EPA - HQ - OAR- 2010 - 0544 - DRAFT - 0203.doc Page 1 of 7

1 **MEMO RANDUM**  **From:** Donna Lee Jones, Ph.D., U.S. Environmental Protection Agency , Office of Air

Quality Planning and Standards, Research Triangle Park, NC (D243 - 02) Jones.DonnaLee@epa.go v **Date: September 30,**  **2009 Subject:**  Rule Improvements for Secondary Aluminum Production NESHAP (40 CFR Part 6 3 Subpart RRR) **1 .**  **Definitions and Applicability**  **Clean Charge** o Add more quantitative measure of “clean” charge/ scrap .  Add specific methods to be used to prove scrap is entirely free of contaminants (see Operation & Monitoring, below) . o Add specifications for cleaning processes (e.g., for runaround scrap) , such as:  M inimum residence time and temperature for thermal drying process .  M inimum RPM speed and residence time for centrifuging processes . o Add that sows, ingots, and t -bars with only paint markings are still considered clean charge. o Add OECA clarification on how to ‘know’ if it is clean and/or entirel y free of paints, coatings, and lubricants :  Must have some knowle dge of the processes applied to the scrap material b y maintaining direct control of the scrap or by knowing the processes utilized by

outside entities that have supplied the scrap.  Must h ave some knowledge of the history of that scrap material such that they may know that the material is “entirel y free of paints, coatings, and lubricants.” “ Entirel y free” indicate s that the scrap must contain no paints, coatings, or lubricants. This k nowledge can be gained through several methods. One method would be to maintain direct control of the scrap material being processed and only process scrap generated within the facility or from other facilities within the same company that the owner or operators knows has not been subjected to paints, coatings and lubricant s or where they know paints, coatings or lubricants have been removed consistent with the definition of “Clean charge”. Similarly, the owner or operators may also process scrap from outside entities where they are familiar with the history

of the scrap and therefore, know that the scrap meets the definition of “ c lean charge.” o Add OECA clarification on methods that would not allow owners or operators to “know ” scrap is clean:  Secondary

aluminum production facilities may receive bales of aluminum scrap from scrap vendors. The scrap is accumulated from a variety of sources and the owner or operator may conduct a cursory inspection of the scrap bales to determine whether the material isEPA - HQ - OAR- 2010 - 0544 - DRAFT - 0203.doc Page 2 of 7

2 “entirel y free of paints, coatings, and lubricants.” This ty pe of insp ection is insufficient and does not provide the owner or operator sufficient information regarding the scrap such that they may know that the scrap is “entirel y free of paints, coatings, and lubricants.” Even more thorough inspections of the scrap may be insufficient, since the scrap may

contain clear coated materials or lubricants not visible on the outside of the scrap. Consequently , scrap inspection alone may not provide owners or operators sufficient knowledge of the scrap such that they can know that the scrap is “entirel y free of paints, coatings, and lubricants.”  **A nodized**  **A luminum**  **Scrap** o Exclude anodized aluminum s crap from the clean charge definition since dyes may be used as part of the anodizing process, which could volatilize in the furnace and c ontribute to THC or D/F emissions.  **Secondary Aluminum Processing Unit ( SAPU** **) -**  **Existing vs.**  **New** o Clarify definitions to indicate that there can only be ONE existing SAPU and ONE new. The existing/new SAPU includes all existing/new Group 1 furnaces and all existing new inline fluxers at a single facility .  **Scrap S**  **hredders** o Clarify that all scrap shredders processing other than clean scrap are subject to the rule . o Clarify that all scrap shredders that generate visible emissions as determined by EPA Method 22 are subject to the rule regardless of whether scrap is considered clean or not. o Exempt shredders that always process clean scrap and don’t generate visible emissions as determined by EPA Method 22 . Minimally , exempt from periodic testing .  **Thermal Chip D**  **ry ers**  o Clarify that a device that uses heat to evaporate water, oil, or oil/water mixtures from unpainted/uncoated aluminum chips is subject to subpart RRR.  **F urnaces**  **that Are**  **Affected Sources**

o **Identical Furnaces**
- Identify criteria under which furnaces may be defined as “ identical .”  Examples of possible criteria : temperature, processing rate, design, scrap materials charged to the furnaces, etc. o **Stationary Furnace with Internal Heaters -**  Clarify that a furnace that is not portable and has internal heaters and is used to hold molten aluminum is a furnace under subpart RRR.  **Furnaces that are Not**  **Affected Sources**

o **Transport Pot s**  **-** Clarify that pots used to transport metal to customers are not furnaces . o **Diecaster Holding Furnace -**  Clarify that a furnace used b y a diecaster that only metals or holds clean charge is not a subpart RRR furnace (diecaster does not have a sweat furnace or thermal chip dryer or scrap dryer , and does not use flux or only uses nonreactive nonHAP flux)EPA - HQ - OAR- 2010 - 0544 - DRAFT - 0203.doc Page 3 of 7

