1

MEMORANDUM 

FROM: Lisa Hanle, U.S. EPA, Climate Change Division 

TO: Docket EPA-HQ-OAR-2010-0109, Technical Corrections, Clarifying and 

Other Amendments to Certain Provisions of the Mandatory Greenhouse Gas 

Reporting Rule. 

DATE: May 20, 2010 

SUBJECT: Summary of questions raised on various subparts of the final Mandatory 

Greenhouse Gas Reporting Rule (40 CFR Part 98) after promulgation that are 

being addressed in the proposed technical corrections and other amendments. 

1.0 INTRODUCTION 

On October 30, 2009, EPA published the final rule titled: Mandatory Greenhouse Gas 

Reporting (74 FR 56259), under the authority of Sections 114 and 208 of the Clean Air Act. The 

Mandatory Greenhouse Gas Reporting Rule (MRR) requires reporting of greenhouse gas (GHG) 

emissions and other relevant information from certain sources. The rule requires the monitoring 

of GHGs beginning with the 2010 calendar year, with reports submitted annually by a March 31 

deadline in each following year. The rule does not require control of GHGs, rather it only 

requires that sources above certain threshold levels monitor and report emissions and other 

related data. 

Since promulgation of the rule, the Administrator has identified a number of technical 

issues that need to be corrected and specific portions of the rule that need to be clarified. The 

EPA is proposing to amend specific provisions in the 2009 Final Mandatory Greenhouse Gas 

Reporting rule (2009 Final MRR) to correct certain technical and editorial errors that have been 

identified since promulgation and to proposed clarifying or other amendments to certain 

provisions that have been the subject of questions from reporting entities. 

The purpose of this memorandum is to describe the extent of EPA’s outreach efforts for 

the Final MRR and to summarize the questions that have been raised during EPA’s outreach 

activities that are being addressed by some of the proposed amendments. 

2.0 SUMMARY OF EPA OUTREACH ACTIVITIES 

EPA has conducted an extensive outreach program for the Mandatory GHG Reporting 

Rule, including meetings with trade associations and individual businesses, on-line web-based 

seminars (webinars), and training sessions for EPA Regional Offices. The following table lists 

those meetings and webinars that EPA has conducted to date, along with the month and year of 

the activity. When available, the table also includes the approximate attendance for the meeting 

or webinar. 

 
2

POST-SIGNATURE MEETINGS AND WEBINARS 

Month and Year of Information Meeting or Webinar 

Organization or Location (estimated attendance, if available) 

Sept 2009 

EPA Regional Offices Briefing (100) 

Agriculture community teleconference (100) 

State and Local Agencies teleconference (100) 

Clean Energy Group Meeting (about 40) 

State of Washington (2) 

Business Council (73) 

Call with Massachusetts on data system (2) 

Overview webinar (293) 

US Climate Action Partnership (20) 

Overview webinar (284) 

National Cooperative Refinery Association, and Van Arsdall & Associates 

Oct 2009 

Oil and Gas Compact (30) 

Detailed webinar (326) 

Portland Cement Assoc. (20) 

CENSARA(50) 

Overview webinar (217) 

Applicability Tool Demonstration (84) 

National Lime Assoc. (3) 

Detailed webinar (252) 

EEI (80) 

NACAA (75) 

Nitric Acid and Ammonia Assoc.(30) 

TFI, AISI, SMA 

Overview webinar (176) 

Detailed webinar (208) 

Air Program Managers and staff (25) 

Detailed webinar (206) 

Aluminum Industry 

Steel Manufacturers Assoc. 

Natural Gas Star 

Overview webinar (133) 

Carolina Air Pollution Control Assoc. (400) 

Applicability Tool Demonstration (238) 

Waste Management and Equipment Companies (25) 

Ohio Manure Storage 

Overview webinar (251) 

Corporate Climate Regulation, Chicago, IL 

Midwest Transportation & Air Quality Conference 

Detailed webinar (333) 

TCR/CAA (90) 

Environmental Groups (10) 

API 
3

POST-SIGNATURE MEETINGS AND WEBINARS 

Month and Year of Information Meeting or Webinar 

Organization or Location (estimated attendance, if available) 

NOV 2009 

Misc. Meetings with Industries (Refineries, Pulp and Paper, Cement) (100) 

Northeast Gas Assoc. 

