome at our house, in recent months we have noticed some
increase in the use of compression braking Gack brakes), which makes
quite a racket. We do not know if these trucks are from the Stevens
Creek Quarry or the Lehigh facility; ifthe former, this issue would
not pertain to a Lehigh-specific noise study. (We do know that when
the Pern1anente Quarry was operated by Hansen they specifically
1
·M: l J
requested truckers to avoid using compression braking until on or
north of the I-280 on-ramps.)
We are aware that there have been complaints against the Permanente
Quarry for reasons of noise/pollution/traffic, but we feel it is
important to note that the facility pre-dates essentially all of the
residents now living in the area. Operations at the quarry have
become less noisy, less polluting, and no more traffic-intensive over
the years. If the facility is depressing property values or quality
of life, the price of homes along Oak Canyon Way (nearly as close to
the quarry as any) certainly don't reflect that.
Thank you for this opportunity to comment.
(Mr.) Jan Stoeckenius
Julia Ju-Wen Tien
(Mr.) Jan Stoeckenius & Julia Tien, P 0 Box 1807, Cupertino, CA 95015-1807
tel: 408-996-7467 (office) tel/fax: 408-996-2064 email: kite@orimp.com
2
Lauren Sapudar
From:
Sent:
To:
Subject:
Attachments:
Gary Latshaw <glatshaw@gmail.com>
Monday, February 29, 2016 8:58 PM
City Council; City Clerk; Cupertino City Manager's Office
Noise from Lehigh Cement -Consent Item #11
Reaction to the Sound Reports_Jan27 _2016.pdf; C_12_021_Lehigh Cement_20120122-1.pdf
Dear Council, Mayor, and City Manager - I do not believe that the County reports reflect the seriousness of the noise
problems associated with the Lehigh operation. I have attached the letter, which I sent to Supervisor Joe Simitian on
January 27th. I have been in contact with his office since then and I am told that he is still "reading" it.
In summary:
1. The studies involved should have included inputs from the community. Those inputs should have been documented.
2. The community inputs should then have been used to structure the scope of the study.
3. The study should have addressed the short-duration noises from the plant and not the L90 levels. This would have
been a logical conclusion given the apparent character of the citizen's complaints.
4. The study should have had long-term monitoring to capture the occasional, but disruptive night-time noises from the
plant.
5. The study should have included an examination of the facility and an assessment made of what equipments or
procedures could be introduced to reduce the noise impact on the community.
As a follow-up comment on item 5, at my encouragement the cities of Los Altos and Los Altos Hills sponsored an
effort by which an expert consultant, Dr. Jim Staudt made specific recommendations regarding the pollution emission
controls at the plant. Some of his recommendations became part of the Regulations under which the plant now operates.
This has reduced the air emissions from the plant.
A similar study should be done of the plant for noise pollution. An independent consultant should be hired to identify
equipment and operational procedures that would reduce the noise.
Fight for Renewable Energies! Save the global ecology; create jobs; eliminate dependence on foreign oil; reduce
military requirements
Gary Latshaw, Ph.D.
408-499-3006
1
Supervisor Joe Simitian
70 West Hedding Street
10th Floor
San Jose, Ca 95110
January 27, 2016
Reference: Noise complaints from Lehigh Southwest Cement Company's Operations
(1) Burns McDonnell's "Lehigh Southwest Cement Co. Sound Compliance
Study," dated December 2015 (B&M study);
(2) County of Santa Clara Department of Environmental Health "Noise
Monitoring Report of Findings for Lehigh Southwest Cement Company,"
December 30, 2016 (DEH Study); and
(3) dBF Associates' Letter, dated December 30, 2015
Dear Supervisor Simitian:
The two reports and Letter are totally inadequate in describing the sound propagation
from Lehigh Cement Plant and whether or not the sounds are disruptive to residents. Nor
do they fully examine if they are in compliance with the County's Noise Ordinance.
Residents in the area are frequently awakened in the evening by sounds that they attribute
to the plant!!! Yet, these studies do not indicate such serious disruptions
The County has failed to examine the specific complaints from residents. The
measurements were very limited:
• The measurements were only conducted over a few sites and only for a few
minutes at each site,
• The measurements were all conducted during the fall and do not represent what
might occur during summertime inversion layers,
• The operations of the site were not investigated and an inventory taken. The site
has continuous machinery, start-ups and stoppages of conveyer belts, kiln, rock
crushers, and many other heavy machinery.
If the effort had incorporated specific complaints from the public and the issues raised by
the complaints were addressed in the Work Plan (B&M study), we would all understand
the situation better and be able to take appropriate actions. In particular the public
complaints included:
• Noises that are significant enough to wake residents at night. Some of these
residents live 2-3 miles from the Lehigh facility.
• Noise that appears to be blasting, which is used in the mining process. The
blasting usually occurred in the early morning hours. It causes richter-2 levels
earth shakes,
• Humming sounds that are similar to a finger circulating the top of a wine glass.
• Occasional clanging noises.
• Many nights and particularly in the early Saturday and Sunday mornings (3 or 4
am), there is a swelling noise that sounds like a giant vacuum cleaner.
The situation is analogous to taking a car to a mechanic and complaining that there is a
noise when turning to the right. The mechanic checks the oil, the water, the computer
readout, and the brake fluid. The mechanic concludes that there is no noise when turning
right. The thoughtful reader will realize that the mechanic never drove the car or steered
the car to the right. He didn't even check the power steering fluid.
We quote from page 2-3 the B&N study "L90 is a common Lx value and represents the
sound level with minimal influence from short-term, loud transient sound sources." The
study states on page 4-3 "Sound emitted by operation of the Facility is mostly constant at
a given operating condition." B&M reveal a complete ignorance of the operations of the
cement plant-cement plants have varying activities and are far from "constant."
