§63.105. Maintenance wastewater requirements. — Inbound Citations

(b) The owner or operator of each affected source shall comply with the HON maintenance wastewater requirements in § 63.105. When terms used in § 63.105 are defined in § 63.1101, the definition in § 63.1101 shall apply, for the purpose of this subpart. For terms used in § 63.105 that are not defined in § 63.1101, the definitions in §§ 63.101 and 63.111 shall apply.

(e) You must comply with the requirements specified in § 63.105 of subpart F of this part.

(c) For each affected source, the owner or operator shall comply with the requirements for maintenance wastewater in § 63.105, except that when § 63.105(a) refers to “organic HAPs listed in table 9 of subpart G of this part,” the owner or operator is only required to consider compounds that meet the definition of organic HAP in § 63.1312 and that are listed in table 9 of 40 CFR part 63, subpart G, except for ethylene glycol which need not be considered, for the purposes of this subpart.

(b) The owner or operator of each affected source shall comply with the HON maintenance wastewater requirements in § 63.105, with the exceptions noted in paragraphs (b) (1), (2), and (3) of this section.

(1) When the HON maintenance wastewater provisions in § 63.105(a) refer to “organic HAPs listed in Table 9 of subpart G of this part,” the owner or operator is only required to consider compounds that meet the definition of organic HAP in § 63.1423 and that are listed in Table 9 of 40 CFR part 63, subpart G, for the purposes of this subpart.

(2) When the term “maintenance wastewater” is used in the HON maintenance wastewater provisions in § 63.105, the definition of “maintenance wastewater” in § 63.1423 shall apply, for the purposes of this subpart.

(3) When the term “wastewater” is used in the HON maintenance wastewater provisions in § 63.105, the definition of “wastewater” in § 63.1423 shall apply, for the purposes of this subpart.

(b) Where § 63.105 and §§ 63.132 through 63.148 refer to compounds in table 9 of subpart G of this part 63, the compounds in tables 8 and 9 to this subpart apply for the purposes of this subpart.

(f) For an affected source complying with the requirements in §§ 63.104 and 63.105, the terms used in this subpart and in §§ 63.104 and 63.105 of this subpart have the meaning given them in § 63.101, except as specified in §§ 63.2450(m), 63.2490(b), and paragraph (i) of this section.

(b) Except for those streams exempted by paragraphs (c) and (d) of this section, the owner or operator of each affected source shall comply with the requirements for maintenance wastewater in § 63.105, except that when § 63.105(a) refers to “organic HAPs listed in table 9 to subpart G of this part,” the owner or operator is only required to consider compounds that meet the definition of organic HAP in § 63.482 and that are listed in table 9 to subpart G of this part, for the purposes of this subpart.

(c) For each affected source, the owner or operator shall comply with the requirements for maintenance wastewater in § 63.105, except that when § 63.105(a) refers to “organic HAPs listed in table 9 of subpart G of this part,” the owner or operator is only required to consider compounds that meet the definition of organic HAP in § 63.1312 and that are listed in table 9 of 40 CFR part 63, subpart G, except for ethylene glycol which need not be considered, for the purposes of this subpart.

(a) Except as specified in paragraph (c) of this section, the owner or operator of each affected source shall comply with the HON wastewater requirements in §§ 63.132 through 63.147 for each process wastewater stream originating at an affected source, with the HON leak inspection requirements in § 63.148, and with the HON requirements in § 63.149 for equipment that is subject to § 63.149, with the differences noted in paragraphs (a)(1) through (20) of this section and, beginning March 18, 2026, paragraphs (a)(21) through (26) of this section. Further, the owner or operator of each affected source shall comply with the requirements of § 63.105(a) for maintenance wastewater, as specified in paragraph (b) of this section.

(1) Owners and operators of affected sources are not required to comply with the HON new source wastewater requirements in § 63.132(b)(1) and (d) for the purposes of this subpart. Owners or operators of all new affected sources, as defined in this subpart, shall comply with the HON requirements for existing sources in §§ 63.132 through 63.149, with the exceptions noted in paragraphs (a)(2) through (26) of this section.

(2) The provisions of paragraphs (a)(2)(i), (ii), and (a)(10)(iii) of this section clarify the organic HAP that an owner or operator shall consider when complying with the requirements of §§ 63.132 through 63.149.

