40 C.F.R. §§ 63.2455–63.2490

You must determine the flowrate of gas (or volume of gas), partial pressures of condensables, temperature (T), and HAP molecular weight (MWHAP) at the exit temperature and exit pressure conditions of the condenser or at the conditions of the dedicated receiver.

You must assume that all of the components contained in the condenser exit vent stream are in equilibrium with the same components in the exit condensate stream (except for noncondensables).

You must perform a material balance for each component.

For the emissions from gas evolution, the term for time, t, must be used in Equation 12 to 40 CFR part 63, subpart GGG.

Emissions from empty vessel purging shall be calculated using Equation 36 to 40 CFR part 63, subpart GGG and the exit temperature and exit pressure conditions of the condenser or the conditions of the dedicated receiver.

You must conduct an engineering assessment as specified in § 63.1257(d)(2)(ii) for each emission episode that is not due to vapor displacement, purging, heating, depressurization, vacuum operations, gas evolution, air drying, or empty vessel purging. The requirements of paragraphs (b)(3) through (4) of this section shall apply.

You may elect to conduct an engineering assessment if you can demonstrate to the Administrator that the methods in § 63.1257(d)(3)(i)(B) are not appropriate.

If you comply with the alternative standard specified in § 63.2505.

If all Group 1 batch process vents within a process are controlled; you conduct the performance test under hypothetical worst case conditions, as defined in § 63.1257(b)(8)(i)(B); and the emission profile is based on capture and control system limitations as specified in § 63.1257(b)(8)(ii)(C).

If you comply with an emission limit using a flare that meets the requirements specified in § 63.987 or § 63.2450(e)(5), as applicable.

You may switch at any time after operating as Group 2 for at least 1 year so that you can show compliance with the 10,000 pounds per year (lb/yr) threshold for Group 2 batch process vents for at least 365 days before the switch. You may elect to start keeping records of emissions from Group 2 batch process vents before the compliance date. Report a switch based on this provision in your next compliance report in accordance with § 63.2520(e)(10)(i).

If the conditions in paragraph (b)(6)(i) of this section are not applicable, you must provide a 60-day advance notice in accordance with § 63.2520(e)(10)(ii) before switching.

The operating limits may be based on the results of the performance test and supplementary information such as engineering assessments and manufacturer's recommendations. These limits may be established for conditions as unique as individual emission episodes for a batch process. You must provide rationale in the precompliance report for the specific level for each operating limit, including any data and calculations used to develop the limit and a description of why the limit indicates proper operation of the control device. The procedures provided in this paragraph (c)(3)(i) have not been approved by the Administrator and determination of the operating limit using these procedures is subject to review and approval by the Administrator.

If you elect to establish separate monitoring levels for different emission episodes within a batch process, you must maintain records in your daily schedule or log of processes indicating each point at which you change from one operating limit to another, even if the duration of the monitoring for an operating limit is less than 15 minutes. You must maintain a daily schedule or log of processes according to § 63.2525(c).

Operational requirements. The biofilter must be operated at all times when emissions are vented to it.

Performance tests. To demonstrate initial compliance, you must conduct a performance test according to the procedures in §§ 63.2450(g) and 63.997 of subpart SS, and paragraphs (c)(9)(ii)(A) through (D) of this section. The design evaluation option for small control devices is not applicable if you use a biofilter.

Monitoring requirements. Use either a biofilter bed temperature monitoring device (or multiple devices) capable of providing a continuous record or an organic monitoring device capable of providing a continuous record. Comply with the requirements in § 63.2450(e)(4), the general requirements for monitoring in § 63.996, and keep records of temperature or other parameter monitoring results as specified in § 63.998(b) and (c), as applicable. If you monitor temperature, the operating temperature range must be based on only the temperatures measured during the performance test; these data may not be supplemented by engineering assessments or manufacturer's recommendations as otherwise allowed in § 63.999(b)(3)(ii)(A). If you establish the operating range (minimum and maximum temperatures) using data from previous performance tests in accordance with § 63.996(c)(6), replacement of the biofilter media with the same type of media is not considered a process change under § 63.997(b)(1). You may expand your biofilter bed temperature operating range by conducting a repeat performance test that demonstrates compliance with the 95-percent reduction requirement or outlet concentration limit, as applicable.