Complaints from residents often reveal a non-constant source of noise from various
intermittent operations at the Plant.
The Department of Health and Environmental Health also ignores the need for
measurements of short durations. Table 2 (Page 3 of 7) of their report sites the time limit
specifications that are in the County's own Noise Ordinance, but the report makes no
attempt either by measurement or analysis to determine whether the plant's sounds
comply with this aspect of the ordinance. The report does state that the only exceedances
were due to background noise "crickets, traffic."
Given the total lack of credibility of the studies performed, I suggest new studies:
• Hold a meeting with the public and invite residents to stipulate precisely their
complaints. These complaints should be recorded and published.
• Based on the complaints, and analysis of the Plant's operation a Work Plan should
be developed. Then, sound measurements should be taken at several locations
within the neighborhoods as well as the boundary of the plant.
• The measurements should be done over a length of time to ensure that potentially
disadvantageous meteorological conditions occur. The measurements should
proceed for at least a month.
• The measurements should occur during seasons in which sound propagation is the
greatest -when inversions occur.
• The measurements should include continuous dB, dBA, and sound recordings.
The sound recordings would allow identification of the source (e.g., bird, plane,
machinery (most likely from the cement plant)).
• The data should be analyzed for:
o Maximum levels, Li, Lio, and L90. The peak values should be analyzed for
compliance with the County Ordinance. This ordinance reflects the
significance of short bursts of noise that are often very disruptive to sleep
and relaxation. I will call it the presents of the "alarm-clock type noise"
o If wind speed measurements are made, they should be coupled with wind
direction measurements as well.
o The measurements should be taken when blasting is occurring.
o The measurements should be taken when suspect pieces of equipment are
operating.
o An expert in the physiological effects of sound and noise should analyze
the measurements.
I am confident a professionally conducted sound/noise study would result in a clear
understanding of the situation. These studies are simple distractions from arriving at
scientific understanding of the situation.
Sincerely,
~· I
Gary Latshaw, Ph.D.
11054 La Paloma Drive
Cupertino, California, 95014
(Located about 2.5 miles from the Lehigh Cement Plant)
Cc. Kristina Loquist (email)
Emissions Control Options for Lehigh Hanson
Cement Plant
Report C-12-021
to:
Breathe California of the Bay Area
1469.Park A venue
sari'19[e}CA 95126
January 22, 2013
City of Los Altos
One North San Antonio Road
Los Altos, CA 94022
Andover Technology Partners
112 Tucker Farm Road, North Andover, MA 01845
phone: (978) 683-9599; e-mail: staudt@AndoverTechnology.com
WWW·
Andover Technology Partners
112 Tucker Farm Road, North Andover, MA 01845
Confidentiality Notice
This report was prepared for the use of the client identified on the cover and may be subject to
confidentiality requirements.
www.AndoverTechnology.com
Contents
1.
2.
3.
Sections
Background
Objectives
Program Results
www.AndoverTechnology.com
Page
1
3
4
Background
Lehigh Cement operates a precalciner Portland cement kiln rated at 1,497,000 metric tons
of clinker per year ( 4535 metric TPD) in Cupertino, CA. Actual operation is roughly 6897 hrs/yr
and a total 1,399 ,692 tons of clinker per year. The kiln, shown in Figure 1, was placed into
service in 1981. Its primary air pollution control device has been a reverse-air fabric filter for
dust collection which has compartments vented to the atmosphere. Gaseous emissions (NOx,
CO, S02) and flow are monitored from some of the 32 vents on the fabric filter or in the
ductwork. There is also a fabric filter on the clinker cooler.
The kiln is subject to US EPA's National Emission Standards for Hazardous Air
Pollutants (NESHAP), which requires installation of Maximum Achievable Control Technology
(MACT) by August 2015 as well as Bay Air Quality Management District (BAQMD) rules.
Recently proposed BAQMD Regulation 9, Rule 13 sets limits shown below along with
monitoring requirements.
• 2.3 pounds NOx per ton of clinker produced averaged over 30 days
• 0.04 pounds PM per ton of clinker produced averaged over 3 source test runs
• 10 ppmv ammonia above baseline, dry at 7% oxygen averaged over 24 hours.
• 0.2 nanograms Dioxins/Furans (TEQ) per standard cubic meter, dry at 7% oxygen
averaged over 24 hours
• 55 pounds Mercury per million tons of clinker produced averaged over 30 days
• 3 ppmv HCl, dry at 7% oxygen averaged over 30 days
• 24 ppmv Total Hydrocarbons (THC), dry at 7% oxygen averaged over 30 days, or
alternatively, 12 ppmv Total Organic HAP, dry at 7% oxygen averaged over 30 days.
These limits have motivated Lehigh to install additional controls. Controls that have
been installed or will soon be installed include: selective non-catalytic reduction (SNCR) for
NOx control, activated carbon injection (ACI) for mercury and dioxin control, lime injection
(LSI) for acid gas control, mercury monitoring, modifications to the dust collector and
modifications to the vents to reduce the number of monitoring points and a 300 foot chimney.