(i) Owners and operators are exempt from all requirements in §§ 63.132 through 63.149 that pertain solely and exclusively to organic HAP listed on Table 8 of 40 CFR part 63, subpart G.

(ii) When the HON requirements in §§ 63.132 through 63.149 refer to Table 9 compounds, the owner or operator is only required to consider compounds that meet the definition of organic HAP in § 63.1423 and that are listed in Table 9 of 40 CFR part 63, subpart G, for the purposes of this subpart.

(iii) When §§ 63.132 through 63.149 refer to compounds in Table 36 of 40 CFR part 63, subpart G, or compounds in List 1 or List 2 of Table 36 of 40 CFR part 63, subpart G, the owner or operator is only required to consider compounds that meet the definition of organic HAP in § 63.1423 and that are listed on Table 36 of 40 CFR part 63, subpart G, for the purposes of this subpart.

(3) When the determination of equivalence criteria in § 63.102(b) is referred to in §§ 63.132, 63.133, and 63.137, the General Provisions' alternative nonopacity emission standard provisions in § 63.6(g) shall apply for the purposes of this subpart.

(4) When the HON storage vessel requirements contained in §§ 63.119 through 63.123 are referred to in §§ 63.132 through 63.148, the HON storage vessel requirements in §§ 63.119 through 63.123 are applicable, with the exception of the differences referred to in the storage vessel requirements in § 63.1432, for the purposes of this subpart.

(5) When the HON process wastewater reporting requirements in § 63.146(a) require the submission of a request for approval to monitor alternative parameters according to the procedures specified in § 63.151(f) or (g), the owner or operator requesting to monitor alternative parameters shall follow the procedures specified in § 63.1439(f) for the purposes of this subpart.

(6) When the HON process wastewater recordkeeping requirements in § 63.147(d) require the owner or operator to keep records of the daily average value of each continuously monitored parameter for each operating day as specified in the HON recordkeeping provisions in § 63.152(f), the owner or operator shall instead keep records of the daily average value of each continuously monitored parameter as specified in § 63.1439(d), for the purposes of this subpart.

(7) When §§ 63.132 through 63.149 refer to an “existing source,” the term existing affected source, as defined in § 63.1420(a)(2), shall apply for the purposes of this subpart.

(8) When the HON requirements in §§ 63.132 through 63.149 refer to a “new source,” the term new affected source, as defined in § 63.1420(a)(3), shall apply for the purposes of this subpart.

(9) When the HON process wastewater provisions in § 63.132 (a) and (b) refer to the “applicable dates specified in § 63.100 of subpart F of this part,” the applicable compliance dates specified in § 63.1422 shall apply, for the purposes of this subpart.

(10) Whenever the HON process wastewater provisions in §§ 63.132 through 63.147 refer to a Group 1 wastewater stream or a Group 2 wastewater stream, the definitions of these terms contained in § 63.1423 shall apply, for the purposes of this subpart.

(11) When the HON control requirements for certain liquid streams in open systems, in § 63.149(d), refer to “§ 63.100(f) of subpart F,” the phrase “§ 63.1420(c),” shall apply for the purposes of this subpart. In addition, where § 63.149(d) states “and the item of equipment is not otherwise exempt from controls by the provisions of subparts A, F, G, or H of this part,” the phrase “and the item of equipment is not otherwise exempt from controls by the provisions of subparts A, F, G, H, or PPP of this part,” shall apply for the purposes of this subpart.

(12) When the HON control requirements for certain liquid streams in open systems, in § 63.149(e) (1) and (2), refer to “a chemical manufacturing process unit subject to the new source requirements of 40 CFR 63.100(l) (1) or (2),” the phrase “a new affected source as described in § 63.1420(a)(4),” shall apply for the purposes of this subpart.

(13) When the HON Notification of Compliance Status requirements contained in § 63.152(b) are referred to in the HON process wastewater provisions in § 63.138 or § 63.146, the Notification of Compliance Status requirements contained in § 63.1439(e)(5) shall apply for the purposes of this subpart. In addition, when the HON process wastewater provisions in § 63.138 or § 63.146 require that information be reported according to § 63.152(b) in the HON Notification of Compliance Status, owners or operators of affected sources shall report the specified information in the Notification of Compliance Status required by § 63.1439(e)(5), for the purposes of this subpart.

