January 3, 2014

GEM Petitions EPA and Gains Approval for Alternative Monitoring to Comply with New Source Performance Standards (NSPS) for Refineries

Refineries throughout the United States are subject to numerous air toxics regulatory requirements imposed by EPA, State and local authorities.  Included in these requirements are the New Source Performance Standards outlined in NSPS J and Ja.  Among other things, NSPS J/Ja prohibit the owner or operator of a fuel gas combustion device (FGCD) from burning any gas generated at a petroleum refinery that contains hydrogen sulfide (H2S) in excess of 162 parts per million by volume (ppmv).

All FGCD’s used to combust waste gases within a refinery are subject to requirements of NSPS J/Ja.  Fixed or permanent control equipment such as flares, process heaters and boilers are most commonly used for the destruction of these gases but also included are mobile or portable devices such as thermal oxidizers, vapor combustors, and internal combustion engines.  By falling under the requirements of NSPS J/Ja, refinery personnel or their contractors must perform monitoring to ensure H2S levels stay below required thresholds. 

Historically, EPA has required H2S monitoring be performed using a Continuous Monitoring System or CMS as outlined in (40CFR §§ 60.105(a)(4) and 60.107a(a)(2)).  A CMS monitoring system is a large, complex, and sensitive monitoring instrument which, although highly accurate, presents challenges when utilized on mobile and temporary equipment.  For complete regulatory compliance, all mobile contractors operating fuel gas combustion devices (vapor destruction equipment) would have to have CMS monitoring units installed to comply with NSPS J/Ja.

Installing CMS monitoring equipment on each vapor combustor within the largest fleet of combustors in North America was a daunting task to consider.  Recognizing the EPA’s goal was to minimize the combustion of H2S, GEM was first to petition the EPA and propose an Alternative Monitoring Plan (AMP).  The EPA’s approval allows GEM to meet the H2S monitoring requirements of NSPS J/Ja through the use of handheld monitors or colorimetric testing.  This win-win situation maintains customer regulatory compliance while keeping costs down.

Key features of GEM’s AMP include pretreatment of vapor streams to ensure waste gas H2S levels remain below required thresholds (when necessary), FGCD inlet vapor stream sampling, field testing for H2S using EPA approved instruments and methodology, and recording of testing results which are maintained as permanent records for customer NSPS J/Ja compliance. 

For questions regarding compliance to NSPS J/Ja or to review a full copy of GEM’s EPA-issued Alternative Monitoring Plan (AMP), please send us an email at

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