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From: Palazzolo, Michael A. [Michael.Palazzolo@alcoa.com]

Sent: Saturday, December 10, 2011 10:45 AM

To: Boyd.Rochelle@epamail.epa.gov

Cc: psohi@aluminum.org; Green, David A.; Kler.Denis@epamail.epa.gov

Subject: FW: SAPU Calculations

Attachments: RRR SAPU Calc Clarification.pdf

Rochelle, 

I reviewed the attached memo and agree with the stated approach except for the 

interpretation that production rates used during the performance test would be used to 

calculate the daily SAPU limit. The memo says that feed/charge rates used in the 

emission limit calculation “should be consistent with the feed/charge rate at which the 

facility operated during their performance test to demonstrate compliance.” This needs 

further clarification as discussed below. 

The SAPU emission limit should be different each day, depending on what equipment is 

operated that day. As a simple example, consider an existing uncontrolled SAPU that 

has two Group 1 melting furnaces and one in-line fluxer. During normal operation (and 

for the compliance test), the emission limit would be calculated based on all three units:

For particulate matter, the Group 1 Melting furnaces have a limit of 0.4 lb PM/ton and 

the in-line fluxer has a limit of 0.01 lb PM/ton. 

For this example, the Emission Limit is at a maximum for normal operations because two 

of the three units have a high allowable emission rate (0.4 lb/ton) while one has a low 

allowable rate (0.01 lb/ton). 

However, if one melting furnace is not operating (say on a weekend day), the limit for 

that day should be a lower value because the facility is averaging emissions between 
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only one unit with a high allowable emission rate (0.4 lb/ton) and one unit with a low 

rate (0.01 lb/ton). 

 

Defining a fixed SAPU limit based only on production rates during the stack test would 

make the MACT standard less stringent during periods when some equipment is not 

operating. I do not believe this was EPA’s intent when the SAPU averaging approach 

was developed. 

Note that the throughput used to calculate the daily Emission Limit should be the 

amount of feed or aluminum produced for each emission unit during the 24-hr period. 

The equations in Section 63.1505(k) create confusion in this regard. In Section 

63.1505(k), Ti is defined as “the feed/charge rate for individual emission unit I”. This 

definition for Ti is not clear and incomplete. 

For compliance testing, the SAPU limit must be calculated based on the throughput 

during the test. So, Ti would be defined in terms of “amount of feed or aluminum 

production during each stack test run”. (Average of three runs to demonstrate initial 

compliance.) However, for the daily SAPU calculation, Ti should be defined the same as 

it is in Section 63.1510(t): “the amount of feed or aluminum produced for each emission 

unit during the 24-hr period”. This would solve the confusion. 

Please let me know if you would like a phone call to discuss this question further. I still 

owe you information on the New SAPU example we discussed during our meeting. I am 

traveling Monday and will try to get you something on Tuesday. 

Regards, 

Mike 

Michael Palazzolo 

Alcoa, Inc. 

201 Isabella Street 

Pittsburgh, PA 15212-5858 

Ph: 412-553-4832 

From: Boyd.Rochelle@epamail.epa.gov [mailto:Boyd.Rochelle@epamail.epa.gov] 

Sent: Tuesday, December 06, 2011 4:16 PM 

To: Paul Sohi 

Cc: Palazzolo, Michael A. 

Subject: SAPU Calculations 
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Here is the interpretation memo for SAPU calculations. We will clarify in the preamble the correct way for SAPU 

calculations if we need to. Plants in Region IV are doing it this way. Please provide comments. 

