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42 U.S.C. 7401 et seq.
57 FR 61992, Dec. 29, 1992, unless otherwise noted.
61 FR 34158, July 1, 1996, unless otherwise noted.
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| Tank design capacity (cubic meters) | Maximum HAP vapor pressure of off-site material managed in tank (kilopascals) |
Tank control level |
|---|---|---|
| Design capacity less than 75 m3 | Maximum HAP vapor pressure less than 76.6 kPa | Level 1. |
| Design capacity less than 75 m3 | Maximum HAP vapor pressure equal to or greater than 76.6 kPa | Level 2, except that fixed roof tanks equipped with an internal floating roof and tanks equipped with an external floating roof as provided for in § 63.685(d)(1) and (2) shall not be used. |
| Design capacity equal to or greater than 75 m3 and less than 151 m3 | Maximum HAP vapor pressure less than 13.1 kPa | Level 1. |
| Maximum HAP vapor pressure equal to or greater than 13.1 kPa | Level 2. | |
| Design capacity equal to or greater than 151 m3 | Maximum HAP vapor pressure less than 5.2 kPa | Level 1. |
| Maximum HAP vapor pressure equal to or greater than 5.2 kPa | Level 2. |
[80 FR 14283, Mar. 18, 2015]