The Environmental Protection Bureau of Changhua County has proposed “2013 long term background monitoring project for ozone precursor for Changhua County” in order to set up the background data for ozone precursors and to enhance the ozone control effectiveness. In the project, OP-FTIR is used to perform background survey work for volatile organic compound. Moreover, through actions such as ozone control mechanism analysis, ozone control project revision, and the evaluation of the feasibility of ozone action days, the work performance of ozone control of Changhua County is then enhanced. Finally, the work results are briefed as in the followings:
I Monitoring results and air quality analysis
(1) Tungkang Township of Dacheng Hsiang
Most of the concentrations of VOCs species in the Dacheng District are lower than the surrounding standard. Moreover, most of VOCs species are not detectable. In the time periods when south-bound wind dominates in Dacheng District, the frequency of appearance of high concentrations of species such as methane, ammonia, ozone, methanol, CO, difluoro-monochloro-methane and acetylene is in the increasing trend. Through the mass point diffusion simulation result sponsored by National Science Council, it can be seen that sea-land wind mechanism has dominated the pollutant diffusion mechanism in the Dacheng District.
(2) Central Taiwan Science Park Erhlin District
Affected by the construction of the infrastructure engineering of Central Taiwan National Science Park Erhlin District Base and the road broadening engineering of the Erh-hsi road, the average PM10 concentrations from 2010 to 2013 are obviously higher, although the concentrations are in descending trend year by year, yet it is still higher than that of year 2009. Affected by the entire air quality trend change in the air quality area of central Taiwan, the annual average concentrations of three counties and cities in central Taiwan are significantly higher starting from 2010, however, only theErhlin test station shows a descending trend.
For the monitoring of VOCs species, since the peripheral industries in Central Taiwan Science Park Erhlin Base are mostly agriculture and pasturage, environmental background species like methane, ammonia and nitrogen are significant. Since the test lines are affected by the neighboring factories, temples and the burning actions in the farm field, species such as toluene, butanone, ethyl acetate and multi-rings aromatic hydrocarbons are more significant. And the entire pollutant concentration is lower than the surrounding standard.
(3) Constantly complained or major pollution source
From the monitoring results of PU leather industry, after a comparison is made among wind direction, timing for batch appearance, data of the raw material used, and the operation situation of the factories, the correlation was found to be very high. Moreover, synchronous appearance was seen for the timing of appearance of high concentrations of dimethylformamide, butanone and ethyl acetate, hence, it was judged that the pollution source comes from that industry.
From the monitoring results of the printing and dying industry and from factors such as timing of appearance of the species, wind direction, raw material and the released species emitted from the process,it was estimated that three species such as isopropyl alcohol, ethyl acetate and toluene should be contributed by the same pollution source, hence, it was judged that these three species have very high probability to be generated by dying and printing industry.
II Ozone control strategy
According to the historical air quality analysis results and ozone control mechanism, it was seen that future ozone control job in Changhua County should be emphasized on VOCs control. Suggestions for future control jobs are: Reduction of the pollution quantity, control on the release quantity, and the fulfillment of environmental education. They include: Make strict requirement on VOCs release control, perform entire checking of the release quantity of industrial VOCs, make census of dead vehicles in different areas and different sections, and enhance people’s ozone control recognition in the daily life.
After initial evaluation of ozone action days, it was suggested that it can be announced by SIP project of Changhua County, and the announcement condition should be based on 8 hours average ozone concentration of 75~95 ppb of the next day in the air quality area of central Taiwan. The announcement targets include: Bureau, department or office in the County Government, school or enterprises, etc. And the announcement method can be email or text message of mobile phone. Since ozone action days is basically an activity for the quantity reduction among all the nationals of this country, it should be based on the view point of “reduction of the hazard to the health” to ask the general public to reduce the release of VOCs in the daily life, after the ozone control consciousness of the general public is enhanced, the promotional job in the second stage can then be launched. Eventually, the effectiveness of the quantity reduction among all the people in this country can then be seen.