Also, by Friday if Mike could provide calculation examples for Existing SAPU with co-controlled and uncontrolled units, 

New SAPU calculations for co-controlled units, New SAPU for uncontrolled units in accordance with 1505, 1510 and 

1513. Thanks.
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

MAR 9 2007 

OFFICE OF 

ENFORCEMENT AND 

COMPLIANCE ASSURANCE 

MEMORANDUM 

SUBJECT:· Clarification of the Calculations for Se~ondary Aluminum Processing Units in the 

Secondary Aluminum NESHAP 

FROM: 

TO: 

Michael 

Compliance 

S.Alushin, 

Assessment 

Director 

and Media 

~j.-Programs ~ Division 

Office of Compliance 

Regional Air Division Directors 

The purpose of this memorandum is to provide to the regions, states, and local agencies a 

·clarification of the calculations for secondary aluminum processing units (SAPU) as required in 

the National Emission Standard for Hazardous Air Pollutants (NESHAP) for Secondary 

Aluminum Production, 40 CFR Part 63, Subpart RRR. 

An SAPU is defined in 63.1503 as: 

An existing SAPU.means all existing group 1 furnaces and all 

existing in-line fluxers within a secondary aluminum production 

facility. Each existing group 1 furnace or existing in~line fluxer is 

considered an emission unit within a secondary aluminum 

processing unit. A new SAPU means any combination of 

individual group 1 furnaces and in-line fluxers within a secondary 

aluminum processing facility which ~ither were constructed or 

reconstructed after February 11, 1999, or have been permanently 

redesignated as new emission units pursuant to §63.1505(k)(6). 

Each ofthe group 1 furnaces or in-line fluxers within a new SAPU 

is considered an emission Unit within that secondary aluminum 

processing unit. 

, Intemet Address (URL). http://www.epa.gov 

Recycled/Recyclable. Printed with Vegetable Oil Based Inks on 100% Postconsumer. Process Chlorine Free Recycled Paper 
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Subpart RRR has three sets of equations that are to be used for SAPU emissions 

calculations which are explained below. While the specific equations below are for calculating 

SAPU particulate matter emis~ions, this clarification applies to the equations for hydrog~n 

chloride and dioxinlfurans as well. 

Section 63: 1505(k) 

Section 63 .1505(k) provides the following equation that is to be used to calculate an 

average e~ission limit for SAPUs. 

n (Eq. ]} 

I (Tti <.I 

i I 

Iri the equation above, Tti equals the feed/charge rate for an individual emission unit. 

Some regulatory agencies have requested clarification as to what feed/charge rate should be used 

in this SAPU calculation. The feed/charge rate utilized in the equation should be consistent with 

the feed/charge rate at which the facility operated during their performance test to demonstrate 

compliance. The performance testing requirements in Sections 63.1511(b)(1), (2), and (3) 

specify that: 

(1) rhe owner or operator must conduct each test while the affected source or 

.. emission unit is operating at the h~ghest production level with charge materials 

representative of the range of materials processed by the unit and, if applicable, at 

'the highest reactive fluxing rate. 

(2) Each performance testfor a continuous process must consist of 3 separate 

rlins; pollutant sampling for each run must be conducted for the time period 

specified in the applicable method or, in the absence of a specific time period in 

the test method, for a minimum of 3 hours. 

(3) Each performance test for a batch process must consist ofthree separate runs; 

\ pollutant sampli~g for each run must be conducted over the entire process operating 

cycle. 
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The performance testing requirements state that the performance tests must be conducted 

at the highest production level and consist of three separate runs. Therefore, the feed/charge rate 

utilized in calculating the SAPU emission limit should be the average feed/charge rate from the 

three separate runs conducted during the performance test. . 

Also in the equation above~ Lti is the individual emission unit emission limit from 

Sections 63 .l,505(i) and 0), which is for group 1 furnaces and in-line fluxers, respectively. The 

SAPU emission limit is a fixed emission limit until the emission units in the SAPU are retested. 