Ecology and Environment, Inc. (2) 

Detailed webinar (253) 

TCR 

Tribal Air Coordinators (50) 

GHG data exchange discussion with New Mexico (8) 

API (20) 

ABA (100) 

Training for three regional cap and trade programs – DC (70) 

State-EPA Dialogue - DC (80) 

Treated Wood Council (60) 

Detailed webinar (172) 

MAPI (Manufacturing Alliance) (15) 

Environmental Services Corporation (150) 

Western Climate Initiative partner meeting – Santa Fe (50) 

Detailed webinar (171) 

Regional Climate sub-leads (40) 

Air Products (5) 

Waste Management and others (10) 

Detailed webinar (96) 

DEC 2009 

AWMA-EPA- RTP (100) 

Envirosys (4) 

Detailed webinar (50) 

ACC (5) 

National Grid 

Detailed webinar (91) 

Utilitpoint and Allegro (115) 

CARB 

NPRA and API 

Golder and Associates 

Andarko (10) 

Kinder Morgan 

EEI 

SWANA- LFGTE 

Thermo Fisher Scientific 

EPA Region 4 Training (100) 

Waste Management and others (8) 

Air Products (5) 

The Fertilizer Institute 

ADM (8) 
4

POST-SIGNATURE MEETINGS AND WEBINARS 

Month and Year of Information Meeting or Webinar 

Organization or Location (estimated attendance, if available) 

JAN 2010 

Detailed webinar (83) 

Air Products 

National Emissions Inventory (30) 

OECA- Regional offices (30) 

National Grid 

Alliance of Automobile Manufacturers (9) 

Detailed webinar (100) 

NRPA (300) 

Feb 2010 

Dedicated webinar for American Colleges and Universities (220) 

EPA Regional Inventory, Enforcement (23) 

University Challenge 

State webinar (200) 

Webinar (182) 

Iowa Landfill operators (125), Asphalt Paving Association of Iowa (70), and the Iowa Chapter of AMWA 

(60). 

Mar 2010 

Inst. Of Clean Air Companies (23) 

SWANA (200) 

EPA AFS Compliance Meeting 

Second Nature (Colleges/Universities) Panel (20) 

ECOS (50) 

PCA 

Training- EPA Regions 5 and 7 (180) 

Iowa Landfills (50) 

April 2010 

Arkansas Environmental Federation, Little Rock (160) 

NACAA Emissions and Modeling Committee (30) 

Webinar (75) 

Central TX AWMA (50) 

Chicago Exchange Meeting 

Exchange Network National Meeting (50) 

EPA Air Division Directors (20) 

National Assoc. of Clean Water Agencies 

Pepsico-Frito Lay (150) 

Pacific NW Legislative Energy Horizon Inst./AGA (35) 

May 2010 

LA, Boise, Portland Training (150, 100, 70, respectively) 

ESC Users Group (150) 

NCASI 

EPRI CEMUG (150) 
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3.0 SUMMARY OF QUESTIONS BEING ADDRESSED BY PROPOSED 

AMENDMENTS 

EPA has maintained a web-based helpline that allows individuals to submit questions 

about the final MRR, as well as on any proposed rules published since the final MRR. So far, 

EPA has resolved approximately 1,900 inquiries on the final MRR. Most of those inquiries have 

been resolved by providing further guidance to reporting entities through a web-based list of 

answers to frequently asked questions. However, for many questions, they could be resolved 

through the proposed amendments to the final MRR. 

The EPA has also held meetings with many trade associations for industries affected by 

the MRR, and many questions were presented by those trade associations that could be resolved 

through the proposed amendments to the final MRR. 

The following table summarizes the questions that have been raised on various subparts 

of the final MRR which are being addressed by the proposed technical corrections, clarifying and 

other amendments. Not all of the technical corrections and other amendments correspond to 

questions that were raised by reporters. The need for some corrections and other amendments 

were identified as a result of internal EPA review of the Final MRR, and may not be reflected in 

the following table. 
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Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

Subpart A – General Provisions 

We have a client who owns a closed landfill without a landfill gas collection system 

(no wells or headers or mechanical equipment pulling gas from the landfill). 

However, the landfill does have an open flare that operates when the landfill gas 

pressure is adequate to sustain a flame. The methane generation is sufficient to 

make the landfill subject to subpart HH. Since the flow to the flare is erratic 

(periodic) and there is no collection point per se is the landfill required to actively 

measure flow, temperature, pressure and methane concentration or is are the general 

provisions of the closed landfill adequate? 

Helpline 

Does a collection system designed to prevent offsite gas migration at the perimeter 

of the facility constitute a gas collection system as referenced in 40 CFR 98.6? We 

closed and capped the landfill and installed a pipe just inside the perimeter fence 

line. The pipe does not run through any of the Waste. The sole purpose of the 

system is to prevent possible off site migration of gas. There are a number of 

passive vents stacks installed throughout the landfill that penetrate the cap to vent 

landfill gas that collects under the cap. I have run Eq.HH-1 using default parameters 

and show about 2500 tons of CH4 for reporting year 2010. I was able to ascertain 

that the cap vent stacks are exempt from monitoring, but want to make sure about 

the migration system. 

