Response to comments on 1121 submittal

Comment 1 : It is unclear if RI used the most current final rule entitles "Hazardous Air Pollutants: Amendments to the Approval of State Programs and Delegation of Federal Authorities," dated September 14, 2000 in preparing your package. It appears that RI used an earlier version of this regulation. Please update the citations to reflect the September 2000 regulation. Response: The citations in the submittal have been updated to reflect the September 2000 version. Comment 2: It is unclear if RI used the most recent version of the Halogenated Solvent NESHAP in preparing your package. There was an amendment to this NESHAP on December 3, 1999 (64FR67801) that pertained to continuous web solvent cleaning machines (see enclosed) . Thus it appears that the following sections of the NESHAP were not addressed in RI's equivalency request : 63.469(g), 63.463(e)(2)(ix), (x), (xi), 63.463 (g)(h), 63.465 (f), (g), (h) and 63.467(a)(6)(7) : RI must access these sections for equivalency before EPA can make a final decision. Response: Currently there are no continuous web-cleaning machines in the state. If a continuous web-cleaning machine were to locate in the state they would first be required to obtain a preconstruction permit . Since section 9.3.3(a)(5) of RI Air Pollution Control Regulation No. 9, "Air Pollution Control Permits," requires sources to be in compliance with all applicable state and federal air pollution control regulations, the permit would contain the requirements in the NESHAP. Comment : Regulation No 36 disallows the use of reduced roomdraft as a control option. Although it does make RI's rule more stringent and less flexible fromthe EPA perspective, we do not agree with your reason for denying this option, i .e., the potential for this practice to dramatically increase worker solvent exposure. The worker exposure issue was brought up during rule development to which EPA responded that installation and proper operation of our control combinations would reduce worker exposure. This is especially true for reduced roomdraft since with this technique the solvent vapor layer is less disturbed, therefore reducing vapor emissions, hence reducing worker exposure. Please provide additional clarification regarding your perspective on this issue. Response: While it is possible that, in some cases, reduced roomdraft may reduce worker exposure, there is also the potential for increased worker exposure under some conditions. Since many of the Rhode Island sources covered by this regulation are small and do not have sophisticated technical staff, RI DEM judged that the potential for problems was sufficient that it was preferable to not include this control option. Note that the RI regulation does notdisallowthe use of reduced roomdrafts -- it only disallows the use of reduced

roomdrafts as a control option for compliance with this regulation. Comment : Please clarify the following on page 18 of the General Information document ; it is not clear whether RI regulations require sources to determine a dwell time or whether the regulations defer to the degreaser NESHAP. Response: Sections 36.9, 36.10 and 36.11 of the RI regulation include the requirements for dwell as follows: 36.9 .6 1fdwell or a superheated vaporsystemis used, the . actual dtivell time shall not exceed the rrrirtimurrt dwell time. Minimumandactual dwell time shall be determined using thefollowing procedztres: (a) For units without cr superheated vaporsysterrl, the rrrirtimurn dwell time shall he determined,for each part type or parts basket orfor' the most conrpleti part ty pe or parts basket using thefollowing procedure: (1)

(h) 

### rc) Determine the amount oftime necessar7~for the part or- parts

basket to cease dripping once placed in the vapor zone. The part or parts basket itsedfr this determination must be at, roora7 temperature when placed in the vapor zone; and (2) The n7irriruurrr dwell time required./bi-parts to remain in the fi-eeboard zone above the vapor zone is calculated as 35percent of the tirne determined in Paragraph (a)(1) ofthis subsection.. The minimumdwell time,fora cleaning machine equipped with a superheated vaporstistern shall he detennined according to the specifications of~the rncrnufiwturer ofthe control equipment; and On . a monthly hczsis, the actual dtivell time that parts are held in the fi-eehoarcl zone above the vapor zone shall be measured,- and (a') Ifthe actual dwell time is less than the rninimurn dwell time determined Using the applicable procedure in Paragraph (a) or- (h) qfthis subsection

