HomeMy WebLinkAboutCOUNCIL - AGENDA ITEM - 09/02/2014 - RESOLUTION 2014-080, ADOPTING THE RECOMMENDATIONSAgenda Item 17
Item # 17 Page 1
AGENDA ITEM SUMMARY September 2, 2014
City Council
STAFF
Melissa Hovey, Senior Environmental Planner
SUBJECT
Resolution 2014-080, Adopting the Recommendations of the Air Quality Advisory Board Regarding Comments
to Colorado Department of Public Health and Environment on the Draft Construction Permit 13LR2446 for
Martin Marietta Materials, Inc. Hot Mix Asphalt Plant.
EXECUTIVE SUMMARY
The purpose of this item is to approve comments developed by the Air Quality Advisory Board and staff based
on public input and technical review of permit documentation to be submitted to Colorado Department of Public
Health and Environment regarding the draft air permit for the Martin Marietta Materials, Inc. hot mix asphalt
plant.
STAFF RECOMMENDATION
Staff recommends adoption of the resolution.
BACKGROUND / DISCUSSION
The Colorado Department of Public Health and Environment - Air Pollution Control Division (CDPHE-APCD)
requires hot mix asphalt plants to obtain air permits and adhere to requirements for air emission controls, limits
on annual asphalt production, and other reporting, operating, and maintenance requirements. On August 4,
2014, CDPHE-APCD issued a draft Construction Permit No. 13LR2446 on for the Martin Marietta Materials,
Inc. (MMM) hot mix asphalt plant located at 1800 North Taft Hill Road, Fort Collins, CO.
This asphalt plant is located outside of City limits in unincorporated Larimer County, and within the City’s
Growth Management Area. A portable asphalt batch plant has been located on or near the current site or on
the adjacent gravel mining site to the west, on several occasions for various lengths of time over the last four
decades. The existing plant was moved to its current location in the spring of 2011 by its previous owner. The
Larimer County Board of County Commissioners originally approved a Special Review for the plant under its
Land Use Code in 1985. The Board approved an amended Special Review to locate the plant at its current
location in March 2009.
Martin Marietta Materials, Inc. acquired the gravel mining operations and the asphalt plant in December 2011.
In 2013, MMM applied for a revision to their air permit to convert the asphalt plant from a “portable” plant (one
that moves at least every two years), to a “stationary” plant. MMM estimates that the quantity and quality of
the gravel from the adjacent mining operations can support the asphalt plant for several years.
Agenda Item 17
Item # 17 Page 2
CDPHE-APCD has completed its review of the air permit application and has made a preliminary
determination of approval of the application. CDPHE-APCD has also determined that this permitting action is
subject to a 30-day public comment period per Colorado Regulation No. 3, due to the following reason(s):
permitted emissions exceed public notice threshold values in Regulation No. 3, Part B, Section
III.C.1.a (25 tons per year in a non-attainment area and/or 50 tons per year in an attainment area)
the source is requesting a federally enforceable limit on the potential to emit in order to avoid other
requirements.
The public comment period concludes on September 3, 2014.
Local citizens, primarily from the neighborhoods surrounding the asphalt plant, have expressed concerns with
air emissions from the plant. These citizens are concerned with odors, dust, volatile organic compounds, and
hazardous air pollutants being emitted from the plant. In January 2014, concerned citizens formed an
advocacy group named the Citizens Against Asphalt Toxins (CAAT). Members from this group have made
presentations to City Council, Larimer County Board of County Commissioners, the City’s Air Quality Advisory
Board, the County’s Environmental and Science Advisory Board and presented testimony at the Public
Listening Session hosted by the City in May.
City Council members and City staff have been engaged in responding to citizen concerns regarding the
asphalt plant for over a year. These actions include advocating to CDPHE to conduct a public hearing on the
draft air permit, hosting a Public Listening Session with CDPHE, and committing to conducting a review of the
draft air permit.
The City also collaborated with Larimer County to procure the services of an air quality professional consultant
to assist with review of the draft air permit. Air Resource Specialist, Inc. was tasked to:
review the modeling analysis for completeness and accuracy as well as input assumptions used in the
dispersion modeling,
review the draft permit for compliance with all regulatory requirements,
review the analysis with respect to hazardous air pollutants,
review the air permit with respect to air monitoring and other compliance requirements.
The City’s Air Quality Advisory Board (AQAB) has been actively engaged in the air quality issues pertaining to
the asphalt plant. The AQAB has been preparing to review the draft air permit and provide recommendations
to Council within the 30 day public comment period. The AQAB completed its review of the draft permit on
August 25, 2014 and constructed comments which are submitted as Exhibit A to the proposed Resolution.
The AQAB recommends that its comments be communicated to CDPHE by City Council. The AQAB based its
comments on the following items:
Supporting documentation and analysis provided by CDPHE-APCD with the draft air permit,
Results provided by Air Resource Specialists on their technical analysis of the draft permit on August
18, 2014,
Information provided by CDPHE-APCD and citizens at the public listening session hosted by the City
on May 21, 2014,
Technical discussion at AQAB subcommittee meeting on May 16, 2014,
Information received during a tour of the plant on May 16, 2014,
Information received from the CAAT and MMM provided at the board’s April 21, 2014 meeting,
Atmospheric science and air quality regulatory expertise of City staff and board members.
Agenda Item 17
Item # 17 Page 3
Staff concurs with the board’s recommended comments and notes the comments support the following City
Policies:
2011 City Plan:
Principle ENV 8: Continually improve Fort Collins’ air quality.
Policy ENV 8.3 - Employ a Citywide Approach Focus on improving air pollution by reducing total
citywide emissions over the long-term and assuring that localized air pollution exposures conform to
adopted health standards.
2014 Legislative Policy Agenda:
The City’s Air Quality Plan establishes a strong overall goal to “continually improve Fort Collins air
quality.”
1. Support legislation and regulations adopting programs and policies that improve public health and
air quality.
2. Support legislation that maintains or increases the stringency of air quality standards.
4. Support legislation that promotes regional improvement of air quality, recognizing that air pollution
does not follow jurisdictional boundaries.
FINANCIAL / ECONOMIC IMPACTS
The Air Quality Advisory Board is a voluntary board. There is no cost associated with their review of the draft
air permit.
The City collaborated with Larimer County to procure services of an air quality professional consultant. The
City’s share of this cost was $3,200.
ENVIRONMENTAL IMPACTS
The comments provided by the City of Fort Collins to CDPHE-APCD on the draft air permit may help to shape the
final air permit and support protection of air quality and public health.
BOARD / COMMISSION RECOMMENDATION
The Air Quality Advisory Board was actively engaged in this issue for over 5 months and developed
recommended comments based on technical analysis, public input, and staff expertise. The comments, to be
submitted to CDPHE-APCD regarding the draft air permit are included in Exhibit A.
PUBLIC OUTREACH
The City of Fort Collins hosted a public listening session with the CDPHE-APCD and the CAAT on
Wednesday, May 14, 2014 to provide an opportunity for citizens to express concerns regarding the asphalt
plant and for officials to present information about the state’s air permitting and public comment process. The
meeting was held in response to Martin Marietta Materials’ application for an air permit for its asphalt plant at
1800 N. Taft Hill Road. Over 75 members of the public were present at this meeting. Copies of presentations,
FAQs, and link to video from this meeting can be found at <http://www.fcgov.com/airquality/>
The Air Quality Advisory Board addressed the asphalt plant issue at its monthly meeting on April 21, 2014.
Members of CAAT, personnel from MMM, and City staff gave presentations on the plant operations, regulatory
process, and potential impacts. Approximately 21 members of the public were present at this meeting. Copies
of presentations can be found at <http://www.fcgov.com/airquality/>
Agenda Item 17
Item # 17 Page 4
The Air Quality Advisory Board hosted a joint meeting with the Larimer County Environmental and Science
Advisory Board on August 18, 2014. A presentation was made by Air Resource Specialists, on the results of
their review of the draft permit, supporting documentation, and modeling analysis (Attachment 3).
ATTACHMENTS
1. Draft Construction Permit_13LR2446 (PDF)
2. MMM_FINAL_Report (REV1) (PDF)
3. March 25, 2014 Letter to Council (PDF)
4. April 17, 2014 Letter to Colorado Department Public Health & Environment (PDF)
5. May 7, 2014 Letter to Council (PDF)
6. Powerpoint Presentation (PPTX)
AIRS ID: 069/0128/005 Page 1 of 12
Version 2009-1
COLORADO DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT
AIR POLLUTION CONTROL DIVISION
TELEPHONE: (303) 692-3150
CONSTRUCTION PERMIT
PERMIT NO: 13LR2446
Issuance 1
DATE ISSUED:
ISSUED TO: Martin Marietta Materials, Inc.
THE SOURCE TO WHICH THIS PERMIT APPLIES IS DESCRIBED AND LOCATED AS FOLLOWS:
Stationary Hot Mix Asphalt plant, and associated materials storage, unloading, loading and
stockpiles facility, located at 1800 North Taft Hill Road, in Larimer County, Colorado.
THE SPECIFIC EQUIPMENT OR ACTIVITY SUBJECT TO THIS PERMIT INCLUDES THE FOLLOWING:
AIRS
Point
Description
Allowable
Fuels
005
One (1) Astec, Model: Turbo 400, Serial Number: 97-010,
Counter flow drum Mix asphalt plant.
One (1) Hauck, model: SJ-4580, Serial Number:
PRN27815 burner design rated at 120 MMBtu per hour.
Particulate matter (PM) emissions are controlled by a
Fabric Filter Baghouse and the associated storage silos.
Silo emissions of PM are controlled by a fabric filter
baghouse.
natural gas
and liquid
petroleum gas
(LPG) for the
drum and
asphalt
heater.
Fugitive emissions of particulate matter resulting from on-
site truck traffic, aggregate stockpiles, and material
handling. Particulate control measures listed at the end
of this permit are used to control fugitive emissions.
THIS PERMIT IS GRANTED SUBJECT TO ALL RULES AND REGULATIONS OF THE COLORADO AIR
QUALITY CONTROL COMMISSION AND THE COLORADO AIR POLLUTION PREVENTION AND
CONTROL ACT C.R.S. (25-7-101 et seq), TO THOSE GENERAL TERMS AND CONDITIONS INCLUDED
IN THIS DOCUMENT AND THE FOLLOWING SPECIFIC TERMS AND CONDITIONS:
REQUIREMENTS TO SELF-CERTIFY FOR FINAL APPROVAL
1. Within one hundred and eighty days (180) after commencement of operation, compliance with the
conditions contained on this permit shall be demonstrated to the Division. It is the permittee's
responsibility to self certify compliance with the conditions. Failure to demonstrate compliance
within 180 days may result in revocation of the permit or enforcement action by the Division.
Information on how to certify compliance was mailed with the permit or can be obtained from the
Division. (Reference: Regulation No. 3, Part B, IlI.G.2).
Colorado Department of Public Health and Environment
Air Pollution Control Division
Martin Marietta Materials, Inc.
Permit No. 13LR2446
Issuance 1
AIRS ID: 069/0128/005 Page 2 of 12
2. Within one hundred and eighty days (180) after commencement of operation, the operator shall
complete all initial compliance testing and sampling as required in this permit and submit the
results to the Division as part of the self-certification process. (Reference: Regulation No. 3, Part
B, III.E.)
3. The owner or operator shall develop an operating and maintenance (O&M) plan, along with a
recordkeeping format, that outlines how the applicant will maintain compliance on an ongoing
basis with the requirements of this permit. Compliance with the O&M plan shall commence at
startup. Within one hundred and eighty days (180) after commencement of operation, the owner
or operator shall submit the O&M plan to the Division. Failure to submit an acceptable operating
and maintenance plan could result in revocation of the permit. (Reference: Regulation No. 3,
Part B, III.E.)
