The City of Houston’s Mobile Ambient Air Moitoring Lab 休斯敦移动的空气的环境监测实验室的城市

1、james rhubottom, jr., dr. youjun qin, dr. peter chen: dr. wei-yeong wanginitial maaml monitoring locationsa styrene emission back trajectory showing the benefits of the new softwareback trajectory (upgraded software)back trajectories and resultant wind directions from a maaml monitoring run at a loc

2、al storage drum plantnbased upon the combination of collected maaml data, ir camera footage, and ongoing plant investigations performed by field investigators from baqcs complaints and community assistance section (cca), the facility voluntarily agreed to make changes as noted below.nequipment modif

3、ications, namely removal of rain caps from all process stacksnequipment replacement along with height increases for four vent stacks that emit vocs (typically paint solvents) directly to the atmospherenusing paints with lower voc concentrations to reduce voc emissionsncca investigators will incorpor

4、ate the preceding ir camera video capture in a upcoming follow-up investigation at this facility.case study b voc complaintsnduring december 2008, cca personnel fielded approximately 16 citizen complaints centering on an adjacent petrochemical complex known for sourcing unplanned emission events. nm

5、aaml data showed two unknown peaks in addition to peaks from compounds in the maaml compound list. upon completion of a library comparison, the software tentatively identified the peaks as 2,4,4-trimethylpentene (tmp) and 4-vinyl-1-cyclohexene (vch).na review of plant msd sheets and process streams

6、performed by engineers in baqcs special initiatives section (si) and compared with collected maaml data centering upon the two unknown peaks showed a strong correlation to lean oil. case study b voc complaintscase study b voc complaintsnin this investigation, the maaml became a baqc resource to help

7、 in answering citizens air quality complaints.nin this role, the maaml, with its onboard gc/ms instrumentation, independently verified the voc source. in addition, mlp chemists also provided a reasonable estimate of the potential hazards associated with the emissions event.nall relevant baqc section

8、s made important contributions in resolving the citizens complaintscase study b voc complaintscase study c affecting changentimeline for styrene emissions reduction:case study c affecting changeback trajectory for a 13.9ppbv styrene emissions hourly average helped showcase the need for the inclusion

9、 of styrene as a compound of interest for tceq monitoring.back trajectory for a 12.9ppbv styrene emissions hourly average added to the rationale for styrene inclusion.case study c affecting changebaqc & mlp - additional successesnthe city negotiated an agreement with a local environmental waste

10、processing firm with an established history of nuisance violation emissions.na metal recycling facility agreed to several modification to their plant along with the incorporation of changes to their operational proceduresna prominent dairy processing plant agreed to switch from diesel motors to elec

11、tric motors for their refrigeration trucks to address citizen complaints about particulates from the diesel motor exhaustsnfacilities have markedly reduced or ceased operations upon seeing the maaml deployed near their facilitythe future of local-scale monitoring baqc nan recent agreement between th

12、e city of houston and the county attorneys office for harris county allows for expansion of maaml local-scale ambient air monitoringthe future of local-scale monitoring baqc nthe mlp has begun seeking funding to expand maaml analytical capability to analyze for polar vocs, a set of compounds not cur

13、rently available for analysis via the maaml.nthis enhancement will allow mlp chemists to add to the maaml compound list carbonyls such as methyl ethyl ketone (mek), a chemical widely used as a solvent for paint applications, especially at a major drum manufacturing facility targeted by the bureau as

14、 a result of numerous citizen complaintsnadditionally, the funding allows the mlp to expand its scope to monitor more facilities that encompass more industriesnthe maaml continues to both demonstrate its current value to the bureau while continuing to find opportunities to add greater value in local-scale air monitoring. nthe maaml stands as one of several viable options available to bureau personnel to support nuisance violation investigations, especially those investigations stemming from citizen complaints.acknowledgementsu.s. epa, region 6u.s. epatexas commission on environmental qualit