Section 63.1513(e) 

Once th~ performance test has been validated by the appropriate agency, the SAPU 

emission limit can be calculated for each pollutant. Section 63.1513(e) provides the equations to 

determine the SAPU's compliance status with the particular pollutant's calculated SAPU 

emission limit. ' 

n 

~'(E . L 1,,- t Ipl'vl 

ECPM 

i;~, r ' 

n (Eq. l); 

I{Tti ) 

j: I 

In the equation abo.ve, Eti is the measured emissions for the individual emission unit 

during the performance test and Tti is the average feed/charge rate for the individual emission 

unit during the performance test. Section 63.1513(e)(1) states that the SAPU is in compliance if 

the mass-weighted emissions for the SAPU using the equations in Section 63 .1513( e) are less 

than or equa1 tothe SAPU emission limit that was calculated using the equations in Section 

63.1505(k). 

Section 63.1510(0 

Once the SAPU has demonstrated compliance with the SAPU emission limit for the 

particular pollutant, Section 63.1510(t) requires that 3-day, 24-hour rolling average emissions be . 

calculated on a daily basis. 
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11 

L.{Ti xER j ') 

E

day · i ). 

n 

(f. .. ~ I 4 \ \. .. .t.. . , 

L.Ti 

i" l 

In the equation above, Tj is the total feed/charge rate for ea~h emission unit for the 

24-hour period, and ER is the measured emission rate ofthe particular pollutant from the 

performance test. The rule describes how to calculate the 3-day, 24-hour rolling average 

emissions as follows: 

(1) Calculate and record the total weight of material charged to each emission unit in the 

secondary aluminum processing unit for each 24-hour day of operation using the . 

feed/charge weight information required in paragraph (e) of this section. If the owner or 

operator chooses to. comply on the basis of weight of aluminum produced by the emission 

unit, rather than weight of material charged to the emission unit, all performance test 

emissions results and all calculations must be conducted on the aluminum production 

weight basis. 

(2) Multiply the total feed/charge weight to the emission unit, or the weight of aluminum 

produced by the emission unit, for each emission unit for the 24-hour period by the 

emission rate (in lb/ton of feed/charge) for that emission unit (as determined during the 

performance test) to provide emissions for each emission unit for the 24-hour period, in 

pounds. . 

(3) Divide the total ,emissions for each SAPU for the 24-hour period by the total material 

charged to the SAPU, or the weight of aluminum produced by the SAPU over the '24-hour 

period to provide the daily emission !ate for the SAPU. 

Therefore, the feed/charge weights will be measured and recordea for each operating 

cycle or time period used during the performance test, then a 24-hour feed/charge weight for each 

emission unit will be calculated~ The 3-day, 24-hour rolling average emissions calculated from 

the three most recent days will be used to compare to the SAPU emission limit which is 

calculated using Section 63.1505(k). The SAPU is in compliance ifthe 3-day, 24-hourrolling 

average emissions do not exceed the SAPU emission limit that is calculated using the equation in 

Section 63.1505(k), per Section 63.1505(k)(1). 
i. 

• 

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Sections 63 .1506( d)(3) and 63.151 O(t)(1) allow aluminum produced to be used instead of 

feed/charge provided that certain conditions are met If the facility decides to use aluminum 

produced, then Section 63.151 o (t)(1 ) requires that all performance test emission results and all 

calculations must be conducted on the aluminum production weight basis when complying with 

the SAPU emission limit. . 

Note that Subpart RRR allows facilities with emission units within an SAPU to 

demonstrate compliance with either the SAPU emission limit which is calculated, or each 

individual emission unit may demonstrate cOf!1pliance with the individual emission limit through· 

a performance test. 

cc: 

If you have any questions, pl~ase contact Scott Throwe of my sta~f at (202) 564-7013. 

Regional Air Enforcement Branch Chiefs 

Todq Russo, Region 4 

Jeff Oahris, Region 5 

Tanya Boomer, Region 5 

Richard Tripp, Region 7 

Joshua'Rickard, Region 8 

Stanley Tong, Region 9 

John Brock, Region 9 

Donnalee Jones, OAQPS 

Mamie R. Miller, CAMPD 

Michael S. Alushin, CAMPD 

Scott Throwe, CAMPD 

/