n 

U 

OCS Study 

MMS 96-0062 

Coastal Marine Institute 

Analysis of Ambient Pollutant 

Concentrations and Meteorological 

Conditions Affecting EPA Class I and II 

Areas in Southeastern Louisiana 

Volume I : Technical Report 

U.S. Department of the Interior 

Minerals Management Service 

Gulf of Mexico OCS Region 
OCS Study 

MMS 96-0062 

Coastal Marine Institute 

Analysis of Ambient Pollutant 

Concentrations and Meteorological 

Conditions Affecting EPA Class I and II 

Areas if Southeastern Louisiana 

Volume I : Technical Report 

Authors 

S. A. Hsu 

Prepared under MMS Contract 

14-35-0001-30660-19925 

by 

Coastal Studies Institute 

Louisiana State University 

Baton Rouge, Louisiana 70803 

Published by 

U .S. Department of the Interior New Orleans 

Minerals Management Service December 1996 

Gulf of Mexico OCS Region 
DISCLAIMER 

This report was prepared under contract between the Minerals Management Service (MMS) and the 

Coastal Studies Institute, Louisiana State University. This report has been technically reviewed by 

the MMS and approved for publication. Approval does not signify that the contents necessarily 

reflect the views and policies of the Service, nor does mention of trade names or commercial products 

constitute endorsement or recommendation for use. It is, however, exempt from review and 

compliance with MMS editorial standards. 

REPORT AVAILABILITY 

Extra copies of the report may be obtained from the Public Information Office (Mail Stop 5034) at 

the following address : 

U.S . Department of the Interior 

Minerals Management Service 

Gulf of Mexico OC S Region 

Attention: Public Information Office (MS 5034) 

1201 Elmwood Park Boulevard 

New Orleans, Louisiana 70123-2394 

Telephone Number: 1-800-200-GULF or 

504-736-2519 

CITATION 

Suggested citation : 

Hsu, S. A. 1996. Analysis of ambient pollutant concentrations and meteorological conditions 

affecting EPA Class I and II areas in southeastern Louisiana, Volume 1 : Technical Report. 

OCS Study MMS 96-0062. U.S . Dept. of the Interior, Minerals Management Service, Gulf 

of Mexico OCS Region, New Orleans, LA. 156 pp . 

FRONT COVER 

Coastal Studies Institute technician Bill Gibson inspecting the Gusier Island, Louisiana, SOZ and 

meteorological monitoring station, August, 1994. 

iii 
ABSTRACT 

Seasonal weather patterns over the northeast Gulf of Mexico can produce prolonged periods of 

onshore flow. Since areas of the coastlines and barrier islands of Louisiana, Mississippi, and Alabama 

have been designated as Class I and II by the EPA, there is concern that pollutants from Outer 

Continental Shelf (OCS) activities, such as petroleum drilling and production, may be acting to 

degrade these pristine environments. Three air quality and meteorological monitoring stations were 

deployed during the period of July through mid-September 1994 to measure ambient levels of SOZ 

and NOX as well as meteorological conditions. Two stations were in the Class I Breton National 

Wildlife Area while the third was in the Class II Delta National Wildlife Refuge of southeastern 

Louisiana. It was found that the majority of all measurements of S02 and NOX acquired during the 

period were less than 5 - 10 ppb. Concentrations in the Breton Refuge were generally higher than 

those measured in the Delta Refuge, with highest concentrations being from the north and northeast. 

In addition, distinct short-lived episodes of higher than average (for the data record) NO, 

concentrations were evident in the Breton data set. Radiosondes released throughout the study 

period reveal the average mixing height to be 600 - 700 m, well below the climatic average believed 

to prevail over our area during the summer. A method of estimating the offshore mixing height from 

surface temperature values is presented. Long-term monitoring is recommended to gain a better 

understanding of offshore pollutant transport, to delineate between OCS and onshore pollutant 

contributions, and to compare with the PSD increments for our area. 

v 
TABLE OF CONTENTS 

List of Figures 

List of Tables 

Acknowledgments 

Executive Summary 

Methodology 

Results and Discussion 

Recommendations 

References 

Page 

ix 

xiii 

3 

7 

95 

133 

137 

vii 
LIST OF FIGURES 

Figure Page 

1 Air quality and meteorological station deployed during the summer of 4 

1994. 

