EPA-600/4-77-013 February 1977 Environmental Monitoring Series CARBON MONOXIDE LEVELS IN CHARLOTTE, NORTH CAROLINA Environmental Monitoring and Support Laboratory Office of Research and Development U.S. Environmental Protection Agency Las Vegas, Nevada 89114 ------- RESEARCH REPORTING SERIES Research reports of the Office of Research and Development, U.S. Environmental Protection Agency, have been grouped into five series. These five broad categories were established to facilitate further development and application of environmental technology. Elimination of traditional grouping was consciously planned to foster technology transfer and a maximum interface in related fields. The five series are: 1. Environmental Health Effects Research 2. Environmental Protection Technology 3. Ecological Research 4. Environmental Monitoring 5. Socioeconomic Environmental Studies This report has been assigned to the ENVIRONMENTAL MONITORING series. This series describes research conducted to develop new or improved methods and instrumentation for the identification and quantification of environmental pollutants at the lowest conceivably significant concentrations. It also includes studies to determine the ambient concentrations of pollutants in the environment and/or the variance of pollutants as a function of time or meteorological factors. This document is available to the public through the National Technical Informa- tion Service, Springfield, Virginia 22161. ------- EPA-600/4-77-013 February 1977 CARBON MONOXIDE LEVELS IN CHARLOTTE, NORTH CAROLINA by Norman E. Hester Monitoring Operations Division Environmental Monitoring and Support Laboratory Las Vegas, Nevada 89114 and John Prince Lockheed Electronics Company, Inc. 4220 S. Maryland Parkway Las Vegas, Nevada 89109 U.S. ENVIRONMENTAL PROTECTION AGENCY OFFICE OF RESEARCH AND DEVELOPMENT ENVIRONMENTAL MONITORING AND SUPPORT LABORATORY LAS VEGAS, NEVADA 89114 ------- DISCLAIMER This report has been reviewed by the Environmental Monitoring and Support Laboratory-Las Vegas, U.S. Environmental Protection Agency, and approved for publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. ii ------- INTRODUCTION AND SUMMARY A review of the air quality data for Charlotte, North Carolina, taken over the last 3 years (1973-1976)-has shown excessively high ambient carbon monoxide readings. Carbon monoxide levels exceeding the Federal 8-hour average standard were a regular occurrence. The Region IV office of the U.S. Environmental Pro- tection Agency requested assistance from the Monitoring Operations Division of the Environmental Monitoring and Support Laboratory in Las Vegas, Nevada, to determine if the elevated carbon monoxide concentrations are indicative of an area-wide problem or of a localized "hot spot," and to determine if a more com- prehensive study designed to collect enough data for modeling the area is necessary. Arrangements were made by the Environmental Health Division of the Mecklen- burg County Health Department for four sampling locations. The positions of the four temporary sampling locations and the position of the County station are shown in Figure 1. Personnel and equipment were deployed from Las Vegas during the second and third weeks of April 1976, and data collection began on April 21. Problems were encountered with controlling the temperature at some of the sampling locations and this in turn caused problems with the air monitors. It was necessary to replace two carbon monoxide monitors with instruments that were less temperature sensitive. Overall, at least 16 days of data were taken at each site that could be compared with data at the County site. Wind speed and direction data were obtained from the U.S. Weather Service station near Douglas Municipal Airport. Data collection ceased on May 20. Hourly averages and maximum 8-hour averages have been prepared, and are analyzed in the body of this report. ------- CONCLUSIONS AND RECOMMENDATIONS The maximum 8-hour averages of carbon monoxide data collected at the County station were found to be higher than those collected at the four tempo- rary sites by factors of 1.4, 1.6, 2.7, and 3.3. Based on these data, it is concluded that the carbon monoxide readings reported by the Mecklenburg County Station are not representative of the metropolitan area of the city of Charlotte. Monthly maximum carbon monoxide concentrations seem to have followed a decreasing trend since mid-1973; however, further monitoring is necessary to confirm if such a trend exists or if the decreases were caused by some short term changes in meteorology. Since the data reveal that the Mecklenburg County station is situated at a "hot spot," a more comprehensive study designed to collect data over the greater metropolitan area and to model the carbon monoxide distribution seems unnecessary. Rather, efforts should be directed toward characterizing and controlling the "hot spot." The data taken by the County station should not be considered represen- tative for the city of Charlotte. A better picture of carbon monoxide con- centrations in the metropolitan area can be obtained by dividing the County readings by a factor between 1.4 and 3.4; a rough approximation would be to divide by 2. This type of approximation should only be applied to old data and where no other