4. Within thirty (30) days after commencement of operation, the permit number shall be marked on
the subject equipment for ease of identification. (Reference: Regulation No. 3, Part B, III.E.)
(State only enforceable)
EMISSION LIMITATIONS AND RECORDS
5. Emissions of air pollutants shall not exceed the following limitations (as calculated using the
emission factors included in the Notes to Permit Holder section of this permit). Monthly and
Annual records of the actual emission rates shall be maintained by the applicant and made
available to the Division for inspection upon request. (Reference: Regulation No. 3, Part B,
Section II.A.4)
Annual Limits:
AIRS
Point
Tons per Year
Emission Type
PM PM10 PM2.5 NOx SO2 VOC CO
005 5.4 1.8 1.3 6.5 0.8 7.6 72.2 Point
005 3.7 0.9 0.1 - - - - Fugitive
See “Notes to Permit Holder #4” for information on emission factors and methods used to
calculate limits.
Compliance with the annual limits shall be determined by recording the facility’s annual emissions
for the pollutants listed above on a rolling twelve (12) month total. By the end of each month a
new twelve-month total shall be calculated based on the previous twelve months’ data. The
permit holder shall calculate monthly emissions and keep a compliance record on site, or at a
local field office with site responsibility, for Division review.
Note: Compliance with the fugitive emission limits shall be demonstrated by not
exceeding the production limits in condition number 9 and by following the
attached particulate emissions control plan.
6. The particulate emission control measures listed on the attached page (as approved by the
Division) shall be applied to the particulate emission producing sources as required by Regulation
No. 1, Section III.D.1.b.
Colorado Department of Public Health and Environment
Air Pollution Control Division
Martin Marietta Materials, Inc.
Permit No. 13LR2446
Issuance 1
AIRS ID: 069/0128/005 Page 3 of 12
7. The following control equipment shall be maintained and operated to ensure satisfactory
performance. The owner or operator shall monitor compliance with this condition through the
results of approved compliance tests (when required), compliance with the Operating and
Maintenance Plan, compliance records, and other methods as approved by the
Division. (Reference: Regulation No. 3, Part B, Section III.E.)
AIRS
Point
Control Device Controlled Pollutants
005 Baghouse PM, PM10, and PM2.5
PROCESS LIMITATIONS AND RECORDS
8. This source shall be limited to the following maximum consumption, processing and/or
operational rates as listed below. Monthly and Annual records of the actual process rate shall be
maintained by the applicant and made available to the Division for inspection upon request.
(Reference: Regulation 3, Part B, II.A.4)
Process/Consumption Limits
AIRS
Point
Process Parameter Annual Limit
005
Total production of asphalt, including
asphalt produced with LPG, shall not
exceed
475,000 tons per year
005
Production of asphalt while heating the
drum with LPG shall not exceed
40,000 tons per year
Compliance with the yearly process limits shall be determined on a rolling twelve (12) month total.
By the end of each month a new twelve-month total is calculated based on the previous twelve
months’ data. The permit holder shall calculate monthly process rate and keep a compliance
record on site or at a local field office with site responsibility, for Division review.
STATE AND FEDERAL REGULATORY REQUIREMENTS
9. Visible emissions shall not exceed twenty percent (20%) opacity during normal operation of the
source. During periods of startup, process modification, or adjustment of control equipment
visible emissions shall not exceed 30% opacity for more than six minutes in any sixty consecutive
minutes. Opacity shall be determined using EPA Method 9. (Reference: Regulation No. 1,
Section II.A.1. & 4.)
10. This source is subject to the odor requirements of Regulation No. 2. (State only enforceable)
11. This source is subject to Regulation No. 6 – Standards of Performance for New Stationary
Sources, Part A – Federal Register Regulations Adopted By Reference, Subpart I - Standards of
Performance for Hot Mix Asphalt Facilities, including, but not limited to, the following:
a. Concentration of particulate matter in the gases discharged into the atmosphere shall not
be in excess of 0.04 grain per dry standard cubic foot.
b. Discharge into the atmosphere shall not exhibit 20 % opacity, or greater.
Colorado Department of Public Health and Environment
Air Pollution Control Division
Martin Marietta Materials, Inc.
Permit No. 13LR2446
Issuance 1
AIRS ID: 069/0128/005 Page 4 of 12
12. The following requirements of Regulation No. 6, Part A, Subpart A, General Provisions, apply.
a. At all times, including periods of start-up, shutdown, and malfunction, the facility and
control equipment shall, to the extent practicable, be maintained and operated in a
manner consistent with good air pollution control practices for minimizing emissions.
Determination of whether or not acceptable operating and maintenance procedures are
being used will be based on information available to the Division, which may include, but
is not limited to, monitoring results, opacity observations, review of operating and
maintenance procedures, and inspection of the source. (Reference: Regulation 6, Part A.
General Provisions from 40CFR60.11
b. No article, machine, equipment or process shall be used to conceal an emission that
would otherwise constitute a violation of an applicable standard. Such concealment
includes, but is not limited to, the use of gaseous diluents to achieve compliance with an
opacity standard or with a standard that is based on the concentration of a pollutant in
the gases discharged to the atmosphere. (§ 60.12)
c. Records of startups, shutdowns, and malfunctions shall be maintained, as required under
§ 60.7.
d. Performance tests shall be conducted as required under § 60.8.
e. Compliance with opacity standards shall be demonstrated according to § 60.11.
A copy of the complete applicable subpart(s) may found at:
http://www.gpoaccess.gov/cfr/retrieve.html
13. This source is located in an ozone non-attainment area, and an attainment-maintenance area for
CO. NOx and VOCs are regulated as precursors to ozone. Therefore this source is subject to the
Reasonably Available Control Technology (RACT) requirements of Regulation Number 3, Part B,
III.D.2 for those pollutants. RACT for this source is determined to be “no additional control”
beyond the good combustion practices incorporated in to the plant design due to excessive cost
per ton of emission removed.
OPERATING & MAINTENANCE REQUIREMENTS
14. The owner or operator shall develop an operating and maintenance (O&M) plan, along with a
recordkeeping format, that outlines how the applicant will maintain compliance on an ongoing
basis with the requirements of this permit. Compliance with the O&M plan shall commence at
startup. Within one hundred and eighty days (180) after commencement of operation, the owner
or operator shall submit the O&M plan to the Division. Failure to submit an acceptable operating
and maintenance plan could result in revocation of the permit. (Reference: Regulation No. 3,
Part B, III.E.)
COMPLIANCE TESTING AND SAMPLING
Initial Testing Requirements
15. The owner or operator shall demonstrate compliance with Condition #11 (NSPS Subpart I), using
EPA Method 9 to measure opacity from the stack. For purposes of determining initial compliance,
the minimum total time of observations shall be 3 hours and the opacity observations shall be
Colorado Department of Public Health and Environment
Air Pollution Control Division
Martin Marietta Materials, Inc.
Permit No. 13LR2446
Issuance 1
AIRS ID: 069/0128/005 Page 5 of 12
conducted concurrently with the initial performance test required in §60.8. (Reference: Regulation
No. 6, Part A, Subpart A, General Provisions § 60.11)
16. A source initial compliance test shall be conducted at the main stack on this plant to demonstrate
compliance with the pollutant emission rates listed below. The test protocol, test and test report
must be in accordance with the requirements of the Air Pollution Control Division Compliance
Test Manual using EPA approved methods. The protocol shall be submitted to the Division for
review and approval at least thirty (30) days prior to testing. No compliance test shall be
conducted without prior approval from the Division. (Reference: Common Provisions II.C and
Regulation No. 3, Part B; III.G.3)
Particulate Matter (PM): 5.133 tons per year
0.04 grains per dscf of exhaust. (NSPS Subpart I)
Carbon Monoxide (CO): 69.113 tons per year
0.291 pounds per ton of asphalt produced
Oxides of Nitrogen (NOx): 6.175 tons per year
0.26 pounds per ton of asphalt produced
ADDITIONAL REQUIREMENTS
17. This permit replaces the following permits and/or points, which are canceled upon issuance of
this permit.
Permit No. AIRS ID Notes
97PO0030 777/1050/001 Permit is being reissued as a stationary permit.
18. The AIRS ID number shall be marked on the subject equipment for ease of identification.
(Reference: Regulation No. 3, Part B, III.E.) (State only enforceable)
19. A revised Air Pollutant Emission Notice (APEN) shall be filed: (Reference: Regulation No. 3, Part
A, II.C)
a. Annually whenever a significant increase in emissions occurs as follows:
For any criteria pollutant:
For sources emitting less than 100 tons per year of a criteria pollutant, a
change in annual actual emissions of five (5) tons per year or more, above the
level reported on the last APEN; or
For volatile organic compounds (VOC) and nitrogen oxides sources (NOx) in
ozone nonattainment areas emitting less than one hundred tons of VOC or
NOx per year, a change in annual actual emissions of one (1) ton per year or
more or five percent, whichever is greater, above the level reported on the last
APEN; or
For sources emitting 100 tons per year or more of a criteria pollutant, a
change in annual actual emissions of five percent or fifty (50) tons per year or
more, whichever is less, above the level reported on the last APEN submitted; or
Colorado Department of Public Health and Environment
Air Pollution Control Division
Martin Marietta Materials, Inc.
Permit No. 13LR2446
Issuance 1
AIRS ID: 069/0128/005 Page 6 of 12
For sources emitting any amount of lead, a change in actual emissions of fifty
(50) pounds of lead above the level reported on the last APEN submitted.
For any non-criteria reportable pollutant:
If the emissions increase by 50% or five (5) tons per year, whichever is less,
above the level reported on the last APEN submitted to the Division.
b. Whenever there is a change in the owner or operator of any facility, process, or
activity; or
c. Whenever new control equipment is installed, or whenever a different type of
control equipment replaces an existing type of control equipment; or
d. Whenever a permit limitation must be modified; or
e. No later than 30 days before the existing APEN expires.
20. Public access shall be precluded in all areas within the modeling receptor exclusion zone (as
seen in attachment A) as submitted with the modeling in the application. The exclusion zone
shall be and posted with no trespassing signs and patrolled during hours of operation.
(Reference: Regulation No. 3, Part B, Section III.B.5
21. The source shall notify the Division if there is a change in the location of the asphalt plant to
determine if a revision to the ambient air quality analysis is necessary.
22. The requirements of Colorado Regulation No. 3, Part D shall apply at such time that any
stationary source or modification becomes a major stationary source or major modification solely
by virtue of a relaxation in any enforceable limitation that was established after August 7, 1980,
on the capacity of the source or modification to otherwise emit a pollutant such as a restriction on
hours of operation (Colorado Regulation No. 3, Part D, Section VI.B.4).
With respect to this Condition, Part D requirements may apply to future modifications if emission
limits are modified to equal or exceed the following threshold levels:
AIRS
Point
Equipment
Description
Pollutant
Emissions - tons per year
Threshold
current
permit limit
005 Asphalt Plant CO 250 72.2
GENERAL TERMS AND CONDITIONS:
23. This permit and any attachments must be retained and made available for inspection upon
request. The permit may be reissued to a new owner by the Division as provided in Regulation
No. 3, Part B, Section II.B upon a request for transfer of ownership and the submittal of a revised
APEN and the required fee.
Colorado Department of Public Health and Environment
Air Pollution Control Division
Martin Marietta Materials, Inc.
Permit No. 13LR2446
Issuance 1
AIRS ID: 069/0128/005 Page 7 of 12
24. If this permit specifically states that final approval has been granted, then the remainder of this
condition is not applicable. Otherwise, the issuance of this construction permit is considered initial
approval and does not provide "final" approval for this activity or operation of this source. Final
approval of the permit must be secured from the APCD in writing in accordance with the
provisions of 25-7-114.5(12)(a) C.R.S. and AQCC Regulation No. 3, Part B, Section III.G. Final
approval cannot be granted until the operation or activity commences and has been verified by
the APCD as conforming in all respects with the conditions of the permit. Once self-certification
of all points has been reviewed and approved by the Division, it will provide written
documentation of such final approval. Details for obtaining final approval to operate are
located in the Requirements to Self-Certify for Final Approval section of this permit. The
operator shall retain the permit final approval letter issued by the Division after completion of self-
certification with the most current construction permit.
