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A pilot study was conducted in application of the U.S. Environmental Protection Agency (EPA) Methods 325A/B variant for monitoring volatile organic compounds (VOCs) near two oil and natural gas (ONG) production well pads in the Texas Barnett Shale formation and Colorado Denver-Julesburg Basin (DJB), along with a traffic-dominated site in downtown Denver, CO. As indicated in the EPA method, VOC concentrations were measured for 14-day sampling periods using passive-diffusive tube samplers with Carbopack X sorbent at fenceline perimeter and other locations. VOCs were significantly higher at the DJB well pad versus the Barnett well pad and were likely due to higher production levels at the DJB well pad during the study. Benzene and toluene were significantly higher at the DJB well pad versus downtown Denver. Except for perchloroethylene, VOCs measured at passive sampler locations (PSs) along the perimeter of the Barnett well pad were significantly higher than PSs farther away. At the DJB well pad, most VOC concentrations, except perchloroethylene, were significantly higher prior to operational changes than after these changes were made. Though limited, the results suggest passive samplers are precise (duplicate precision usually ≤10%) and that they can be useful to assess spatial gradients and operational conditions at well pad locations over time-integrated periods.Implications: Recently enacted EPA Methods 325A/B use passive-diffusive tube samplers to measure benzene at multiple fenceline locations at petrochemical refineries. This pilot study presents initial data demonstrating the utility of Methods 325A/B for monitoring at ONG facilities. Measurements revealed elevated concentrations reflective of production levels and spatial gradients of VOCs relative to source proximity at the Barnett well pad, as well as operational changes at the DJB well pad. Though limited, these findings indicate that Methods 325A/B can be useful in application to characterize VOCs at well pad boundaries.PAPER HISTORY

This equation indicates that titanium is somewhat more effective as a deoxidizer in steel than would be calculated from the equation of Chipman, which gives for the reaction AF°= -151,000 + 57.3 The deoxidation constants usually are expressed as the reciprocals of the constants of the deoxidation reactions; i. e., K = [%Ti] X [%FeO]2.The values of these constants calculated from the authors' and from Chipman's equations are compared in Table II at several temperatures.

Rapid Determination of HydroXYl 61 locities of certain ketones with the above reagents have been made. The results suggest that steric hindrance of the carbonyl group is responsible for wide variations in the rate of reaction.3. It has been shown that the addition of pyridine displaces the oxime synthesis equilibrium in the direction of completion. Wilmington, Del.

The term phosphyl is taken to embrace phosphonyl, phosphoryl, phosphinyl, and phosphiiie oxide (R. I;. Hudson and I,.