monitoring data exist. The only valid method to obtain carbon monoxide data that are truly representative of the city is for the County to add additional monitoring sites. ------- EXPERIMENTAL PROCEDURES Equipment Four Beckman/Andros 7000 Dual-Isotope Fluorescence carbon monoxide (CO) monitors were deployed for the study. Hewlett-Packard/Moseley 680 recorders were used to collect the data. Problems with zero drift appeared during the first week of set up with two of the Beckman/Andros carbon monoxide monitors, and these two instruments were replaced with Bendix 8501 infrared carbon monoxide analyzers. Calibration and Standards Each monitor was zeroed and spanned every week day during the study. Zero readings were obtained from catalytic scrubbers until May 13, 1976, when a zero air cylinder was obtained from EPA-Athens, Georgia. The zero air cylinder was compared to the zero air obtained from each of the scrub- ber systems. The commercial zero air cylinder was found to have a concen- tration of 0.7 parts per million (ppm) of carbon monoxide contaminant. The proper corrections were made to the data collected by the temporary monitoring stations. Zero drift was assumed to be linear between calibra- tions and the appropriate correction was applied to each hourly average. The span of each instrument was checked at the same time that the zero was adjusted. Span drift was generally less than 2 percent of full scale. The span value used for calculating concentrations was the average of the readings taken before and after each day's sampling period. A cross-calibration quality control check was performed on each of the four temporary monitors on April 29-30, 1976 by EPA-Athens, Georgia. The commercial standard used by the Athens lab was rated at 9.5 parts per million, the cross check on each of the four temporary monitors using the span factors calculated from the commercial standard used by Las Vegas produced values of 9.5, 9.6, 9.5, and 9.4. The agreement was remarkably good; however, the commercial standard used by Las Vegas was subsequently compared to a National Bureau of Standards Standard Reference Material and found to be 2.5 percent high. The data for the four temporary stations are corrected to the NBS values. The values reported by the County are referenced to the Region IV standard. The net effect would be to introduce an impre- cision between the two sets of data of 2.5 percent. The errors introduced by inaccurate standards coupled to errors introduced in making zero baseline corrections result in an estimated precision between the EPA data and the county data of ± 5 percent. ------- Sampling Locations and Procedures The carbon monoxide monitors were set up at sites arranged by the Mecklenburg County Health Department. Three county fire stations and a local court house were used as sampling sites. The instruments were set up on the second floor of each building and teflon sampling lines were run to the outside of the buildings. The intake port of the sampling lines were situated 3 meters above the ground and 1.5 meters away from the wall of the building. The locations of all sampling stations, both the temporary stations and the permanent county stations, are shown in Figure 1. Meteorological Data Hourly surface weather conditions were furnished by the National Weather Service. The data were taken at Douglas Municipal Airport in Charlotte, North Carolina, which is 8.8 kilometers 261° from true north from the County monitoring station. The wind speed is recorded in the appendices in knots, as given by the National Weather Service (1 knot = 1.85 kilometers per hour). The reported data were taken at five minutes before the hour and are not hourly averages. Figure 1. Location of Sampling Stations in the Central Charlotte Area. ------- RESULTS The hourly averages of carbon monoxide concentration for the four temporary monitoring stations and the County station are summarized in the Appendix. Hourly wind speed and direction readings are also given. The maximum 8-hour average concentrations and the time period covered during the 8 hours were calculated and are summarized in the Appendix. A comparison of the maximum 8-hour average times is quite interesting. Typically, the four temporary sites had their maximum weekday 8-hour averages in time periods centered around either the morning or evening rush hour traffic. The highest readings at the County station, however, often occurred after the morning rush period and before the evening rush. The County station showed rapid increases in carbon monoxide concentration due to heavy morning and evening rushes, but the traffic patterns throughout the midday seem to be extremely high. The County station has its probe located approximately 3 meters above the sidewalk next to a busy downtown street. The street is bordered by banks, stores, and other office buildings which one might expect to draw a lot of midday business. Additionally, tall buildings around the sampling site would tend to prevent ventilation of the pollutants. The net effect would seem to result in the midday values. The direction of the wind seems to have an effect on the concentration of carbon monoxide at the County station. The highest 8-hour averages at the County station (April 23, 30, May 10, and 17) occurred when the