25. This permit is issued in reliance upon the accuracy and completeness of information supplied by
the applicant and is conditioned upon conduct of the activity, or construction, installation and
operation of the source, in accordance with this information and with representations made by the
applicant or applicant's agents. It is valid only for the equipment and operations or activity
specifically identified on the permit.
By:
By:
K.C. Houlden R K Hancock III, P.E.
Permit Engineer Construction Permits Unit Supervisor
Permit History
Issuance Date Description
Initial Approval This Issuance Issued to Martin Marietta Materials. Conversion from
portable permit # 97PO0030.
Notes to permit holder:
1) The production or raw material processing limits and emission limits contained in this permit are
based on the production/processing rates requested in the permit application. These limits may
be revised upon request of the permittee providing there is no exceedence of any specific
emission control regulation or any ambient air quality standard. A revised air pollutant emission
notice (APEN) and application form must be submitted with a request for a permit revision.
2) This source is subject to the Common Provisions Regulation Part II, Subpart E, Affirmative
Defense Provision for Excess Emissions During Malfunctions. The permittee shall notify the
Division of any malfunction condition which causes a violation of any emission limit or limits
stated in this permit as soon as possible, but no later than noon of the next working day, followed
by written notice to the Division addressing all of the criteria set forth in Part II.E.1. of the
Common Provisions Regulation. See:
http://www.cdphe.state.co.us/regulations/airregs/5CCR1001-2.pdf.
3) In accordance with C.R.S. 25-7-114.1, each Air Pollutant Emission Notice (APEN) associated
Colorado Department of Public Health and Environment
Air Pollution Control Division
Martin Marietta Materials, Inc.
Permit No. 13LR2446
Issuance 1
AIRS ID: 069/0128/005 Page 8 of 12
with this permit is valid for a term of five years from the date it was received by the Division. A
revised APEN shall be submitted no later than 30 days before the five-year term expires. Please
refer to the most recent annual fee invoice to determine the APEN expiration date for each
emissions point associated with this permit. For any questions regarding a specific expiration date
call the Division at (303)-692-3150.
4) The following emissions of non-criteria reportable air pollutants are estimated based upon the
process limits as indicated in this permit. This information is listed to inform the operator of the
Division's analysis of the specific compounds emitted if the source(s) operate at the permitted
limitations.
AIRS
Point Pollutant CAS #
Uncontrolled
Emission Rate
(lb/yr)
Are the
emissions
reportable?
Controlled
Emission
Rate (lb/yr)
005
Acetaldehyde 75070 618 YES 618
Formaldehyde 50000 1,473 YES 1,473
Toluene 108883 1,378 YES 1,378
Benzene 71432 185 NO 185
Ethylbenzene 100414 114 NO 114
Quinone 106514 76 NO 76
Hydrochloric Acid
(HCL)
1330207 95 NO 95
5) The emission levels contained in this permit are based on the following emission factors:
Point 005 Drum Mixer when operating on Natural Gas:
Emission Factors - Uncontrolled Emission Factors – Controlled
Pollutant lb/ton of
asphalt
Source lb/ton of
asphalt
Source
PM 27.916 Division Derived 0.02162 Division Derived
PM10 8.3748 Division Derived 0.00649 Division Derived
PM2.5 2.3476 Division Derived 0.00454 Division Derived
NOx 0.0260 AP-42 0.0260 AP-42
CO 0.2910 Applicant 0.2910 Applicant
VOC 0.0320 AP-42 0.0320 AP-42
SO2 0.0034 AP-42 0.0034 AP-42
Point 005 Drum Mixer when operating on Liquid Petroleum Gas (LPG):
Emission Factors - Uncontrolled Emission Factors – Controlled
Pollutant lb/ton of
asphalt
Source lb/ton of
asphalt
Source
PM 27.916 Division Derived 0.02162 Division Derived
PM10 8.3748 Division Derived 0.00649 Division Derived
Colorado Department of Public Health and Environment
Air Pollution Control Division
Martin Marietta Materials, Inc.
Permit No. 13LR2446
Issuance 1
AIRS ID: 069/0128/005 Page 9 of 12
Emission Factors - Uncontrolled Emission Factors – Controlled
Pollutant lb/ton of
asphalt
Source lb/ton of
asphalt
Source
SO2 0.0034 AP-42 0.0034 AP-42
Point 005 Asphalt Heater when operating on Natural Gas and Liquid Petroleum Gas (LPG):
Emission Factors -
Uncontrolled
Emission Factors –
Controlled
Pollutant lb/MMcf Nat. Gas Source lb/MMcf Nat. Gas Source
PM 7.60 AP-42 7.60 AP-42
PM10 7.60 AP-42 7.60 AP-42
PM2.5 7.60 AP-42 7.60 AP-42
NOx 100.00 AP-42 100.00 AP-42
CO 84.00 AP-42 84.00 AP-42
VOC 5.50 AP-42 5.50 AP-42
SO2 0.60 AP-42 0.60 AP-42
Materials Hauling and Stockpile (Fugitive):
Particulate Matter (TSP): .......................... 0.0005 pounds per ton of HMA produced
Particulate Matter < 10 µm (PM10): ……..0.0005 pounds per ton of HMA produced
Particulate Matter < 2.5 µm (PM2.5):…….0.0003 pounds per ton of HMA produced
Silo Operations:
Particulate Matter (TSP): .......................... 0.0006 pounds per ton of HMA produced
Particulate Matter < 10 µm (PM10): ……..0.0006 pounds per ton of HMA produced
Particulate Matter < 2.5 µm (PM2.5):…….0.0003 pounds per ton of HMA produced
Colorado Department of Public Health and Environment
Air Pollution Control Division
Martin Marietta Materials, Inc.
Permit No. 13LR2446
Issuance 1
AIRS ID: 069/0128/005 Page 10 of 12
6) This facility is classified as follows:
Applicable
Requirement
Status
Operating Permit Synthetic Minor facility for CO,
PSD Synthetic Minor facility for CO
NANSR Minor facility
7) Full text of the Title 40, Protection of Environment Electronic Code of Federal Regulations can be
found at the website listed below:
http://ecfr.gpoaccess.gov/
Part 60: Standards of Performance for New Stationary Sources
NSPS 60.90-60.93 Subpart I
8) The permit holder is required to pay fees for the processing time for this permit. An invoice for
these fees will be issued after the permit is issued. The permit holder shall pay the invoice within
30 days of receipt of the invoice. Failure to pay the invoice will result in revocation of this permit
(Reference: Regulation No. 3, Part A, Section VI.B.)
9) Unless specifically stated otherwise, the general and specific conditions contained in this permit
have been determined by the Division to be necessary to assure compliance with the provisions
of Section 25-7-114.5(7)(a), C.R.S.
10) Each and every condition of this permit is a material part hereof and is not severable. Any
challenge to or appeal of a condition hereof shall constitute a rejection of the entire permit and
upon such occurrence, this permit shall be deemed denied ab initio. This permit may be revoked
at any time prior to self-certification and final authorization by the Division on grounds set forth in
the Colorado Air Pollution Prevention and Control Act and regulations of the AQCC including
failure to meet any express term or condition of the permit. If the Division denies a permit,
conditions imposed upon a permit are contested by the applicant, or the Division revokes a
permit, the applicant or owner or operator of a source may request a hearing before the AQCC for
review of the Division’s action.
11) Section 25-7-114.7(2)(a), C.R.S. requires that all sources required to file an Air Pollutant
Emission Notice (APEN) must pay an annual fee to cover the costs of inspections and
administration. If a source or activity is to be discontinued, the owner must notify the Division in
writing requesting a cancellation of the permit. Upon notification, annual fee billing will terminate.
12) Violation of the terms of a permit or of the provisions of the Colorado Air Pollution Prevention and
Control Act or the regulations of the AQCC may result in administrative, civil or criminal
enforcement actions under Sections 25-7-115 (enforcement), -121 (injunctions), -122 (civil
penalties), -122.1 (criminal penalties), C.R.S.
Colorado Department of Public Health and Environment
Air Pollution Control Division
Martin Marietta Materials, Inc.
Permit No. 13LR2446
Issuance 1
AIRS ID: 069/0128/005 Page 11 of 12
PARTICULATE EMISSIONS CONTROL PLAN FOR MATERIAL PROCESSING ACTIVITIES
THE FOLLOWING PARTICULATE EMISSIONS CONTROL MEASURES SHALL BE USED FOR
COMPLIANCE PURPOSES ON THE ACTIVITIES COVERED BY THIS PERMIT, AS REQUIRED BY
THE AIR QUALITY CONTROL COMMISSION REGULATION NO.1, Section III.D.1.b. THIS SOURCE IS
SUBJECT TO THE FOLLOWING EMISSION GUIDELINES:
a. Processing Activities - Visible emissions not to exceed 20%, no off-property transport of visible
emissions.
b. Haul Roads - No off-property transport of visible emissions shall apply to on-site haul roads, the
nuisance guidelines shall apply to off-site haul roads.
c. Haul Trucks - There shall be no off-property transport of visible emissions from hauls trucks
when operating on the property of the owner or operator. There shall be no off-vehicle transport
of visible emissions from the material in the haul trucks when operating off of the property of the
owner or operator.
CONTROL MEASURES
1. Material stockpiles shall be watered as necessary to control fugitive particulate emissions. Aggregate
materials shall be sprayed with water during material loading into the storage bins or stockpiles if
necessary.
2. On site haul roads used to move aggregate shall be graveled. Watering shall be implemented if dust
problems occur.
3. On site haul roads for removal of hot mix asphalt from site shall be paved and or graveled. Watering
shall be implemented if dust problems occur.
4. Vehicle speed on haul roads and service roads shall be restricted to 15 miles per hour. Speed limit
signs shall be posted.
Colorado Department of Public Health and Environment
Air Pollution Control Division
Martin Marietta Materials, Inc.
Permit No. 13LR2446
Issuance 1
AIRS ID: 069/0128/005 Page 12 of 12
Attachment A
Figure: map/aerial image identifying stack and radius.
2014 MARTIN MARIETTA MATERIALS
FINAL TECHNICAL REPORT
REVIEW OF DRAFT
AIR QUALITY PERMIT 13LR2446
Prepared for:
LARIMER COUNTY
AND
CITY OF FORT COLLINS
Prepared by:
D. HOWARD GEBHART
Air Resource Specialists, Inc.
1901 Sharp Point Drive, Suite E
Fort Collins, Colorado 80525
Telephone: 970-484-7941
Fax: 970-484-3423
August 2014
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
TABLE OF CONTENTS
Section Page
1.0 Introduction 1-1
1.1 Background 1-1
1.2 Overview of Martin Marietta Asphalt Plant Site 1-1
1.3 Site Characteristics 1-3
2.0 Review of Emission Estimates 2-1
2.1 Criteria Air Pollutants 2-1
2.2 Hazardous Air Pollutants 2-2
3.0 Review of Dispersion Modeling 3-1
3.1 APCD Modeling Studies 3-1
3.2 Additional HAP Modeling Analysis 3-4
4.0 Reasonably Available Control Technology 4-1
4.1 RACT for VOC Emissions 4-1
4.2 RACT for CO Emissions 4-2
5.0 Technical Comments on Draft Permit 5-1
6.0 Summary & Conclusion 6-1
LIST OF FIGURES
Figure Page
1-1 Martin Marietta Materials Google Earth Image 1-2
1-2 MMM Asphalt Batch Plant 1-3
4-1 Image of Recycle Air Collection Point at MMM Asphalt Plant 4-2
LIST OF TABLES
Table Page
2-1 MMM Emissions (ton/year) 2-1
2-2 MMM Emissions (lbs/year) 2-2
3-1 1-Hour Averages CO Impact 3-2
3-2 8-Hour Average CO Impacts 3-2
3-3 Location of Public Receptors near MMM 3-5
3-4 MMM HAP Modeling Results – Acute Impacts 3-6
3-5 MMM HAP Modeling Results – Chronic Impacts 3-7
3-6 Background HAP Levels – Fort Collins, Colorado 3-8
4-1 RBLC Query Results: Asphalt Concrete Manufacturing 4-3
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
1.0 INTRODUCTION
1.1 Background
Martin Marietta Materials (MMM) operates a hot mix asphalt plant at 1800 North Taft
Hill Road, located within Larimer County, Colorado (County) and just outside the limits for the
City of Fort Collins (City). The County and City have requested the services of a qualified
environmental consultant to review the draft MMM air quality permit issued for public notice by
the Colorado Air Pollution Control Division (APCD) and provide input to the County’s
Environmental and Science Advisory Board (ESAB) and the City’s Air Quality Advisory Board
(AQAB). The ESAB and AQAB will be responsible for considering the draft permit and
providing any recommendations for submitting official comments on the draft permit by either
the County or City.