Helpline 

Landfill passive 

vents and flares 

We have landfill clients with passive flares (flares that periodically ignite and are 

not interconnected with a system of piping one to another). These landfills generate 

CH4 in amounts equivalent to 25,000 metric tons CO2e or more per year; and these 

landfills are not required under state or federal law to flare the methane. Do these 

passive (no active vacuum, etc.) flares count as "gas collection systems" under 

Subpart HH, 40 CFR 98.343(b), and under Subpart A 40 CFR 98.6: definition of 

Gas collection system or landfill gas collection system? 

At least 4 

individuals 

Helpline 
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Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

Subpart H – Cement Production 

Analysis of clinker 

on daily basis 

If we sample clinker from a pile or storage area, this may not be representative of 

what was actually produced since some clinker may be imported to the facility. If 

one imports clinker and then measures it for CaO and MgO, it would not represent 

GHGs that are locally emitted. Since we analyze CaO and MgO daily from the feed 

systems, these values should be averaged for a monthly value used in calculations. 

At least 1 Trade Association 

From previous conference calls and descriptions of methods to determine clinker 

production, our understanding is that facilities use direct measurement in 

conjunction with other industry consensus standards to determine clinker 

production. 

Clinker production 

40 CFR 98.84(d) requires quantity of clinker produced monthly “by direct weight 

measurement using the same plant instruments used for accounting purposes.” A 

plant would not normally use this method because of inaccuracy in the 

measurements. A common accounting practice with weight measurements at 

cement plants is to reconcile data from continuous direct weight measurement 

devices with inventory accounting data (material receipts, shipments, etc.). This 

method provides greater accuracy in measurements and would help facilities meet 

5% calibration requirements required in 98.3(i) of the rule. Other facilities 

determine clinker based on direct weight measurement of the raw feed and calculate 

clinker based on a feed-to-kiln ratio. 

Previous 

conference 

calls with 

EPA 

Helpline and Trade 

Association 

analysis of the 

organic carbon 

contents of raw 

materials 

Under 40 CFR 98.84(c) it requires that total organic carbon (TOC) be determined 

for each raw material, then calculations are done for each material (%TOC x 

amount of that material) and summed. As an equivalent method, the TOC could be 

determined for a sample of the raw kiln feed and multiplied by the total amount of 

raw kiln feed. This would provide the exact same result. Would this be allowed? 

At least 1 Trade Association 

Recordkeeping for 

facilities using 

CEMs 

Facilities using CEMs noted an error in the recordkeeping provisions. Under 

98.87(a)(1) and (2) facilities are required to keep records of monthly calculated 

kiln-specific clinker and CKD CO2 emission factors. Since they are using CEMS, 

they will not have this information. These provisions were intended for those 

facilities using the methods in 98.83(d). 

At least 1 

individual and 

trade 

association 

Helpline and Trade 

Association 
8

Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

Amend 40 CFR 

98.84(b) 

40 CFR 98.84(a) requires use of ASTM C114-09, whereas 40 CFR 98.84(b) 

requires the outdated "07" edition; both sections refer back to 40 CFR 98.7, in 

which ASTM C114-09 is the approved method. In addition to correcting this 

inconsistency, would EPA be willing to make a revision that specifies "ASTM 

C114 - latest edition" since this method will be updated from time to time? 

At least 2 

individuals 

Helpline 

Subpart N – Glass Production 

Emission factors 

and definitions for 

barium carbonate 

and potassium 

carbonate 

We are a glass manufacturer with continuous melting furnaces but no CEMS for 

GHGs. The process uses limestone, dolomite, potassium carbonate, and barium 

carbonate. According to 40 CFR 98.143, we should be using eq. N-1 and N-2 for 

process CO2, and for stationary combustion sources Subpart C. However, Table N-1 

does not have emission factors for barium carbonate and potassium carbonate; 

should we calculate these factors stoiciometrically, or use another source for these 

emission factors? 

At least 1 

individual 

Helpline 

ASTM D6349-09 EPA should not restrict a certified laboratory that measures carbonate-based 

mineral mass fraction, based upon sampling and chemical analysis, to using only 

ASTM D3682-1 (Reapproved 2006) Standard Test Method for Major and Minor 

Elements in Combustion Residues from Coal Utilization Process. 

