Field study and source attribution for PM_2.5 and PM₁₀ with resulting reduction in concentrations in the neighborhood north of the Houston Ship Channel based on voluntary efforts

Figures & data

Figure 1. Google Earth map of the Clinton Drive monitoring site location and the surrounding area.

Figure 2. Quarterly mean PM_2.5 concentration at Clinton Drive from FRM filter samples.

Figure 3. Quarterly mean PM₁₀ concentration at Clinton Drive from HiVol filter samples.

Figure 4. Mean TEOM (not an FEM) PM_2.5 concentration at Clinton Drive compared with other sites, calendar year 2006.

Figure 5. Mean reconstructed soil component at Clinton Drive, summer 2006, compared with other sites from summer 2005.

Figure 6. Map of monitoring sites for PM_2.5 in 2006 used in intercomparisons.

Figure 7. Teflon filter 2005–2006 average composition—121 days with a predominant wind direction, 15 North African dust days, and 1 fireworks day, December 31, 2006.

Figure 8. Wind directionality for “calcium & sulfate” factor (μg/m³) on 57 days used in early PMF analysis.

Figure 9. Wind directionality for “soil” factor (μg/m³) on 57 days used in early PMF analysis.

Figure 10. Silicon concentrations at Clinton Drive, 2005–2010, all unflagged data, 612 samples.

Figure 11. Histogram for the distribution of silicon values at Clinton Drive, 2005–2010.

Table 1. Mean ratios of crustal elements to silicon from six PM_2.5 speciation sites in three urban areas, North African dust versus other days, and paired t test for differences

North African Dust	AQS-ID	No. of Obervations	Al/Si Mean	Fe/Si Mean	Ti/Si Mean
Dallas Convention Center	481130050	23	0.524	0.500	0.041
Dallas Hinton Street	481130069	23	0.427	0.356	0.032
Houston Aldine	482010024	15	0.500	0.390	0.040
Houston Clinton Drive	482011035	53	0.496	0.470	0.044
Houston Deer Park	482011039	24	0.451	0.302	0.035
Corpus Christi Dona Park	483550034	12	0.530	0.351	0.040
Average across sites			0.488	0.395	0.038
Not North African Dust	AQS-ID	No. of Obervations	Al/Si Mean	Fe/Si Mean	Ti/Si Mean
Dallas Convention Center	481130050	384	0.499	1.379	0.066
Dallas Hinton Street	481130069	322	0.293	0.911	0.026
Houston Aldine	482010024	189	0.601	1.323	0.068
Houston Clinton Drive	482011035	471	0.453	1.001	0.053
Houston Deer Park	482011039	370	0.374	0.722	0.025
Corpus Christi Dona Park	483550034	190	0.740	0.983	0.089
Average across sites			0.493	1.053	0.055
			Al/Si Mean	Fe/Si Mean	Ti/Si Mean
Two-sided, paired t statistic, P value			0.922	0.001	0.145

Table 2. Ten factors derived with PMF version 3.0 using Clinton Drive data

PMF Factors	Constituents	Characteristics
Crustal material	Si, Al, Ti, Fe	Significant downward trend
Sea salt	Na, Cl	Spring, south winds
Ammonium sulfate	SO4, NH4	Fall
Fires	K, OC, EC, Br	Low in summer
Ammonium nitrate	NO3, NH4	Winter
Heavy-duty vehicles	EC, Cr, Mn, Fe, Cu	Higher weekday versus weekend
Light-duty vehicle	OC, EC, Zn	Lower in spring
Calcium sulfate used to patch local parking lots	Ca, SO4	Weekday, summer, significant downward trend
Sodium sulfate, from sea salt chemistry	Na, SO4	Spring
Vanadium and nickel from oil combustion	V, Ni	Winter, east and west winds

Table 3. Ten factors’ contribution to total mass at Clinton Drive, 2005–2012

PMF Factors	Mass (μg/m^3)
Crustal material	0.960
Sea salt	0.454
Ammonium sulfate	5.199
Fires	2.087
Ammonium nitrate	0.639
Heavy-duty vehicles	0.729
Light-duty vehicle	2.679
Vanadium and nickel from oil combustion	0.067
Calcium sulfate used to patch local parking lots	1.832
Sodium sulfate, from sea salt chemistry	0.684
Total	15.33

Figure 12. Calcium sulfate factor (μg/m³) in 2006–2008 and 2009–2012 by 30˚ wind bin.

Figure 13. Soil/crustal factor (μg/m³) in 2006–2008 and 2009–2012 by 30˚ wind bin.

Figure 14. Annual average PM_2.5 DRI reconstructed species concentrations (*see figure) at Clinton Drive.

Figure 15. Annual average PM_2.5 DRI reconstructed species concentrations at Aldine.