Air Resource Specialists, Inc. (ARS) has been selected by the County and City to assist in
the MMM draft permit review. ARS has been assigned the following work, which is documented
in this technical report.
Review Draft Air Permit and Permit Conditions
Review Air Emissions Inventory that supports the MMM Draft Permit
Review Air Dispersion Modeling that supports the MMM Draft Permit
Assess Potential Public Health Impacts of Hazardous Air Pollutant (HAP)
Emissions
Summarize Findings in a Technical Report
Present Findings to a Meeting(s) of the EASB and AQAB
In essence, this study is a “review of the review” conducted by APCD. The study
objectives are to confirm that APCD’s technical analysis supporting the permit decision is based
on sound science and standard regulatory practice. Also, ARS’ review is designed to ensure that
the issued permit is protective of public health and the environment.
The technical review work by Air Resource Specialists, Inc. (ARS) is described in this
report and has been jointly funded by the County and City. A single report has been prepared that
documents the results of the ARS studies.
1.2 Overview of MMM Asphalt Plant Site
According to MMM, mining and processing for aggregate materials has been conducted
at the North Taft Hill Road site since the 1950s. MMM acquired the asphalt plant site in 2011.
The current asphalt plant was relocated to the site under the authority of a “portable source”
permit. Under Colorado Air Pollution Control Commission Regulation #3, an emissions unit can
remain at a single site for only 18 months under a “portable source” permit. MMM wishes to
permanently locate the asphalt plant at the present site and as such, has requested a “stationary
source” permit pursuant to Regulation #3 from the APCD.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
The MMM asphalt plant site is located at 1800 North Taft Hill Road, Fort Collins, CO.
On the west side of Taft Hill Road, MMM operates additional aggregate mining and processing
operations. An image of the asphalt plant site from Google Earth is shown as Figure 1-1.
Figure 1-1. Martin Marietta Materials Google Earth Image.
*Indicates the MMM Asphalt Location
According to materials provided by MMM, the plant produces “warm mix” asphalt,
which is a combination of liquid asphalt cement, aggregate, sand, asphalt binder, and recycled
asphalt pavement (RAP). Based on claims by MMM, a “warm mix” plant operates at
temperatures of less than 300 degrees F, which is 30-70 degrees F cooler than a more
conventional “hot mix” plant. The “warm mix” plant consumes about 20% less fuel.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
Figure 1-2 shows a typical asphalt batch plant.
Figure 1-2. Asphalt Batch Plant (provided by MMM).
At the Taft Hill Road asphalt plant, the air emissions are routed through a fabric filter
emissions control system, also known as a baghouse, before existing through a stack located at
the edge of the baghouse. The fabric filter dust collector is primarily a control device for removal
of particulate matter (PM) emissions and is required to meet the emissions limitations in the
applicable New Source Performance Standards (NSPS) at 40 CFR 60 Subpart I. During a visit to
the facility, ARS confirmed that the baghouse is present to control emissions and appears to be
working effectively based on the lack of visible emissions in the stack exhaust. ARS staff also
observed additional pollution abatement measures not listed in the draft MMM permit. First,
there is a collection point along the product conveyor leading to the asphalt storage silos that
routes volatile organic compound (VOC) emissions lost through the conveyor back to the asphalt
plant burner for destruction. Also, MMM has installed condensers to collect VOC emissions lost
at the liquid asphalt storage tanks. Some of the collected VOC may also be regulated as
hazardous air pollutants (HAPs).
1.3 Site Characteristics
The immediate MMM plant site is rural in character, with some residential housing to the
south. The City of Fort Collins Poudre River Trail also abuts the MMM property on the south
side, with a parking lot for trail access along Taft Hill Road to the immediate south of the MMM
property. The Lincoln Middle School (operated by the Poudre School District) lies about
1 kilometer (km) southeast of the MMM plant site.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
2.0 REVIEW OF EMISSION ESTIMATES
2.1 Criteria Air Pollutants
Table 2-1 summarizes the emissions data for the main stack at the MMM asphalt plant, as
determined by the APCD and summarized in the draft permit.
Table 2-1
MMM Emissions (ton/year)
PM PM10 PM2.5 NOX SO2 VOC CO
Stack 5.4 1.8 1.3 6.5 0.8 7.6 72.2
Fugitive 3.7 0.9 0.1
Total 9.1 2.7 1.4
ARS confirmed that MMM emissions listed above were determined using the maximum
production rate in the permit of 475,000 tons/yr.
For NOX, VOCs, and SO
2, the emissions were calculated using the AP-42 emission
factors for drum mix hot mix asphalt plants fired on natural gas. These emission factors and the
AP-42 citation are listed below:
NOX: 0.026 lb/ton, AP-42, Table 11.1-7
SO2: 0.0034 lb/ton, AP-42, Table 11.1-7
VOC: 0.032 lb/ton, AP-42, Table 11.1-8
For CO emissions, the AP-42 factor is 0.13 lb/ton, but MMM has requested
CO emissions equal to 0.291 lb/ton when combusting natural gas and 0.40 lb/ton when
combusting liquefied petroleum gas (LPG or propane). The reason for the higher CO emissions
at the MMM asphalt plant were not documented in the materials released to the public which
accompanied the draft permit. In response to ARS questions, APCD’s explanation for this
discrepancy is a claim that historical experience shows that the AP-42 CO factor is too low based
on emissions testing at other asphalt plants. For additional discussion of the CO emissions,
please refer to Section 4, Reasonably Available Control Technology.
The PM emissions were calculated by APCD and differ somewhat from the AP-42
values. AP-42 lists uncontrolled emission factors for PM and PM10 of 28 lb/ton and 6.5 lb/ton
respectively (See AP-42, Table 11.1-3). The Division’s PM factor is close to AP-42
(27.916 vs. 28 lb/ton) and the Division’s PM10 factor exceeds the AP-42 value by a small amount
(8.3748 lb/ton vs. 6.5 lb/ton).
PM2.5 is not directly tabulated in AP-42, but AP-42 Table 11.1-4 lists the particle size
distributions from asphalt plant drum mix dryers, and gives a PM2.5 fraction of 5.5% for the
uncontrolled emissions. When these data are applied to the AP-42 uncontrolled PM factor
(28 lb/ton), the derived PM2.5 factor is 1.54 lb/ton. APCD calculated 2.3476 lb/ton for the draft
permit.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
The technical basis for the Division’s emission calculations for PM, PM10, and PM
2.5
were not provided in the materials released to the public which accompanied the draft permit.
However, subsequent correspondence with APCD staff indicates that the Division’s PM
estimates were based on the grain loading from the applicable New Source Performance
Standard (NSPS) which is 0.04 gr/dscf. This is a reasonable approach as the PM emissions are
then consistent with the proposed permit limit.
2.2 Hazardous Air Pollutants (HAPs)
Table 2-2 summarizes the HAP emissions calculated by APCD for the MMM facility.
Please note that HAP emissions are reported in pounds whereas the other pollutant emissions are
listed in tons. All HAPs documented in the APCD materials are released at the asphalt plant
baghouse stack.
Table 2-2
MMM Emissions (lbs/year)
Acetaldehyde Formaldehyde Toluene Benzene Ethylbenzene Quinone HCl
618 1,473 1,378 185 114 76 95
ARS confirmed that the MMM HAP emissions listed above were determined using the
maximum production rate in the permit of 475,000 tons/yr.
HAP emissions listed for benzene, ethylbenzene, and formaldehyde match the AP-42
data for emissions from a natural gas-fired drum mix asphalt plant (AP-42, Table 11.1-10).
These factors are as follows: benzene (0.0039 lb/ton), ethylbenzene (0.00024 lb/ton), and
formaldehyde (0.0031 lb/ton). The APCD toluene factor (derived from the APCD’s emissions
estimate) is 0.0029 lb/ton, compared to the AP-42 factor of 0.00015 lb/ton. The toluene factor
used by APCD is the AP-42 factor for an asphalt plant fired on #2 fuel oil, so it appears that
APCD may have used this factor by mistake instead of the natural gas factor. After correcting for
this error, the toluene emissions would be reduced from 1,378 lb/yr to 71 lb/yr.
In the draft permit, APCD also listed HAP emissions for acetaldehyde, quinone, and
hydrochloric acid (HCl); however, these emissions are not included within the published AP-42
emissions data. In later correspondence with ARS, APCD acknowledged that the data were listed
in error and the expectation is that the estimates for these particular HAP pollutants will be
dropped when the final permit is released.
There are also other HAPs listed in the AP-42 data (AP-42, Table 11.1-10) that have
emissions comparable to the HAPs where emissions were calculated by APCD. These HAPs are
hexane (0.00092 lb/ton), xylene (0.00020 lb/ton), and polycyclic aromatic hydrocarbons or
PAHs (0.00019 lb/ton). The most prevalent PAHs based on AP-42 data are naphthalene and
2-methylnaphthalene. It is unknown why these HAPs were not considered given that the
emissions are comparable to other HAPs where emissions were tabulated by APCD. At the
maximum permitted production rate of 475,000 tons per year, the resulting emissions would be:
hexane 437 lb/yr, xylene 95 lb/yr, and PAHs 90 lb/yr.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
3.0 REVIEW OF DISPERSION MODELING
3.1 APCD Modeling Studies
APCD conducted air quality dispersion modeling for CO emissions using the
US Environmental Protection Agency (US EPA) AERSCREEN model (Version 11126).
AERSCREEN is a simple “screening” model tool that predicts the worst-case concentration
expected from a single emission source over a wide range of possible meteorological dispersion
conditions.
Based on ARS’ review of the modeling documents provided by APCD, it has been
determined that the modeling was done correctly and followed the applicable regulatory
guidelines governing air quality dispersion modeling (40 CFR 51 Appendix W). If anything, for
reasons explained below, the modeling results are likely to be a significant overestimate of the
actual CO impacts which might be realistically expected for the MMM asphalt plant. These
conservatisms are especially pronounced for the 8-hour CO concentration modeling.
For the APCD modeling, the CO emission rate was set to 160 lb/hr, which equals the
expected CO emission rate at the maximum capacity of the asphalt plant (400 ton per hour) when
operating on LPG (emissions of 0.4 lb/ton). AERSCREEN returns the worst-case expected
concentration for an averaging time of 1-hour by calculating the expected concentrations from
the emission source under a wide array of different meteorological dispersion conditions. The
1-hour concentration predicted by AERSCREEN is then adjusted to other averaging times using
an EPA-recommended scaling factor. The 1-hour average AERSCREEN result was converted to
an 8-hour average by APCD for comparison with the 8-hour National Ambient Air Quality
Standard (NAAQS) using a scaling factor of 0.9.