Repeat performance tests. You must conduct a repeat performance test using the applicable methods specified in §§ 63.2450(g) and 63.997 within 2 years following the previous performance test and within 150 days after each replacement of any portion of the biofilter bed media with a different type of media or each replacement of more than 50 percent (by volume) of the biofilter bed media with the same type of media.

The reporting requirements in § 63.2520 do not apply to the owner or operator of the offsite cleaning or reloading facility.

As an alternative to complying with the monitoring, recordkeeping, and reporting provisions in §§ 63.2445 through 63.2550, the owner or operator of an offsite cleaning or reloading facility may comply as specified in § 63.2535(a)(2) with any other subpart of this part 63 which has monitoring, recordkeeping, and reporting provisions as specified in § 63.2535(a)(2).

When § 63.1253(f)(2) refers to pressure testing certifications, the requirements in 40 CFR 61.304(f) apply for barges.

[Reserved]

If the pressure relief device does not consist of or include a rupture disk, conduct instrument monitoring, as specified in § 63.1023(b) of subpart UU, § 63.180(c) of subpart H, or § 65.104(b) of this chapter, no later than 5 calendar days after the pressure relief device returns to organic HAP gas or vapor service following a pressure release to verify that the pressure relief device is operating with an instrument reading of less than 500 ppm.

If the pressure relief device includes a rupture disk, either comply with the requirements in paragraph (e)(2)(i) of this section (and do not replace the rupture disk) or install a replacement disk as soon as practicable after a pressure release, but no later than 5 calendar days after the pressure release.

If the pressure relief device consists only of a rupture disk, install a replacement disk as soon as practicable after a pressure release, but no later than 5 calendar days after the pressure release. You must not initiate startup of the equipment served by the rupture disk until the rupture disc is replaced.

You must equip each affected pressure relief device with a device(s) or use a monitoring system that is capable of:

You must apply at least three redundant prevention measures to each affected pressure relief device and document these measures. Examples of prevention measures include:

If any affected pressure relief device releases to atmosphere as a result of a pressure release event, you must perform root cause analysis and corrective action analysis according to the requirement in paragraph (e)(6) of this section and implement corrective actions according to the requirements in paragraph (e)(7) of this section. You must also calculate the quantity of organic HAP released during each pressure release event and report this quantity as required in § 63.2520(e)(15). Calculations may be based on data from the pressure relief device monitoring alone or in combination with process parameter monitoring data and process knowledge.

You must determine the total number of release events that occurred during the calendar year for each affected pressure relief device separately. Prior to June 3, 2024, you must also determine the total number of release events for each pressure relief device for which the root cause analysis concluded that the root cause was a force majeure event, as defined in § 63.2550.

Except for pressure relief devices described in paragraphs (e)(4) and (5) of this section, the following release events from an affected pressure relief device are a deviation of the pressure release management work practice standards.

Pressure relief devices in heavy liquid service, as defined in § 63.1020 of subpart UU or § 65.103(f) of this chapter.

Pilot-operated pressure relief devices where the primary release valve is routed through a closed vent system to a control device or back into the process, to the fuel gas system, or to a drain system.

Balanced bellows pressure relief devices where the primary release valve is routed through a closed vent system to a control device or back into the process, to the fuel gas system, or to a drain system.

You may conduct a single root cause analysis and corrective action analysis for a single emergency event that causes two or more pressure relief devices installed on the same equipment to release.

Prior to June 3, 2024, you may conduct a single root cause analysis and corrective action analysis for a single emergency event that causes two or more pressure relief devices to release, regardless of the equipment served, if the root cause is reasonably expected to be a force majeure event, as defined in § 63.2550.

Except as provided in paragraphs (e)(6)(i) and (ii) of this section, if more than one pressure relief device has a release during the same time period, an initial root cause analysis must be conducted separately for each pressure relief device that had a release. If the initial root cause analysis indicates that the release events have the same root cause(s), the initially separate root cause analyses may be recorded as a single root cause analysis and a single corrective action analysis may be conducted.

All corrective action(s) must be implemented within 45 days of the event for which the root cause and corrective action analyses were required or as soon thereafter as practicable. If you conclude that no corrective action should be implemented, you must record and explain the basis for that conclusion no later than 45 days following the event.

For corrective actions that cannot be fully implemented within 45 days following the event for which the root cause and corrective action analyses were required, you must develop an implementation schedule to complete the corrective action(s) as soon as practicable.

