Meteorological Monitoring Requirements of the Petroleum Refinery Rule

The Petroleum Refinery Rule Package was published in the Federal Register on December 1, 2015 officially starting the two (2) year process of preparing for and implementing the 40 CFR Part 63 Subpart CC benzene fenceline monitoring (BFM) requirements so that your refinery is in compliance on February 1, 2018.  One (1) specific BFM requirement included as part of the 40 CFR Part 63, Subpart CC is the collection of hourly meteorological data.  Many refineries may be located near a major airport that operates a U.S Weather Service (USWS) station and/or currently has an onsite meteorological monitoring system.  However, there are a few nuances to the final rule that need to be understood to determine if either of these sources of meteorological data meet the requirements of the rule.

Specifically, 40 CFR Part 63.658(d) requires refineries to collect and record hourly average temperature, barometric pressure, wind speed, and wind direction meteorological data.  Refineries that utilize a near-field source correction or an alternative test method that provides time-resolved measurements are required to use an on-site meteorological system in accordance with Section 8.3 of Method 325A.  Refineries not utilizing near-field correction or alternative test methods may utilize USWS meteorological stations within 40 kilometers.

Refineries that currently have an on-site meteorological monitoring station and are planning on utilizing the data to meet the BFM requirements may need to take a closer look at their existing meteorological monitoring systems.  40 CFR Part 63.14 incorporates U.S. EPA’s “Quality Assurance Handbook for Air Pollution Measurement Systems, Volume IV: Meteorological Measurements Version 2.0” (QA Handbook) by reference.  The QA Handbook summarizes calibration and standardization procedures and requires meteorological monitoring systems to be audited semi-annually.  Unfortunately many pre-packaged meteorological monitoring systems were not designed with the calibration procedures outlined in the QA Handbook in mind and are not able to be calibrated.  In addition the QA Handbook outlines criteria for siting a meteorological monitoring systems and minimum sensor resolution and accuracy criteria that will have to be met to utilize the meteorological data for the BFM requirements.

For refineries that are able to utilize USWS data, it is in your best interest to evaluate the USWS station to determine if it is representative of the conditions at your refinery.  The evaluation would be very similar to the representativeness analysis required as part of air quality modeling demonstrations for Prevention of Significant Deterioration permitting.  Some things to consider include:

• Distance,
• Differences in base elevations,
• Significant topographic features between your refinery and the USWS station,
• Proximity to large bodies of water, and
• Differences is land use patterns.

These are all items that will influence meteorological data between your refinery and the meteorological data you may want to utilize at a USWS station.  When considering whether to utilize USWS station or an on onsite meteorological monitoring system for meteorological data there are some additional items to consider.

• Operational control of an onsite meteorological monitoring system vs. relying on USWS station,
• Differences in Quality Assurance (QA) objectives between onsite meteorological monitoring and USWS station, and
• Availability shorter averaging periods from USWS [currently 1-minute and 5-minute average wind speed and direction is available monthly from the National Climatic Data Center (NCDC)].

For assistance evaluating your existing on-site meteorological monitoring system and/or evaluating USWS station to meet the fenceline benzene monitoring requirements please contact Dan Dix at ddix@all4inc.com or 610.933.5246 x118.