The AERSCREEN modeling result is also added to a “background” concentration, which
accounts for ambient concentrations attributable any regional pollutant sources not explicitly
included in the modeling. APCD reports that it used ambient monitoring data collected over the
period 2004-2006 at the Fort Collins monitor located near the Colorado State University (CSU)
campus to determine the “background”. This is the only ambient CO monitor in the Fort Collins
region. APCD’s analysis states that using background data from the Fort Collins monitor likely
overstates the real background values at the MMM site and ARS concurs with that assessment.
The assumed background level accounts for about 1/3
rd
of the total ambient CO impact in
APCD’s modeling analysis.
AERSCREEN also parameterizes “building downwash”, which describes how the airflow
around nearby buildings and structures within the plant affect atmospheric dispersion and the
resulting pollutant concentrations. There are three (3) structures at MMM that were considered
by APCD for these effects: 1) the lime silo adjacent to the baghouse stack, 2) the product silos
south of the baghouse stack, and 3) the baghouse structure itself. Since AERSCREEN is limited
to addressing only a single building in any given model run, APCD executed the model
separately for each of the three building configurations and then selected the worst-case result
from these model runs. The AERSCREEN output showed that the building configuration with
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
the lime silo caused the highest ambient concentrations and was therefore used by APCD for the
CO modeling results.
AERSCREEN was set such that the minimum source-to-receptor distance modeled was
87 meters, which is the distance from the asphalt plant baghouse stack to the closest property
boundary along Taft Hill Road which borders the facility of the west side. ARS confirmed that
the 87 meter distance matches the distance from the MMM baghouse stack to the closest
property boundary.
AERSCREEN was modeled by APCD using a unit emission rate (1.0 grams per second).
The modeling results were then adjusted to the actual emission rate (160 lb/hr or 20.18 g/sec) by
multiplying the AERSCREEN model output by the emission rate in grams per second. This
methodology accounts for the known relationship in the model that concentrations are linearly
proportional to the emissions rate. The model results are compared to the National Ambient Air
Quality Standards (NAAQS). The CO NAAQS are:
1 – Hour: 35 ppm (40,000 ug/m
3
)
8 – Hour: 9 ppm (10,000 ug/m
3
)
AERSCREEN modeling results for the three building configurations are listed below in
Tables 3-1 and 3-2 for the 1-hour average and 8-hour average CO concentrations.
Table 3-1
1-Hour Average CO Impacts – Martin Marietta Materials
Micrograms per cubic meter
Building
Configuration
AERSCREEN
Concentration
Background
Concentration
Total
Concentration
NAAQS
Lime Silo 7,203 5,750 12,953 40,000
Product Silo 4,639 5,750 10,389 40,000
Baghouse Building 3,078 5,750 8.828 40,000
Table 3-2
8-Hour Average CO Impacts – Martin Marietta Materials
Micrograms per cubic meter
Building
Configuration
AERSCREEN
Concentration
Background
Concentration
Total
Concentration
NAAQS
Lime Silo 6,483 3,450 9,933 10,000
Product Silo 4,175 3,450 7,625 10,000
Baghouse Building 2,770 3,450 6,220 10,000
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
One can see from the APCD modeling results that the predicted concentration using
AERSCREEN complies with the NAAQS for all building scenarios, although the margin of
compliance is small for the worst-case 8-hour average impacts. However, there is ample
conservatism in the modeling analysis such that there is high confidence that the NAAQS would
not be exceeded. The model conservatisms are detailed below.
First, one can see that the modeling results are strongly dependent on which building
affects the airflow. Predicted AERSCREEN concentrations for the building configurations other
than the lime silo produce much lower concentrations compared to the worst-case result.
Based on ARS’ review of the actual AERSCREEN modeling output files provided by
APCD, the lime silo only affects ambient concentrations when winds are generally in a
north-south direction and there is no building effect on concentrations when winds are in an
east-west orientation. However, the minimum distance to the property line of 87 meters occurs
directly to the west of the baghouse stack, which is a direction where the building effects from
the lime silo would be non-existent. So, the worst-case modeling result reported by APCD
actually occurs for an unrealistic scenario. The AERSCREEN output file indicates that the worst-
case flow vector is 300 degrees, and the distance to the property boundary was calculated to be
about 97 meters for that direction. The AERSCREEN modeling results also show that
concentrations decrease rapidly as the downwind distance increases. For the AERSCREEN
results for 300 degrees at 100 meters, the predicted concentration decreases by about 10 percent,
which drops the 8-hour CO level to less than 9,300 micrograms per cubic meter and provides
additional compliance margin, assuming that all other model inputs are unchanged.
Another important conservatism is that APCD’s modeling is based on the higher
short-term emission rate (160 lb/hr) which occurs only when the asphalt plant is fired on LPG.
Under normal operations when the unit is fired on natural gas, the maximum allowable emissions
would be 0.291 lb/ton or 116.4 lb/hr. LPG is a back-up fuel and limited to no more than40,000
tons per year production under the draft permit (which would equal 100 hours per year of
operation at the maximum 400 tph asphalt production rate). If the natural gas CO emissions rate
were applied instead, the modeling result would be more than 25% lower, and the resulting
8-hour CO concentration would be somewhere near 8,160 micrograms per cubic meter, assuming
that all other model inputs are unchanged.
Additional conservatism is introduced by the 0.9 factor used to estimate the 8-hour
concentration. First, the meteorological conditions must be relatively persistent at the worst-case
dispersion condition for the entire 8-hour period for this factor to provide a realistic modeling
result. Second, the asphalt plant must also operate at or near its maximum operating capacity
(400 tons per hour) and use LPG fuel for the entire 8-hour period. Neither condition is likely to
persist for any consecutive 8-hour period, making the APCD modeling results conservative from
that perspective too.
Lastly, as indicated previously, the assumed background concentration (which accounts
for about 1/3
rd
of the total CO impact for the worst-case condition) is also a conservative
overestimate of the true CO background for the MMM plant site given that the background data
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
comes from monitoring data at an urban site (downtown Fort Collins) with considerably more
vehicular traffic emissions.
In summary, the CO modeling results presented by APCD demonstrate compliance with
the NAAQS, although compliance is by a small margin for the 8-hour average NAAQS.
However, the APCD modeling analysis contains a number of conservative assumptions, all
which must occur simultaneously with the worst-case dispersion condition for the predicted
impacts to be a realistic depiction of the actual CO impacts. Given that it is unlikely that all of
the conservative model assumptions would occur simultaneously, there is high confidence based
on the APCD modeling that the NAAQS standards will be achieved in the area surrounding the
MMM asphalt batch plant.
3.2 Additional HAP Modeling Analysis
At the request of Larimer County and the City of Fort Collins, ARS conducted an
assessment of the public health impacts associated with the reported hazardous air pollutant
(HAP) emissions from the MMM asphalt plant. This analysis goes beyond the regulatory
analysis conducted by APCD given that HAP concentrations in the ambient air are not
specifically regulated by the State of Colorado.
The HAP modeling analysis was conducted using the modeling results reported for the
APCD modeling analysis of CO emissions. The results for each HAP of interest were determined
using the APCD unit emissions rate modeling by simply multiplying the APCD AERSCREEN
modeling results by the appropriate emissions data for the HAP pollutant of interest. APCD’s
analysis reports emissions for the following HAPs: acetaldehyde, formaldehyde, toluene,
benzene, ethyl benzene, quinone, and hydrochloric acid. Please note that ARS included
acetaldehyde, quinone, and hydrochloric acid in our analysis despite the understanding that
APCD has since determined these emissions were listed in error. Also, the ARS HAP modeling
is based on the corrected toluene emissions data.
The additional HAP modeling was conducted for specific receptors near MMM where
people were known to live and/or congregate. The locations are as follows:
1) Residence located near the Poudre River Trail parking lot, 2) Residence on Stonecrest Drive
(3
rd
house west from Taft Hill Road, which was determined to be the closest residence along that
street to the MMM asphalt plant emissions stack), and 3) Lincoln Middle School. The UTM
coordinates for each of these locations were determined along with the baghouse stack using
Google Earth and the distance and azimuth of each receptor point relative to the baghouse stack
was calculated using simple geometric relationships. These data are listed below along with the
worst-case AERSCREEN result for that receptor based on the unit emission rate APCD
modeling (1.0 gram per second).
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
Table 3-3
Location of Public receptors near MMM
Distance
(meters)
Azimuth
(degrees from North)
Worst-Case
AERSCREEN
Model Result
(ug/cubic meter)
Residence near Trailhead 239 160.2 232.9
Stonecrest Drive (3rd House) 632 194.3 146.7
Lincoln Middle School (NW Corner of
school building)
1,130 155.6 13.57
As documented previously, the modeling results considered ambient air quality impacts
under three (3) separate scenarios where the influence of nearby buildings and structures were
considered. However, not every building scenario influences pollutant transport in all directions.
For the purpose of this HAP impact analysis, the model results for a given building scenario
were considered only when transport in the direction of the receptor was impacted by that
particular building. Then, the worst-case AERSCREEN model result at the distance of the
receptor of interest was tabulated and using the remaining AERSCREEN data that result was
scaled by the appropriate emissions rate for the HAP pollutant of interest.
The HAP modeling analysis prepared by ARS considered both acute (short-term) and
chronic (long-term) health effects of the pollutant of interest. For the acute effects analysis, ARS
estimated the maximum 1-hour concentration of each HAP and for the chronic effects analysis,
ARS estimated the maximum annual average concentrations for each HAP. The annual
concentration was scaled from the 1-hour AERSCREEN model prediction using the
EPA-recommended factor of 0.1.
The modeling results were compared to “safe” concentration levels determined for each
HAP pollutant and averaging time. The “safe” concentration level was determined from data
reported by USEPA in the document A Preliminary Risk-Based Screening Approach for Air
Toxics Monitoring Data Sets (October 2010), including any subsequent updates to the data tables
from that report. Where multiple concentration thresholds were listed by USEPA’s Risk-Based
Screening Approach, the most conservative threshold, i.e., lowest concentration, was selected
provided that the concentration threshold was for the appropriate averaging time.
For the acute exposures, the lowest concentration threshold in the USEPA Risk-Based
Screening Approach was generally the California “Reference Exposure Level” (REL), which is
defined as the expected concentration level for the pollutant of interest below which no adverse
health effects are anticipated. Most California RELs are derived for an exposure of one hour and
are available online at http://ww.oehha.ca.gov/air/acute_rels/index.html. For ethylbenzene, the
most stringent threshold listed is from the Acute Exposure Guideline Levels (AEGL) developed
by USEPA’s Office of Prevention, Pesticides, and Toxic Substances. The AEGL-1 is the
published threshold for mild health effects. For quinone, the only listed threshold is based on the
Immediately Dangerous to Life & Health (IDLH) concentrations divided by a safety factor of 10.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
The IDLH concentrations were developed by the National Institute for Occupational Safety &
Health (NIOSH).
The acute HAP modeling results are shown below in Table 3-4 for each receptor of
interest.
Table 3-4
MMM HAP Modeling Results – Acute Impacts
Pollutant
Max
Hourly
Emissions
(g/sec)
Calculated
1-Hour Average HAP Exposure
(micrograms/cubic meter)
“Safe”
Concentration
Threshold
(micrograms/cubic
meter)
Receptor:
Residence near
Trailhead:
AERSCREEN
= 232.9 ug/
cubic meter
Receptor:
Stonecrest
Drive (3rd
House):
AERSCREEN
= 146.7 ug/
cubic meter
Receptor:
Lincoln Middle
School:
AERSCREEN
= 13.57 ug/
cubic meter
Acetaldehyde 0.0656 15.3 9.6 0.9 470
Formaldehyde 0.1564 36.4 22.9 2.1 55
Toluene 0.0076 1.8 1.1 0.1 37,000
Benzene 0.0197 4.6 2.9 0.3 1,300
Ethylbenzene 0.0121 2.8 1.8 0.2 140,000
Quinone 0.0081 1.9 1.2 0.1 10,000
Hydrogen
Chloride
0.0101 2.3 1.5 0.1 2,100
For the chronic exposure threshold, a “safe” concentration for HAPs rated as a
carcinogen was determined based on the unit risk factors published by USEPA in the May 21,
2012 update to Table 1 in the Risk-Based Screening Threshold document and assuming an
acceptable excess cancer risk of 1-in-1 million. The potential carcinogens are acetaldehyde,
formaldehyde, benzene, and ethylbenzene. For non-carcinogens, the chronic inhalation threshold
concentration from the USEPA Risk-Based Screening Threshold document was selected. In the
USEPA report, no data are reported for chronic exposures to quinone.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
The chronic HAP modeling results are reported in Table 3-5 below.