2 Calibration curves from Pass-A-Loutre air quality analyzers. 13 

3a July 1994 hourly SOZ concentrations at Gosier Island . 31 

3b August 1994 hourly SOZ concentrations at Gosier Island . 32 

3c September 1994 hourly SOZ concentrations at Gosier Island. 33 

3d July 1994 hourly wind speeds at Gosier Island and NUAA buoy 42007 . 34 

3e August 1994 hourly wind speeds at Gosier Island and NOAH buoy 35 

42007. 

3f September 1994 hourly wind speeds at Gosier Island and NOAH buoy 36 

42007. 

3g July 1994 hourly wind directions from Gosier Island and NOAA buoy 37 

42007. 

3h August 1994 hourly wind directions from Gosier Island and NOAH 38 

buoy 42007. 

3i September 1994 hourly wind directions from Gosier Island and NOAA 39 

buoy 42007 . 

3j July 1994 hourly air temperatures at Gosier Island and NOAA buoy 40 

42007. 

3k August 1994 hourly air temperatures at Gosier Island and NOAA buoy 41 

42007. 

31 September 1994 hourly air temperatures at Gosier Island and NOAA 42 

buoy 42007. 

3m July 1994 hourly pond data at Gosier Island (see text for explanation) . 43 

4a July 1994 hourly SOz concentrations at Breton Island . 44 

4b August 1994 hourly SOZ concentrations at Breton Island . 45 

4c September 1994 hourly S02 concentrations at Breton Island . 46 

4d July 1994 hourly NO concentrations at Breton Island . 47 

ix 
Figure Page 

4e August 1994 hourly NO concentrations at Breton Island . 48 

4f September 1994 hourly NO concentrations at Breton Island . 49 

4g July 1994 hourly NOZ concentrations at Breton Island . 50 

4h August 1994 hourly NOZ concentrations at Breton Island . 51 

4i September 1994 hourly NOZ concentrations at Breton Island . 52 

4j July 1994 hourly NO. concentrations at Breton Island . 53 

4k August 1994 hourly NO,, concentrations at Breton Island . 54 

41 September 1994 hourly NO, concentrations at Breton Island . 55 

4m July 1994 hourly air temperatures from Breton Island and NOAH buoy 56 

42007. 

4n August 1994 hourly air temperatures from Breton Island and NOAH 57 

buoy 42007. 

4o September 1994 hourly air temperatures from Breton Island and NOAH 58 

buoy 42007. 

4p July 1994 hourly atmospheric pressure from Breton Island and NOAA 59 

buoy 42007. 

4q August 1994 hourly atmospheric pressure from Breton Island and 60 

NOAH buoy 42007. 

4r September 1994 hourly atmospheric pressure from Breton Island and 61 

NOAA buoy 42007. 

4s July 1994 hourly relative humidity from Breton Island . 62 

4t August 1994 hourly relative humidity from Breton Island . 63 

4u September 1994 hourly relative humidity from Breton Island . 64 

Sa July 1994 hourly SOZ concentrations at PAL. 65 

Sb August 1994 hourly SOZ concentrations at PAL. 66 

Sc September 1994 hourly SOZ concentrations at PAL. 67 

Sd July 1994 hourly NO concentrations at PAL. 68 

Se August 1994 hourly NO concentrations at PAL. 69 

x 
Figure Page 

Sf September 1994 hourly NO concentrations at PAL. 70 

Sg July 1994 hourly N02 concentrations at PAL. 71 

Sh August 1994 hourly N02 concentrations at PAL. 72 

Si September 1994 hourly N02 concentrations at PAL. 73 

Sj July 1994 hourly NO,, concentrations at PAL. 74 

Sk August 1994 hourly NO,, concentrations at PAL. 75 

51 September 1994 hourly NO. concentrations at PAL. 76 

Sm July 1994 hourly wind speeds at PAL and NOAH stations GDIL1 and 77 

BURI,1 . 

Sn August 1994 hourly wind speeds at PAL and NOAA stations GDII,1 78 

and BURL 1 . 

So September 1994 hourly wind speeds at PAL and NOAH station GDII,I . 79 

Sp July 1994 hourly wind directions at PAL and NOAA stations GDII,I SO 

and BURL 1 . 

Sq August 1994 hourly wind directions at PAL and NOAA stations GDII.1 81 

and BURL 1 . 