Many of the current laboratories upon which the glass industry relies are no longer 

using ASTM D3682-01, but have switched to the more interference-free (in their 

judgment) ASTM D6349. We are assuming, based upon the language provided in 

40 CFR 98.144(d), EPA would approve of using and encourage the use of 

alternative industry consensus standards adopted by organizations such as ASTM, 

ASME, API, etc., for the measurement of carbonate-based mineral mass fractions. 

Please provide this affirmation and approval to use ASTM Standard D6349. 

At least 1 Helpline 
9

Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

Subpart P – Hydrogen Production 

40 CFR 98.160 

source category 

definition 

It is unclear if all or only a portion of the processes at our facility should fall under 

the hydrogen production Subpart P and also what other subparts may apply, if any. 

At least 2 Helpline 

Calculating 

"process" and 

combustion 

emissions 

Under Subpart P, CO2 combustion emissions are required to be determined using 

the procedures outlined under Subpart C, while CO2 process emissions must be 

determined either through the Tier 4 methods for direct measurement with a CEMS 

under Subpart C, or through a fuel and feedstock material balance approach based 

on the type (solid, liquid, gaseous) of material combusted. The PSA purge gas 

produced at the hydrogen plant is combusted at the hydrogen plant heaters along 

with natural gas. Natural gas is the only other fuel/feedstock entering the hydrogen 

plant to fuel the reactors. Therefore, for a facility without a Tier 4 CEMS, the PSA 

purge gas and natural gas combustion emissions are calculated according to Subpart 

C (equation C-5), and the hydrogen plant process emissions are calculated using the 

total amount of PSA purge gas and natural gas entering the hydrogen plant 

(equation P-1). This is double counting emissions under Subpart P. Do combustion 

and process emissions need to be calculated separately or can they be reported as 

the same emissions under Subpart P? 

At least 2 Helpline 

Fuel/feedstock 

stream confusion 

when calculating 

CO2 emissions 

In Subpart P, 40 CFR 98.162(b) says to report combustion emissions from 

hydrogen production process units under Subpart C. But in 40 CFR 98.163(b), the 

combined emissions from gaseous fuel and feedstock (i.e. combustion and process 

emissions) are to be estimated using equation P-1. So if you used equation P-1 and 

also reported combustion emissions using Subpart C, then I would think this would 

be double counting the combustion emissions. Is 40 CFR 98.162(b) not really 

applicable, if using 40 CFR 98.163(b)(1) and equation P-1? 

At least 1 Helpline 
10

Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

Subpart Q – Iron and Steel Production 

Reporting emissions 

from flares 

Several manufacturers noted that Subpart Q for iron and steel plants says to use the 

procedures in subpart Y (petroleum refineries) to estimate emissions from flares, 

except use the default CO2 emissions factors in Table C-1 for coke oven gas and 

blast furnace gas in Equation Y-1. However, Equation Y-1 does not use a default 

CO2 emission factor, while Equations Y-2 and Y-3 do use the default emission 

factor and appear to be satisfactory for estimating emissions from flares. They 

asked EPA which equation(s) should iron and steel plants use for flares. 

Several Helpline and 

Trade Association 

Reporting emissions 

from 

decarburization 

vessels 

Several manufacturers noted that steelmaking facilities operate units that fall 

beyond the Rule’s formal definition of AODs, but which refine molten steel in very 

similar ways to reduce its carbon content. For example, vacuum degassers, vacuum 

oxygen degassers, Rheinstahl-Heraus systems and suppressed combustion basic 

oxygen furnaces all draw carbon from steel and/or create CO gas which is 

ultimately flared. As a result, these sources arguably fit within two distinct 

reporting categories. First, they potentially qualify as “flares,” and therefore would 

trigger reporting of “CO2 emissions from flares according to the procedures in 

98.253(b)(1) of subpart Y.” Second, their similarity to AODs supports reporting of 

“process CO2 emissions using one of the three alternate steelmaking methodologies 

specified in Subpart Q. These manufacturers requested confirmation that 

steelmaking facilities have the flexibility to report emissions from these sources 

using either Subpart Y or Subpart Q. They noted a preference to use Subpart Q. 

They noted that clarity in the rule would produce the most accurate results while 

allowing sources to avoid technical or logistical hurdles. 

Several Helpline and 

Trade Association 
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Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

Subpart S – Lime Manufacturing 

Calculating and 

reporting 

requirements for 

materials that are 

not sold 

On behalf of a number of manufacturers, a trade association requested clarification 

on the calculation and reporting requirements for materials sold and not sold, 

including those that are calcined and non-calcined. 