wind was blowing from the southwest. The monitor is situated next to a street that runs southwest-northeast. In other words, the highest values occur when the wind is blowing along the street. The maximum 8-hour averages from the four temporary sites and the County site are summarized in Table 1 by date. By examining days when each of the temporary stations had data in common with the County station, it is possible to quantify the amount of bias in the data due to the site location. Fire Station 1 had 22 days of data in common with the County station. Fire Station 2 and the court house each had 17 days of data in common with the County station, and Fire Station 4 had 16 days in common with the County station. Averages of the maximum 8-hour averages were prepared for each station and foe the County station for the days when the stations had data in common. These averages and the ratios are presented in Table 2. The maximum 8-hour average carbon monoxide concentrations at the County station are 1.4 times as high as those at the temporary site in Fire Station 1. The County station data ajre 3.4 times as high as the data at Fire Station 2, 2.7 times as high as data from Fire Station 4 and 1.6 times as high as the data from the court house site. From these ratios, it must be concluded that the carbon monoxide readings reported for the past few years are not representative of the city ------- CO o o o o oc o C3 24 22 20 18 16 14 12 10 8 6 4 2 LEAST SQUARES FIT FEDERAL STANDARD^ 10 mg/m3 OF DATA I JJASONDJFMAMJJASONDJFMAMJJASONDJFMAMJ 1973 1974 1975 1976 MONTH Figure 2. Maximum 8-huur Carbon Monoxide Conrenfrn (: i nns hv MonLti ------- TABLE 1. MAXIMUM 8-HOUR AVERAGES (mg/m3) Dates Fire Station Fire (1976) April: 22 23 24 25 26 27 28 29 30 May: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1 - 5.5 3.2 0.9 2.7 4.0 3.6 4.7 2.6 2.3 2.4 3.0 3.7 1.4 - - 3.6 2.9 3.8 3.3 6.8 - 4.0 3.0 1.3 3.0 3.0 2.8 3.7 Station 2 - - - - - 1.2 1.2 2.2 1.1 1.7 1.6 1.1 1.5 0.5 - 1.1 3.7 1.9 1.3 - - - 0.6 1.3 0.8 1.2 1.0 1.6 2.2 TABLE 2. AVERAGE OF MAXIMUM 8-HOUR Temporary Location Fire Station Fire Station Fire Station Station Concentration 1 3.3 2 1.4 4 1.8 •j i Fire Station Court 4 - - - - - - - - - 1.0 0.9 1.1 0.9 1.3 1.7 1.7 2.1 1.5 2.4 2.1 - 3.3 2.4 1.6 1.3 2.4 2.4 2.0 2.3 AVERAGES FOR County Station Concentration 4 4 4 c 7 4' •7 3. 8 4" •8 1. 9 4" •9 1. 5. - - - - - 3.6 2.5 - 3.8 3.0 1.3 4.1 4.4 - 3.1 4.1 3.2 1.7 4.6 3.4 - 3.0 2.7 2.2 0.8 4.4 3.9 - — COMMON DAYS Ratios 7 1 4 3 1>4 8 3 4 4 - 3.4 9 - ? 7 8 2-7 o County Station 3.7 9.2 3.4 2.6 1.8 3.0 4.4 5.6 8.5 3.5 2.8 - 3.1 6.3 5.7 6.6 3.6 3.1 8.3 7.1 5.2 6.2 5.9 3.8 1.9 7.5 - 2.5 — (mg/m3) Common Days 23 17 16 1 -7 ------- of Charlotte, and better values for representative data can be obtained by dividing the data from the County station by a factor between 1.4 and 3.4; a conservative factor would be to divide by 2. This practice provides only approximations, and a true picture of the Charlotte area can only be obtained by the addition of more monitoring stations by the County. It is interesting to note that during the period covered by this study, no violations of the Federal 8-hour standard were observed at the four temporary sites or the County site. These data seem to fit into a pattern. The data for the maximum 8-hour carbon monoxide readings at the County site for the months when the study took place (April and May) are plotted in Figure 2 along with the maximum 8-hour readings for previous months since July 1973. A decreasing trend seems obvious, and a least squares fit of the data indicates that carbon monoxide 8-hour maximum levels at the County station have decreased, on the average, about 30 percent over the past 3 years. It would seem that even though the County station is situated at a "hot spot," the quality of the air at this location is improving. Such decreases in maximum 8-hour averages could be caused by temporary changes in meteorological conditions over the past 2 years, and may be only temporary. Monitoring at this location should be continued for a number of years to confirm or dis- prove the existence of such a trend. County air pollution officials were unaware of any reasons for such a decreasing trend. However, the Region may wish to investigate possible changes in traffic or industrial emissions and changes in meteorological conditions during this period that could have caused such an apparent trend to develop. It should be noted that even though a decrease in carbon monoxide con- centrations appears to have occurred, the Federal 8-hour standard is still being violated regularly at the County site and control actions are indicated. ------- APPENDIX HOURLY CARBON MONOXIDE AND WIND DATA Notes: (1) F.S. 1 = Mecklenburg County Fire Station 1 F.S. 2 = Mecklenburg County Fire Station 2 F.S. 4 = Mecklenburg County Fire Station 4 (2) Wind speed is given in knots and direction in degrees from true north. (3) cal = Data missing because of instrument calibration. ------- WEDNESDAY, 21 APRIL 76 CONCENTRATIONS (mg/m3) TIME (EOT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 1.8 1.6 1.4 1.0 0.6 0.5 0 F.S. 1 1.8 1.6 1.4 1.0 0.6 0.5 0 F.S. F.S. COURT COUNTY 2 4 HOUSE STATION 1.0 1.0 0.6 0,6 1.0 1.0 2.9 6.5 7.5 7.8 7.8 7.2 7.2 8.4 7.2 5.2 cal 5.5 2.9 2.0 2.0 1.6 1.3 0.6 WIND