Sr September 1994 hourly wind directions at PAL and NOAH station 82 

GDIL 1 . 

Ss July 1994 hourly air temperatures at PAL and NOAH stations GDII.1 83 

and BURL 1 . 

St August 1994 hourly air temperatures at PAL and NOAA stations 84 

GDEL I and BURL 1 . 

Su September 1994 hourly air temperatures at PAL and NOAH station 85 

GDII.1 . 

Sv July 1994 hourly atmospheric pressure at PAL and NOAA stations 86 

GDEL 1 and BURL 1 . 

Sw August 1994 atmospheric pressure at PAL and NOAH stations GDII.1 87 

and BURL 1 . 

Sx September 1994 hourly atmospheric pressure at PAL and NOAH station 88 

GDII.1 . 

xi 
Figure Page 

Sy July 1994 hourly relative humidity at PAL. 89 

Sz August 1994 hourly relative humidity at PAL. 90 

Saa September 1994 hourly relative humidity at PAL. 91 

6 NAAQS standards and maximum SOZ concentrations at PAL and Breton 99 

Island . 

7 July 1994 wind rose from Gosier Island . 105 

8 August 1994 wind rose from Gosier Island . 106 

9 September 1994 wind rose from Gosier Island . 107 

10 August 1994 wind rose at Gosier Island . 108 

11 Frequency distribution of NOZ (in ppb) at Breton Island during the 109 

period of 1 July to 26 September 1994 based on Gosier Island winds 

(1819 samples, 86.2% of possible record). 

12 Frequency distribution of SOZ (in ppb) at Breton Island for the months 110 

of July and August 1994 based on Gosier Island winds (887 samples, 

59.6% of possible record). 

13 July 1994 wind rose from PAL. 119 

14 August 1994 wind rose from PAL. 120 

15 July 1994 wind rose from PAL. 121 

16 August 1994 wind rose from PAL. 122 

17 Frequency distribution of NOZ concentration (in ppb) at PAL during the 123 

period of 1 July to 12 September 1994 (1574 samples, 89 .9% of possible 

record) . 

18 Frequency distribution of SOZ concentration (in ppb) at PAL during the 124 

period of 1 July to 12 September 1994 (1715 samples, 97 .9% of possible 

record) . 

19 Atmospheric profiles of potential temperature (8, X-line) and mixing 126 

ratio (q, o-line) versus height in m over our study area. 

xii 
LIST OF TABLES 

Table Page 

1 A Gosier Island SO, Precision Data 15 

1B Gosier Island SOZ Accuracy Data 16 

2A Breton Island SOz Precision Data 17 

2B Breton Island SOz Accuracy Data 17 

3A Breton Island NO. Precision Data 18 

3B Breton Island NOX Accuracy Data 20 

4A Pass-A-Loutre SOZ Precison Data 22 

4B Pass-A-Loutre SOZ Accuracy Data 23 

SA Pass-A-Loutre NO. Precision Data 24 

SB Pass-A-Loutre NOX Accuracy Data 26 

6 Percentage Data Return 29 

7 Radiosonde Launch Information 30 

8 U.S. Federal Primary and Secondary Ambient Air Quality Standards 96 

9 U.S. Federal PSD Concentration Increments 97 

10 Gosier Island Ogawa (SOZ) Passive Data 100 

11 Gosier Island Palmes (NOz) Passive Data 101 

12 Breton Island Daily SOz Maximums and Averages (ppb) 102 

13 Breton Island Daily NOZ Maximums and Averages (ppb) 103 

14 Breton Island 1994 Pollutant Maximums 104 

15 Events of Breton Island NOZ Concentrations > 18 .2 ppb 111 

16 Breton Island Ogawa (SOZ) Passive Data 114 

17 Breton Island Palmes (NOz) Passive Data 115 

18 Pass-A-Loutre Daily SOZ Maximums and Averages (ppb) 116 

19 Pass-A-Loutre Daily NOz Maximums and Averages (ppb) 117 

20 Pass-A-Loutre 1994 Pollutant Maximums 118 

21 Events of Pass-A-Loutre NOZ Concentrations > 8 .8 ppb 125 

22 Lifting Condensation Levels and Mixing Heights 129 

xiii 
ACKNOWLEDGMENTS 

The successful execution of this field measurement study would not have been possible 

without the involvement of several agencies . We would like to thank Ms. Elizabeth Souheaver of the 

