Fugitive emissions from the oil and gas industry continue to be the target of local, state, and federal rule making policies. Emissions, primarily in the form of methane, pose a credibility risk to the industry as adversaries use this topic to vilify the industry and its role in creating a better energy future.
One action the Environmental Protection Agency (EPA) has stepped up in recent years to ensure compliance with the Clean Air Act (CAA) are 114 inquiries. EPA 114 inquiries are the environmental equivalent of an IRS audit that allow the EPA broad oversight over information it deems relevant for determining compliance with the CAA (among other possible uses). The information from a 114 request can then be used in an enforcement action, disclosure to non-governmental organizations (NGOs), plaintiff’s attorneys, state and local agencies, and industry competitors.
As part of an EPA 114 request, producers often find themselves having to conduct large-scale sampling and analysis projects to evaluate their site-specific emissions factors for a given geography. These projects require precision documentation and logistics to be completed in a timely manner and in accordance with the EPA’s requirement. Luckily, SPL has worked on countless 114 inquiries for producers across the United States and has developed SOP’s to seamlessly execute sampling and analysis projects related to EPA 114 inquiries.
A critical component of the sampling and analysis work is ensuring the analytical integrity of the compositional anlaysis of the pressurized hydrocarbon liquids. While a bubble point determination was once thought to be the primary indicator of analytical integrity, this quality check is now just a component of a suite of quality checks laboratories and producers should use to evaluate analytical integrity of the sample. Those quality checks include:
- SAMPLE COLLECTION POINT – IDEALLY, A PRESSURIZED HYDROCARBON LIQUID IS COLLECTED FROM A SAMPLE PORT BETWEEN THE VESSEL AND DUMP VALUE. A SIGHT GLASS SHOULD ONLY BE USED WHEN NO OTHER ADEQUATE SAMPLE PORT IS AVAILABLE.
- SAMPLE COLLECTION TIME – PRESSURIZED HYDROCARBON LIQUID SAMPLES SHOULD BE COLLECTED SLOWLY TO ENSURE THE SAMPLE IS NOT ACCIDENTALLY FLASHED DURING THE PROCESS. SAMPLE COLLECTION RATES SHOULD BE DOCUMENTED, AND NO GREATER THAN 60ML/MIN.
- SAMPLE COLLECTION CONTAINER – CONSTANT PRESSURE, OR “FLOATING PISTON,” CYLINDERS SHOULD BE USED FOR SAMPLES BEING COLLECTED FOR EMISSIONS ESTIMATION PURPOSES. IF USING A CONSTANT VOLUME OR “WATER DRAW” CYLINDER, THERE IS POTENTIAL FOR METHANE AND CO2 TO DISSOLVE ACROSS THE OIL-WATER INTERFACE THUS BIASING THE GAS TO OIL VALUE.
- VESSEL CYCLING – SAMPLES SHOULD BE COLLECTED SOON AFTER THE VESSEL DUMPS TO ENSURE FRESH PRODUCT IN THE PIPING AT THE TIME OF COLLECTION.
- TEMPERATURE AND PRESSURE MEASUREMENT – DEPENDING ON WHERE THE MEASUREMENT IS TAKEN, PRESSURE AND TEMPERATURE FROM THE FIELD CAN BE A SOURCE OF ERROR TO THE SAMPLE, PARTICULARLY WHEN USED IN BUBBLE POINT ANALYSIS. IDEALLY, MEASUREMENTS ARE TAKEN FROM THE VESSEL ITSELF OR CALIBRATED EQUIPMENT AT THE SAMPLE PORT.
To learn more about SPL’s services for EPA 114 audits contact email@example.com