SPEED 6 6 5 5 3 4 4 8 9 9 11 8 10 12 12 10 11 12 8 8 8 10 15 8 WIND DIRECTION 180 180 180 180 160 140 170 220 220 220 210 200 180 210 200 180 200 170 180 180 170 230 200 180 Maximum 8-hour average Time period for 8-hour maximum Mean winds Time period 7.45 0700- 1500 9.9 208° 0700-1500 10 ------- THURSDAY, 22 APRIL 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 1.8 2.5 2.1 2.3 1.9 3.4 1.6 4.4 8.4 8.2 5.8 3.0 F.S. F.S. COURT COUNTY 2 4 HOUSE STATION 0.3 0.6 1.0 0.6 1.0 1.3 2.6 6.2 cal cal 2.6 2.6 4.9 3.9 2.0 2.3 2.6 2.6 1.3 5.2 5.5 6.8 2.6 2.6 WIND SPEED 10 8 5 5 7 7 6 8 7 7 8 3 8 5 7 4 8 6 3 3 3 5 3 calm WIND DIRECTION 220 190 180 180 160 220 220 260 330 020 340 140 300 330 330 020 280 260 260 230 240 270 280 calm Maximum 8-hour average Time period for 8-H max. Mean winds Time period 3.7 1600- 2400 4.4 260° 1600-2400 11 ------- FRIDAY, 23 APRIL 76 CONCENTRATIONS (mg/ra3) TIME (EOT) Maximum 8-hour average Time period for 8-H max. Mean winds Time period F.S. 1 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 1.0 2.4 2.1 1.4 1.3 0.9 2.3 6.7 11.0 7.0 5.6 2.9 3.6 3.4 2.9 2.5 cal 2.2 1.4 2.6 3.8 5.2 8.3 8.9 5.5 1900- 0300 F.S. 2 F.S. 4 COURT HOUSE COUNTY STATION 9.2 1100- 1900 WIND SPEED 4.6 1100- 0300 WIND DIRECTION 2.0 1.3 1.3 1.0 0.6 1.0 1.3 3.3 3.3 2.6 3.9 6.5 9.1 7.8 11.0 9.1 13.6 11.4 5.2 3.3 3.3 2.9 4.2 3.9 6 6 8 5 5 3 5 4 7 8 9 4 5 6 3 7 8 10 6 5 3 5 calm(O) calm(O) 350 360 350 350 350 320 010 010 010 360 010 230 230 260 160 240 230 210 190 190 140 220 calm calm 192° 12 ------- SATURDAY, 24 APRIL 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0550 0550-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 7.8 5.4 2.3 1.5 1.8 2.9 2.1 1.5 1.4 1.5 1.2 1.1 1.1 1.1 1.3 1.1 1.3 1.3 1.9 2.1 2.3 1.4 0.8 F.S. F.S. 'COURT COUNTY 2 4 HOUSE STATION 3.9 2.6 1.6 1.6 1.0 1.0 2.0 2.6 2.9 3.3 3.3 3.3 2.9 3.3 2.6 2.9 3.0 3.9 3.6 3.6 3.9 3.3 2.0 1.6 WIND WIND SPEEB DIRECTION 4 6 3 calm(O) calm(O) calm(O) 3 4 9 11 12 16 12 12 14 15 9 11 6 8 6 7 9 8 110 170 110 calm calm calm 130 220 210 250 250 200 180 190 200 230 200 230 210 200 220 170 180 170 Maximum 8-hour average 3.2 3.4 Time period for 8-H max. 0000- 0800 1400- 2200 Mean winds Time period 7.3 194 0000-2200 13 ------- SUNDAY, 25 APRIL 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 0.5 0.4 0.4 0.3 0.2 0.2 0.3 0.3 0.7 0.7 0.5 0.7 0.6 0.5 0.5 0.5 0.7 1.0 0.7 1.0 1.1 1.1 1.0 0.9 F.S. F.S. COURT COUNTY 2 4 HOUSE STATION 1.3 1.6 1.3 1.3 1.3 1.0 0.3 1.0 1.6 1.6 2.6 3.6 2.3 2.6 2.9 2.3 2.3 2.3 2.3 2.3 2.3 1.3 1.0 0.6 WIND SPEED 12 12 12 11 9 10 11 13 16 14 12 10 14 13 14 16 19 15 11 11 14 14 11 11 WIND DIRECTION 190 200 180 210 200 190 190 200 200 200 220 210 240 220 220 240 240 230 230 240 240 240 240 230 Maximum 8-hour average 0.9 2.6 Time period for 8-H max. 1600- 2400 1000- 1800 Mean winds Time period 13.2 23T 1000-2400 14 ------- MONDAY, 26 APRIL 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. F.S. 1 2 0.7 0.7 0.6 0.6 0.7 0.9 2.5 5.3 2.6 2.4 2.5 2.5 2.2 1.8 1.9 2.1 1.8 0.8 0.7 0.9 0.5 0.8 1.7 0.6 1.4 0.5 0.9 0.2 F.S. COURT 4 HOUSE 3.5 1.5 2.0 2.1 1.5 1.4 0.4 0.2 COUNTY STATION 0.6 0.6 1.0 1.3 1.0 1.3 1.3 2.0 1.6 2.0 1.6 1.6 1.6 1.6 2.0 2.0 2.3 1.0 1.3 1.6 WIND SPEED 10 5 4 5 6 6 5 7 10 9 12 13 14 15 12 14 14 12 8 6 6 9 17 9 WIND DIRECTION 240 300 300 330 330 320 310 310 340 360 320 330 330 300 310 340 320 340 330 330 340 030 030 040 Maximum 8-hour average 2.7 1.8 Time period for 8-H max. 0600- 1400 0900- 1700 Mean winds Time period 11.4 325 0600-1200 15 ------- TUESDAY, 27 APRIL 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 0.7 0.5 0.6 0.5 0.8 1.7 6.5 10.2 4.6 2.7 1.9 1.9 2.1 1.8 1.6 2.5 1.0 1.4 1.2 1.6 1.6 1.4 1.0 F.S. 2 0.2 0.2 0.3 0.2 0.3 0.7 2.1 2.9 1.0 1.1 0.6 0.7 0.7 0.6 0.6 0.9 1.2 1.3 0.9 1.3 1.4 1.1 0.6 0.6 F.S. COURT 4 HOUSE 0 0.1 0 0.2 0.3 1.4 5.6 7.5 4.3 3.2 2.6 2.0 1.9 1.9 1.8 2.0 2.8 1.2 1.3 1.5 2.3 1.4 0.7 0.4 COUNTY STATION 1.3 1.0 1.0 1.0 1.0 1.3 2.9 3.6 2.3 2.9 cal 4.2 2.3 2.3 1.3 1.6 1.6 1.0 1.0 0.6 1.0 0.6 1.0 0.6 WIND SPEED 8 3 4 3 5 4 5 7 8 9 7 8 10 10 10 10 4 4 5 6 7 8 7 10 WIND DIRECTION 040 090 350 060 060 040 040 020 020 310 280 260 260 300 220 270 290 060 360 360 340 040 040 050 Maximum 8-hour average 4.0 1.2 3.6 3.0 Time period for 8-H max.0500- 0500- 1300 1300 0600- 0600- 1400 1400 Mean winds Time period 7.6 329 0500-1400 16 ------- WEDNESDAY, 28 APRIL 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 0.5 0.3 0.3 0.4 0.6 1.2 7.3 6.5 4.3 3.9 2.3 2.7 2.3 2.9 2.8 2.0 2.0 3.2 4.3 2.7 2.6 1.3 F.S. 2 0.6 0.6 0.6 0.6 0.6 0.7 1.4 1.1 1.0 1.0 1.1 0.7 0.8 1.1 0.9 1.0 0.9 0.7 0.9 1.3 1.9 1.8 1.2 0.9 F.S. COURT 4 HOUSE 0.3 0.4 2.1 3.9 2.5 2.6 2.3 2.3 1.9 2.3 1.7 2.7 1.6 1.4 1.7 2.7 2.0 1.9 1.2 COUNTY STATION 0.6 0.6 0.6 0.3 0.6 2.0 3.9 5.9 2.9 2.6 cal 2.6 2.6 2.0 2.3 6.8 4.9 4.6 3.9 3.9 4.2 3.9 2.6 1.0 WIND SPEED 10 6 8 6 6 8 10 8 8 8 3 7 9 4 5 7 5 6 4 5 4 4 calm(O) 8 WIND DIRECTION 070 080 080 070 080 090 080 060 050 040 050 360 020 270 100 140 120 130 180 120 120 100 calm 360 Maximum 8-hour average 3.6 1.2 2.5 4.4 Time period for 8-H max. Mean winds Time period 0400- 1200 1500- 2300 0600- 1500- 1400 2300 5.8 77 0400-2300 17 ------- THURSDAY, 29 APRIL 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 0.9 0.9 0.7 0.7 0.7 1.5 6.1 11.5 6.5 3.5 2.8 2.7 2.2 2.1 1.5 1.6 1.0 0.8 2.0 3.8 4.6 4.2 2.4 F.S. 2 0.6 0.6 0.5 0.5 0.6 0.7 1.5 1.8 