U.S . Fish and Wildlife Service and Mr. Mike Windham and Mr Emil Leblanc of the Louisiana 

Department of Wildlife and Fisheries for allowing us to establish our stations at Gosier Island and 

Pass-A-Loutre, respectively . During the height of fishing season, Mr. Dennis Good provided space 

on board his charter houseboat Chandeleur Islander for our third station, as well as excellent 

hospitality and a safe haven for our field crew during rough offshore weather. Mr. Joey Landreneau, 

Mr. Mark Kimball, and Mr. Carl Nagle of Environmental Science and Engineering, Inc. supplied the 

air quality equipment and assisted in the station setup and maintenance. The field technicians of the 

Coastal Studies Institute (CSI) Field Support Group are to be commended for their logistic support 

during the entire field program; special recognition to Mr. Bill Cribson for his considerable efforts in 

keeping all three stations operational. Brian Blanchard of CSI was involved in the field servicing and 

later helped reduce the data and produce this document. Finally, we appreciate the cooperation and 

assistance of Dr. Jim Kendall, Dr. Bill Hutzell, and Mr. Bill Steorts of the Minerals Management 

Service, New Orleans, regarding this project. 
EXECUTIVE SUMMARY 
EXECUTIVE SUMMARY 

The U. S. Environmental Protection Agency (EPA) has designated sections of southern 

Mississippi and Alabama as Class I and II areas due to their status as National Seashores . Part of the 

Breton National Wildlife Area in the Chandeleur Islands of Louisiana provides protected haven for 

the abundant wildlife inhabiting these environments, and is also Class I. The Delta National Wildlife 

Refuge in the Mississippi River Delta is Class II . Having attained this ranking, these areas fall under 

the restrictions of the Prevention of Significant Deterioration (PSD) regulations of the Clean Air Act . 

Although the air quality is presumably quite clean at present, it is mandatory that pollutants 

transported into the areas do not lower the air quality beyond a specified significant increment. 

Offshore oil and gas production to the east and south of the Mississippi River Delta is 

currently very active and will likely increase in the future . Atmospheric releases of sulphur and 

nitrogen compounds are a natural by-product of the production processes. Since the National 

Seashores and Wildlife Refuges are coastally located, they are in a unique position in which they can 

be affected by land-based as well as offshore (Outer Continental Shelf) pollutant sources. 

To gain a better understanding of the current ambient levels of both SOZ and NO2, three air 

quality and meteorological monitoring stations were deployed during the period of July through midSeptember 1994. High pressure normally dominates over the area during this time, which can lead 

to air stagnation and in turn, higher pollutant levels . Two stations were established in the Breton 

National Wildlife Area and one at the headquarters of the Louisiana Wildlife and Fisheries at Pass-ALoutre, Louisiana (see Fig. 1). Measured parameters included SOZ, NO Z , air temperature, 

atmospheric pressure, relative humidity, and wind speed and direction. 

Analysis of the available data records shows that measured pollutant levels at all three stations 

were well below the National Ambient Air Quality Standard maximums. Allowable limits on 

pollutant concentrations applying to PSD Class I and II areas are increments with respect to a 

baseline concentration. Due to the unavailability of these baseline measurements combined with the 

relatively short and non-continuous record obtained in this program, direct comparisions with PSD 

increments were not valid. On the other hand, average and maximum concentrations of both SOZ and 

NOz were considerably higher at Breton Island than at Pass-A-Loutre. Furthermore, several distinct 

episodes of higher than average NO,, concentrations were evident in the Breton Island record . The 

data indicates that these short-lived (on the order of hours) events may be due to local sources rather 

than long distance transports. Highest concentrations of NOZ and SOZ at Breton Island during the 

study period were from the north and northeast, while at Pass-A-Loutre highest NOZ concentrations 

were observed from the northwest and southwest and highest SOZ from the north. For S02, the 

highest 3-hourly and daily concentration was 13 .3 ppb (f 6.4) and 2 .8 ppb (t 0.8) at Breton Island 

and 5.7 ppb (f 1 .5) and 1 .4 ppb (t 1 .6) at Pass-A-Loutre, respectively . The highest 3-hourly and 

daily NOZ concentrations were 31 ppb (f 5.6) and 12 ppb (f 12 .8) for Breton Island and 13 ppb (f 

1 .7) and 5 .1 ppb (f 3 .8) for Pass-A-Loutre, respectively . The majority of all hourly samples were 

less than 5 ppb. 