(14) When the HON Periodic Report requirements contained in § 63.152(c) are referred to in the HON process wastewater provisions in § 63.146, the Periodic Report requirements contained in § 63.1439(e)(6) shall apply for the purposes of this subpart. In addition, when § 63.146 requires that information be reported in the HON Periodic Reports required in § 63.152(c), owners or operators of affected sources shall report the specified information in the Periodic Reports required in § 63.1439(e)(6), for the purposes of this subpart.

(15) When the term “range” is used in the HON requirements in §§ 63.132 through 63.149, the term “level” shall be used instead, for the purposes of this subpart. This level shall be determined using the procedures specified in parameter monitoring procedures in § 63.1438.

(16) When the HON process wastewater monitoring and inspection provisions in § 63.143(f) specify that the owner or operator shall establish the range that indicates proper operation of the treatment process or control technique, the owner or operator shall instead comply with the requirements § 63.1438 (c) or (d) for establishing parameter level maximums/minimums, for the purposes of this subpart.

(17) When the HON process wastewater provisions in § 63.146(b) (7) and (8) require that “the information on parameter ranges specified in § 63.152(b)(2)” be reported in the HON Notification of Compliance Status, owners and operators of affected sources are instead required to report the information on parameter levels in the Notification of Compliance Status as specified in § 63.1439(e)(5)(ii), for the purposes of this subpart.

(18) For the purposes of this subpart, the owner or operator is not required to comply with the HON process wastewater emission reduction provisions in § 63.138(g).

(19) When the provisions of HON process wastewater provisions in § 63.139(c)(1)(ii), § 63.145(d)(4), or § 63.145(i)(2) specify that Method 18, 40 CFR part 60, appendix A shall be used, Method 18 or Method 25A, 40 CFR part 60, appendix A may be used for the purposes of this subpart. The use of Method 25A, 40 CFR part 60, appendix A shall comply with paragraphs (a)(19) (i) and (ii) of this section.

(i) The organic HAP used as the calibration gas for Method 25A, 40 CFR part 60, appendix A shall be the single organic HAP representing the largest percent by volume of the emissions.

(ii) The use of Method 25A, 40 CFR part 60, appendix A is acceptable if the response from the high-level calibration gas is at least 20 times the standard deviation of the response from the zero calibration gas when the instrument is zeroed on the most sensitive scale.

(20) The owner or operator of a facility which receives a Group 1 wastewater stream, or a residual removed from a Group 1 wastewater stream, for treatment pursuant to the HON provisions in § 63.132(g) is subject to the requirements of § 63.132(g), with the differences identified in this section, and is not subject to the NESHAP from off-site waste and recovery operations in 40 CFR part 63, subpart DD, with respect to the received material.

(21) Substitute “For each source as defined in § 63.101, beginning no later than the compliance dates specified in § 63.100(k)(10),” with “For each affected source as described in § 63.1420(a), beginning no later than the compliance dates specified in § 63.1422(h),”.

(22) Substitute “pressure relief devices are subject to the requirements specified in § 63.165(e) of subpart H of this part” with “pressure relief devices are subject to the requirements specified in § 63.1434(c)”.

(i) Substitute “For each source as defined in § 63.101, beginning no later than the compliance dates specified in § 63.100(k)(11),” with “For each affected source as described in § 63.1420(a), beginning no later than the compliance dates specified in § 63.1422(h),”.

(ii) Substitute “in ethylene oxide service, as defined in § 63.101” with “in ethylene oxide service, as defined in § 63.1423”.

(iii) § 63.138(b)(3) and (c)(3) do not apply. Instead, for each affected source as described in § 63.1420(a), beginning no later than the compliance dates specified in § 63.1422(h), for Group 1 wastewater streams in ethylene oxide service, you must comply with one of the treatment options specified in paragraph (a)(23)(iii)(A), (B), or (C) of this section in addition to the control device requirements specified in § 63.138(a)(5). Individual wastewater streams may be excluded from this requirement if their combined ethylene oxide load in the wastewater prior to treatment is less than 1.0 megagram per year, provided you comply with paragraph (a)(23)(iii)(D) of this section.