Table 3-5
MMM HAP Modeling Results – Chronic Impacts
Pollutant
Max
Hourly
Emissions
(g/sec)
Calculated
Annual Average HAP Exposure
(micrograms/cubic meter)
“Safe”
Concentration
Threshold
(micrograms/cubic
meter)
Receptor:
Residence
near
Trailhead:
AERSCREEN
= 232.9 ug/
cubic meter
Receptor:
Stonecrest
Drive (3rd
House):
AERSCREEN
= 146.7 ug/
cubic meter
Receptor:
Lincoln
Middle
School:
AERSCREEN
= 13.57 ug/
cubic meter
Acetaldehyde* 0.0089 0.207 0.130 0.012 2.2
Formaldehyde* 0.0212 0.494 0.311 0.029 13
Toluene 0.0010 0.024 0.015 0.001 5,000
Benzene* 0.0027 0.062 0.039 0.004 7.80
Ethylbenzene* 0.0016 0.038 0.024 0.002 2.50
Quinone 0.0011 0.025 0.016 0.001 n/a
Hydrogen
Chloride
0.0014 0.032 0.020 0.002 20
*Denotes HAP pollutants that are carcinogens. For these pollutants, the “safe” concentration represents
the threshold for a 1-in-1 million excess cancer risk.
Background concentrations for HAPs were not considered in the above modeling
analysis. Generally, background concentrations for HAPs are low compared to the “safe”
concentration levels; as such, the inclusion of a background level does not significantly alter the
modeling results. Background HAP measurements in Fort Collins were derived from a limited
set of samples collected by APCD in July 2006 at a site near the Colorado State University
Foothills Campus (3414 West Laporte Avenue). Table 3-6 summarizes the limited HAP
measurement data from Fort Collins.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
Table 3-6
Background HAP Levels – Fort Collins, Colorado
Monitoring Data from Three Samples Collected in July 2006
Samples Collected Near Foothills Campus (3414 West Laporte Ave)
Pollutant Sample Concentrations (ppb)
Average MW
(ppb) (ug/m
3
)
Acetaldehyde 2.73 2.41 3.02 2.72 4.89 44
Formaldehyde 3.55 2.94 4.09 3.53 4.32 30
Toluene 0.788 0.685 1.01 0.83 3.11 92
Benzene 0.433 0.395 0.696 0.51 1.62 78
Hexane
As n-hexane
0.276 0.324 0.958 0.52
1.83 86
Xylene
As m-xylene/
p-xylene
0.7 0.634 0.725 0.69 2.97
106
Ethylbenzene 0.226 0.149 0.245 0.21 0.90 106
Based on the analysis presented above, the HAP emissions from the MMM Fort Collins
asphalt plant have been determined to present no significant risk to public health at nearby
receptors frequented by members of the general public.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
4.0 REASONABLY AVAILABLE CONTROL TECHNOLOGY
Because of the MMM location in Fort Collins, emissions control for selected pollutants
must meet the regulatory definition of “reasonably available control technology” or RACT. The
RACT controls are required for nitrogen oxides (NOX) and volatile organic compounds (VOCs),
which are precursors to ozone formation. Fort Collins lies within the Colorado Front Range
ozone “non-attainment area”, meaning that existing concentrations for ozone do not comply with
the National Ambient Air Quality Standards (NAAQS). RACT is also triggered for CO
emissions at MMM. Fort Collins is a CO “maintenance area”, meaning that Fort Collins was
formerly designated as non-attainment for CO, but is currently in attainment with the NAAQS.
The definition of Reasonably Available Control Technology (RACT) is found in the
Colorado Air Quality Control Commission Common Provisions Regulation:
Technology that will achieve the maximum degree of emission control that a
particular source is capable of meeting and that is reasonably available
considering technological and economic feasibility. It may require technology
that has been applied to similar, but not necessarily identical, source categories.
It is not intended that extensive research and development be conducted before a
given control technology can be applied to the source. This does not preclude
requiring a short-term evaluation program to permit the application of a given
technology to a particular type of source.
This report section contains additional information about the proposed MMM controls
and considers whether the proposed emission controls listed in the permit constitute RACT. The
ARS report covers only VOC and CO emissions. NOX emissions were not reviewed because
these emissions are already low (NOX emitted at the MMM asphalt plant only totals 6.5 tons per
year) and as such there would be little perceived environmental benefit associated with improved
NOX emission controls.
4.1 RACT for VOC Emissions
As mentioned previously, MMM has implemented certain voluntary measures aimed at
curbing VOC and HAP emissions which have not been explicitly required in the draft air quality
permit. These measures are:
Collecting exhaust air from the asphalt product conveyer and recycling this air to
the asphalt plant burner for destruction of any associated VOCs and/or HAPs.
Installation of vapor condensers on the liquid asphalt tanks.
Figure 4-1 shows a picture of the recycle air collection point on the MMM asphalt
product conveyor.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
Figure 4-1. Image of Recycle Air Collection Point at MMM Asphalt Plant
Because the above controls have been voluntarily implemented by MMM, it is reasonable
to conclude that these measures are reasonably available considering technological and
economic feasibility, which is the legal definition of RACT under Colorado’s air quality
regulations. The MMM draft air quality permit should be revised to legally require the
installation and operation of MMM’s voluntary VOC/HAP pollution control measures as RACT.
4.2 RACT for CO Emissions
The draft MMM air permit has established CO emission limits equal to 0.291 lb/ton when
the asphalt plant is fired on natural gas and 0.40 lb/ton when the asphalt plant is fired on back-up
LPG fuel. As noted above, the AP-42 CO factor for natural gas-fired drum mix asphalt plants is
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
0.13 lb/ton. APCD staff stated to ARS that they believe that the CO AP-42 emissions are not
technically achievable and as such, the proposed CO emissions (0.291 lb/ton and 0.40 lb/ton) are
RACT because additional emission controls are not cost-effective. However, the MMM permit
and APCD’s supporting technical information provided to the public do not provide any
substantive support for this RACT claim. Based on the permit record, there is no evidence that
APCD in fact evaluated the technical feasibility and cost of any alternative emission controls for
the CO RACT analysis.
The fact that AP-42 data present significantly lower CO emissions (0.13 lb/ton) suggests
that better CO control is indeed technically achievable and likely has been achieved in practice at
other asphalt plants. Given this finding, a technical and economic review of improved CO
controls should have been performed for the MMM draft permit. Without such an analysis, the
CO RACT analysis is deficient.
At the request of the AQAB and ESAB, ARS conducted a review of other asphalt plant
permits to determine if lower CO emissions are in fact technically achievable. ARS conducted a
query using the USEPA RACT/BACT/LAER Clearinghouse (RBLC) that turned up emissions
data for two asphalt plants located in Clark County, Nevada (Las Vegas). These data are
summarized in Table 4-1. It should be noted that both asphalt plants listed in the RBLC were
subject to “best available control technology” (BACT) as the applicable emissions standard and
not RACT. However, the selection of lower CO emissions to meet BACT requirements
documents the technical feasibility of improved CO emissions control and as such, mandates that
such controls be considered as RACT.
Table 4-1
RBLC Query Results: Asphalt Concrete Manufacturing
Source ID RBLC ID CO Permit Limit (BACT)
Nellis Air Force Base NV-0047 0.13 lb/ton, 16.25 lb/hr
Aggregate Industries – Sloan Quarry NV-0045 0.10 lb/ton, 45.0 lb/hr
ARS also located four recent USEPA permits for asphalt plants located on tribal lands in
the western United States. These permits are:
Pioneer Asphalt, Inc. – Permit R10NT502400 (Draft)
Granite Construction Company – Permit R10NT502300 (9/19/2012)
Knife River, Inc. – Permit R10NT502200 (9/19/2012)
Mickelsen Construction, Inc. – Permit R10NT502501 (Draft)
For all of the USEPA permits listed above, the CO emissions control was not subject to
RACT, BACT, or any other emissions standard. Nevertheless, all permits were issued based on
CO emissions at 0.13 lb/ton, which equals the AP-42 emissions value for a natural gas-fired
drum mix asphalt plant. However, none of the USEPA permits appear to have required emissions
testing for CO, so it is unknown if the 0.13 lb/ton emissions level was actually achieved in
practice at any of these facilities.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
In summary, for those cases where asphalt plant emissions control data are posted in the
RBLC and in other asphalt plant permits issued by USEPA Region X, the CO emissions are
significantly lower than the RACT limit established by APCD in the MMM draft permit. The
APCD RACT analysis is deficient without a detailed evaluation of CO emission control options
that might lead to better emissions control and lower allowable CO emissions under the permit.
A review of asphalt plant permits issued elsewhere would suggest that improved CO controls are
technically achievable, so control options to achieve improved CO controls should have been
evaluated by APCD for application as RACT. There is no evidence in the MMM permit record
that such an analysis was conducted.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
5.0 TECHNICAL COMMENTS ON DRAFT PERMIT
This section summarizes possible comments that might be offered by Larimer County
and/or the City of Fort Collins with respect to the proposed Martin Marietta Materials asphalt
plant permit.
HAP Emissions: It appears that the draft permit used the AP-42 toluene factor for drum mix
asphalt plants fired on #2 fuel oil. The AP-42 factors for natural gas drum mix asphalt plants
were used to calculate HAP emissions for other pollutants. This appears to be an oversight and
should be corrected. There are also other HAPs listed in the AP-42 data (AP-42, Table 11.1-10)
that have emissions comparable to the HAPs where emissions were calculated. These HAPs are
hexane (0.00092 lb/ton), xylene (0.00020 lb/ton), and PAHs (0.00019 lb/ton). It is unknown why
these HAPs were not considered by APCD given that the emissions are comparable to other
HAPs where emissions were tabulated.
General Comment: In assessing the asphalt plant, the APCD appears to have considered only the
emissions directly related to the asphalt plant in its analysis. However, MMM owns and operates
other air emission sources in the immediate vicinity of the asphalt plant, including an aggregate
materials mining and processing operation on the west side of Taft Hill Road immediately to the
west of the asphalt plant. Under the Clean Air Act, a “source” is defined as “Any building,
structure, facility, equipment, or installation, or any combination thereof belonging to the same
industrial grouping that emit or may emit any air pollutant subject to regulation under the
Federal Act that is located on one or more contiguous or adjacent properties and that is owned
or operated by the same person or by persons under common control.” MMM’s other aggregate
processing activities located across Taft Hill Road are located on “contiguous or adjacent
properties” and should therefore be considered in the assessment of the overall facility emissions.
ARS’ understanding is that all of the aggregate used in the asphalt plant comes directly from
MMM operations on the west side of Taft Hill Road, so the adjoining operations are “support
facilities” and as such, it cannot be claimed that the asphalt plant is part of a separate source
based on the differences in Standard Industrial Classification (SIC) code. It is probably unlikely
that the added emissions from adjoining MMM operations will alter the minor/major source
classification of the asphalt plant, but a complete and accurate analysis requires that these
emissions also be considered when determining the total emissions of the “source”.
