Assessment of Air Emissions at the U S Liquids Exploration and Production Land Treatment Facility

[摘要] This project was initiated to make the first set of measurements documenting the potential for emissions of pollutants from exploration and production (E&P) waste disposal facilities at Bourg, Louisiana and Bateman Island, Louisiana. The objective of the project was to quantify the emissions and to determine whether the measured emissions were potentially harmful to human health of workers and the adjacent community. The study, funded by the Department of Energy (DOE) is designed to complement additional studies funded by Louisiana Department of Natural Resources (LADNR) and the American Petroleum Institute. The distinguishing feature of this study is that actual, independent field measurements of emissions were used to assess the potential problems of this disposal technology. Initial measurements were made at the Bourg, LA facility, adjacent to the community of Grand Bois in late 1998-early 1999. Emission measurements were performed using aluminum chambers placed over the surface of the landfarm cells. Air was pulled through the chambers and the concentration of the contaminants in the air exiting the chambers was measured. The contaminants of interest were the ''BTEX'' compounds (benzene, toluene, ethylbenzene and xylene), commonly found in E&P wastes and hydrogen sulfide, a noxious gas present naturally in many E&P wastes and crude oils. Measurements indicated that emissions were measurable using the techniques developed for the study. However, when the air concentrations of these contaminants that developed above the landfarm cells were compared with standards for workers from the Occupational and Safety and Health Association (''OSHA'') and for communities (Louisiana's ambient air standards), levels were not of concern. Since amounts of wastes being processed by the Bourg facility were considerably lower than normal, a decision was made to continue the study at the Bateman Island facility near Morgan City, LA. This facility was receiving more normal loadings of E&P wastes. Additional emission measurements were made at the Bateman Island facility within cells over a range of ''ages'', from those most recently loaded with E&P wastes to cells that have not received wastes for 9 months or more. As expected the greatest chance for emissions when the cell is most recently loaded. Again, measured fluxes did not produce air concentrations that were of concern. As expected, the highest fluxes were observed in the cells that had recently received wastes and older cells had very low emissions. Measurements of emissions of hydrogen sulfide (H{sub 2}S) were also conducted at these two facilities. Levels of emissions were similar to the xange observed in the literature for natural salt marshes that surround these facilities. Production of sulfide within the cells was also measured by the most sensitive techniques available and measured sulfide production rates were low in the samples tested. The only potential concern at the facility with regards to sulfide was the levels of sulfide emitted from the sumps. The facility logbook at Bourg was analyzed to determine a time sequence of activities over 1998-1999. The Louisiana Department of Environmental Quality conducted a time-series of air concentrations for hazardous air pollutants during this period at the fenceline of the Bourg facility. These data were characterized by periods of static concentrations interspersed with peaks. A series of peaks were analyzed and compared with logbook records for the activities occurring at the time. In reverse fashion, a set of activities documented by the logbook was examined and the concentrations of benzene that developed from these activities were documented. No direct correlation could be made with the observed peaks and any activities suggesting that concentrations of benzene at the fenceline may be the result of a complex suite of activities including onsite activities not documented in the logbook (loading of the cells by truck haulers) and offsite activities (automobile traffic). Based on these results several recommendations were made. These include maintaining loading of wastes at rates observed during the study period and further evaluating sulfide emissions from the sump system. A scientifically based cell management approach that would maintain benzene levels below levels of concern is possible based on the simple emission models calibrated during this study. However, measured emission rates and long-term records of air concentrations near the facilities suggest that this is not necessary at present.

[发布日期] 2000-12-01 [发布机构] State Of Louisiana

[关键词] Aluminium;Management;02 Petroleum;Environmental Quality;Sulfides