3 
Twelve atmospheric profiles (radiosondes) were obtained during the study period . It is shown 

that the average mixing heights are nearly identical to the average lifting condensation level (LCL). 

A method for estimating the LCL from surface temperatures is given with a root mean square error 

of approximately 70 m. Mixing heights over the marine area are found to be significantly lower than 

the previously accepted climatic mean. 

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Figure 1 . Air quality and meteorological stations deployed during the summer of 1994. 

4 
METHODOLOGY 
METHODOLOGY 

1 . Introduction 

During the 1994 summer months of July through mid-September, air quality and 

meteorological data was collected from three field stations located within the Mississippi River Delta 

and off the Louisiana coast in the Chandeleur Islands. In essence, this deployment was a repeat of 

our pilot study conducted during the summer of 1993 (see Hsu, 1995) but with a much more 

comprehensive measurement program. Details of the setup, equipment, calibration techniques and 

results, and data collected for each station is provided in the following sections. 

2. Equipment 

All three stations were originally designed to be equipped with the same suite of 

meteorological sensors and air quality analyzers; however frequent operational problems and 

malfunctions during the deployment resulted in the use of several different brands of instrumentation. 

In general, the minimum detectable threshold for all air quality analyzers used was 1 ppb. All data 

was stored on site via Campbell CR10 dataloggers. These dataloggers utilize a 10-second scan rate 

and were programmed for 5-minute averages (30 samples). Depended on the parameter, average 

values were recorded every 5 minutes or hourly . 

Gosier Island 

Gosier Island is situated in the southern part of the Chandelew Island chain, north of the 

Mississippi River Delta. These islands are within the Breton National Wildlife Area, which has been 

designated as an EPA Class I area. The measurement station was established on the beach at 

approximately 29°33.69'N 890 03 .39'W. Major equipment deployed included a ThermoEnvironmental (TECO) Model 43A SO2 Analyzer, Weathertronics Micro-Response Anemometer and 

Wind Vane (later changed to a single Weathertronics Stratavane Windbird), and a Campbell Scientific 

CR10 datalogger. The SOZ Analyzer and CR10 housing were placed inside of a ventilated shelter on 

a scaffold about 2 m above ground level. An air temperature sensor and the wind instruments were 

tower mounted next to the scaffold with observation heights of 3 m and 6 m, respectively . In 

addition, a pond located adjacent to the beach site was instrumented with an Model PHTX-20 pH 

transmitter and Model CDTX-20 conductivity transmitter, both manufactured by Omega Engineering, 

Inc., and a water temperature sensor . Due to the lack of any commercial power source, all equipment 

was run off of a bank of 12V car batteries. This fact, combined with the remote locale and harsh 

environmental conditions, produced a non-continuous data record and made servicing the station 

difficult and, on occasion, hazardous to equipment and personnel . 

Meteorological parameters (wind speed and direction and air temperature) were recorded 

every five minutes while limnological values (pH, conductivity, temperature) were obtained hourly, 

whereas ambient SOZ concentrations were measured on a 45-60 minute basis. This was accomplished 

7 
by programming the CR10 to activate the SOZ Analyzer, allow it five minutes to stabilize (at which 

point a measurement was taken), and then de-activate. The measurement interval was calculated to 

provide the most observations possible given the expected power drain on the batteries between 

servicings . 

Power restraints also ruled out the use of an automated gas calibrator for the S02 Analyzer. 

Therefore, a calibration system consisting of flowmeters, a gas proportioner, and cylinders of zero 

air and span gas was assembled. Flows necessary to produce a five-point calibration of the Analyzer 

were derived. 

Ogawa Passive SOZ and Palmes Passive NO,, sensors were exposed throughout the field 

deployment at Gosier Island . Although correctly handled in the field, the long exposure times and 

improper storage of the sample tubes casts doubts on the validity of this data. 

Given the rugged conditions and the non-conventional method of operation, it is surprising 

that the only missing data in the air quality (S02) record occurred during 7 - 13 July. When the 

station was serviced on 7 July, it was found that the UV lamp in the Analyzer had failed, and the unit 

was subsequently taken o$line . The lamp and socket were replaced on the next trip out (13 July) and 

the Analyzer returned to service. 