Condition 3, Operating & Maintenance Plan: This permit condition requires that MMM submit
an Operating & Maintenance (O&M) Plan for APCD approval. The plan describes the ongoing
monitoring and recordkeeping activities that MMM will undertake to document compliance with
the terms and conditions of its permit. In essence, any commitments for compliance monitoring
and recordkeeping made by MMM in the O&M Plan will become enforceable requirements of
the permit. While the O&M Plan is not normally subject to review and comment by the public,
due to the sensitivity of emissions to the nearby public in this case, an opportunity for public
input on the O&M Plan could be requested to ensure that the approved O&M Plan provides the
necessary compliance monitoring and recordkeeping to assure permit compliance.
Condition 7, Emissions Control Equipment: This condition lists the pollution control equipment
that MMM must employ to abate pollutant emissions to the atmosphere. However, MMM has
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
voluntarily installed additional equipment to mitigate volatile organic compound (VOC) and
associated hazardous air pollutant (HAP) emissions, including recycling exhaust air from the
asphalt plant outlet conveyor back to the asphalt plant burner along with installing condensers on
the liquid asphalt storage tanks. These voluntary measures adopted by MMM to abate emissions
should be made enforceable legal requirements through the APCD’s air permit. This will assure
that such emissions abatement practices continue going forward. Please also refer to comments
on Condition #10 (Odors) and Condition #13 (RACT).
Condition 10, Odor Control: This is a general requirement referencing Regulation #2 concerning
control and abatement of odors. Given that the MMM asphalt plant has in the past been the
subject of odor complaints, additional requirements for abatement of odors should be considered
for the air quality permit. The voluntary controls that MMM has applied at the asphalt plant
(See Condition 7 above) could be made enforceable requirement on the basis that such controls
are needed to assure compliance with Condition 10 and the associated odor requirements under
Regulation #2.
Condition 13, Reasonably Available Control Technology (RACT) – VOC Emissions: The
Fort Collins region lies within the designated non-attainment area for ozone, and new/modified
emissions of ozone precursors (including VOCs) within the non-attainment area are required
under Regulation #3, Part B, III.E to install reasonably available control technology (RACT) for
emissions control. The APCD has determined that “no additional control” meets RACT.
However, MMM has voluntarily installed additional control for VOC emissions, including
recirculating exhaust air from the asphalt plant product conveyor to the asphalt plant burner and
installing condenser equipment on the liquid asphalt tanks. The mere presence of such equipment
at the MMM Taft Hill Road facility demonstrates the technical feasibility and economic viability
of such emissions controls and therefore mandate that such controls be deemed RACT. As
described under Condition #7, the voluntary VOC emission controls implemented by MMM
should be classified as RACT and required under Permit Condition 13.
Condition 13, Reasonably Available Control Technology (RACT) – CO Emissions: The
Fort Collins region lies within the designated attainment-maintenance area for carbon monoxide
(CO), and new/modified CO emission sources within this area are required under Regulation #3,
Part B, III.E to install reasonably available control technology (RACT) to control emissions. The
APCD has determined that “no additional control” meets RACT. However, it is noted that AP-42
listed emissions for CO at natural gas-fired of 0.13 lb/ton, which is less than 50% of the
0.291 lb/ton limit established at Condition 16 of the draft permit. Permits issued in other
jurisdictions have also set CO permit limits at the AP-42 emissions value (0.13 lb/ton) or lower.
There is no discussion in the permit record as to why lower CO emissions cannot be achieved by
MMM, although APCD has claimed in separate communications with ARS staff that the AP-42
CO emission levels are not achievable. Absent any evidence to the contrary, it would be prudent
for APCD to find that CO emissions at the listed AP-42 value for natural gas-fired drum mix hot
asphalt plants (0.13 lb/ton) represents RACT. Such a limit should be considered for this permit
or APCD should provide the technical basis for its decision and these data should be made
available for review by the public and other interested parties. This comment also affects the
allowable emissions limit for CO contained in Permit Condition 16.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
Condition 14 – O&M Plan: Condition 14 duplicates Condition 3. There is no need to repeat the
O&M Plan requirements in the permit.
Condition 15 – Opacity Testing: This permit condition requires opacity testing to show
compliance with the underlying permit requirements. Since the asphalt plant is approved to
operate on both natural gas and LPG as fuel, the opacity testing should be completed for the
plant on both approved fuels.
Condition 16 – Emissions Testing: This permit condition requires emissions testing to show
compliance with the specified limits for emissions of particulate matter (PM), carbon monoxide
(CO), and oxides of nitrogen (NOx). Since the asphalt plant is approved to operate on both
natural gas and LPG as fuel, the emissions testing should be completed for the plant on both
approved fuels. Also, for clarity, the permit should specify whether or not the particulate testing
is required to include condensable particulate matter (CPM). The hot exhaust from the baghouse
emissions stack suggest that CPM emissions may be present, so the CPM fraction of the PM
emissions needs to be regulated even if not otherwise included in the proposed permit limits.
Condition 16 – Emissions Testing – HAPs: The draft permit as written does not require any
testing for emissions of regulated hazardous air pollutants (HAPs). Generally, without any
authority for regulating HAPs at sources within Colorado, emissions are not tested as there is no
enforceable emissions limit and/or standard for comparison of the testing results. However, HAP
testing could be requested, especially for those HAPs which are known to be carcinogenic
(acetaldehyde, formaldehyde, benzene, etc.). This would provide more reliable data from which
to make a reliable assessment of the possible impact of these emissions on public health.
Condition 21 – Change in Location: It is presumed that the intent of this condition restricts
relocating the asphalt plant within the MMM property. If so, the condition should be clarified
given that a typical hot asphalt plant is known to change locations on a regular basis.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
6.0 SUMMARY & CONCLUSIONS
The major findings of the ARS technical review are summarized below.
The emissions data used for the MMM permit are generally supported by AP-42 and other
appropriate data. However, the CO emissions used by APCD are higher than the
corresponding AP-42 data. APCD claims that historical emissions data do not support the
lower emissions reported by AP-42; however, this claim has not been substantiated by
APCD. Because Fort Collins is a designated maintenance area, CO emissions are required to
meet RACT. AP-42 data along with permits issued to asphalt plants in other jurisdictions
suggest that lower CO emissions are in fact achievable and would represent RACT. APCD
should require lower CO emissions or better document why the selected CO emissions level
is in fact RACT.
MMM has voluntarily adopted emission controls for reduction of VOC and HAP emissions;
specifically, recycling exhaust air from the product conveyor to the asphalt plant burner and
capturing emissions at the liquid asphalt tanks using condensers. The adoption of these
control measures by MMM in fact means that such controls are both technically achievable
and economically viable. Any voluntary controls adopted by MMM would meet the criteria
for RACT and should be legally required under the air quality permit.
The MMM draft permit used the AP-42 toluene emissions factor for drum mix asphalt plants
fired on #2 fuel oil. The AP-42 factors for natural gas drum mix asphalt plants were used to
calculate HAP emissions for other pollutants. This appears to be an oversight by APCD and
should be corrected. Also, other HAPs listed in the AP-42 data (AP-42, Table 11.1-10) where
emissions are comparable to the HAPs calculated by APCD. These HAPs are hexane, xylene,
and PAHs. It is unknown why these HAPs were not considered by APCD given that the
emissions are comparable to other HAPs where emissions were tabulated. APCD’s permit
analysis should be amended to address hexane, xylene, and PAH emissions in addition to the
other HAPs.
In assessing the asphalt plant, the APCD appears to have considered only those emissions
directly related to the asphalt plant. However, MMM owns and operates other air emission
sources in the immediate vicinity of the asphalt plant, including an aggregate materials
mining and processing operation on the west side of Taft Hill Road. MMM’s other aggregate
processing activities are located on “contiguous or adjacent properties” and should therefore
be considered in the assessment of the overall facility emissions. It is unlikely that the added
emissions from adjoining MMM operations will alter the minor/major source classification
of the asphalt plant, but a complete and accurate analysis by APCD requires that these
emissions also be considered when determining the total emissions of the “source”.
Martin Marietta Materials Air Permit Review – Technical Report
Prepared by D. Howard Gebhart
Air Resource Specialists, Inc.
The AERSCREEN modeling for MMM’s CO emissions has been conducted following
standard regulatory practices and principles. This modeling also employed several significant
conservative assumptions. Although the modeling showed that MMM’s emissions comply
with the NAAQS by a small margin, the conservatisms inherent in the modeling study means
that MMM’s operations will comply with the NAAQS, very likely with a substantial safety
margin.
ARS used APCD’s AERMOD modeling results to make an assessment of potential HAP
impacts on public health and the environment. The HAP modeling results from MMM were
compared to “safe” concentration levels determined using USEPA’s Risk-Based Screening
Approach. ARS’ modeling assessment determined that HAP emissions from MMM’s asphalt
plant operations would not cause ambient concentrations above the “safe” concentration
levels determined from USEPA data.
Recommendations have been provided for consideration by the ESAB and AQAB on formal
comments on the draft MMM air quality permit. This includes making any voluntary
pollution control practices adopted by MMM enforceable requirements under the permit.
These recommendations are intended to make the final permit more protective of public
health and the environment.
City Manager’s Office
City Hall
300 LaPorte Ave.
PO Box 580
Fort Collins, CO 80522
970.221.6505
970.224.6107 - fax
fcgov.com
April 17, 2014
Ms. Kirsten King - Program Manager, Stationary Sources
Colorado Department of Public Health & Environment
Air Pollution Control Division
4300 Cherry Creek Drive South
Denver, CO 80222
RE: Martin Marietta Materials – 1800 North Taft Hill Road, Fort Collins, CO
Formal Request for Public Hearing on Draft Air Quality Construction Permit
Dear Ms. King,
Martin Marietta Materials, Inc. has a pending air quality construction permit application before the Air
Pollution Control Division for its hot mix asphalt batch plant, located at 1800 North Taft Hill Road in
Fort Collins. The project site is adjacent to the City of Fort Collins City Limits and within the City’s
Growth Management Area. Lincoln Middle School and two elementary schools, operated by the Poudre
School District, also lie in close proximity to the project site. Approximately 7,000 residents of Fort
Collins and Larimer County live within two miles of the plant. In addition, the City of Fort Collins
maintains a popular recreational trail along the Cache la Poudre River which abuts the subject property on
the south side.
Local citizens have approached public officials in the City of Fort Collins and Larimer County expressing
concerns related to the pending air quality permit application for the Martin Marietta Materials asphalt
plant. Citizens have appeared before the Fort Collins City Council, Larimer County Board of County
Commissioners, and the Board of Education for the Poudre School District to express public health
concerns related to air emissions from the asphalt plant operations. The City of Fort Collins is being
responsive to these concerns within its capacity, however, it does not have jurisdiction regarding the air
quality construction permit for Martin Marietta Materials.
As the regulatory body responsible for issuing an air quality construction permit to Martin Marietta
Materials, it is requested that the Air Pollution Control Division convene a public hearing as part of the
required 30-day public comment and review period for the proposed permit. A hearing will provide the
citizens of Fort Collins and Larimer County an opportunity to appear before the proper regulatory
authority, the Air Pollution Control Division, to express their concerns related to the public health impacts
of this facility and to have these concerns addressed prior to issuance of a final permit.