,fbr~ a particular part

. or parts basket

., the automaticparts handlings~vstem must he ucljtcstecl so~ that this specification is met. 36.111.1 The owner or operator of'a batch vapor or in-line organic cleaning machine shall maintain thef'ollowing recor{ls fr the lifE :tirrre ofthe cleaning unit : (a') lfclivell or superheated vapor is used, the rnirrinrurn dwell times determined i1sing the procedures specified in Paragraph (a) or (b) c?fSubsection 36 . 9.6: and3G.1 tJ .37hc owner or operator ofcr batch vapor or in-line orgpnic cleaning machine shall maintain t

.he,follotiving records, fir ci period, offiveYears: (h) Resulls of~monitoring required under Section 36.9; and Comment : On page 7 of the General Information document there is a list of de minimis levels for apparent applicability to the RI regulations. The list includes 1,1,1 trichloroethane with a permit threshold of 10 Ib/hour. Ten Ibs./hour could potentially be 43 plus tons per year of emissions. This is well over the HAP major source threshold and this provisions seems to allowsources emitting less than the 10 Ibs/hour threshold to be exempt fromthe degreaser regulations. Potentially some sources could get out of the RI rules that should not . However the next paragraph appears to close the exemption. Which provision applies or do they supercede each other. Response: Under the revised "Hazardous Air Pollutants: Amendments to the Approval of State Programs and Delegation of Federal Authorities," dated September 14, 2000 this section is no longer included and is not included in this submittal . However in response to the comment the de minimis levels pertain to permitting of sources, not to applicability to the degreaser regulation. Further, the permitting threshold for 1,1,1-trichloroethane (methyl chloroform) in APC Regulation No. 9, the permitting regulation, was altered effective April 2004 to be 4,000 pounds per year . Since there is no small source exemption in Regulation No. 36, the degreasing regulation ,all degreasing sources are subject to that regulation. Comment : On page 1 of the side by side comparison table, RI says that Regulation No. 36 does not include all of the part 63 general provisions. Many of the general provisions apply to the federal degreaser rule. As a result we cannot make a determination until we know whether RI's regulations and requirements address the general provisions that apply to the degreaser rule. Response: Please see the attached table for a comparison of the RI rule to the General Provisions. Comment : Please provide the definition of new source. Also please clarify whether there are any differences in the control requirements between new and existing sources in the RI rule. Response: The term "new source" is not used in the regulation. The regulation will not be modified to include a definition for new source. The regulation contains compliance schedules for sources that commenced construction or reconstruction prior to November 29, 1993 and sources that commenced construction or reconstruction on or after November 29, 1993.Options for control combinations for in-line cleaning operations differ for new and existing sources . Specifically Sections 36.7.7 and 36.7.8 belowcontain requirements for in line machines installed prior to November 29, 1993 and requirements for in line machines installed on or after November 29, 1993. 36 . 7.7 Any in-line cleaning machine installed before November 29, 9993 must be equipped with one of the following control combinations: (a) Refrigerated freeboard chiller and freeboard ratio of at least 1 .0 ; or (b) Refrigerated freeboard chiller and dwell ; or (c) Carbon adsorber and dwell ; or (d) Another system of equivalent control systemthat is approved by the Director and the EPA. Requests for equivalency determinations must be submitted no later than June 3, 9996 . Requests shall include the following information: (1) A complete description of process and control equipment; (2) Testing procedures that will be used to demonstrate equivalency; and (3) The date, time and location of the equivalency test. 36.7.8 Any in-line cleaning machine installed on or after November 29, 9993 must be equipped with and operate one of the following control combinations: (a) Refrigerated freeboard chiller and a superheated vapor system ; or (b) Refrigerated freeboard chiller and carbon adsorber; or (c) Another systemof equivalent control that is approved by the Director and the EPA. Requests for equivalency determinations for control of cleaning machines installed on or after November 29, 1993 must be submitted and approved prior to startup of the cleaning machine. Requests shall include the following information: (1) A complete description of process and control equipment; (2) Testing procedures that will be used to demonstrate equivalency

; and (3) The date, time and location of the equivalency test.