1.3 0.9 0.7 0.7 0.7 0.9 1.0 1.1 0.7 0.9 2.2 2.2 2.5 2.6 2.1 F.S. COURT 4 HOUSE 0.8 0.4 0.2 0.2 0.2 0.6 2.8 5.3 3.5 3.0 0.9 1.6 1.5 1.8 1.1 COUNTY STATION 0.6 0.6 0.6 0.3 0.6 1.6 2.0 cal 6.3 6.0 6.6 8.1 5.8 4.3 4.0 4.0 4.3 4.0 3.2 2.0 WIND SPEED 10 15 11 9 10 6 7 10 9 5 8 5 10 10 9 6 6 5 5 calm(O) 3 4 4 5 WIND DIRECTION 040 070 060 070 070 070 070 070 070 020 100 130 200 230 230 210 240 230 140 calm 130 090 090 120 Maximum 8-hour average 4.7 2.1 5.6 Time period for 8-H max. 0600- 1400 1900- 0300 1200- 2000 Mean winds Time period 5.9 136 0600-0300 18 ------- FRIDAY, 30 APRIL 76 CONCENTRATIONS (mg/in ) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 0.9 0.6 06 0.6 0.4 0.9 2.5 4.4 3.1 2.5 2.5 1.3 1.9 2.1 2.7 2.9 2.9 1.5 1.1 0.9 1.1 1.1 1.0 0.9 F.S. 2 1.0 1.0 1.1 0.9 0.8 0.7 1.2 1.6 1.2 1.0 0.5 0.3 0.3 0.3 0.5 0.6 0.7 0.6 0.4 0.3 0.3 0.3 0.2 0.3 F.S. COURT 4 HOUSE 0.2 0 0 0.2 1.1 2.9 3.9 3.2 3.5 3.1 3.0 3.0 4.4 6.2 2.9 0.5 1.7 0.7 1.7 0.4 1.3 0.3 1.2 0.3 1.1 0.3 0.9 COUNTY STATION 1.2 0.9 1.2 0.9 1.4 2.3 4.6 6.0 7.8 8.3 8.8 9.2 6.3 8.6 8.1 8.9 9.5 4.6 2.9 3.5 2.3 1.7 1.7 1.7 WIND SPEED 4 5 3 3 7 5 7 7 6 5 5 10 12 7 8 8 7 5 7 10 8 8 7 10 WIND DIRECTION 110 160 180 190 220 160 140 180 180 180 190 190 210 180 170 190 160 180 180 200 170 170 170 160 Maximum 8-hour average 2.6 1.1 3.8 8.5 Time period for 8-H max. Mean winds Time period 0700- 0100- 0200- 0900- 0900- 1500 0900 1000 1700 1700 7.3 182 0700-1700 19 ------- SATURDAY, 1 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 0.9 0.8 0.8 0.9 0.9 1.0 1.2 1.2 1.6 1.8 1.7 1.7 1.6 1.2 1.5 1.4 1.3 1.2 1.9 2.6 2.3 1.5 1.6 F.S. 2 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.5 0.4 0.6 0.8 0.8 0.8 0.9 0.9 1.4 1.5 1.4 1.1 1.2 F.S. 4 0.4 0.3 0.2 0.1 0.1 0.1 0.3 0.3 0.6 1.0 1.1 1.0 1.1 0.8 0.9 1.1 0.8 0.9 0.8 1.1 1.3 1.1 0.5 0.6 COURT HOUSE 1.4 1.2 0.9 0.9 0.7 0.8 1. 1.5 2.5 3.4 4.3 4.0 3.0 2.7 2.3 1.9 2.0 1.7 1.7 3.7 4.6 3.6 2.1 2.6 COUNTY STATION 0.9 0.3 0.3 0.3 0.9 0.9 1.4 2.0 2.6 3.2 4.3 3.7 3.7 4.3 2.9 2.6 3.2 2.3 2.6 1.7 2.0 4.3 3.5 2.3 WIND SPEED 4 7 6 8 10 7 8 12 12 10 10 13 18 15 16 17 12 15 9 6 4 6 3 3 WIND DIRECTION 140 140 130 130 150 180 170 200 210 220 240 220 220 220 220 230 230 210 200 090 110 200 250 300 Maximum 8-hour average 2.3 1.7 1.0 3.0 3.5 Time period for 8-H max. 1900- 0300 1400- 0300 1900- 0300 or 1400- 2200 0800- 0900- 1600 1700 Mean winds 9.5 220 20 ------- SUNDAY, 2 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 2.7 3.2 2.2 1.8 1.9 2.1 2.7 2.6 2.7 2.5 1.8 1.8 1.2 1.8 1.7 1.6 1.6 1.4 1.5 1.6 1.6 1.5 1.3 1.1 F.S. 2 1.4 3.5 1.7 1.0 1.1 1.0 1.5 1.3 1.1 0.9 0.9 0.8 0.7 0.9 0.7 0.8 0.7 0.9 1.1 1.2 1.3 1.1 0.8 0.6 F.S. 4 1.0 1.3 1.1 0.5 0.5 0.9 0.6 0.9 1.2 0.8 0.8 0.8 0.7 0.7 0.6 0.8 0.9 0.9 0.9 1.0 1.0 1.0 1.0 0.3 COURT HOUSE 1.3 2.3 1.7 1.0 1.0 0.9 1.2 1.1 1.2 0.9 0.9 1.3 0.9 0.9 0.8 0.8 0.7 0.6 1.1 1.2 1.0 0.9 0.6 0.2 COUNTY STATION 2.0 2.3 1.7 0.9 0.9 0.9 1.4 1.2 1.2 1.2 2.3 2.3 2.3 3.2 2.6 2.3 2.6 2.6 2.6 2.9 3.2 2.0 1.7 1.2 WIND SPEED 5 3 3 calm(O) 5 3 4 3 4 2 4 6 10 10 8 9 12 12 9 9 10 9 9 9 WIND DIRECTION 010 340 240 calm 010 060 340 080 090 100 140 140 270 210 250 230 230 230 220 230 240 240 230 250 Maximum 8-hour average 2.4 1.6 0.9 1.3 2.8 Time period for 8-H max. Mean winds Time period 0000- 0000- 0800 0800 0100- 0900 or 1500- 2300 0000- 0800 1300- 2100 6.3 127 0000-2300 21 ------- MONDAY,3 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-9000 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 0.9 0.8 0.6 0.6 0.7 1.2 2.8 4.7 3.5 3.1 3.1 2.5 2.1 2.4 2.9 2,5 4.8 1.3 2.2 2.4 1.9 1.8 1.8 1.5 F.S. 2 0.6 0.4 0.3 0.3 0.3 0.9 1.8 1.8 1.0 0.7 1.3 0.7 cal 0.6 0.8 1.0 2.1 0.8 1.1 1.0 0.9 1.0 1.2 1.0 F.S. 4 0.1 0 0 0.2 0.0 0.2 1.1 3.0 1.5 0.9 0.6 0.5 0.5 0.4 0.9 0.9 0.8 0.5 0.8 0.7 0.4 0.8 0.9 0.7 COURT HOUSE 0.2 0.1 0 0 0.1 0.6 3.5 6.2 4.4 5.6 4.5 1.0 3.9 2.0 4.0 5.3 6.7 1.7 2.2 7.2 2.7 1.5 1.3 0.7 COUNTY STATION 1.1 1.2 0.6 0.9 1.2 2.6 6.3 cal 2.6 1.4 2.0 1.7 2.3 4.0 0.9 0.9 0.9 0.9 WIND SPEED 5 5 4 5 5 6 9 10 8 13 7 14 12 9 8 9 8 10 8 14 8 8 4 7 WIND DIRECTION 250 220 230 220 230 230 250 250 270 290 280 310 290 340 290 300 340 340 320 330 340 350 330 Maximum 8-hour average 3.0 1.1 1.1 4.1 Time period for 8-H max. Mean winds Time period 0700- 1500 0400- 1200 or 1500- 2300 0400- 1700 or 1200- 2000 8.9 297 0400-2300 22 ------- TUESDAY, 4 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 1.4 1.1 1.0 0.9 1.1 1.8 4.5 5.9 3.9 3.3 3.2 3.2 2.8 2.7 cal 3.5 2.6 1.4 1.0 2.6 2.7 2.4 1.7 0.9 F.S. 2 0.7 0.7 0.6 0.5 0.7 1.4 2.7 2.0 1.3 1.2 1.0 1.1 1.1 1.1 cal 1.7 1.2 0.8 0.7 1.2 1.5 1.3 0.8 0.7 F.S. 4 0.8 0.7 0.1 0.2 0.3 1.2 2.0 0.3 0.4 0.7 0.5 0.6 0.4 0.4 0.2 0.7 0.7 0.3 0.7 1.6 1.6 1.1 0.7 0.3 COURT HOUSE 0.5 0.2 0.3 0.3 0.7 1.3 0.5 0.8 5.0 5.1 6.2 5.7 4.3 2.7 cal 3.0 3.2 1.7 1.3 1.5 1.4 1.0 1.2 0.7 COUNTY STATION 0.9 0.6 0.6 0.6 0.6 1.2 2.6 2.9 2.0 2.6 2.3 2.0 1.7 1.7 2.0 2.3 7.8 2.9 3.5 2.3 2.3 1.7 1.2 0.6 WIND SPEED 6 6 6 10 6 6 8 10 12 10 8 7 6 9 4 7 3 6 6 4 5 5 5 4 WIND DIRECTION 340 340 360 350 360 010 350 020 030 050 320 350 040 070 280 270 230 190 180 180 170 150 170 170 Maximum 8-hour average 3.7 1.5 0.9 4.4 3.1 Time period for 8-H max. 0600- 0500- 1900- 1400 1300 0300 0800- 1300- 1500 2100 Mean winds 7.0 110 Time period 0600-2100 23 ------- WEDNESDAY, 5 MAY 76 CONCENTRATIONS (mg/m3) TIME (EOT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 