(A) Reduce the concentration of ethylene oxide of each wastewater stream, by removal or destruction, to a level less than 1 ppmw. If you choose to comply with this paragraph (a)(23)(iii)(A) of this section, then you must demonstrate compliance using procedures specified in § 63.145(b), except the parenthetical sentence at the end of § 63.145(b) does not apply, and when “§ 63.138(b)(1) and § 63.138(c)(1)” are referred to in § 63.145(b), it means this paragraph (a)(23)(iii)(A) of this section.

(B) Comply with § 63.138(d). If you choose to comply with this paragraph (a)(23)(iii)(B) of this section, then neither a design evaluation nor a performance test is required in accordance with § 63.145(a)(1).

(C) Comply with § 63.138(e). You may not use a design evaluation as specified in § 63.145(a)(2) to demonstrate compliance with this paragraph (a)(23)(iii)(C) of this section. Instead, to demonstrate compliance with this paragraph (a)(23)(iii)(C) of this section, you must conduct a performance test as specified in § 63.145(c) or (d).

(D) If you exclude individual wastewater streams from compliance with paragraph (a)(23)(iii) of this section based on combined ethylene oxide load prior to treatment, then you must conduct annual sampling of each wastewater stream using the procedures specified in §§ 63.144(b)(5)(i)(I) and 63.145(b), except the parenthetical sentence at the end of § 63.145(b) does not apply and when “§ 63.138(b)(1) and § 63.138(c)(1)” are referred to in § 63.145(b), it means this paragraph (a)(23)(iii)(D) of this section.

(24) Substitute “For each source as defined in § 63.101,” with “For each affected source as described in § 63.1420(a),”.

(25) Substitute “§ 63.108” with “§ 63.1436”.

(26) Substitute “Except for pressure relief devices subject to § 63.165(e)(4),” with “Except for pressure relief devices subject to § 63.1434(c),”.

(a) Except as specified in paragraphs (c) through (f) of this section, the owner or operator of each affected source shall comply with the requirements of §§ 63.132 through 63.147 for each process wastewater stream originating at an affected source, with the requirements of § 63.148 for leak inspection provisions, and with the requirements of § 63.149 for equipment that is subject to § 63.149, with the differences noted in paragraphs (a)(1) through (23) of this section. Further, the owner or operator of each affected source shall comply with the requirements of § 63.105(a) for maintenance wastewater, as specified in paragraph (b) of this section.

(1) When the determination of equivalence criteria in § 63.102(b) is referred to in §§ 63.132, 63.133, and 63.137, the provisions in § 63.6(g) shall apply for the purposes of this subpart.

(2) When the storage vessel requirements contained in §§ 63.119 through 63.123 are referred to in §§ 63.132 through 63.149, §§ 63.119 through 63.123 are applicable, with the exception of the differences referred to in § 63.484, for the purposes of this subpart.

(3) Owners and operators of affected sources are not required to comply with the requirements in § 63.132(b)(1) and § 63.132(d). Owners and operators of new affected sources, as defined in this subpart, shall comply with the requirements for existing sources in §§ 63.132 through 63.149, with the exceptions noted in paragraphs (a)(4), (a)(10), and (a)(23) of this section.

(4) When § 63.146(a) requires the submission of a request for approval to monitor alternative parameters according to the procedures specified in § 63.151(f) or (g), owners or operators requesting to monitor alternative parameters shall follow the procedures specified in § 63.506(f), for the purposes of this subpart.

(5) When § 63.147(d) requires owners or operators to keep records of the daily average value of each continuously monitored parameter for each operating day as specified in § 63.152(f), owners and operators shall instead keep records of the daily average value of each continuously monitored parameter as specified in § 63.506(d), for the purposes of this subpart.

(6) When §§ 63.132 through 63.149 refer to an “existing source,” the term “existing affected source,” as defined in § 63.480(a)(3) shall apply, for the purposes of this subpart.

(7) When §§ 63.132 through 63.149 refer to a “new source,” the term “new affected source,” as defined in § 63.480(a)(4) shall apply, for the purposes of this subpart.