WWW .AndoverT echnology.com
Figure 1. Lehigh Hanson Cement Kiln
www.AndoverTechnology.com
Objectives
The objectives of this effort are to provide the following:
Evaluate the plant to see iflower emissions are possible for the following pollutants:
• NOx
• S02
• Mercury
• Particulate Matter (PM)
If additional reductions are likely to be possible, determine what methods would be used
and their estimated cost.
www.AndoverTechnology.com
Program Results
The Lehigh Cement plant is a 1981 vintage precalciner cement plant that has baghouses
as its sole pollution control devices. The kiln baghouse, which is integral to the Kiln Mill Dust
Collector KMDC system, is used to collect kiln dust that is recycled back to the kiln pyro
system. Recycling cement kiln dust in this manner reduces solid waste that might otherwise
have to be disposed of and also more efficiently utilizes feed materials. The mill recently
installed a KM.DC shuttling system that bleeds some of the kiln dust from the pyro system,
which has the benefit of reducing mercury emissions. Table 1 shows average 2010 emissions
compared to the new BAAQMD limits that will take effect in September 2013 and the New or
Modified Source NSPS and the New Source NESHAP limits. Another source of PM emissions
is the clinker cooler baghouse, although this is not a source of other gaseous emissions.
To meet the new emission limits, Lehigh plans to (or has recently) install( ed) the
following:
• One activated carbon injection system for mercury (Hg) control
• A hydrated lime injection (LSI) system for HCl control
• A selective non-catalytic reduction (SNCR) system for NOx control
• A 300 foot chimney to improve dispersion of pollutant gases
Table 1. Emissions Rates for Lehigh Cement, New BAAQMD limits, NSPS and New NESHAP
Avg. 2010 NewBAAQMD New or Modified
Emissions1 or Title V limits NSPS or NESHAP
NOx 4.0 lb/ton clinker 2.3 lb/ton clinker 1.5 lb/ton clinker N
S02 1.15 lb/ton clinker 481 lb/hr 0.40 lb/ton clinker s
(2.3 lb/st**) p
PM 0.014 lb/ton clinker 0.04 lb/ton clinker 0.02 lb/ton clinker s
Hg 305 lb/million ton 55 lb/million ton 21 lb/million ton clinker N clinker clinker
Dioxin/Furan 0.2 ng/dscm 0.2 ng/dscm E
Total HC 24ppmv 24ppmv s
Total Organic HAP 12 ppmv 12ppmv H
PM 0.014 lb/ton clinker 0.04 lb/ton clinker * 0.02 lb/ton clinker A
HCl 7.63 lb/ton clinker 3ppmv 3 ppmv p
*The final Portland Cement NESHAP established a PM limit on existing kilns of0.07 lblton clinker
**estimated by dividing by 4535 metric tons per day and 1.1 short ton per metric ton and multiplying by
24 hrs per day
1 BAAQMD, "Bay Area 2010 Clean Air Plan Stationary Source Control Measure SSM-9 -BAAQMD Regulation 9,
Rule 13, Nitrogen Oxides, Particulate Matter, and Toxic Air Contaminants from Portland Cement Manufacturing,
Staff Report", July 2012
www.AndoverTechnology.com -
Executive Summary of Results
In reading the results of this report it is important to consider that this was a high level
study that did not perform detailed engineering analysis. The objective was to examine ifthere
are any technical options for additional reductions that might be examined further or if there are
emission reductions that could be had at low or no cost that may not yet be reflected in the
permit. This is not intended to "second guess" the work that others have done so far, but to look
for opportunities that may be available for additional reductions, and when additional reductions
will require significantly more cost, to explain why.
It is my opinion that improvements (reduction) in the emission limits for the Lehigh
Cement plant might be possible for the following pollutants and at the following cost.
NOx
Some improvement in the NOx emission limit may be possible through the following means:
• SNCR emission reduction will vary, but is roughly 50% on average for cement kilns. It
may be possible to achieve slightly lower NOx emissions than 2.3 lb/ton clinker. This
would not require any additional capital cost, but would entail modest additional
operating cost.
• Mixing Air Technology-This could potentially improve emissions somewhat at a capital
cost of roughly $520,000. It can also improve CO and S02 emissions.
• Use of natural gas in the precalciner-It is not possible at this time to determine the
capital cost, but it would likely be quite modest since gas is already fired for start up.
The increase in operating cost would result from the differential cost in fuel. This would
also contribute to a modest reduction in PM and S02 emissions.
For this reason I believe that there are a few options to examine that might offer low capital
cost approaches to a reduction in NOx emission rate to perhaps about 2.0 lb/ton clinker or
less.
S02
The use oflime injection for control ofHCl will also reduce S02 emissions. This is not
currently captured in the emission limit of the plant. It would be reasonable to expect
roughly 50% reduction in S02 emissions with the roughly 75% reduction in HCl emissions.
These emission reductions are available at no additional cost beyond what is committed to
for compliance with the NESHAP limit for HCI.
Mercury
Current plans are to use activated carbon injection and a bleed of kiln dust to reduce
mercury emissions. It is my opinion that achieving the new or modified source Hg emission
rate of 21 lb/million ton clinker would likely require either an additional baghouse (at a
substantial capital cost) or bleed of nearly all of the kiln dust. I do not know what the
economic impact of bleeding 100% of the kiln dust would equate to, but it might make it
necessary to landfill some of the kiln dust because there are limits to how much kiln dust
may be used in the final cement product. For this reason significant additional reductions in
emissions beyond the limit for existing kilns (55 lb/million ton clinker) cannot be achieved
without a substantial additional capital investment.
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PM
BAAQMD has established an emission limit of 0.04 lb/ton clinker, and this is being
challenged by Lehigh Cement. The 2010 emissions rate was well below this limit (0.014
versus 0.04 lb/ton clinker) and therefore the limit appears to be achievable already.
Although addition of lime injection and activated carbon injection will result in a slight
increase in the solids loading to the kiln baghouse, these generally have negligible impacts
on outlet emissions for a fabric filter. It is recommended that some form of continuous
monitoring be used for PM emissions -either in the form of opacity monitoring or a PM
CEMS.