Maximum 8-hour average F.S. 1 0.8 1.0 0.6 0.6 0.6 1.0 3.2 2.7 1.2 0.9 1.0 0.9 1.4 0.7 0.9 1.5 1.5 0.2 1.5 1.4 F.S. 2 0.4 0.3 0.3 0.3 0.3 0.3 0.4 0.8 0.8 0.6 0.2 0.3 0.2 0.2 0.2 0.2 0.2 0.2 0.4 0.4 0.2 0.5 F.S. 4 0.2 0.2 0.2 0.3 0.3 1.1 1.6 3.0 1.4 1.2 0.8 0.9 0.7 0.7 0.7 0.7 0.4 0.6 1.0 0.5 0.4 0.2 0.5 1.3 COURT HOUSE 0.7 0.7 0.8 0.8 0.9 0.9 1.0 1.1 1.2 1.7 1.5 0.7 0.6 0.5 COUNTY STATION 0.3 0.3 0.6 0.9 0.9 2.0 5.5 6.9 6.0 5.5 cal 7.2 6.3 6.3 5.5 5.8 5.2 1.7 1.7 2.3 2.3 0.9 0.6 0 6.3 WIND SPEED 3 calm 4 3 calm 4 5 10 13 11 10 10 12 8 14 10 12 10 6 6 7 8 9 6 WIND DIRECTION 150 calm 150 180 calm 130 180 210 220 210 200 220 210 180 190 180 200 210 180 170 170 170 170 180 Time period for 8-H max. Mean winds Time period 0500- 1300 0100- 0900 0500- 1300 06CO- 1400 or 0700- 1500 9.2 196 0500-1400 24 ------- THURSDAY, 6 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. F.S. F.S. 1 2 4 0.1 0 0.1 0.1 0.1 1.5 2.0 2.4 1.8 1.7 1.6 1.3 1.0 1.2 1.4 1.5 1.8 0.6 1.7 1.1 2.3 1.4 2.4 1.2 1.7 0.6 0.8 0.3 0.5 COURT HOUSE 0.4 0.5 0.5 0.5 0.7 1.2 4.3 5.7 3.6 2.6 2.5 2.1 2.1 1.6 2.0 2.9 3.3 1.2 1.5 1.5 1.2 1.2 0.5 COUNTY STATION 0 0 0 0 0 2.3 1.4 5.2 5.2 4.9 6.6 5.8 6.9 4.6 4.9 5.8 6.3 2.9 2.9 2.6 2.3 1.4 0.9 0.6 WIND SPEED 7 7 10 7 5 4 3 8 9 11 11 11 9 9 10 13 10 8 6 6 6 5 10 8 WIND DIRECTION 170 180 200 190 180 320 240 240 220 230 230 200 180 200 160 200 189 180 180 170 140 150 190 180 Maximum 8-hour average Time period for 8-H max. 1.7 0500- 1300 3.1 0600- 1400 5.7 0900- 1200 Mean winds Time period 9.0 217 0500-1700 25 ------- FRIDAY, 7 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. F.S. 1 2 0.2 0.1 0.1 0.1 0.1 0.2 0.3 1.3 0.6 0.7 0.8 0.7 0.7 0.7 1.0 1.3 1.8 0.7 1.5 0.8 1.7 1.3 1.9 0.9 3.5 1.0 1.6 1.0 1.5 1.4 F.S. 4 0.1 0 0.1 0 0 0.4 1.4 2.0 1.9 1.3 1.3 1.8 1.4 1.3 1.7 1.6 1.7 1.6 1.5 2.3 1.5 1.6 1.4 1.3 COURT HOUSE 0.4 0.6 0.6 0.3 0.5 0.4 2.9 4.4 3.7 3.2 3.2 3.1 3.7 2.9 3.2 4.3 5.8 2.6 2.7 2.0 1.8 2.1 2.5 COUNTY STATION 0.3 0.9 0.6 0.9 0.9 2.6 3.2 8.9 7.8 7.2 cal 9.8 5.8 2.3 2.6 5.2 4.0 4.6 4.6 4.0 4.0 3.7 4.0 1.7 WIND SPEED 9 7 8 5 8 8 10 10 9 12 11 11 13 12 8 8 7 7 4 6 6 4 3 6 WIND DIRECTION 190 210 220 190 190 210 190 230 220 240 220 260 280 280 260 280 230 250 300 240 220 310 300 360 Maximum 8-hour average Time period for 8-H max. Mean winds Time period 1.1 1.7 4.1 6.6 1600- 1400- 0900- 0700- 2400 2200 1700 1500 8.2 259 0700-2400 26 ------- SATURDAY, 8 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 1.2 1.1 1.2 1.4 2.1 2.3 3.2 3.8 3.9 3.9 4.7 3.5 3.0 2.6 3.4 3.0 2.1 2.1 2.7 3.5 4.0 4.1 3.0 2.5 F.S. 2 0.8 0.8 0.6 0.7 0.7 0.8 0.9 1.2 1.4 1.5 1.4 1.3 1.3 1.7 2.0 1.3 1.2 1.0 1.0 1.3 2.1 2.5 2.8 3.5 F.S. 4 0.4 0.3 0.2 0.2 0.2 0.0 0.1 0.2 0.5 0.6 0.8 0.7 0.2 0.7 0.6 0.7 0.5 0.2 0.1 0.8 1.2 2.4 2.7 2.9 COURT HOUSE 1.9 1.0 0.4 0.4 0.4 0.8 0.9 1.2 1.9 1.6 2.9 2.3 2.2 2.0 1.7 2.0 1.8 1.4 1.5 1.4 1.8 2.6 3.4 3.8 COUNTY STATION 1.2 1.2 0.9 0.9 0.9 0.9 1.4 1.4 1.4 2.0 2.6 2.3 2.0 2.3 2.3 2.9 2.3 2.3 2.6 3.5 3.5 4.0 3.7 3.7 WIND SPEED 10 8 8 9 8 13 12 11 15 12 11 12 9 10 9 9 8 8 5 3 calm(O) calm(O) calm(O) 3 WIND DIRECTION 040 050 050 060 060 040 060 070 060 050 060 070 050 050 050 050 040 070 060 110 calm calm calm 310 Maximum 8-hour average Time period for 8-H max. Mean winds Time period 3.6 0700- 1500 3.7 2.1 3.2 3.6 2000- 2000- 2000- 2000- 0400 0400 0400 0400 6.0 61 0700-0400 27 ------- SUNDAY, 9 MAY 76 Maximum 8-hour average CONCENTRATIONS (mg/m3) TIME (EOT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 1.8 3.5 3.7 4.5 2.7 1.8 2.2 2.4 2.4 2.1 1.8 1.3 1.1 1.2 1.2 0.8 0.7 1.0 1.3 1.7 2.2 1.6 1.6 1.7 F.S. 2 4.9 3.7 5.3 4.5 3.6 3.0 2.4 1.2 1.1 1.1 1.0 0.9 0.8 0.8 0.9 0.9 0.8 0.8 0.8 1.2 1.2 1.4 1.2 1.0 F.S. 4 2.5 1.5 1.5 2.8 1.2 1.2 0.8 0.8 0.9 1.0 0.9 0.9 0.9 0.7 0.8 0.8 0.8 0.9 1.0 1.3 1.6 1.5 1.2 0.8 COURT HOUSE 3.0 2.0 4.3 4.9 2.6 1.8 1.6 1.6 2.0 1.3 1.2 1.5 1.5 1.5 1.6 1.5 1.4 1.6 1.4 1.8 1.3 1.2 1.3 0.8 COUNTY STATION 3.2 2.3 4.6 3.7 2.6 2.0 1.7 2.0 2.0 2.3 2.0 2.3 2.9 2.0 2.3 3.2 3.7 3.5 3.5 3.2 2.9 2.6 1.7 0.9 WIND SPEED calm(O) calm(O) calm(O) calm(O) calm(O) calm(O) calm(O) 6 6 5 3 8 5 3 5 4 5 7 6 4 4 calm(O) calm(O) calm(O) WIND DIRECTION 080 060 060 100 130 030 140 250 240 300 180 210 180 230 calm calm calm 2.9 1.9 1.5 1.7 Time period for 8-H max. 0100- 2000- 0000- 2000- 0900 0400 0800 0400 or or 0400- 0400- 1200 1200 Mean winds Time period 3.1 2000- 0400 or 1400- 2200 2.9 2000-2200 136 28 ------- MONDAY, 10 MAY 76 Maximum 8-hour average Time period for 8-H max. Mean winds Time period CONCENTRATIONS (mg/m3) TIME (EOT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 1.7 1.1 1.1 1.6 1.1 2.5 8.0 9.6 3.4 2.8 2.8 1.7 2.1 3.0 2.5 2.2 1.0 1.6 2.3 3.5 2.4 2.4 3.4 F.S. 2 0.9 1.0 0.6 0.7 0.7 0.9 2.4 2.9 1.5 0.9 0.6 0.6 0.4 0.5 0.4 0.8 0.8 0.6 0.9 1.3 1.7 1.9 1.5 1.5 F.S. 4 0.7 0.4 0.3 0.3 1.3 3.2 4.6 4.8 2.0 1.5 1.1 0.7 0.7 0.7 0.6 0.5 0.5 0.0 0.1 0.0 1.3 0.4 0.1 0.0 COURT HOUSE 0.7 0.7 0.7 0.9 1.8 3.4 7.1 8.4 4.9 3.9 3.7 3.2 2.2 2.2 1.9 2.9 1.8 1.8 1.7 1.8 1.0 0.7 0.5 COUNTY STATION 1.2 1.2 1.4 1.2 1.4 4.9 7.2 8.9 8.3 8.3 10.1 9.2 8.9 6.0 cal cal 8.6 2.9 2.3 3.2 WIND SPEED calm(O) 4 calm(O) calm(O) calm(O) calm(O) 3 3 8 6 6 5 6 8 7 8 8 8 4 calm(O) 3 3 3 calm(O) WIND DIRECTION calm 140 calm calm calm calm 050 220 250 240 200 180 140 190 240 230 210 220 190 calm 130 130 150 calm 3.8 0600- 1400 1.3 2.4 4.6 8.3 0100- 0400- 