UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460



## AUG 1 8 2006

OFFICE OF ENFORCEMENT AND COMPLIANCE ASSURANCE


### MEMORANDUM SUBJECT:

FROM:

TO: Compliance with American Conference ofGovernmental Industrial Hygienists Ventilation Manual in the Secondary Aluminum Production National Emission Standard for Hazardous AirPtollutaf:.nts



### ~· Michael A. Alushin, Directo Compliance Assessment and dia rograms ivision Office ofCompliance Regional AirDivision Directors (I-X)

The purpose ofthis memorandum is to provide guidance on implementation and compliance monitoring for the Secondary AluminumNational Emission Standardfor Hazardous Air Pollutants (NESHAP) Subpart RRR requirements on capture and collection ofemissions. Several regions have determined that many facilities are not following the required ventilation practices and/ornot providing sufficient information to demonstrate compliance with the requirements in Subpart RRR. The Secondary Aluminum NESHAP adopts by reference chapters 3 and 5 ofthe 

### Industrial Ventilation:A Manualof RecommendedPractice, 23rd edition, published by the Amencan Conference ofGovernmental Industrial Hygienists (ACGIH). As required by Section 63.1506(c) ofSubpart RRR, owners oroperators ofaffected sources oremissions units with addon air pollution control devices must: (1) Design and install a system for the capture and collection of emissions to meet the engineering standards for minimum exhaust rates as publishedby the American Conference ofGovernmental Industrial Hygienists in chapters 3 and 5 of "Industrial Ventilation: A Manual ofRecommendedPractice" (incorporated byreference in §63.1502 ofthis subpart).

Internet Address (URL) • http.//www.epa.gov Recycled/Recyclable • Printed with Vegetable Oil Based Inks on 100% Postconsumer, Process Chlonne Free Recycled Paper2 In addition, Section 63.1515 (b)(5) requires facilities subject to Subpart RRR to provide the following: Design information and analysis, with supporting documentation, demonstrating conformance with the requirements for capture/collection systems in §63.1506(c). Below are specific issues raised by EPA Regional Offices on the capture andcollection of emissions at secondary aluminum facilities followed by EPA headquarters responses.



### Issue 1: 40 CFR Section 63.1515(b)(5) requires facilities to submit a Notification ofCompliance Status Report (NOCSR) within 60 days after the compliance date. The NOCSR must identify the facility's compliance status with the rule requirements, including Chapters 3 and 5 ofthe ACGIH Industrial Ventilation Manual for capture and collection systems. Specifically, the rule requires that the NOCSR include design information and analysis with supporting documentation demonstrating conformance with the capture and collection systems required by Section 63.1506(c). What information must the facility provide to demonstrate compliance with Section 63.1506(c)? 

### Response 1: To demonstrate conformance with the ACGIH minimum volumetric flowrate calculations, the facility must collect actual volumetric tlowrate measurements to compare to the ACGIH calculated tlowrates. Actual tlowrate measurements should be taken in accordance with the methodologies prescribed in EPA Reference Methods 1_9nd 2 (andEPA Reference Methods 3 and 4 ifneeded) which are contained in 40CFR Part 60, Appendix A. The actual tlowrate measurements should be taken at locations in the duct work downstream ofthe furnace hoods which will be representative ofthe actual volumetric tlowrate without the interference ofleaks, the introduction ofambient air for cooling, orotherducts manifolded from other hoods. The measured volumetric tlowrate should reflect what is actually being captured by each hood. In some cases, facilities are using stack gas exit volumetric tlowrates that were determined during a perfmmance test; however, these tlowrates are not necessarily representative ofwhat is actually entering each hood. Generally, facilities should also measure the actual volumetric tlowrate dUiing the lowest expected tlowrate conditions. Forexample, reduced draw at the hoodcan be created when the damper position that introduces ambient air is in the most open position.
In addition, the facility may wish to take the actual volumetric tlowrate measurements immediately priorto the performance test instead ofconducting the measurement and the test at the same time. Taking the actual tlowrate measurement prior to the performance test enables a facility to identify any problems with the capture and collection system before the petformance test, and thus avoid having the performance test be invalidated. This approach is acceptable if the company measures the actual volumetric tlowrate immediately prior to the peri'ormance test,

### 3 andmakes no structural orconfigurationchanges to the capture andcollection system after the measurement andbefore theperformancetest. Designinformation and analysis with supporting documentation demonstrating conformance withthe capture and collection systemrequired by Section 63.1506(c) may be required when any parameteror design configurationchanges occur that could impact the volumetric flowrate.
Issue 2: 40 CFRSection 63.1510(d) requires a source to inspect each capture and collection system at least once each calendaryearto ensurethat each system is operating in accordance with the operatingrequirements in Section 63.1506(c) and to record the results ofeach inspection. How do facilities ensure that they continueto meetthe capture and collectionrequirements? Response 2: To verify that eachcapture and collection system continues to operate in accordance with the minimum volumetric flowrate that is calculated usingthe equations in Chapters 3 and 5 during the annual inspection, the source would need to repeatthe collection ofthe actual volumetric measurements in accordance with the methodologies and locations discussed in Response 1above. Also, the total capture and collection system shouldbeinspected to ensure continued operational integrity (e.g., inspect for eroded ordeteriorated ductwork).
Issue 3: Some facilities haveused the high canopy hood equation in situations where the low canopy hood equation was more appropriate. The facilities have zeroed out the height between the hot source andthe hood while using the high canopy equation. Cana facility usethe high canopy hood equation for all design configurations? Response 3: No. The equation thatmost closely fits the actual design configuration ofthe capture and collection system shouldbe used. Section 3.9.3 in Chapter 3 oftheACGIH Industrial Ventilation Manual states that "ifthe distance between the hood and the hot source does not exceed approximately the diameter ofthe source or 3 feet, whichever is smaller, the hood may be considered a low canopy hood. Therefore, compliance with all ofthe equations in the ACGIH Industrial Ventilation Manual should be enforced as identified in Section 63.1506(c).
Ifyouhave any questions, please contact ScottThrowe ofmy staff(202-564-7013), or Dick Dubose (404-562-9168) orTodd Russo (404-562-9194) ofEPA Region 4, who worked with
our office in drafting this memorandum.

cc: Regional AirEnforcement Managers Dick Dubose, Region4 Todd Russo, Region 4