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Title 40

Displaying title 40, up to date as of 6/11/2026. Title 40 was last amended 6/11/2026.
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Table 1 to Subpart JJJJJ of Part 63—Emission Limits

As stated in § 63.8405, you must meet each emission limit in the following table that applies to you:

For each . . . You must meet the following emission limits . . . Or you must comply with the following . . .
1. Collection of all tunnel kilns at facility, including all process streams HF, HCl, and Cl2 emissions must not exceed 26 kg/hr (57 lb/hr) HCl equivalent, under the health-based standard, as determined using Equations 2 and 3 Not applicable.
2. Existing large tunnel kiln (design capacity ≥10 tons per hour (tph) of fired product), including all process streams a. PM emissions must not exceed 0.018 kg/Mg (0.036 lb/ton) of fired product i. PM emissions must not exceed 6.6 mg/dscm (0.0029 gr/dscf) at 17% O2; or
ii. Non-Hg HAP metals emissions must not exceed 0.0026 kg/hr (0.0057 lb/hr).
b. Hg emissions must not exceed 2.1 E-05 kilogram per megagram (kg/Mg) (4.1 E-05 pound per ton (lb/ton)) of fired product i. Hg emissions must not exceed 7.7 micrograms per dry standard cubic meter (µg/dscm) at 17% O2; or
ii. Hg emissions must not exceed 2.5 E-04 kg/hr (5.5 E-04 lb/hr).
3. Existing small tunnel kiln (design capacity <10 tph of fired product), including all process streams a. PM emissions must not exceed 0.19 kg/Mg (0.37 lb/ton) of fired product i. PM emissions must not exceed 4.8 mg/dscm (0.0021 gr/dscf) at 17% O2; or
ii. Non-Hg HAP metals emissions must not exceed 0.047 kg/hr (0.11 lb/hr).
b. Hg emissions must not exceed 1.7 E-04 kg/Mg (3.3 E-04 lb/ton) of fired product i. Hg emissions must not exceed 91 µg/dscm at 17% O2; or
ii. Hg emissions must not exceed 8.5 E-04 kg/hr (0.0019 lb/hr).
4. New or reconstructed large tunnel kiln (design capacity ≥10 tph of fired product), including all process streams a. PM emissions must not exceed 0.0089 kg/Mg (0.018 lb/ton) of fired product. i. PM emissions must not exceed 3.2 mg/dscm (0.0014 gr/dscf) at 17% O2; or
ii. Non-Hg HAP metals emissions must not exceed 0.0026 kg/hr (0.0057 lb/hr) of fired product.
b. Hg emissions must not exceed 1.4 E-05 kg/Mg (2.8 E-05 lb/ton) of fired product i. Hg emissions must not exceed 6.2 µg/dscm at 17% O2.
ii. Hg emissions must not exceed 1.6 E-04 kg/hr (3.4 E-04 lb/hr).
5. New or reconstructed small tunnel kiln (design capacity <10 tph of fired product), including all process streams a. PM emissions must not exceed 0.015 kg/Mg (0.030 lb/ton) of fired product i. PM emissions must not exceed 4.7 mg/dscm (0.0021 gr/dscf) at 17% O2; or
ii. Non-Hg HAP metals emissions must not exceed 0.047 kg/hr (0.11 lb/hr) of fired product.
b. Hg emissions must not exceed 1.7 E-04 kg/Mg (3.3 E-04 lb/ton) of fired product i. Hg emissions must not exceed 91 µg/dscm at 17% O2.
ii. Hg emissions must not exceed 8.5 E-04 kg/hr (0.0019 lb/hr).