Document 3ez4o5ND0No010BDKXyQDgGYJ

To: FGJ, JliC, DRB From: J. C. Ledvina Date: July 24, 1990 Subject: VCM NESHAPs Revisions Attached is a copy of the recently promulgated revisions to the VCM NESHAPs. These revisions are the result of a lawsuit over certain provisions of the 9/30/86 changes to the standard. Vista was a party to this suit. The revisions are generally favorable for us although the benefit is relatively minor. The definition of "exhaust gas" has been clarified to exclude leaks from being considered an "exhaust gas". Vent headers receiving "exhaust gases" are considered subject to the standard even if they contain less than 10'/. VCM. Relief valve discharges routed to a control device will not be considered exceedances of 61.65(a) if the control device reduces emissions as specified in the standard. Flares are allowed as control devices. Previously, some companies were subjected to enforcement action for RVDs routed to control devices. The standard for leaks from pumps has been revised so that a drip from a double mechanical seal is not a "leak" subject to the standard. Mechanical seal drips detected during the weekly pump inspection do not need to be repaired if there is no detectable (above background) VOC emissions coming from the dripping seal . VDC determination is done with a portable analyzer. Leaks from double mechanical seals found at times other than during the weekly inspection do not need to be immediately repaired if the frequency cf leaks is consistent with design considerations or past operating experience. This language was added to address concerns that even new seals leak a little. To qualify for this, each plant must have a written criterion against which they exclude repairs. Since this is new, you need to write a criterion. If the leak is still occurring at the time of the weekly inspection, the drip needs to be checked with a portable analyzer to see if VOCs are present. If they are, the leak must be repaired. The definition of "EDC purification1' has been changed to exclude in termedia te storage tanks. Crude EDC tanks no longer need to be routed to a control device. This isn' t much help for us since Louisiana hasn t changed LESHAP and we already spent the money to control these tanks. The definition of "3-hour period" was changed to avoid a situation where a one hour exceedance of a control device standard can cause three violations. Since Oklahoma and Mississippi incorporate national standardsVJA'.0001165130 A reference, these changes are effective immediately in those states, Louisiana needs to modify LESHAPs before the changes are effective for LCVCM. Give me a call if you have questions or would like to discuss. y /jjDG Led v in cc : q/\ RAC, HDG, RMS, WLM, DLC, THH VAB.0001165131