Several Trade Association 

Subpart Z – Phosphoric Acid Production 

AFPC manual Subpart Z, 40 CFR 98.264(b) states: “You must determine the inorganic carbon 

content of each monthly grab sample of phosphate rock (consumed in the 

production of phosphoric acid) using the applicable standard method in the 

Phosphate Mining States Methods Used and Adopted by the Association of 

Fertilizer and Phosphate Chemists AFPC Manual 10th Edition 2009— Version 1.9 

(incorporated by reference, see 40 CFR 98.7).” 

If an updated version of this reference is released would this replace Version 1.9 for 

future reporting? If it can be demonstrated to EPA that there is a more accurate 

method for measuring inorganic carbon content in the phosphate rock which a 

facility is currently using, can a facility use this methodology in place of using the 

methodology provided in Version 1.9? 

At least 1 Helpline 

Bulk sampling 

methods for 

phosphate rock 

Several large manufacturers noted that Subpart Z, 40 CFR 98.264 states that 

facilities must obtain a monthly grab sample of phosphate rock directly from the 

rock being fed to the process line and conduct the representative bulk sampling 

using the applicable standard method in the Association of Fertilizer and Phosphate 

Chemists AFPC Manual 10th Edition 2009 0- Version 1.9. They noted that 

currently the AFPC Manual does not provide specific protocols for taking a 

representative grab sample, but is planning to do so. They requested that EPA 

clarify how they should handle this situation. 

Several Helpline 
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Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

Subpart HH – Municipal Solid Waste Landfills 

The state of Florida has landfills categorized as Class III landfills which, according 

to the Florida Administrative Code Rule 62-701.200(14), includes "yard trash, 

construction and demolition debris, processed tires, asbestos, carpet, cardboard, 

paper, glass, plastic, furniture other than appliances, or other materials approved by 

the Department that are not expected to produce leachate which poses a threat to 

public health or the environment." A Class III Landfill accepts waste similar to that 

of a construction and demolition landfill. Please clarify whether, like a construction 

and demolition landfill, a Class III Landfill is also exempt from the Mandatory 

GHG Reporting Rule. 

Amend 40 CFR Hotline 

98.340(b)- Source 

Category Definition 

40 CFR 98.340(b) exempts construction and demolition landfills and industrial 

waste landfills from the reporting rules. Should the waste quantity used in Equation 

HH-1 exclude construction and demolition material and industrial waste tonnage, if 

the facility accepts and disposes of these wastes in their MSW landfill? 

At least 10 

Trade Association 

Revise Wx to 

include 

"measurement data" 

Please clarify whether, under Subpart HH of the Final GHG Rule, a MSW landfill 

may continue to determine Wx in Equation HH-1 based on the volume of waste 

entering the landfill (from tipping fee receipts or other company records) and the 

known average density of that waste. 

At least 1 Hotline 

Revise the definition 

of "DOCf" 

Table HH-1 listed several DOC for waste decomposition. Is that an option or it 

required in the calculations? The list for DOC is not all inclusive. If the landfill 

reports collecting "residential waste" or "commercial waste," what category would I 

list that and what DOC and decay rate values do I use? Is this is the only options to 

use in the calculations? 

At least 1 Hotline 

Revise definition of 

"S" to read, "Start 

year of calculation." 

Can you please clarify the following variables listed in subpart HH: 

X = Year in which waste was disposed. 

S = Start of year calculation . Use the year 50 years prior to the year of the 

emissions estimate, or the opening year of the landfill, whichever is more recent. 

T = Reporting year for which emissions are calculated. 

At least 1 Hotline 
13

Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

The procedures for computing methane generation in Subpart HH include 

provisions for “leachate recirculation,” in particular the precipitation-based values 

for the methane decay rate factor, k. Specifically, the decay factor increases with 

leachate recirculation to be equal to the value for “precipitation over 40 

inches/year,” presumably on the theory that gas generation will increase as a result 

of the higher moisture content from leachate recirculation. 

However, leachate recirculation is undefined in the MRR, and it seems that landfills 

that “recirculate” very limited volumes of leachate, and/or which recirculate 

leachate for limited periods could be required to use a value for the decay rate 

which is inappropriately high. Landfills that recirculate limited volumes of leachate 

and/or that recirculate for a limited period should be permitted to demonstrate that 

the resulting total (average precipitation + average annual leachate recirculation) 

meets the applicable precipitation based k of (1) < 20 in/yr, (2) 20-40 in/yr, or (3) > 

40 in/yr. 

Amend the Hotline 

definition for k in 

Eq. HH-1 

When determining landfill generation using the LandGEM model, I have 

developed both a site specific k and Lo factor for the years when waste composition 

data were available. When waste composition data were not available, I used the 

default factors as provided in Table HH-1. I then ran LandGEM twice (once for the 

years with waste composition data and once with default data) and then summed the 

methane generation. Is this correct? Also if you have site specific waste 

composition data to develop a site-specific k factor, must you also use the data to 

develop the Lo factor? Or, can you mix default and site-specific factors in the same 

model? 