In the following sections, more detailed examination of each of these pollutants will be
provided which will describe why these conclusions were reached.
www.AndoverTechnology.com -
1.0 NOx Emissions
NOx emissions from cement kilns are primarily the result of the combustion of fuel in the
kiln. To a lesser extent they are related to nitrogen compounds in the feed material. Feed
materials may also play a role in impacting NOx through the pyroprocessing necessary for the
particular feed materials. Figures 1 and 2 show NOx emissions (in lb/ton clinker) for precalciner
kilns based upon year on line and annual clinker capacity, respectively. The data is based upon
2002 National Emissions Inventory (NEI) data and capacity data from the Portland Cement
Association (PCA). As shown, there is significant scatter in the data with a handful of outliers;2
however, some trends can be observed. For precalciner kilns that commenced operation in the
time frame of the Lehigh Cupertino kiln, emission rates average around 3.5 lb/ton clinker. For
facilities in the size range of the Lehigh Cupertino plant, emission rates average around 2-3
lb/ton clinker. At roughly 4.0 lb/ton of clinker (the average for January-June 2012), the Lehigh
Cupertino kiln is somewhat above average. The new BAAQMD limit will be 2.3 lb/ton of
clinker, which is less than 50% reduction of NOx.
Figure 1. NOx emissions ~lb/ton clinker)
versus year on line.
r·~:.:: ......... ·-·-····-···-·····--................... -···-·····-· · -···-········-·-1
1 9.oo I
B.00 t····-·······································-·--···························-···········-··············;::::::::::::::::::::c::::::::.::: .......... ,
7.00 +---·------···--·------·-··-·------·----·-·-·!
6. 00 i·· ........... .4;=-~tt.l.\l.\!K.~.'::'.'_ ............ ~L. ................................. 1_-:::: . .!_~.":'_e::_;_:_:r_::.::.J
5.00 +---·-·-------··-···-----·----·-·-··-·------------
4.00 +······-·············-·····················-·-······~:---,;;-·························~,--
3.00 +--------·-·-----··-"-··-"'-"ii>--",,,__::--
2.00 ..,. ................................................................................................. .
1.00 +--·---·····--·--···-----··-·----·-··-·-------·-··----·---
I o.oo +·······-···································-,·······················,············-·······-r·-·-··············"1>-··········-····
l .......... ~9.5..°.. 1960
1970 1980 1990
............ .Y:.~E-~~-~.~~e 2000 2010
Figure 2. NOx emissions (lb/ton clinker)
versus capacity. 3
["................................................................................... ······-························--··························· ······················1
i 10.00 .. --·-·-···········-········-··-······················ .................................. ..................... I
! 9.00 ····-·· ··········-···~----··············~··· ..................................................................... .
8.00 ·--·---------·-·--·-------------------
6.00 ~:.=~~--~~::·~·~:[~~-~~~;-'.:(;;;;t=:~:=
4.00
~.oo ·
2.00 ·t································;;"····•'--<!'····'·:-······W·········"=-""==-································
500,000 1,000,000 1,500,000 2,000,000 2,500,000 eapacitytpy ........................................................................... -·--········--·····----·---
NOx emissions maybe reduced in one of two ways -
• Reducing the amount of NOx formed in the combustion process, or
• Reduction of the NOx after it has been formed through post-combustion methods
2 As shown, some of these outliers have unreasonable emission rates (like zero) and generally should be ignored
because they are likely the result of errors in the input data.
3 US EPA Industrial Sector Integrated Solutions model documentation, Memo from J. Staudt to R. Srivastava, S,
Vijay and E. Torres, Re: NOx, S02 and C02 emissions from Cement Kilns (Emissions Memo)-revised
from comments, March 10, 2009
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1.1 Reducing the amount of NOx formed
Combustion occurs in two places in a precalciner cement kiln: 1) the precalciner section;
and 2) the rotary kiln.
Roughly 60% of the fuel is burned in the precalciner of a modem precalciner cement kiln.
For older kilns this amount may be less, perhaps in the range of 50%. Because the precalciner
combustion is at a lower temperature, most of the NOx formed in the precalciner is fuel NOx.
In the rotary kiln, thermal NOx plays a more significant role in total NOx formation because of
the higher temperature. Methods to control NOx formation are described in more detail below:
Rotary Kiln -
Low NOx Burner with Indirect Firing
The primary burner in the rotary kiln typically fires coal, petroleum coke, or natural gas.
In some kilns (not in the Cupertino kiln) alternative fuels (such as tires, solvents, or other waste
materials) may also be burned in the rotary kiln, but not through the primary burner. Because
thermal NOx plays an important role in NOx formation in the rotary kiln, coal is actually
preferred to natural gas from the perspective ofNOx control. Natural gas requires firing to a
higher gas temperature to heat the materials because the flame is not as luminous. As a result, a
conversion to natural gas is unhelpful with respect to NOx control.
The primary burner utilizes an indirect firing system, where the pulverized fuel (coal or
coke) is not sent directly from the fuel mill to the burner, but to an intermediate fuel bin and
feeder system. The advantage of indirect firing for NOx control is that it permits lower primary
air levels in the near burner field, which reduces the amount of NOx formed when using a burner
that permits lower excess air for lower NOx (this is also known as a low NOx burner with
indirect firing). Based upon discussions with BAAQMD, 4 the Lehigh kiln is equipped with
indirect firing. So, further reductions by this method are not possible.
Mid Kiln Firing (MKF)
MKF is when fuel is introduced to the rotary kiln at the mid-point of the kiln. Although
tires are commonly introduced in this manner, 5 coal, coke or other fuel may also be introduced at
this point. MKF has been shown to reduce NOx emissions in the rotary kiln on the order of
30%, and sometimes more. This is possible because it reduces the amount of firing needed in the
4 Telephone call with Robert Cave and Thu Bui, 1/10/13
5 The advantage of tires are that they can be used to offset purchased fuel (coal) and a tipping fee may be received.
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primary burner, thereby reducing NOx formation at the hottest part of the kiln where thermal
NOx formation is the highest. The Lehigh kiln does not employ MKF.