0500- 0700- 0900 1200 1300 1500 4.0 189 0100-1500 29 ------- TUESDAY, 11 MAY 76 Maximum 8-hour average Time period for 8-H max. Mean winds Time period CONCENTRATIONS (mg/m3) TIME (EOT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 1.3 0.3 0.1 0.0 0.1 0.4 2.7 6.1 3.6 3.1 3.5 2.2 2.7 2.1 2.3 3.5 2.3 2.0 2.1 2.5 2.4 2.4 2.0 1.4 F.S. 2 1.0 0.5 0.2 0.2 0.1 0.1 0.5 2.2 1.2 1.1 1.0 F.S. 4 2.9 1.9 1.3 1.1 1.2 1.3 2.8 4.9 1.8 1.9 2.2 2.2 1.8 1.2 1.1 1.9 1.7 0.6 1.1 0.6 0.6 0 1.0 0.5 COURT HOUSE 0.3 0.4 0.3 0.3 0.4 0.8 3.4 3.7 3.3 2.5 3.3 3.4 2.4 2.4 2.4 4.9 1.4 1.5 1.3 1.5 1.4 0.8 0.8 COUNTY STATION cal 8.1 9.2 9.2 8.1 6.3 6.9 5.8 3.5 1.7 0.6 0 4.6 2.9 1.7 1.2 WIND SPEED 4 6 6 6 3 4 5 8 3 5 6 7 10 11 11 12 8 7 5 6 5 4 4 5 WIND DIRECTION 140 140 170 150 150 140 230 270 250 240 240 200 200 240 230 270 250 280 320 230 180 150 180 220 3.3 0600- 1400 2.1 3.4 7.1 0500- 0600- 0900- 1300 1400 1700 7.1 219 0300-1200 30 ------- WEDNESDAY, 12 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) Maximum 8-hour average Time period for 8-H max. Mean winds Time period F.S. 1 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 1.0 1.0 1.2 2.3 5.2 13.3 12.3 7.6 5.4 3.6 3.5 3.4 3.3 3.2 3.2 3.6 2.4 2.4 6.8 0400- 1200 F.S. 2 F.S. 0.4 0.3 0 0 1.0 2.2 3.3 3.7 2.2 1.4 1.9 1.9 2.6 3.3 COURT HOUSE 0.7 0.4 0.4 1.7 2.4 2.8 2.5 1.2 0.6 COUNTY STATION 5.2 1300- 2100 WIND SPEED WIND DIRECTION 1.2 0.6 0.6 0.6 1.7 2.9 1.7 5.2 2.9 1.7 1.7 2.3 4.0 4.6 5.2 6.9 8.1 3.5 4.0 4.6 4.6 2.3 1.2 0.6 3 3 calm(O) calm(O) calm(O) 3 4 4 7 7 5 6 8 8 9 9 7 8 5 3 5 calm(O) calm(O) 4 220 180 calm calm calm 270 330 270 070 320 250 310 300 290 200 240 230 220 230 130 140 calm calm 110 5.4 249 0400-2100 31 ------- THURSDAY, 13 MAY 76 Maximum 8-hour average Time period for 8-H max. Mean winds Time period CONCENTRATIONS (mg/m3) TIME (EOT; 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. F.S. F.S. 124 1.5 2.1 0.5 4.4 4.8 3.5 3.5 3.5 2.2 1.8 2.4 2.3 2.2 2.1 1.2 1.0 0.2 1.0 0.7 0.3 1.1 0.6 0.2 1.0 0.4 0.1 0.2 0.1 0 0.1 000 COURT HOUSE 0.4 0.2 0.1 0.1 0.8 2.5 2.7 2.8 4.0 4.3 2.9 2.6 2.4 2.0 2.0 1.6 1.6 0.5 0.6 0.7 0.7 0.4 0.1 0.1 COUNTY STATION 0.6 0.6 0.6 0.8 0.9 2.9 8.1 11.2 7.2 4.9 4.9 3.2 5.5 4.3 4.9 5.8 4.3 1.4 1.4 1.2 0.6 0.3 0.6 0.9 WIND SPEED 4 3 4 calm(O) 3 4 5 9 6 5 9 8 9 7 7 14 12 13 8 8 9 10 8 8 WIND DIRECTION 140 130 120 calm 110 080 070 090 040 090 080 120 120 100 120 140 130 120 140 160 150 160 140 150 3.3 3.0 6.2 0600- 0500- 0600- 1400 1300 1400 7.0 89 0500-1400 32 ------- FRIDAY, 14 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 1.1 1.1 0.9 0.7 0.6 1.1 3.7 6.4 4.3 3.5 3.8 3.6 3.5 2.9 3.1 3.2 3.1 1.5 0.8 0.9 0.9 0.8 0.2 0 F.S. 2 0.6 0.6 0.6 0.5 0.4 0.4 0.6 0.8 0.7 0.9 0.4 0.5 0.6 0.5 0.5 0.5 0.4 0.5 0.7 0.4 0.2 0.2 0.1 0 F.S. 4 0.1 0.2 0.2 0.2 0.1 0.5 1.5 2.6 2.2 1.7 2.0 2.4 2.3 2.0 3.3 3.1 3.0 2.2 2.0 1.5 0.7 0.6 0.5 0 COURT HOUSE 0.1 0.0 0.1 0.2 0.2 0.3 1.7 3.0 3.6 2.5 2.9 2.7 2.6 1.8 2.2 2.2 3.0 1.0 1.0 1.1 0.8 0.7 0.4 COUNTY STATION 0.3 0.3 0.3 0.3 0.3 1.4 2.9 5.8 4.9 5.2 6.0 5.8 7.8 6.0 cal 5.5 4.3 1.7 1.7 1.7 1.4 0.9 0,6 0 WIND SPEED 7 6 8 7 7 4 9 10 11 13 10 12 9 12 11 12 13 14 10 18 8 12 12 12 WIND DIRECTION 130 140 140 150 170 140 160 150 170 170 180 200 170 200 180 120 190 130 130 140 140 150 140 150 Maximum 8-hour average 4.0 Time period for 8-H max. 0600- 1400 Mean winds Time period 0.6 2.4 2.7 5.9 0600- 1000- 0900- 0700- 1400 1800 1700 1800 11.5 176 0700-1700 33 ------- SATURDAY, 15 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 0.2 0.2 0 0.1 0 0.3 0.5 0.8 1.1 1.4 1.4 1.4 2.0 1.4 1.0 2.0 3.1 3.0 4.1 3.6 3.2 2.3 2.4 1.6 F.S. 2 0.1 0 0.1 0 0.1 0.1 0.1 0.2 0.3 0.1 0.2 0.2 0.3 0.3 0.3 0.5 1.4 1.7 1.3 1.7 1.6 1.0 1.0 0.7 F.S. 4 0.2 0.2 0 0.1 0 0.1 1.3 0.6 0.9 0.9 1.1 1.3 1.6 1.3 0.9 1.7 2.4 1.9 1.6 1.7 1.5 1.0 0.2 0.9 COURT HOUSE 0.2 0.2 0.1 0.1 0.1 0.2 0.5 0.5 0.8 1.0 0.9 1.2 1.4 1.1 1.4 2.7 2.8 2.1 2.0 2.2 2.1 1.8 2.0 2.2 COUNTY STATION 0 0 0 0 0 0.3 0.6 0.9 1.2 1.2 1.2 1.7 2.3 1.7 2.6 4.6 4.9 4.6 4.6 4.0 2.6 2.3 2.6 0.6 WIND SPEED 10 11 12 11 9 12 14 13 14 14 15 15 7 15 7 5 4 6 5 4 7 5 3 7 WIND DIRECTION 140 140 140 150 160 150 140 140 150 160 160 160 120 180 200 110 100 100 100 090 090 090 070 050 1.3 1.6 2.2 3.8 1600- 1200- 1500- 1500- 2400 2000 2300 2300 4.9 94 1500-2300 34 ------- SUNDAY, 16 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 1.0 0.6 0.3 0 0 0.3 0.5 0.4 0.4 0.5 1.0 1.1 1.1 1.3 1.2 1.1 1.2 1.4 1.5 1.2 0.9 0.9 0.7 0.0 F.S. 2 0.5 0.3 0.1 0 0 0.2 0.2 0.3 0.2 0.3 0.3 0.4 0.6 0.8 0.8 0.8 0.9 0.9 1.1 1.0 0.5 0.4 0.3 0.2 F.S. 4 0.6 0.3 0.2 0.1 0 0.3 0.5 0.3 0.8 0.9 0.8 1.3 1.1 1.2 1.1 1.3 1.4 1.5 1.2 0.8 0.9 1.3 0.2 0.2 COURT HOUSE 1.2 0.7 0.5 0.4 0.1 0.1 0.4 0.6 0.9 0.8 0.8 0.9 0.9 0.5 0.7 0.7 0.7 0.9 1.0 0.7 0.6 0.4 0.4 0.2 COUNTY STATION 0.3 0.6 0.3 0 0 0 0.6 0.9 1.4 1.4 1.7 2.0 1.0 1.4 2.3 2.6 2.3 1.4 1.7 1.2 0.6 0.3 0 0 WIND SPEED 7 8 5 12 4 4 7 11 10 11 12 11 10 14 13 10 10 10 8 7 10 11 11 8 WIND DIRECTION 090 120 130 130 170 140 190 200 230 220 240 230 230 230 220 220 230 200 210 170 170 180 180 210 Maximum 8-hour average Time period 1.3 Time period for 8-H max. 1200- 2000 0.8 1.3 0.8 1200- 1100- 1100- 2000 1900 1900 1.9 0900- 1700 or 1100- 1900 0900-1900 35 ------- MONDAY, 17 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 0.1 0.1 0.1 0.1 0.6 3.5 5.7 2.8 2.1 2.7 2.3 2.6 1.9 2.2 2.6 2.9 1.6 1.5 1.6 1.8 1.6 