At least 3 

Hotline 

Add 40 CFR 

98.343(a)(3) - allow 

the use of truck 

counts and 

capacities as an 

Recognizing that the MRR includes methods for calculating historic yearly waste in 

place, are landfills without scales allowed to use a waste-in-place conversion 

method other than the MRR’s methods? Often such landfills have their own 

methods of estimating tons disposed based on truck size and they have kept 

accurate records over the years. 

At least 10 Trade Association 
14

Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

40 CFR 98.344(a) states that landfill scales must meet requirements of the 2009 

version of NIST Handbook 44. Some States reference previous versions of this 

handbook for current commercial scale regulations. Will State regulations for 

commercial scale requirements be acceptable alternatives for tracking incoming 

waste? 

Trade Association 

Is it ok to estimate the weight of the small loads (pickup trucks, etc.) based on an 

average weight for similar small loads? I ask because otherwise, each vehicle would 

have to weigh out which is burdensome for the scale attendant. 

Hotline 

acceptable method 

of determining 

waste quantity 

landfilled when 

scales are not in 

place for year 2010 

or later. 

Please clarify whether, under Subpart HH of the Final GHG Rule, a MSW landfill 

may continue to determine Wx in Equation HH-1 based on the volume of waste 

entering the landfill (from tipping fee receipts or other company records) and the 

known average density of that waste. 

Hotline 

Revise equation 

HH-4 and the terms 

in the equation to 

more clearly allow 

for daily averages 

With regards to Recovered methane, equation HH-4, it states that if you are using 

weekly monitoring to use N = 52, however looking at the units that the calculation 

works out to, it would appear that 365 days is more appropriate. Can you please 

clarify? 

At least 1 Hotline 

Amend 40 CFR 

98.343(b)(2)(ii) - 

clarify what is 

meant by weekly 

sampling. 

How does EPA define "weekly" sampling? At least 1 Hotline 
15

Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

Is there an inherent conflict in the way Equation HH-4 at 40 CFR 98.343(b)(1), as 

written, corrects for moisture content of landfill gas? As currently written, there is 

only one moisture correction factor in the equation, given as (1-(fH2O)n). Given 

the description of variables (V)n and (C)n, it appears to apply to both. In the 

description of (V)n, it states that if CH4 is measured on a dry basis and the flow rate 

is automatically corrected for moisture, then the factor (1-(fH2O)n) should be set 

equal to 1. However, in the description of (C)n, it states if CH4 is measured on a 

wet basis, then the factor (1-(fH2O)n) should be set equal to 1. Given the way the 

equation is written, both conditions cannot exist. Since many landfills currently use 

systems that measure flow rate automatically corrected for moisture, but CH4

concentration is typically measured on a wet basis, Equation HH-4 could not be 

used as written. 

Hotline 

Please clarify the issue of moisture content. When does/doesn't it need to be 

quantified? How is it quantified? Can a standard table be used rather than 

measuring it? 

Trade Association 

Amend Equation 

HH-4 and 40 CFR 

98.343(b)(2)(iii)(B) 

- clarify when the 

moisture content 

measurement is 

required. 

There are no QA/QC procedures listed under 40 CFR 98.344 for monitoring 

moisture content of landfill gas. Are assumed values (i.e., saturated conditions) for 

landfill gas moisture content acceptable for equation HH-4? 

At least 10 

Trade Association 

"Active" and 

"Passive" Gas 

Collection Systems 

The rule states that facilities that collect and control landfill gas (LFG) must 

calculate the annual quantity of CH4 recovered and destroyed based on continuous 

monitoring of gas flow rate. Would this continuous monitoring requirement apply 

to a landfill that passively vents through multiple locations equipped with small 

vent flares (an example of a vent flare is the "Solar spark" at landfill.com)? 

Typically, these flares are not equipped with any type of flow or methane 

monitoring devices. In summary, are passive venting systems subject to the same 

continuous flow monitoring requirements as active systems that use blowers to 

collect LFG? 

At least 8 Hotline 

Amend 40 CFR 

98.344(b) re: 

portable CH4

monitoring devices 

Are portable meters that determine methane concentration acceptable for 

compliance with the rule requirements? 