Mixing Air Technology (MAT)
MAT is the introduction of burnout air downstream of the primary burner or downstream
ofMKF. With MAT it is possible to operate the primary burner and MKF at lower excess
oxygen levels, thereby reducing the formation ofNOx. MAT also offers the potential for lower
CO emissions and lower S02 emissions (through promotion of sulfate formation and the CaS04
reaction) because it can promote a more oxidizing environment. MAT can reduce NOx
emissions by roughly 30% and it can be used to enhance NOx reduction from other technologies
such as a low NOx burner with indirect firing. The Lehigh kiln does not employ MAT.
Figure 3. Mixing Air Technology 6
· Without mixing air With mixing air
6 Hansen, E., ""Staged Combustion for NOx Reduction Using High Pressure Air Injection", IEEE/PCA Conference
2002
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Figure 4. Staged Combustion Calciner7
Precalciner -
Staged Combustion
Calciner (SCC)
SCC reduces NOx through
staged combustion in the
precalciner, where a fuel-rich
(oxygen deficient) zone is
followed by a burnout zone as
shown in Figure 3. This
technology results in a reduction of
NOx that will vary by application,
but is on the order of 30%. On an existing kiln it is necessary to modify the precalciner to allow
for both the fuel rich zone and the burnout zone. This apparently was considered at the Lehigh
Cement plant but was ruled out due to cost, estimated at roughly $15-$20 million.8 Table 2
summarizes experience with SCC on some U.S. kilns.
T bl 2 S a e . ummaryo fNO P f x er ormance o r sec· us Kil Ill . . ns
Source/Location NOx Uncontrolled NOx Controlled Efficiency
(lb/t) (lb/t)
11 US kilns(from Table 7-2) NA 2.2-3.3 NA
(avg. 2.7)
Florida Rock 3.5 3.0 -w/o tires 17% -w/o tires
1.5-2.5 (midpoint 2.0) -w/ tires 43% -w/ tires
Suwannee American NA 2.2-2.6 (range) NA
2.4 (midpoint)
Titan American NA 2.0 NA
Lone Star 2.8 1.8 35%
Cemex Santa Cruz 9 NA 2.5 (0% coal to reducing zone NA
1.7 (50% coal to reducing zone) 32%
1.4 (100% coal to reducing zone) 44%
1.8 (midpoint) 28%
Alternative Control Techniques Document Update -NOx Emissions from New Cement Kilns, EPA-453/R-07-
006, November 2007
7 Alternative Control Techniques Document Update -NOx Emissions from New Cement Kilns, EPA-453/R-07-006,
November 2007
8 BAAQMD, "Bay Area 2010 Clean Air Plan Stationary Source Control Measure SSM-9 -BAAQMD Regulation 9,
Rule 13, Nitrogen Oxides, Particulate Matter, and Toxic Air Contaminants from Portland Cement
Manufacturing, Staff Report", July 2012, p 21
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Fuel Change in Precalciner
Because most NOx formed in the precalciner is fuel NOx, NOx may be reduced though
fuel changes to natural gas. The level ofNOx reduction will depend upon a number of variables
relating to how the facility is currently operated, but since up to 60% of the fuel is typically
burned in the precalciner, a significant reduction may be possible. This will also reduce S02 and
PM emissions. The capital cost would likely be fairly modest since the plant already burns
natural gas. The operating cost will depend upon the difference in fuel cost between natural gas
and coal or other fuel (pet coke) burned in the precalciner.
1.2 Post Combustion NOx Control Methods
There are two methods of post combustion NOx control, Selective Catalytic Reduction
(SCR) and Selective Non-Catalytic Reduction (SNCR)
There is very little experience with SCR on cement kilns, and utilizing this technology at
Lehigh Cement would be costly and will not be examined further.
Lehigh Cement is planning to install an SNCR system. SNCR systems are capable of
roughly 50% NOx reduction on cement kilns, although there may be some variation :from kiln to
kiln.
1.3 Options for NOx reduction at Lehigh Cement Cupertino
The facility already has committed to reduce NOx emissions to 2.3 lb/ton clinker :from
roughly 4 lb/ton clinker. 9 It may be possible that a lower emission limit could be justified, but it
would not be dramatically lower since NOx reduction of 50% would be about 2.0 lb/ton clinker.
This would not require any additional capital cost, but would require a modest amount of
additional reagent. Assuming urea as a reagent, $600/ton of urea and 35% chemical utilization,
the incremental cost is about $1,100/ton ofNOx controlled.
Other options for NOx reduction that are moderate in cost may include mixing air
technology and perhaps burning natural gas in the precalciner. Mixing Air Technology
equipment and installation is estimated to cost roughly $520,000 in 2008 dollars, or $521,000 if
9 A review of source test data showed a range of emission rates. 4 lb/ton clinker is the average for 2010.
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escalated to August 2012 using the Chemical Engineering Plant Cost Index (CEPCI). 10 In
addition, there would be an allowance for down-time on the kiln necessary to install the
equipment. Recent operating data shows 6897 hours per year of operation, which means that
installation of mixing air technology would likely be possible without impact to kiln operation.
Utilizing natural gas in the precalciner (but not in the rotary kiln, however) could
possibly be performed with little or no capital expense, depending upon the current design of the
precalciner burners and the natural gas supply to the kiln.
