David Shanks
7 October 2013

The Aerospace CTG of 1997 was patterned after the Aerospace NESHAP of 1995.  Its numerical VOC emission limits were based on organic HAP limits in the NESHAP.   The CTG scope of coverage, exemptions, housekeeping provisions, and solvent vapor pressure limits mirror the organic HAP control measures in the NESHAP.  The major difference is that the Aerospace CTG determined RACT VOC limits for specialty coatings, while the NESHAP excluded specialty coatings, due to low usage.  Also, the NESHAP contains control measures for inorganic HAP, which is outside the scope of the CTG for VOCs. 

The Aerospace NESHAP contains the following exemption in the overall rule Applicability section (40 CFR 63.741(e)):

      "All wastes that are determined to be hazardous wastes under the Resource Conservation and Recovery Act of 1976 (PL 94-580) (RCRA) as implemented by 40 CFR parts 260 and 261, and that are subject to RCRA requirements as implemented in 40 CFR part 262 through 268, are exempt from the requirements of this subpart."  

The corresponding Applicability sections in the Missouri Aerospace VOC rules are 10 CSR 10-5.295(3)(I) for St. Louis and 10 CSR 10-2.205(3)(I) for Kansas City, but the RCRA waste exemption is absent from these VOC rules.    I've reviewed the earliest drafts of the St. Louis aerospace VOC rule.  In the first rule proposal, Section (3)(I) followed the NESHAP exemptions in all respects except the RCRA waste exemption.   I gave oral testimony at the Sept. 23, 1999 public hearing, but I didn't address the RCRA waste exemption in my comments, because I didn't notice the discrepancy.  

The purpose of the RCRA exemption in the NESHAP is to avoid having the "closed container" housekeeping requirement for Cleaning Operations in the NESHAP (63.744) carry over into an identical "closed container" requirement once the cleaning materials enter hazardous waste rule jurisdiction.   Once a solvent wipe or spent solvent is placed in a RCRA waste container, the RCRA rules require the container to be kept closed in the shop area where it was generated ("satellite accumulation area"), during transport to an on-site storage area, during storage, during transportation to an off-site facility (i.e. beyond the jurisdiction of the aerospace NESHAP or aerospace VOC rules), and while it is awaiting final treatment or disposal at an off-site facility. 

Unlike the NESHAP, the Cleaning Operation housekeeping sections of Missouri VOC rules 10 CSR  10-5.295(3)(E) and 10 CSR 10-2.205(3)(E) overlap hazardous waste requirements.    To eliminate this overlap in the Missouri rules, I suggest placing RCRA waste exemptions at the end of Section (3)(I) of the St. Louis and Kansas City rules.  However, the RCRA exemption language in the NESHAP (above) is unnecessarily complex.      A more concise Missouri-specific  exemption  would be:

      "17.  All wastes that are determined to be hazardous waste under Missouri hazardous waste regulation 10 CSR 25-4.261, and that are subject to the hazardous waste generators standards of 10 CSR 25-5.262." 

Recently, the federal hazardous waste rules have been modified for solvent-contaminated wipes that may be used in some aerospace cleaning operations.   Under this rule, certain solvent wipes are conditionally excluded from the full range of hazardous waste rules, so long as they are managed under specific conditions.  One of the conditions of this solvent wipe rule is a closed container requirement: 
 
      "The solvent-contaminated wipes, when accumulated, stored, and transported, are contained in non-leaking closed containers that are labeled `Excluded Solvent-Contaminated Wipes.'  The containers must be able to contain free liquids, should free liquids occur.  During accumulation, a container is considered closed when there is complete contact between the fitted lid and the rim, except when it is necessary to add or removed solvent-contaminated wipes.  When the container is full, or when the solvent-contaminated wipes are no longer being accumulated, or when the container is being transported, the container must be sealed with all the lids properly and securely affixed to the container and all openings tightly bound or closed sufficiently to prevent leaks and emissions."  
      
The federal solvent-contaminated wipe rule is not effective in most states (including Missouri) until it is incorporated into state hazardous waste rules.  Florida proposed to do so on October 1, and the solvent wipe rule is being discussed as a potential near-term incorporation at Missouri DNR Hazardous Waste Advisory Forum meetings.  It is not yet in Missouri rule, however, so the exemption suggested below cites the federal rule and a trigger based on Missouri adoption:   

      "18.  Solvent-contaminated wipes that are managed in accordance with the conditional exclusions of 40 CFR 261.4(a)(26) or (b)(18), if incorporated into Missouri hazardous waste regulations. "      