At least 10 Hotline and Trade 

Association 
16

Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

Clarify sampling 

location 

Subpart HH specifies determining the CH4 content by EPA Methods 25a/25b. It 

states that once per year a GC methodology must be used to determine a correction 

factor (3 samples/hr; 20 min apart). Is this requirement per sample location (i.e. one 

per destruction device) or per monitoring device (i.e. one per GEM2000, since the 

same GEM2000 would be used at all of the monitoring points)? Or, is it our 

discretion to use whichever fits the situation better? 

At least 1 Hotline 

Amend 40 CFR 

98.344(c) - clarify 

the calibration 

requirements for 

flow meters. 

By what date must flow meters and LFG meters be calibrated? 40 CFR 98.3(i)(1) 

states that they should be calibrated by April 1, 2010. 40 CFR 98.344(c) says that 

flow meters shall be calibrated prior to the first year of reporting. 

At least 1 Trade Association 

The surface area under each cover type at a landfill will vary over the course of a 

year. For compliance with 40 CFR 98.346(f), what is the date for which the surface 

area numbers should be calculated (e.g., Jan 1, Dec 31, or May 24)? 

Amend 40 CFR Hotline 

98.346(f)- clarify 

the reporting 

requirements for 

surface area 

Data Reporting under 40 CFR 98.346(f) requires the oxidation factor for each cover 

type used in the calculation. However, the equations HH-7 and HH-8 required a 

default value of 10%. Can supported alternate oxidation factors be used in the 

calculations? 

At least 2 

Trade Association 

Amend Table HH-3 

- delete the 

reference to average 

depth of waste 

within an area 

Table HH-3 includes "waste depth" in the discussion of collection efficiency 

calculations. However waste depth does not appear to be used in any calculations. 

This appears to be a carry over from the use of the SWICS method for estimating 

collection efficiency. Given that the methods in Table HH-3 default to the midrange of the SWICS calculations, waste depth appears unnecessary. However, per 

40 CFR 98.345(i)(7) waste depth is to be included in the annual report. 

Besides the annual report, is there any reason for tracking the landfill waste depth of 

each landfill area (i.e., is it needed for any calculations)? Can this be eliminated 

from the annual reporting requirement as unnecessary? 

At least 1 Hotline 
17

Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

Amend Table HH-3 

- soil cover 

Table HH-3 - This table mentions H2, H3, H4, and H5, which are defined as the 

average depth of waste in each cover area. However, this parameter doesn't seem to 

be incorporated in any of the equations or reporting requirements. Does the 

collection efficiency calculation consider depth/height? Or only surface area? 

At least 1 Hotline 

Subpart LL – Suppliers of Coal Based Liquid Fuels 

Clarification on 

products that leave 

the facility but were 

not further refined 

or otherwise used on 

site (e.g. products 

stored in a tank). 

See questions that support an amendment for the same issue in subpart MM. It is 

reasonable to use subpart MM questions as a proxy for subpart LL issues because 

the reporting procedures are nearly identical due to similarity in facility type and 

operation and because no subpart LL facilities are currently in operation to submit 

operational questions. 

At least 1 EPA email 

correspondence 

with trade 

associations 

Subpart MM – Suppliers of Petroleum Products 

What is the definition of a crude oil batch per 40 CFR 98.396(a)(20)? Crude from 

one source may not vary much over time. Is that what is meant by “batch”? For 

crude oil batches, if a refinery receives the same grade of crude oil continuously 

over a period of, for example, six months, does that constitute one batch of that 

crude oil, six batches, or something else? 

For the crude oil batch, would it be acceptable to sample the crude in the charge 

tank(s) daily and use that analysis to define a "daily" batch that would be equivalent 

and representative of the volume to the charge rate for that day? 

40 CFR 98.394(d) requires the measurement of the API gravity and sulfur content 

of each batch of crude oil. As the crude is continuously supplied from one pipeline 

system, we would like to know what the definition of batch would be in this 

situation. Alternatively, would quarterly sampling suffice? 

"Batch" definition 

Can the April 1st deadline for best available data also be applied to the definition of 

a batch of crude oil? I.e., could refineries continue to report crude oil batch 

At least 5 Helpline and EPA 

correspondence 

with trade 

associations 
18

Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

quantities based on their respective definitions of a “batch”? 

If a third party pipeline receives both domestic and foreign crude deliveries, is the 

refinery it supplies responsible for determining country of origin? Can we just 

report sample data? 

Clarification of 

weighted average 

API gravity and 

sulfur content from 

batch samples 

In Subpart MM, specifically 40 CFR 98.396(a)(20), can the crude batch volumes 

reported be totaled for the year by type of crude, rather than each individual batch? 

Can the crude oil API gravity and sulfur content for the batches also be totaled for 

the year for reporting of all batches by crude type? 