A more expensive approach for reducing NOx is perhaps Mid Kiln Firing (MKF). Using
the cost estimating approach used in US EPA' s ISIS model 11, the capital cost can be estimated as
roughly $4.5 million (2005 dollars) or using the CEPCI to escalate to August 2012 dollars $5.6
million, to provide a roughly 30% reduction in NOx. The MKF system includes mixing air
technology. Because of the cost and the fact that tires would not be burned to reduce fuel costs,
MKF is not a technology that is likely to provide reductions at low cost.
In summary, I believe it may be possible to find ways to achieve a somewhat lower NOx
emissions, of perhaps 2.0 lb/ton of clinker or less, without a large capital outlay. But, large
reductions in NOx emissions are not possible without a significant capital outlay. Although
some of these methods, such as mixing air technology, are expected to provide 30% reduction on
average, in those cases where other measures have already been taken to reduce NOx, the
emission reduction may be less than 30%. So, from the perspective of establishing an emission
limit we might not want to take the full 30%. It is unclear what the impact would be on fuel cost
to bum natural gas in the precalciner and the level of NOx reduction is also unclear at this point.
'0 US EPA Industrial Sector Integrated Solutions model documentation, Memo from J. Staudt to R. Srivastava, S,
Vijay and E. Torres, Re: Costs and Performance of Controls -revised from comments s, March 10, 2009, p 10
II Ibid, p. 7
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2.0 S02 Emissions
S02 emissions are primarily released by the raw materials as they are heated. Most of the
sulfur in the fuel is captured in the product as the flue gas from the kiln comes in contact with
free lime in the precalciner. For this reason the sulfur in the raw materials has a significant
impact on the S02 emissions. The kiln type also has an impact. As a precalciner kiln, the S02
emissions are lower than for long kilns (kilns without a separate preheater) because the S02
released by the raw materials comes in good contact with the alkaline material in the preheater
and calciner. As shown in Figure 5, which shows average Portland Cement kiln S02 emissions
as a function of market location and kiln type, S02 emissions from Portland cement kilns in the
San Francisco market as EPA has defined it in development of the NESHAP 12 are generally
lower than in other markets. This is no doubt a result of the sulfur content of the raw materials.
Figure 5. Average S02 emissions (in lbs/ton clinker) by kiln type and location 13
25.00 -.---------------------------------
1111 PC 11 PH
20.00 -+----------------------..------]
1111 Dry ill Wet
5.00 ------------111-I
Since it is not practical to change raw materials, especially limestone, reducing S02
entails add-on controls. Tail-end S02 control systems include lime injection, which is already
12 The San Francisco market as it is used here is all of northern California -not just the Bay Area.
13 US EPA Industrial Sector Integrated Solutions model documentation, Memo from J. Staudt to R. Srivastava, S,
Vijay and E. Torres, Re: NOx, S02 and C02 emissions from Cement Kilns (Emissions Memo)-.revised
from comments, March 10, 2009, pg. 15.
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I
planned for HCl control, and scrubbers. Because of the high capital cost of S02 scrubbers, they
will not be examined.
Reduction of S02 emissions is a co benefit of the planned HCl control approach-lime
injection. Experience with lime injection has demonstrated that it captures HCl somewhat more
efficiently than S02• This is because HCl is a more reactive acid. Thus, a 75% capture rate for
HCl with lime injection14 will result in an S02 capture rate that is somewhat lower than 75%.
There are a number of factors that impact this, such as injection temperature and the relative
concentrations of HCl to S02; however, an S02 removal rate of 50% seems like a reasonable
estimate of the likely S02 emission reduction ifthe HCl emission reduction is in the range of
75%. The actual S02 emission reduction can be verified once the lime injection system is
installed. At this time this improvement in S02 emissions is not captured in the plant's emission
limit, and therefore, these reductions in S02 emissions are at no cost since they are a cobenefit of
the HCl reduction system.
The ambient S02 levels should also be improved by the new 300 foot chimney. So,
between the reduction in S02 emission rate and the impact of the chimney, ambient S02 levels
should see an improvement.
S02 is therefore an area where there will be some significant gains as a result of what is
already planned for HCl control. For this reason a significantly lower S02 limit could likely be
implemented with little or no cost to the Lehigh Cupertino cement plant. My review of
emissions tests since 2007 confirm that at the moment, S02 emissions tend to be well below the
current emission limit of 481 lb/hr.
14 75% is roughly what is expected for HCl based upon past HCl levels and the required emission rate per the new
Portland cement NESHAP.
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3.0 Mercury Emissions
Mercury that is emitted from the chimney comes from mercury contained in the fuel and
mercury contained in raw materials. A simple mass balance will show that mercury that
originates in the fuel or the raw materials must go into the product, become a solid waste, or go
up the chimney, but the mass balance in the process is complicated by the fact that mercury at
high temperatures is volatilized. Figure 6 demonstrates the complexity of the mercury mass
balance. The high temperature pyroprocessing necessary to make clinker ensures that the
mercury is in a vappr state and does not become part of the clinker. As a result, mercury
captured in cement kiln dust that is returned to the kiln for pyroprocessing eventually goes up the
chimney, and the mercury emissions to the air equals the mercury introduced by the fuel and raw
materials.15 This returned mercury actually contributes to a concentrating mechanism that will
result in more mercury actually being circulated through the kiln in any period of time than
actually is input in that time. This concentrating mechanism is a function of the degree to which
the mercury that enters the kiln dust collector (baghouse) passes through the kiln dust collector
(and into the atmosphere) or gets returned to the kiln. If, for example, half of the mercury that
enters the baghouse exits the baghouse with the exhaust gas and the other half ends up in the kiln
dust, then the mercury returned to the kiln must equal the amount of mercury that is introduced
from fuel and raw materials as well as the mercury that is released up the chimney.