1.6 1.1 F.S. 2 0.2 0.1 0.2 0.5 1.3 0.8 0.6 0.7 1.0 0.9 1.0 1.3 1.3 1.3 1.0 1.0 1.1 1.0 1.2 0.9 1.0 F.S. 4 0 0.1 0.2 0.1 0.6 1.2 2.5 3.1 2.2 2.2 2.4 2.3 2.4 2.3 2.2 2.1 2.7 2.1 2.3 2.3 2.5 2.2 2.1 2.2 COURT HOUSE 0.4 0.2 0.2 0.2 1.2 1.6 4.9 6.9 4.5 4.8 3.7 3.5 4.3 2.4 3.4 3.3 3.4 4.2 1.3 1.2 1.5 1.1 1.0 0.8 COUNTY STATION 0.3 0.6 0.9 0.3 0.9 2.6 8.3 7.2 7.5 cal 7.2 7.5 7.2 6.3 7.5 8.9 7.8 2.0 WIND SPEED 4 4 4 8 8 4 7 8 10 7 9 12 13 15 14 14 14 14 11 6 8 8 6 7 WIND DIRECTION 220 240 180 220 250 180 200 240 230 250 220 230 240 240 240 220 230 220 230 230 220 230 230 220 Maximum 8-hour average 3.0 1.2 2.4 4.4 7.5 Time period for 8-H max.0600- 1400- 0600- 0500- 0900- 1400 2200 1400 1400 1700 Mean winds 10.1 231 Time period 0600-1400 36 ------- TUESDAY, 18 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 0.1 0.7 3.0 7.3 3.9 2.3 2.0 1.8 2.2 1.5 3.3 3.2 1.3 0.7 0.9 0.9 0.9 1.0 0.9 0.6 F.S. 2 0.1 0.1 0.1 0.1 0.3 1.6 1.4 1.0 0.9 0.8 0.8 0.8 0.7 1.0 1.1 0.6 0.6 0.7 0.9 1.0 0.9 0.8 F.S. 4 0.5 0.2 0.3 0.1 0.7 2.9 4.2 3.4 2.1 1.8 1.7 2.1 1.0 0.3 0.3 0.3 COURT HOUSE 0.4 0.4 0.4 0.4 0.3 1.0 5.2 7.0 4.4 3.6 3.7 2.5 2.0 3.0 3.4 5.4 4.9 1.1 0.8 1.5 1.1 0.7 0.4 0.1 COUNTY STATION cal 7.2 5.2 1.4 1.2 1.4 1.4 0.3 0.6 0.3 WIND SPEED 7 4 calm(O) 3 4 5 4 6 9 9 12 13 15 12 7 13 15 16 13 6 4 4 6 4 WIND DIRECTION 240 220 calm 270 230 190 260 210 210 240 240 220 230 330 310 320 340 340 320 320 330 310 340 010 Maximum 8-hour average 3.0 1.0 2.4 3.9 Time Period for 8-H max.0700- 0600- 0600- 0600- 1500 1400 1400 1400 Mean winds 10.0 257 Time period 0600-1500 37 ------- WEDNESDAY, 19 MAY 76 CONCENTRATIONS (mg/m3) TIME (EOT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 0.1 0.2 0.1 0.9 1.1 4.3 6.5 2.4 1.7 2.3 1.7 1.8 1.8 1.6 2.1 1.9 1.0 0.2 0.3 0.4 0.8 0.7 0.4 F.S. 2 0.7 0.8 0.9 0.6 0.7 1.5 2.9 2.8 1.3 1.1 1.2 1.1 1.0 1.3 1.3 1.5 1.5 0.7 1.0 0.7 1.4 1.4 0.9 1.0 F.S. 4 0.2 0.1 0.1 0.5 1.0 2.9 2.4 2.0 1.8 2.0 1.5 1.7 2.1 1.8 1.5 2.1 0.8 1.3 1.7 1.7 1.5 1.3 1.2 COURT HOUSE 0.1 0.1 0.1 0.1 0.1 0.8 4.1 4.6 COUNTY STATION 0.3 0.3 0.3 0.3 2.6 4.0 3.7 2.0 3.2 2.0 1.2 1.4 2.6 1.7 2.9 2.9 2.0 1.4 1.4 2.0 1.2 0.3 0.6 WIND SPEED 5 4 6 4 6 4 6 8 11 12 11 15 14 15 15 13 11 15 14 5 6 4 6 3 WIND DIRECTION 290 270 270 260 260 270 270 280 260 240 280 280 270 270 270 270 280 250 260 280 290 220 300 240 Maximum 8-hour average 2.8 1.6 2.0 2.5 Time Period for 8-H max.0600- 0500- 0600- 1400 1300 1400 0500- 1300 Mean winds 11.1 269 Time period 0500-1400 38 ------- THURSDAY, 20 MAY 76 CONCENTRATIONS (mg/m3) TIME (EDT) 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 F.S. 1 0.1 0.2 0.3 0.6 3.4 10.5 12.8 2.8 1.5 1.3 1.0 0.8 0.5 0.7 0.9 F.S. 2 0.8 0.6 0.5 0.5 0.8 2.8 5.5 5.5 1.5 0.5 0.3 0.2 0.3 0.2 0.4 0.3 0.4 F.S. 4 0.5 0.2 0.6 0.9 1.5 4.4 3.4 1.7 2.0 1.9 2.1 1.7 1.6 1.8 1.8 2.0 1.3 1.9 COURT COUNTY HOUSE STATION 0.6 0.6 0.6 0.6 2.3 3.2 4.3 4.9 2.0 3.2 6.0 6.6 WIND SPEED 4 calm(O) 4 5 5 4 calm(O) 5 5 4 10 13 15 14 11 8 8 11 7 9 7 5 5 4 WIND DIRECTION 020 calm 300 270 090 240 calm 320 290 240 220 230 200 230 230 250 240 230 230 220 220 230 200 240 Maximum 8-hour average 3.7 2.2 2.3 Time Period for 8-H max.0500- 0100- 0600- 1300 0900 1400 Mean winds 6.7 268 Time period 0100-1400 39 ------- TECHNICAL REPORT DATA (Please read Instructions on the reverse before completing) 1. REPORT NO. EPA-600/4-77-013 3. RECIPIENT'S ACCESSIOI*NO. 4. TITLE AND SUBTITLE CARBON MONOXIDE LEVELS IN CHARLOTTE, NORTH CAROLINA 5. REPORT DATE February 1977 6. PERFORMING ORGANIZATION CODE 7. AUTHOR(S) Norman E. Hester and John Prince 8. PERFORMING ORGANIZATION REPORT NO. 9. PERFORMING ORGANIZATION NAME AND ADDRESS Environmental Monitoring and Support Laboratory Office of Research and Development U.S. Environmental Protection Agency Las Vegas, Nevada 89114 10. PROGRAM ELEMENT NO. 1AD606 11. CONTRACT/GRANT NO. 12. SPONSORING AGENCY NAME AND ADDRESS U.S. Enviornmental Protection Agency-Las Vegas, NV Office of Research and Development Environmental Monitoring and Support Laboratory Las Vegas, Nevada 89114 13. TYPE OF REPORT AND PERIOD COVERED Tech. Support Apr.-May 1976 14. SPONSORING AGENCY CODE EPA/600/07 15. SUPPLEMENTARY NOTES John Prince is an employee of Lockheed Electronics Co., 4220 South Maryland Parkway. Suite 120, Las Vegas, Nevada 89109 16. ABSTRACT Four temporary monitoring stations were set up in Charlotte, North Carolina during the months of April and May 1976. Results from the temporary stations were compared with data from the local monitoring station to determine if the local station was producing data representative of the city or of a localized hot spot. The maximum 8-hour averages of carbon monoxide data collected at this county station were found to be higher than those collected at the four temporary sites by factors of 1.4, 1.6, 2.7, and 3.3. Based on these results, it was concluded that the local station was not representative of the metropolitan area. 17. KEY WORDS AND DOCUMENT ANALYSIS DESCRIPTORS b.IDENTIFIERS/OPEN ENDED TERMS COSATl Field/Group Air pollution Carbon Monoxide Measurements Charlotte, North Carolina Mecklenburg County EPA Region VIII Air quality Monitoring 13B 07B, C 14B 13. DISTRIBUTION STATEMENT RELEASE TO PUBLIC 19. SECURITY CLASS (This Report) Unclassified 21. NO. OF PAGES 44 20. SECURITY CLASS (This page) Unclassified 22. PRICE EPA Form 2220-1 (9-73) ------- |