3  **Sweat Furnace**

o Clarify that any

furnace that charges objects containing aluminum and is tipped to pour out molten aluminum is a sweat furnace. ( Does this mean that tapping to get the melted aluminum out makes a furnace a Group 1 or 2 furnace?)  **Bale B**  **reaker**

o Clarify that this is a device used to b reak the ties holding a bale of aluminum scrap before it is fed into the shredder and which i s not also a scrap shredder.  **Scalpers**

o Clarify that scalpers used to remove rough spots from ingots prior to rolling into various product shapes are not subject to subpart RRR and are considered to be equipment in aluminum product manufacturing.  **Capture and Collection System** -- Add definition
.  **Residence T**  **im e of an**  **A fterburner**  o Clarify that this is the total time required for gases to pass through the afterburner co mbustion chamber, which does not include the furnace, ductwork , or stack.  **Fluxes** o **Cover Flux**  **i n Rotary**  **o r Other Agitated Furnaces**   Clarify that any

f lux used in a rotary

furnace is by

design agitat ed ; therefore, any flux used for “cover” or otherwise in thi s ty pe of furnace is considered reactive  Add definiti ons for agitated and non - agitated furnaces. o **Cover F**  **lux Used to Also Remove Impurities**   Clarify how to distinguish between cover flux that only prevents oxidation vs. cover flux that also removes impuritie s ( and is therefore reactive?) which can result in HAP emissions at a later point. o **Continuous vs.**  **, B**  **atch (intermitt en**  **t) F**  **lux A**  **dditions**  Add definition s so that different monitoring strategies can be set (see below) .  **Feed/c h**  **arge R** **ate** o Clarify that the feed/ch arge rates obtained during performance tests should be used to calculate the emission limit for each pollutant from each SAPU  **Thermal Delaminating of Aluminum Scrap and Mechanical Granulation of Recovered Metal**  **are Affected Sources under Subpart RRR**  o Heat i s used to separate aluminum foil from paper and plastic in scrap, o Chambers operate at a maximum temperature of 900F and no melting of the recovered aluminum occurs in the chamber o Subsequent melting of recovered aluminum need not occur at the same facility that conducts the recovery operation.EPA - HQ - OAR- 2010 - 0544 - DRAFT - 0203.doc Page 4 of 7

4 **2 .**  **Reporting**  **Area Sources** : Add annual compliance certification reports ( currentl y exempt from Title V permits) . Similar to requirements in EPA’s 40 CFR part 63 area source program.  **Semi -**  **annual Report Formats** . Add minimum requirements to be included in these reports. **3 .**  **O perating and**  **M onitoring**  **R equirements**   **Add /**  **expand Monitor** **i ng**  **Requirements for**  : o Capture and collection systems o Reactive flux injection rate o Lime injection rate (lb/hr) verification during daily operation o Feed/ charge weight at scrap dryers/delacquering kilns and decoating kilns  Establish feed/charge weight parameters during performance test o Reactive flux injection furnaces “ charge and top ” operations  Include alternative process control monitoring? o Scrap inspection  Add how to collect representative sample for oil content.  Add how to correlate visual inspections with physical measurements o Ceramic candle filter control devices o Molten level at passage between sidewell and hearth during reactive fluxing  Spe cify

how to establish molten level  Specify

different monitoring intervals for continuous charging (@15 minutes) vs. , batch (@batch charge addition) o Control measures not required by rule but used during performance test to control pollutants with emission l imits under the rule.  For example, ammonia or carbon injection rates used to control D/F.  **Reduce Monitoring Requirements:**  o Solid flux  Add monitoring only when solid flux is added for batch/intermittent flux additions; keep monitoring for every 15 minutes with continuous flux additions.  **O&M Plan Revisions** o Require submission for approval of ANY changes and forbid operati o n before plan is approved. o Require minimum time (3 months?) to submit for approval prior to a planned change in operation. o Clarify option s under 63.1510(o) (Site - specific monitoring for Group 1 furnace without add- on air pollution control devices) o Clarify that 63.1510 does NOT appl y to a SAPU that has already demonstrated compliance on an individual unit basis , as per 63.1510(u). o Require repeat testing of actual volumetric flowrates of hood s during annual inspection of hood operational integrity  **A llowable**  **Operating Conditions** o Clarify f

eed/charge rate in operation vs. during performance testsEPA - HQ - OAR- 2010 - 0544 - DRAFT - 0203.doc Page 5 of 7