(8) Whenever §§ 63.132 through 63.149 refer to a “chemical manufacturing process unit,” the term “elastomer product process unit,” (or EPPU) as defined in § 63.482, shall apply for the purposes of this subpart. In addition, when § 63.149 refers to “a chemical manufacturing process unit that meets the criteria of § 63.100(b) of subpart F of this part,” the term “an EPPU as defined in § 63.482(b)” shall apply for the purposes of this subpart.

(9) When § 63.132(a) and (b) refer to the “applicable dates specified in § 63.100 of subpart F of this part,” the compliance dates specified in § 63.481 shall apply, for the purposes of this subpart.

(10) The provisions of paragraphs (a)(10)(i) through (iv) of this section clarify the organic HAP that an owner or operator must consider when complying with the requirements of §§ 63.132 through 63.149.

(i) Owners and operators are exempt from all requirements in §§ 63.132 through 63.149 that pertain solely and exclusively to organic HAP listed on table 8 to 40 CFR part 63, subpart G.

(ii) When §§ 63.132 through 63.149 refer to table 9 compounds, the owner or operator is only required to consider compounds that meet the definition of organic HAP in § 63.482 and that are listed in table 9 to 40 CFR part 63, subpart G, for the purposes of this subpart.

(iii) When §§ 63.132 through 63.149 refer to compounds in table 36 to 40 CFR part 63, subpart G, or compounds in List 1 and/or List 2, as listed in table 36 to 40 CFR part 63, subpart G, the owner or operator is only required to consider compounds that meet the definition of organic HAP in § 63.482 and that are listed in table 36 to 40 CFR part 63, subpart G, for the purposes of this subpart.

(iv) For each affected source as described in § 63.480, beginning no later than the compliance dates specified in § 63.481(o), the provisions specified in § 63.132(c)(1)(iii) do not apply. Instead, if the wastewater stream contains chloroprene such that it is considered to be in chloroprene service, as defined in § 63.482, then the wastewater stream is a Group 1 wastewater stream. For wastewater streams in chloroprene service, owners and operators must also meet the requirements specified in § 63.510.

(11) Whenever §§ 63.132 through 63.147 refer to a Group 1 wastewater stream or a Group 2 wastewater stream, the definitions of these terms contained in § 63.482 shall apply, for the purposes of this subpart.

(12) When § 63.149(d) refers to “§ 63.100(f) of subpart F” the phrase “§ 63.480(c)” shall apply for the purposes of this subpart. In addition, where § 63.149(d) states “and the item of equipment is not otherwise exempt from controls by the provisions of subparts A, F, G, or H of this part”, the phrase “and the item of equipment is not otherwise exempt from controls by the provisions of subparts A, F, G, H, or U of this part,” shall apply for the purposes of this subpart.

(13) When § 63.149(e)(1) and (e)(2) refer to “a chemical manufacturing process unit subject to the new source requirements of 40 CFR 63.100(l)(1) or 40 CFR 63.100 (l)(2),” the phrase “an EPPU that is part of a new affected source or that is a new affected source,” shall apply for the purposes of this subpart.

(14) When the Notification of Compliance Status requirements contained in § 63.152(b) are referred to in §§ 63.138 and 63.146, the Notification of Compliance Status requirements contained in § 63.506(e)(5) shall apply for the purposes of this subpart. In addition, when §§ 63.138 and 63.146 require that information be reported according to § 63.152(b) in the Notification of Compliance Status, owners or operators of affected sources shall report the specified information in the Notification of Compliance Status required by § 63.506(e)(5), for the purposes of this subpart.

(15) When the Periodic Report requirements contained in § 63.152(c) are referred to in § 63.146, the Periodic Report requirements contained in § 63.506(e)(6) shall apply for the purposes of this subpart. In addition, when § 63.146 requires that information be reported in the Periodic Reports required in § 63.152(c), owners or operators of affected sources shall report the specified information in the Periodic Reports required in § 63.506(e)(6), for the purposes of this subpart.

(16) When the term “range” is used in §§ 63.132 through 63.149, the term “level” shall apply instead, for the purposes of this subpart. This level shall be determined using the procedures specified in § 63.505.

(17) When § 63.143(f) specifies that owners or operators shall establish the range that indicates proper operation of the treatment process or control device, the owner or operator shall instead comply with the requirements of § 63.505(c) or (d) for establishing parameter level maximums/minimums, for the purposes of this subpart.