No later than 45 days following the event for which a root cause and corrective action analyses were required, you must record the corrective action(s) completed to date, and, for action(s) not already completed, a schedule for implementation, including proposed commencement and completion dates.

Section 63.172(d) of subpart H;

Section 63.180(e) of subpart H;

Section 63.181(g)(1)(iii) of subpart H;

The phrase “including periods when a flare pilot light system does not have a flame” from § 63.181(g)(2)(i) of subpart H;

Section 63.1034(b)(2)(iii) of subpart UU; and

Section 65.115(b)(2) of this chapter.

In the introductory text of § 63.180(c), replace the reference to § 63.165(a) with § 63.2480(e)(1).

In § 63.181(b)(2)(i), replace the reference to § 63.165(c) with § 63.2480(e)(4).

In § 63.181(b)(3)(i), replace the reference to § 63.165(a) with § 63.2480(e)(1).

In § 63.181(b)(3)(ii), replace the reference to § 63.165(d) with § 63.2480(e)(2)(ii) and (iii).

In § 63.181(f), replace the reference to § 63.165(a) and (b) with § 63.2480(e)(1) and (2).

The information in § 63.165(a) required to be reported under § 63.182(d)(2)(xiv) is now required to be reported under § 63.2520(e)(15)(i) through (iii).

The reference to § 63.1030(b) in § 63.1021(a) no longer applies.

In § 63.1022(b)(2), replace the reference to § 63.1030(d) with § 63.2480(e)(4).

In § 63.1022(b)(3), replace the reference to § 63.1030(e) with § 63.2480(e)(2)(ii).

The reference to § 63.1030(c) in § 63.1023(a)(1)(v) no longer applies. Instead comply with the § 63.2480(e)(1) and (2).

In § 63.1023(c) introductory text and (c)(4), replace the reference to § 63.1030(b) with § 63.2480(e)(1).

In § 63.1038(c) replace the reference to § 63.1030(c)(3) with § 63.2480(e)(2).

The information in § 63.1030(b) required to be reported under § 63.1039(b)(4) is now required to be reported under § 63.2520(e)(15)(i) and (ii).

The reference to § 65.111(b) of this chapter in § 65.102(a) of this chapter no longer applies.

In § 65.103(b)(3) of this chapter, replace the reference to § 65.111(d) with § 63.2480(e)(4).

In § 65.103(b)(4) of this chapter, replace the reference to § 63.111(e) with § 63.2480(e)(2)(ii).

The reference to § 65.111(b) and (c) of this chapter in § 65.104(a)(1)(iv) of this chapter no longer applies. Instead comply with § 63.2480(e)(1) and (2).

In § 65.104(c) introductory text and (c)(4) of this chapter, replace the reference to § 63.111(b) with § 63.2480(e)(1).

In § 65.119(c)(5) of this chapter, replace the reference to § 65.111(c)(3) with § 63.2480(e)(2) and replace the reference to § 65.111(e) with § 63.2480(e)(2)(ii) and (iii).

The information required to be reported under § 65.120(b)(4) of this chapter is now required to be reported under § 63.2520(e)(15)(i) and (ii).

Include all PSHAP and SHAP compounds in both Group 1 and Group 2 wastewater streams from all MCPU, except you may exclude any compounds that meet the criteria specified in § 63.145(a)(6)(ii) or (iii).

Except as specified in paragraph (n)(2)(vii) of this section, conduct the demonstration under representative process unit and treatment unit operating conditions in accordance with § 63.145(a)(3) and (4).

Determine PSHAP and SHAP concentrations and the total wastewater flow rate at the inlet to the equalization unit in accordance with § 63.145(f)(1) and (2). References in § 63.145(f)(1) and (2) to required mass removal and actual mass removal do not apply for the purposes of this section.

Determine Fbio for the activated sludge unit as specified in § 63.145(h), except as specified in paragraph (n)(2)(iv)(A) or paragraph (n)(2)(iv)(B) of this section.

Determine QMGe, QMGn, and QMGc using EPA's WATER9 model or the most recent update to this model, and conduct testing or use other procedures to validate the modeling results.

Submit the data and results of your demonstration, including both a description of and the results of your WATER9 modeling validation procedures, in your notification of compliance status report as specified in § 63.2520(d)(2)(ii).

Beginning no later than the compliance dates specified in § 63.2445(g), the requirement of § 63.145(a)(3) no longer applies. Instead, you must comply with the conditions specified in § 63.2450(g)(6).