5 o Clarify that can exceed performance test charge weight as long as the performance test is still representative of facility operation at highest emission level of all pollutants . For example, if clean charge is added to regular charge in Group 2 furnace and final weight is above performance test rate but not if clean charge is excluded, or if all clean charge us used in a Group 2 furnace at feed rate higher than the test rate.  **NOT Allowable Operating Conditions**  o [Add any situations that need to be listed]  **Thermocouple C**  **alibration for A**  **fterburners** o Clarif y that a second thermocouple can be used in a dual calibration system instead of the rule required calibration; if minimally weekl y checks are done for agreement of the dual thermocouples. **4 .**  **Performance Testing**  **F eed/charge**  **R ate**  o Clarify requirements to determine feed/charge rate used during performance test that will be used to calculate emission s for each pollutant. o Clarify that all t

he feed/charge rate during ALL performance testing is required to be the level that is likely

to create the highest emis sions (of pollutant known to be the highest emitters, or all pollutants, if possible)  **Frequ e**  **ncy of T**  **est i**  **ng** o Clarify that testing ne eds to be done every five ye ars to show compliance regardless of level of emissions.  **Multiple Emission**  **Units :**  o Clarify for SAPU and non - SAPU ducted to a common control device . o Clarify for i dentical furnaces (to reduce individual testing) .  **Temporary E**  **nclosures for C**  **ollect i**  **on of F**  **ugitive E**  **mis s**  **ions** o Add requirement to capture fugitive emissions during testing  Add requirement to account for fugitives that could be lost from furnace or other doors being opened during tests.  Add requirement for temporary enclosure to be used if not possible to capture fugitives otherwise.  **Additional Data**  **to be Collected during**  **Performance Tests** o Require do cumentation of the ty pe of scrap processed during performance test . o Require testing

/ documentation of flow rate for each hood and capture/collection system. o Require testing

/ documentation operating levels of control measures used during performance test to reduce emissions although not explicitly required b y rule (e.g., ammonia or carbon injection to control D/F).  **Exemptions f** 

**rom Performance Tests** o **Scrap shredders** that always process clean scrap and don’t generate visible emissions (due to low speed and or oth er parameters) as determined b y EP A Method 22 should be exempt from periodic testing, if not exempt from rule . o **Group 1 furnaces operated <130 o**  **F** (as measured at the inlet and outlet) should be exempted from afterburner testing for dioxin/furans  D/F formati on temperature is >130 oF.EPA - HQ - OAR- 2010 - 0544 - DRAFT - 0203.doc Page 6 of 7

6  **Hood P**  **erform ance Tests**  o Clarify that the volumetric flowrate ENTERING the hood should be used and not the stack exit flow . o Clarify that testing of hood flowrate can be done BEFORE performance test is begun (so can re a djust before testing whole s ys tem) ; need to retest hood after adjustments. o Clarify that must measure actual volumetric flowrate of hood during lowest expected air flow conditions (ambient air damper in most open position).  **Method 22 T**  **esti ng**  o Add allowance for testing in three 20 minute intervals, with greater than 10 minute breaks in between for a total test time of 60 minutes. **5 .**  **Calculations**  **Hoods** o Can only

use high canopy

hood equation if low canopy equation is not appropriate, i.e., where the distance between the hoo d and the hot source is greater than the diameter of the source or greater than 3 feet, which ever is larger.  **Multiple Control Devices:** o Clarify calculations for individual furnaces ducted to a common control device.  **Emissions Calculations to Meet Limits**  **i n**  **Terms of Mass of Product** o [W ould this be useful?

] **6 .**  **C orrect** **ions Where Requirements Are Obsolete o**  **r Erroneous**  **Ventilation System Requirements :**  o Remove ACGIH Ventilation Manual (23 rd edition) that is incorporated b y reference . This manual is no longer available for purchase, is outdated . Also, EPA no longer incorporates non - Agency documents such as operating manuals.  **B ag**  **L eak**  **D etection**  **S ystems (BLDS)**  **R equirements**  **:** o Remove 1997 guidance document on bag leak detection systems. Current BLDS operate digitally , which is not covered in 1997 guidance. o Add requirement that manufacturer’s operating instructions should be followed at all times . **7 .**  **Typographical Corrections**  **§63.1503 Defin itions**  **: Clean Charge** o Replace comma with semicolon before the phrase: “...and runaround scrap , ” as follows:  Clean charge means furnace charge materials, including molten aluminum; T -bar; sow; ingot; billet; pig; alloying elements; aluminum scrap known b y the owner or operator to be entirely free of paints, coatings, and lubricant s; uncoated/unpainted aluminum chips that have been thermall y dried or treated b y a centrifugal cleaner; aluminum scrap dried at 343 °C (650 °F) or higher; aluminum scrap delacquered/ decoated at 482 °C (900 °F) or higher ; and runaround scrap.EPA - HQ - OAR- 2010 - 0544 - DRAFT - 0203.doc Page 7 of 7

7  **§ 63.1505** . **Emission standards for affected sources and emission units ;**  **(k) Secondary aluminum processing**  **.** o Correct E quation 1 legend for T ti = feed/charge rate for individual emission unit I :  Change “ emission unit **I ”**  to “emission unit i **”** to be consistent with other e quations in the rule..  **§ 63.1510(n)(2) .**  **Sidewell group 1 furnace with add -**  **on air pollution control**  **devices** o Change reference citing § 63.1506(m)(7) to §63.1506(m)(6). There is no §63.1506(m)(7) and §63.1506(m)(6) has the right information..