The mercury capture plan for the Lehigh Cement plant involves capturing the mercury
that is in the cement kiln dust in the baghouse. Activated carbon injected upstream of the kiln
dust collector will increase the proportion of mercury that ends up in the kiln dust. A portion of
the cement kiln dust is then bled off from the kiln dust collector and not reintroduced to the kiln
-it might be disposed in a landfill 16 but it is preferably used in the concrete product.17 This
reduces the amount of mercury that is sent back to the kiln, as in Figure 7. If all of the kiln dust
were reintroduced to the kiln, then the mercury entering the kiln dust collector would increase to
the point where there would be no actual reduction in mercury emissions to the atmosphere. So,
bleeding off some portion of the kiln dust is necessary to achieve a reduction in mercury
emissions to the atmosphere. The percent reduction in mercury emissions to the atmosphere will
15 In fact, this is how the cement kiln NESHAP limit was developed-by measurement of mercury in the input
materials rather than by stack tests because more and better data was available on the mercury inputs. This
also assumes all kiln dust is readmitted to the kiln, which is a good assumption for most Portland cement
kilns.
16 This is a safe way to dispose of it, because lots of testing has shown that the mercury is immobilized.
17 CALTRANS permits up to 5% limestone or kiln dust in the cement product
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therefore depend upon both the capture efficiency of the activated carbon system and the amount
of kiln dust that is not reintroduced to the kiln.
Figure 6. Mercury mass balance in a cement kiln with 100% kiln dust returned to the kiln
Mercury in
kiln
Mercury in kiln dust
Kiln dust
collector
(baghouse)
Mercury out
chimney
Figure 7. Mercury mass balance with activated carbon and bleed of kiln dust from existing kiln
dust collector for mercury control
Mercury in
kiln
Activated
carbon in
Mercury in kiln dust
Kiln dust
collector
(baghouse)
Mercury out
chimney
Mercury,
carbon and
kiln dust
out
Another option is to have a second dust collector (baghouse) downstream of the primary
kiln dust collector, with an activated carbon injection system between the two dust collectors, as
shown in Figure 8. The second dust collector does not need to be as large as the primary dust
collector since it is only for capturing activated carbon. This would avoid the need to bleed off a
portion of the kiln dust from the primary kiln dust collector and would also allow for higher
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mercury capture rates. It would also likely result in lower PM emission rates since there are two
dust collectors. The disadvantage of this approach is that it has a significantly higher capital cost
and requires operation of two dust collectors -each of which has a pressure drop and requires a
booster fan and the associated electrical load. But, a significant advantage to this approach is
that there is no concern about mercury or activated carbon contamination in the product.
Figure 8. Mercury mass balance using activated carbon and a second baghouse to control
mercury em1ss10ns
Mercury out
Mercury in
kiln Kiln dust
collector
(baghouse)
Second
baghouse
chimney
Mercury in kiln dust Mercury and
activated carbon
out
To disposal
Reducing mercury emissions from the current rate of roughly 305 lb/million ton clinker
to 55 lb/million ton of clinker is an 82% reduction in mercury. By my estimates, this could be
achieved using the single kiln dust collector by
• An 82% capture rate of mercury by activated carbon, and a bleed of 100% of the kiln dust
from the kiln dust collector, or,
• a 90% capture rate of mercury by activated carbon and a bleed of roughly 51 % of the kiln
dust, or
• a 95% capture rate of mercury by activated carbon and a bleed ofroughly 24% of the kiln
dust, or
• A 97% capture rate of mercury by activated carbon and a bleed of 14% of the kiln dust
from the kiln dust collector, or
• some other combination of capture efficiency and bleed of the kiln dust that will result in
a net 82% capture efficiency
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On the other hand, reducing mercury emissions from the current rate of roughly 305
lb/million ton clinker to 21 lb/million ton of clinker is just over 93 % reduction in mercury. By
my estimates, this could be achieved using the single kiln dust collector by:
• A 93 % capture rate of mercury by activated carbon, and a bleed of 100% of the kiln dust
from the kiln dust collector, or,
• A 95% capture rate of mercury by activated carbon and a bleed of 70% of the kiln dust
from the kiln dust collector, or
• A 97% capture rate of mercury by activated carbon and a bleed of 41 % of the kiln dust
from the kiln dust collector, or
• some other combination of capture efficiency and bleed of the kiln dust that will result in
a net 93 % capture efficiency
So, higher activated carbon injection system capture efficiencies will result in lower
bleed rates. Higher activated carbon injection system capture efficiencies are achieved through
higher activated carbon injection rates; however, activated carbon injection systems have
practical limitations to the level of emission reduction that is possible. There is no accepted
industry-wide number for this. It is my opinion that something above 90% mercury capture with
activated carbon can reliably be achieved, but it is less certain if capture efficiencies of 95% or
greater can reliably be achieved day in and day out.18 Therefore, a mercury emission limit equal
to the New Source limit of 21 lb/million tons of clinker would likely be possible only with a
second baghouse or with bleeding nearly all of the kiln dust. As will be shown in the next
section, a second, polishing baghouse would cost in the range of $20-$24 million.
Lehigh Cement's current plans do not include another baghouse. They are modifying the
structure of the kiln and clinker cooler baghouses and the vents to form a common exit location
that will be ducted to a 300 foot chimney, and according to the BAAQMD Staff Summary
Report, the estimated cost for this modification to the kiln mill dust collector and modifications
to the clinker cooler dust collector is roughly $28.5 million.19
18 This is not to say that it can't be done; however, there simply is not a lot of published data available for long-term
operation of activated carbon systems at such high capture efficiencies. Moreover, the measurement
methods have been evolving as well. So, with time there should be more information available to assess
whether or not very high capture rates of over 95% can reliably be achieved.