At least 1 Helpline 

Recordkeeping 

amendment for API 

gravity and sulfur 

content 

Per 40 CFR 98.397, “Reporters shall maintain laboratory reports, calculations and 

worksheets used in the measurement of API gravity and sulfur content for every 

crude oil batch reported under this subpart.” What if the only available record is a 

crude ticket issued by someone else? 

At least 1 EPA 

correspondence 

with trade 

associations 

A terminal that is part of a refinery facility brings in ethanol and then sends the 

ethanol out. The ethanol is not blended or co-processed prior to being sent out. We 

believe that it is not reportable under Subpart MM. Please confirm that our 

understanding of the rule is correct. 

If refinery A exchanges a finished hydrocarbon product with refinery B, and that 

product is not further processed by refinery A (but instead enters commerce directly 

from either refinery tankage or terminal tankage), does the carbon content of that 

exchanged product need to be reported by refinery A? 

Clarification on 

products that leave 

the refinery but 

were not further 

refined or otherwise 

used on site (e.g. 

products stored in a 

tank). 

What is meant by "or otherwise used on site" for the Subpart MM equations using 

feedstock quantities? 

At least 3 Helpline and EPA 

correspondence 

with trade 

associations 
19

Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

In 40 CFR 98.393(f)(1), EPA has not addressed the issue raised by EPA during rule 

proposal, i.e. “...should (reporters) be allowed to combine default CO2 emission 

factors to develop alternative factors for fuel reformulations according to the 

volume percent of each fuel component...” (Page 16572, proposed rule). 

Since CO2 emissions are based on the carbon content of the fuels, multiplying the 

volume of each pre-mixed fuel by its respective fuel-based emission factor and 

summing the result would provide an adequate estimate of CO2 for the fuel mixture. 

EPA should add a clarification to Subpart MM regarding estimating emissions from 

fuel mixtures without the need to use carbon content measurements. 

Optional method for 

calculating/reporting 

blended products 

Many petroleum refineries have co-located terminals adjacent to them. This 

presents a challenge in accounting for products especially if the refinery sends some 

of their products to the terminal for blending. If the terminal is counted as part of 

the “facility” it would be part of the “refinery.” Therefore, a plain English reading 

of subpart MM would move accounting for some products from the refinery gate, to 

the terminal gate. Would reporters be expected to track products to and through the 

co-located terminal and account for them as they leave the terminal gate? How 

would reporters account for the ethanol and additives with naphtha that are added at 

the terminal? This makes tracking and reporting products confusing and 

cumbersome. 

At least 2 Hotline and EPA 

correspondence 

with trade 

associations 

"%vol" definition to 

exclude denatured 

ethanol 

We add fuel ethanol into gasoline at a refinery terminal. We receive the fuel ethanol 

by truck, place it in a storage tank, and put it in gasoline trucks leaving the refinery 

terminal. No processing is involved. Because fuel ethanol contains denaturant, we 

have found the reporting requirements for denaturant to be confusing. We believe 

that we should only report the petroleum product produced at the refinery that went 

into the gasoline leaving the refinery terminal and disregard the fuel ethanol. 

At least 3 Helpline 
20

Summary Of Questions And Issues From The EPA Helpline And Trade Associations Being Resolved By The Proposed 

Technical Corrections And Other Amendments

Technical Issue Question Submitted to EPA 

Type and 

approximate 

number of 

submittals 

Reference 

(Helpline or Trade 

Association 

materials) 

Equation MM-8 of the MRR requires that 2.5% of ethanol blended with petroleum 

products be included in the CO2eq calculation. However, the ethanol at a refinery is 

purchased and then blended with the petroleum product. Thus, the denaturant that is 

included in the blended ethanol would be double-counted if included in the 

Equation MM-8 calculation and reported under 40 CFR 98.396 since it should be 

included in the Subpart MM report for the fuel supplier that initially supplied the 

petroleum product denaturant to the ethanol plant. We assume that Equation MM-8 

should be applied when ethanol with the blended denaturant originates from the 

refinery that is doing the blending. Therefore, to provide accurate Subpart MM 

reporting to the EPA without double-counting, we believe that the purchased 

ethanol that is blended with petroleum products should not be reported under 

Subpart MM. Please confirm that this interpretation of the rule is correct. 

If we have an ethanol line from the dock at the refinery to the terminal, do we need 

a meter there for the purpose of this rule? Our interpretation of Subpart MM is that 

any biomass, such as ethanol, would be subtracted from the emission totals at the 

refinery but only if gasoline and ethanol are blended at the facility. Also, should 

anything downstream of a refinery, such as a terminal, not be subject to the rule to 

avoid double counting?