Section 63.139(c)(3) of subpart G;

Section 63.139(d)(3) of subpart G;

Section 63.145(j) of subpart G;

Section 63.146(b)(7)(i) of subpart G; and

Section 63.147(d)(1) of subpart G.

Monitoring locations for closed-loop recirculation heat exchange systems. For each closed loop recirculating heat exchange system, you must collect and analyze a sample from the location(s) described in either paragraph (d)(1)(i)(A) or (B) of this section.

Monitoring locations for once-through heat exchange systems. For each once-through heat exchange system, you must collect and analyze a sample from the location(s) described in paragraph (d)(1)(ii)(A) of this section. You may also elect to collect and analyze an additional sample from the location(s) described in paragraph (d)(1)(ii)(B) of this section.

Monitoring method. If you comply with the total strippable hydrocarbon concentration leak action level as specified in paragraph (d)(1)(iv) of this section, you must comply with the requirements in paragraph (d)(1)(iii)(A) of this section. If you comply with the total hydrocarbon mass emissions rate leak action level as specified in paragraph (d)(1)(iv) of this section, you must comply with the requirements in paragraphs (d)(1)(iii)(A) and (B) of this section.

Monitoring frequency and leak action level. For each heat exchange system, you must initially monitor monthly for 6-months beginning upon startup and monitor quarterly thereafter using a leak action level defined as a total strippable hydrocarbon concentration (as methane) in the stripping gas of 6.2 ppmv or, for heat exchange systems with a recirculation rate of 10,000 gallons per minute or less, you may monitor quarterly using a leak action level defined as a total hydrocarbon mass emissions rate from the heat exchange system (as methane) of 0.18 kg/hr. If a leak is detected as specified in paragraph (d)(1)(v) of this section, then you must monitor monthly until the leak has been repaired according to the requirements in paragraph (d)(2) or (3) of this section. Once the leak has been repaired according to the requirements in paragraph (d)(2) or (3) of this section, quarterly monitoring for the heat exchange system may resume. The monitoring frequencies specified in this paragraph (d)(1)(iv) also apply to the inlet water feed line for a once-through heat exchange system, if monitoring of the inlet water feed is elected as provided in paragraph (d)(1)(ii)(B) of this section.

Leak definition. A leak is defined as described in paragraph (d)(1)(v)(A) or (B) of this section, as applicable.

Physical modifications to the leaking heat exchanger, such as welding the leak or replacing a tube;

Blocking the leaking tube within the heat exchanger;

Changing the pressure so that water flows into the process fluid;

Replacing the heat exchanger or heat exchanger bundle; or

Isolating, bypassing, or otherwise removing the leaking heat exchanger from service until it is otherwise repaired.

If the repair is technically infeasible without a shutdown and the total strippable hydrocarbon concentration or total hydrocarbon mass emissions rate is initially and remains less than the delay of repair action level for all monitoring periods during the delay of repair, then you may delay repair until the next scheduled shutdown of the heat exchange system. If, during subsequent monitoring, the delay of repair action level is exceeded, then you must repair the leak within 30 days of the monitoring event in which the leak was equal to or exceeded the delay of repair action level.

If the necessary equipment, parts, or personnel are not available and the total strippable hydrocarbon concentration or total hydrocarbon mass emissions rate is initially and remains less than the delay of repair action level for all monitoring periods during the delay of repair, then you may delay the repair for a maximum of 120 calendar days. You must demonstrate that the necessary equipment, parts, or personnel were not available. If, during subsequent monitoring, the delay of repair action level is exceeded, then you must repair the leak within 30 days of the monitoring event in which the leak was equal to or exceeded the delay of repair action level.

The delay of repair action level is a total strippable hydrocarbon concentration (as methane) in the stripping gas of 62 ppmv or, for heat exchange systems with a recirculation rate of 10,000 gallons per minute or less, the delay of repair action level is a total hydrocarbon mass emissions rate (as methane) of 1.8 kg/hr. The delay of repair action level is assessed as described in paragraph (d)(4)(iii)(A) or (B) of this section, as applicable.

Physical modifications to the leaking heat exchanger, such as welding the leak or replacing a tube;

Blocking the leaking tube within the heat exchanger;

Changing the pressure so that water flows into the process fluid;

Replacing the heat exchanger or heat exchanger bundle; or

Isolating, bypassing, or otherwise removing the leaking heat exchanger from service until it is otherwise repaired.