Sincerely,
Darin Atteberry
City Manager
cc: Mayor Weitkunat
City Councilmembers
Resolution Regarding Comments
on Martin Marietta Materials
Draft Air Permit
City Council Meeting
September 2, 2014
1
Martin Marietta Materials (MMM)
2
• Hot Mix Asphalt Plant
• 1800 Taft Hill Road
• Permitted as “Portable Source”
• Requested ”Stationary Source” permit
through CDPHE – Air Pollution Control
Division (APCD)
APCD Construction Permits
3
• Completes technical and regulatory
review
• Prepares draft permit
• Publishes draft permit
• 30 day comment period
ARS Report – Technical Review
4
• Review Draft Air Permit
• Review Air Emissions Inventory
• Review Air Dispersion Modeling
• Assess Potential Public Health Impacts of
Hazardous Air Pollutant (HAP) Emissions
• Summarize Findings in a Technical Report
Air Quality Advisory Board
5
Considered:
• CDPHE analysis and permit documentation
• ARS Technical Report
• May 14 Public listening session comments
• MMM plant tour
• MMM and Citizen Against Asphalt Toxins
information at April 21 AQAB meeting
Recommended Comments on Permit
6
I. Correct deficiencies and re-submit Draft Permit
for 30 day comment
II. Permit Conditions:
Emissions Controls
• Require existing VOC controls
• Odor detection and controls
• RACT for Carbon Monoxide
(Reasonable Available Control Technology)
Public Review of Ops & Maintenance Plan
Recommended Comments on Permit
(con’t)
7
II. Permit Conditions:
Emissions Testing
• Hazardous Air Pollutants (HAPS) stack test
• Opacity testing, both fuels
• Greater frequency of testing; both fuels
• Clarify which particulate matter elements
to be included
Resolution 2014-080
8
RESOLUTION 2014-080, Adopting the
Recommendations of the Air Quality Advisory Board
Regarding Comments to Colorado Department of
Public Health and Environment on the Draft
Construction Permit 13LR2446 for Martin Marietta
Materials, Inc. Hot Mix Asphalt Plant
- 1 -
RESOLUTION 2014-080
OF THE COUNCIL OF THE CITY OF FORT COLLINS
ADOPTING THE RECOMMENDATIONS OF THE AIR QUALITY ADVISORY BOARD
REGARDING COMMENTS TO COLORADO DEPARTMENT OF PUBLIC HEALTH
AND ENVIRONMENT ON THE DRAFT CONSTRUCTION PERMIT 13LR2446 FOR
MARTIN MARIETTA MATERIALS, INC. HOT MIX ASPHALT PLANT
WHEREAS, the Colorado Department of Public Health and Environment – Air Pollution
Control Division (the “Division”) recently issued a draft Construction Permit No. 13LR2446 on
August 4, 2014, for the Martin Marietta Materials, Inc., hot mix asphalt plant located at 1800
North Taft Hill Road (the “Plant Site”); and
WHEREAS, the Division has determined that this permitting action is subject to a 30-day
public comment period per Colorado Regulation No. 3, Part B, Section III.C., and the public
comment period concludes on September 3, 2014; and
WHEREAS, Martin Marietta Materials, Inc., is converting its existing air permit for a
portable hot mix asphalt plant to a stationary source to be located at the Plant Site for longer than
two years; and
WHEREAS, the Plant Site is located outside and adjacent to the City of Fort Collins city
limits and within the City’s Growth Management Area; and
WHEREAS, local citizens have appeared before the Fort Collins City Council, Larimer
County Board of County Commissioners, and the Board of Education for the Poudre School
District to express public health concerns related to air emissions from the asphalt plant
operations; and
WHEREAS, the City’s Air Quality Advisory Board (the “Board”) has been actively
engaged in reviewing the draft air permit for the Martin Marietta Materials asphalt plant and
pursuant to City Code is tasked with advising the City Council regarding policies, plans, and
programs to improve and maintain the City's air quality; and
WHEREAS, at its regular meeting on August 18, 2014, and subsequent special meeting
on August 25, 2014, the Board recommended comments to the City Council for transmission to
the Division on the draft Construction Permit No. 13LR2446 as set forth in “Exhibit A,” attached
hereto and incorporated herein by this reference; and
WHEREAS, the proposed comments recommended by the Board provide a public benefit
to the Fort Collins community by advocating for the protection of air quality; and
WHEREAS, the City Council wishes to adopt the recommendations of the Board and
cause the transmission of its comments to the Division by September 3, 2014.
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NOW, THEREFORE, BE IT RESOLVED BY THE COUNCIL OF THE CITY OF
FORT COLLINS that the City Council hereby adopts the comments of the Air Quality Advisory
Board as set forth in the attached Exhibit A and directs that this Resolution, including the
comments, be transmitted to the Colorado Department of Public Health and Environment – Air
Pollution Control Division on September 3, 2014.
Passed and adopted at an adjourned meeting of the Council of the City of Fort Collins
this 2nd day of September, A.D. 2014.
_________________________________
Mayor
ATTEST:
_____________________________
City Clerk
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Recommendation to the Fort Collins City Council
from the City Air Quality Advisory Board
regarding Draft Construction Permit issued to Martin Marietta Materials, Inc.
August 25, 2014
We are pleased to offer the following comments regarding Draft Construction Permit number
13LR2446 issued to Martin Marietta Materials Inc (MMM). We reviewed the technical report
analyzing the Draft Permit, prepared by Air Resource Specialists, Inc., for the City of Fort Collins
Environmental Services Department and the Larimer County Department of Health and Environment,
dated August 2014. We used the report to assist the Air Quality Advisory Board in preparing our
comments below.
Our interest lies in the fact that the plant, though not in our city, is immediately adjacent to our city
neighborhoods. Residents of these neighborhoods have well-stated concerns about the effect of
emissions from this facility on their health and safety. Many of these concerns can and should be
better addressed in the permit analyses and permit conditions. Due to the close proximity of many
homes and a school, special care needs to be exercised by the State in issuing permits to construct
equipment, operate the plant, and maintain emissions compliance at this facility. Consequently, we
are requesting that the State air permit(s) to MMM go the extra mile. Using the discretion allowed
within the State Air regulations, the APCD can ensure that the MMM facility is an extra-clean model
Asphalt Batch Plant.
With this in mind, we find the draft permit to be seriously deficient. After correcting these
deficiencies, we request that the State issue a second draft construction permit and restart the 30-day
comment period to allow review of the additional information. The deficient areas are:
Xylene, hexane, and polycyclic aromatic hydrocarbons (PAH) are hazardous air pollutants for
asphalt batch plants that are missing from the analyses. Toluene emissions are incorrectly
calculated. The emission factor (EF) listed in AP-42 for hexane is 0.00092 lb/ton, for PAH
0.00019 lb/ton, and for xylene 0.00020 lb/ton. For toluene emitted from the drum mix asphalt
source, it appears the draft permit used the AP-42 emission factor for #2 fuel oil rather than for
natural gas.
The analysis fails to consider and the draft permit fails to include emissions from the aggregate
materials mining and processing operation immediately west of the asphalt plant. The Clean Air
Act defines a source as “Any building, structure, facility, equipment, or installation, or any
combination thereof belonging to the same industrial grouping that emit or may emit any air
pollutant subject to regulation under the Federal Act that is located on one or more contiguous
or adjacent properties and that is owned or operated by the same person or by persons under
common control.” Thus, all operations from mining through asphalt manufacturing should be
part of one consolidated permit. Though the materials mining and processing operations
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primarily emit particulates, proper control of the emissions as a stipulation of the permit would
also necessarily help reduce fugitive HAPs that have adhered to the particulates. The net result
of such controls will be an overall cleaner facility.
We also find that the draft permit did not include several standard and routine permit conditions that if
implemented can make MMM a model facility. We strongly recommend that the permit explicitly
address each of these additional issues.
Make enforceable all of the control equipment currently operating on the asphalt plant that
reduces ozone precursor emissions. MMM is within the Denver/Northern Front Range ozone
nonattainment area therefore Reasonably Available Control Technology (RACT) should be
required on volatile organic compound (VOC) sources. MMM has installed and is currently
successfully operating control equipment to reduce emissions of VOCs and associated hazardous
air pollutants including recycling exhaust air from the asphalt plant outlet conveyor back to the
asphalt plant burner along with installing condensers on the liquid asphalt storage tanks. The
APCD has determined that “no additional control” meets RACT. But MMM is already using
these technologies so they have to be considered reasonably available and therefore must clearly
constitute RACT. It makes sense then to add these control measures and devices as legally
enforceable conditions in the permit.
Make the process for designing and approving the Operating & Maintenance (O&M) Plan open
and transparent by requiring notification by the State of the public, the City, and other
governmental entities when the plan is submitted to the APCD by MMM, allowing the public to
comment on the proposed details prior to APCD approval, and including the final O&M plan in
the permit. Key to protecting the community affected by this facility is ensuring that the facility
operates within the limits allowed in the permit. Sufficient compliance measures should be
employed to ensure that the control equipment is operating properly and that emission testing is
done as often as is necessary. This includes the ongoing monitoring and recordkeeping that
MMM plans to undertake to document compliance with the terms and conditions of the permit.
Completeness is critical since all commitments for compliance monitoring and recordkeeping
made by MMM in the O&M Plan will become enforceable requirements of the permit.
Make odor detection, control and abatement measures enforceable. This plant has been and is
currently subject to odor complaints. The company has previously responded to these
complaints with specific measures. These measures should be included in the permit as legally
enforceable conditions.
Include as permit conditions all Reasonably Available Control Technology (RACT) and
Reasonably Available Control Measures (RACM) requirements for all sources (point, mobile,
and non-point) for all of the operations from mining through asphalt manufacturing, as part of
the consolidated permit and O&M Plan described above.
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APCD should find that CO emission factors listed in AP-42 for natural gas-fired drum mix hot
asphalt plants, like MMM, constitute RACT. If this were the case, the permitted CO emission
limit for MMM would be lower. MMM lies within a designated attainment-maintenance area
for carbon monoxide (CO), where new/modified CO emission sources are required under
Regulation #3, Part B, III.E to install reasonably available control technology (RACT). The
APCD has determined that for MMM, “no additional control” meets RACT. Yet AP-42 shows a
CO emission factor for a natural gas-fired facility of 0.13 lb/ton. This is less than half the 0.291
lb/ton emission factor established in the draft permit. Unless APCD can defend its decision, the
more stringent emission factor and emission limit should be used.
The permit should require that this specific source be tested to confirm the presence and
emission rate of hazardous air pollutants, especially those known to be carcinogenic. The key
concerns of residents in proximity to this facility are the HAPs. Though we recognize that the
State has limited authority over HAPs and their control, confirming the actual HAPs emissions
from the facility would substantially help inform everyone about the level of threat. HAPs
quantification is required in some other states. For example, in North Carolina, in 1999 the
Division of Air Quality issued an asphalt plant permitting policy, which requires new and
modified asphalt plant applications to quantify all 97 Toxic Air Pollutants (TAPs) emitted to
determine the need for air toxics permit limits using EPA AP-42 emissions. If the emissions of a
specific TAP are below their regulatory threshold in NC Regulation 15A NCAC 2Q.0711, an air
quality permit is not required. If the TAP emissions exceed its threshold, a dispersion modeling
demonstration must be performed. The results of this model must show that the emissions are
below the acceptable ambient level (AAL) listed in NC Regulation 15A NCAC 2D.1104, and air
quality permit emission limit, for the respective TAP not to exceed the AAL, is required. See
http://www.ncair.org/toxics/asphalt/ )
Opacity testing should be conducted using both fuels (natural gas and LPG) approved in the
permit.
Emissions tests should be completed on a regular cycle for the plant on both approved fuels,
natural gas and LPG. For example, in some other states, annual testing of equipment is required.
For example, Arizona’s General Permit for Hot Mix Asphalt Plants requires that, if any
equipment has emission limits specified for any criteria pollutants, the Permittee is required to
conduct performance tests once every year. (See: http://azdeq.gov/calendar/sveugp_hmap.pdf,
page 24.)
The permit should specify whether or not the particulate testing is required to include
condensable particulate matter (CPM). The hot exhaust from the baghouse emissions stack
suggest that CPM emissions may be present, so the CPM fraction of the PM emissions needs to
be regulated even if not otherwise included in the proposed permit limits.
PM2.5 2.3476 Division Derived 0.00454 Division Derived
NOx 0.0260 AP-42 0.0260 AP-42
CO 0.4000 AP-42 0.4000 AP-42
VOC 0.0320 AP-42 0.0320 AP-42