Section 721.957  Standards:  Valves in Gas/Vapor Service or in Light Liquid Service

a)         Each valve in gas/vapor or light liquid service must be monitored monthly to detect leaks by the methods specified in Section 721.963(b) and must comply with subsections (b) through (e), except as provided in subsections (f), (g), and (h) and Sections 721.961 and 721.962.

b)         If an instrument reading of 10,000 ppm or greater is measured, a leak is detected.

c)         Monitoring Frequency.

1)         Any valve for which a leak is not detected for two successive months may be monitored the first month of every succeeding quarter, beginning with the next quarter, until a leak is detected.

2)         If a leak is detected, the valve must be monitored monthly until a leak is not detected for two successive months,

d)         Leak repair.

1)         When a leak is detected, it must be repaired as soon as practicable, but no later than 15 calendar days after the leak is detected, except as provided in Section 721.959.

2)         A first attempt at repair must be made no later than five calendar days after each leak is detected.

e)         First attempts at repair include, but are not limited to, the following best practices where practicable:

1)         Tightening of bonnet bolts.

2)         Replacement of bonnet bolts.

3)         Tightening of packing gland nuts.

4)         Injection of lubricant into lubricated packing.

f)         Any valve that is designated, as described in Section 721.964(g)(2), for no detectable emissions, as indicated by an instrument reading of less than 500 ppm above background, is exempt from the requirements of subsection (a) if the valve:

1)         Has no external actuating mechanism in contact with the hazardous secondary material stream.

2)         Is operated with emissions less than 500 ppm above background as determined by the method specified in Section 721.963(c).

3)         Is tested for compliance with subsection (f)(2) initially upon designation, annually, and at other times as requested by the Agency.  The Agency must request any compliance testing at times other than annually in writing to the remanufacturer or other person that stores or treats the hazardous secondary material.

g)         Any valve that is designated, as described in Section 721.964(h)(1), as an unsafe-to-monitor valve is exempt from the requirements of subsection (a) if both of the following conditions are fulfilled:

1)         The remanufacturer or other person that stores or treats the hazardous secondary material determines that the valve is unsafe to monitor because monitoring personnel would be exposed to an immediate danger as a consequence of complying with subsection (a); and

2)         The remanufacturer or other person that stores or treats the hazardous secondary material adheres to a written plan that requires monitoring of the valve as frequently as practicable during safe-to-monitor times.

h)         Any valve that is designated, as described in Section 721.964(h)(2), as a difficult-to-monitor valve is exempt from the requirements of subsection (a) if all of the following conditions are fulfilled:

1)         The remanufacturer or other person that stores or treats the hazardous secondary material determines that the valve cannot be monitored without elevating the monitoring personnel more than two meters above a support surface;

2)         The hazardous secondary material management unit within which the valve is located was in operation before January 13, 2015; and

3)         The owner or operator of the valve follows a written plan that requires monitoring of the valve at least once per calendar year.

(Source:  Added at 40 Ill. Reg. 11367, effective August 9, 2016)