(18) When § 63.146(b)(7) and § 63.146(b)(8) require that “the information on parameter ranges specified in § 63.152(b)(2)” be reported in the Notification of Compliance Status, owners and operators of affected sources are instead required to report the information on parameter levels in the Notification of Compliance Status as specified in § 63.506(e)(5)(ii), for the purposes of this subpart.

(19) For the purposes of this subpart, the owner or operator of an affected source is not required to include process wastewater streams that contain styrene when conducting performance tests for the purposes of calculating the required mass removal (RMR) or the actual mass removal (AMR) under the provisions described in § 63.145(f) or § 63.145(g). For purposes of this paragraph, a process wastewater stream is considered to contain styrene if the wastewater stream meets the requirements in paragraph (a)(19)(i), (ii), or (iii) of this section:

(i) The wastewater stream originates at equipment that produces styrene butadiene rubber by solution;

(ii) The wastewater stream originates at equipment that produces styrene butadiene rubber by emulsion; or

(20) When the provisions of § 63.139(c)(1)(ii), § 63.145(d)(4), or § 63.145(i)(2) specify that Method 18 of appendix A-6 to 40 CFR part 60 must be used, Method 18 or Method 25A of appendices A-6 and A-7 to 40 CFR part 60, respectively, may be used for the purposes of this subpart. ASTM D6420-18 (incorporated by reference, see § 63.14) may also be used in lieu of Method 18, if the target compounds are all known and are all listed in Section 1.1 of ASTM D6420-18 as measurable; ASTM D6420-18 must not be used for methane and ethane; and ASTM D6420-18 may not be used as a total VOC method. The use of Method 25A must conform with the requirements in paragraphs (a)(20)(i) and (ii) of this section.

(i) The organic HAP used as the calibration gas for Method 25A of appendix A-7 to 40 CFR part 60 must be the single organic HAP representing the largest percent by volume of the emissions.

(ii) The use of Method 25A of appendix A-7 to 40 CFR part 60 is acceptable if the response from the high-level calibration gas is at least 20 times the standard deviation of the response from the zero calibration gas when the instrument is zeroed on the most sensitive scale.

(21) In § 63.145(j), instead of the reference to § 63.11(b), and instead of § 63.145(j)(1) and § 63.145(j)(2), the requirements in § 63.504(c) shall apply.

(22) The owner or operator of a facility which receives a Group 1 wastewater stream, or a residual removed from a Group 1 wastewater stream, for treatment pursuant to § 63.132(g) is subject to the requirements of § 63.132(g) with the differences identified in this section, and is not subject to subpart DD of this part, with respect to the received material.

(23) When § 63.132(g) refers to “§§ 63.133 through 63.137” or “§§ 63.133 through 63.147”, the provisions in this § 63.501 shall apply, for the purposes of this subpart.

(a) Each owner or operator of a source subject to this subpart shall comply with the requirements of paragraphs (b) through (e) of this section for maintenance wastewaters containing those organic HAP's listed in table 9 of subpart G of this part.

(a) Each owner or operator of a source subject to this subpart shall comply with the requirements of paragraphs (b) through (e) of this section for maintenance wastewaters containing those organic HAP's listed in table 9 of subpart G of this part.

(a) Each owner or operator of a source subject to this subpart shall comply with the requirements of paragraphs (b) through (e) of this section for maintenance wastewaters containing those organic HAP's listed in table 9 of subpart G of this part.

(1) Section 63.105(d) of subpart F and the phrase “as part of the start-up, shutdown, and malfunction plan required under § 63.6(e)(3) of subpart A of this part” from § 63.105(e) of subpart F.

(a) Each owner or operator of a source subject to this subpart shall comply with the requirements of paragraphs (b) through (e) of this section for maintenance wastewaters containing those organic HAP's listed in table 9 of subpart G of this part.

(1) Section 63.105(d) of subpart F and the phrase “as part of the start-up, shutdown, and malfunction plan required under § 63.6(e)(3) of subpart A of this part” from § 63.105(e) of subpart F.

(1) Connectors subject to the provisions of § 65.105(e) may be designated unsafe to repair if the owner or operator determines that repair personnel would be exposed to an immediate danger as a consequence of complying with the repair requirements of this subpart, and if the connector will be repaired before the end of the next process unit shutdown as specified in § 63.105(e).