19 BAAQMD, "Bay Area 2010 Clean Air Plan Stationary Source Control Measure SSM-9 -BAAQMD Regulation
9, Rule 13, Nitrogen Oxides, Particulate Matter, and Toxic Air Contaminants from Portland Cement
Manufacturing, Staff Report", July 2012
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4.0 Particulate Matter (PM)
There are two sources of PM-the kiln baghouse and the clinker cooler baghouse. At
this time the plant continues to operate the existing kiln baghouse (the primary fabric filter) and
the clinker cooler baghouse. According to BAAQMD, the facility has been able to maintain PM
emissions below the new rate of 0.04 lb/ton clinker and my review of several stack testing
reports confirms that. 20 I have not been able to determine the details of the filter media.
Assuming that the fabric filter uses "state of the art"21 filter media, the only alternatives for
further PM reductions are: 1) a polishing fabric filter (usually used to capture sorbent, such as
activated carbon), or; 2) improyed monitoring of the existing fabric filter to assure that periods of
high PM emissions (such as from leaks in filter media) are quickly identified and corrected.
4.1 Polishing Fabric Filter
This is really something what would be considered to gain other benefits, such as higher
mercury removal, but the cost is shown in any event. The estimated cost of a polishing22 pulse-
jet fabric filter that could be used to capture the activated carbon as well as PM that escapes the
primary fabric filter is shown in Table 3. Assumptions used in this estimate are:
• 360,000 dscfm
• 10% moisture
• Net Air to cloth ratio of 6.0 23
• Gas temperature of 320°F
• Duct runs of 50 feet each way (short ductwork) and 220 feet each way (long ductwork)
As a result of the high cost of a new fabric filter shown in Table 3, this is not an attractive
option for reducing PM emissions.
20 I reviewed stack test reports from 2007 to 2012 made available by BAAQMD through a Public Records request.
21 Based upon what BAAQMD reports they have been told by the plant. See Footnote 4
22 Used after the current, primary baghouse that removes most particulate matter and it therefore has a much higher
air to cloth ratio than the primary baghouse.
23 This is net of compartments being out of service for cleaning
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Table 3. Estimated cost of a polishing fabric filter
Short ductwork Long Ductwork
ACFM 594,000 594,000
Baghouse (installed including steel) $9,099,016 $9,099,016
Ash Handling $1,099,741 $1,099,741
Booster Fans $462,692 $462,692
Electrical $805,076 $805,076
Ductwork short $674,830
Ductwork long $3,619,482
Foundations $529,046 $529,046
TPC $12,670,400 $15,615,052
Gen Facil $633,520 $780,753
Eng. Constr Mgt $1,267,040 $1,561,505
Proj Contingency $2,185,644 $2,693,596
Total Plant Cost Estimate (2006 $) $16,756,604 $20,650,906
Pre Production Costs $73,262 $80,623
Inventory Capital $253,408 $312,301
Total Capital Requirement (2006 $) $17,083,273 $21,043,830
2012 Total Capital Requirement $19,719,623 $24,291,387
Maintenance (Fixed Operating Cost) $380,112 $468,452
Variable Operating Cost $499,028 $499,028
Estimated using algorithms developed for US EPA's Clean Air Markets Division to
estimate cost of polishing pulse-jet fabric filters. 24
4.2 PM Monitoring Options
PM emissions are currently measured with periodic stack tests rather than continuously,
and the final EPA NESHAP for Portland Cement kilns only requires periodic stack tests. 25
Periods of high PM emissions may result from leaks in filter media or plant transients that cause
unusually high PM excursions that are not captured during the periodic stack tests that are
performed when the plant is generally well controlled. Continuous monitoring will enable plant
personnel to quicldy identify temporary periods of high PM emissions and address any problems
that cause these temporary high PM emissions. Options for providing improved PM emissions
assurance include:
• Opacity monitors-these measure the optical density or transparency of the flue gas
typically in percent and provide a relative indication of PM emissions. They have
been widely used for providing an indication of PM emissions. The output of these
24 Andover Technology Partners, "TOXECON Cost Estimates for Coal-Fired Boilers" DRAFT, December 2006
25 This is a revision from the proposed rule that required PM CEMS. The decision was based upon ability to
correlate emissions against stack samples for very low emitting sources.
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devices are in terms of percentage of optical transmittance. Because they do not
correlate as directly to the PM emission rate as PM CEMS, PM CEMS have become
favored recently, at least for power plants. BAAQMD has recommended an opacity
limit of 10%. 26 Therefore, an opacity monitor should be required as a minimum
measure for monitoring PM emissions.
• PM CEMS -more recently, BP A has been requiring PM CEMS for power plants.
These can provide an output that is directly correlated to PM emissions concentration
(such as milligram per actual cubic meter) and are therefore favored for measuring
PM emissions. The originally proposed Portland cement NESHAP required PM
CEMS but the final rule did not.
• Bag leak detectors -While not used for compliance reporting, these are used by
facility owners to quickly identify leaking filter media.
As a result, opacity monitoring should be required as a minimum, with PM CEMS to be
examined further. Based upon conversations that I have had with some CEMS suppliers, a PM-
CEMS is expected to cost in the range of $200,000 to cover equipment, installation, and start up
testing/calibration. Opacity monitors will cost a fraction of that.
26 BAAQMD, "Bay Area 2010 Clean Air Plan Stationary Source Control Measure SSM-9 -BAAQMD Regulation
9, Rule 13, Nitrogen Oxides, Particulate Matter, and Toxic Air Contaminants from Portland Cement
Manufacturing, Staff Report'', July 2012
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