On the other hand, wildlife inhabiting the island caused several problems. Pelicans and other 

marine waterfowl destroyed the Micro-Response Anemometer, resulting in a data gap in the wind 

speed record from 5 through 13 July. The wind vane was also damaged but apparently could still 

rotate for wind direction. The most serious damage was done to the cables connecting the pond 

instruments to the datalogger system, which were run on the surface over the dunes. Over time, 

animals apparently chewed into the cables, causing system shorts and the eventual failure of reliable 

data from the pond instruments on 21 July. These intermittent shorts were not detected in the field 

until 24 August, at which point the cables were disconnected from the datalogger . Large negative 

values in the S02 record from 13 to 24 August are probably due to these shorts . 

The station deployment and servicing schedule is listed below as taken from field log excerpts : 

29 June - all equipment deployed 

1 July - start of monitoring 

7 July - download, damage to wind instruments, S02 Analyzer taken offline due to lamp failure 

13 July - download, Stratavane Windbird installed, S02 Analyzer online 

21 July - download, S02 Analyzer calibration, failure of pond instruments 

5 August - download, S02 Analyzer calibration 

8 
17 August - download 

24 August - download, S02 Analyzer calibration, pond instruments disconnected 

31 August - download, S02 Analyzer calibration 

8 September - download, S02 Analyzer calibration 

26 September - station had exhausted power supply previous to this date. All equipment removed. 

Post calibration of S02 Analyzer performed at CSI lab . 

Breton Island (Chandeleur Islander) 

Breton Island is also in the EPA Class I area of the Chandeleur Islands, less than 10 miles 

southwest of Gosier Island . The reason for having this second site in such close proximity to the 

Gosier station was that AC power was available here. Although this area is more developed and 

utilized than pristine Gorier Island (considerable boat traffic, moored houseboats and camps, and the 

Kerr-McGee facility), continuous air quality measurements could be made which would back up those 

acquired at nearby Gosier . 

As in 1993, the houseboat Chandeleur Islander served as host to our station. The Islander 

was semi-permanently moored in Breton Sound at approximately 29°29.34N 89°10.45'W. Air quality 

equipment for this station consisted of a TECO Model 43A S02 Analyzer (rotated with a Model 43), 

a Monitor Labs, Inc. Model 8840 NO. Analyzer, and a TECO Model 146 Gas Calibrator (later 

changed to an Environics Series 100 Calibrator) with associated zero and span gas supplies. These 

units, along with the CR10 datalogger, were installed in a loft inside of the houseboat's loading bay. 

Unfortunately, this left them exposed to the marine environment and high temperatures (which may 

have contributed to problems later encountered with the units) . Passive air quality sensors (Ogawa 

and Palmes) were also deployed here as at Gorier. Meteorological parameters monitored were air 

temperature, relative humidity, atmospheric pressure, and wind speed and direction. 

Ambient concentrations of SO2, NO, NOZ, and NO, were recorded every five minutes along 

with wind speed and direction; air temperature, humidity and pressure were recorded hourly . Since 

the Chandeleur Islander was moored at a single point, it would turn on this axis in response to the 

wind and wave conditions . This necessitated the addition of a compass heading in order to determine 

the true wind direction. After field measurements were completed, it was discovered that the 

compass had not been functional during the entire period . Therefore, the wind record for this station 

has not been included in this analysis. 

This station experienced several other equipment problems which resulted in the loss of data. 

The TECO 146 Gas Calibrator failed on installation and was returned for repairs. On 13 July, the 

TECO 43A could not be calibrated and was taken offline. This created a gap in the S02 record until 

9 
27 July, when the unit was replaced with an older Model 43 . While functional, this Analyzer required 

considerable time to stabilize and so only minimal calibrations (0 - span) were done. The Calibrator 

was pulled again on 27 July due to incorrect gas flows. An Environics Gas Calibrator was installed 

on 5 August, but this unit required a larger pump to generate the flow volumes needed for calibrating 

the NO,, Analyzer. A large-capacity pump was supplied on 16 August, and the Model 43 Analyzer 

was replaced with a Model 43A. The 43A also displayed slow response time as well as considerable 

drift during calibration. To correct this, the optical bench in the unit was replaced on 23 August and 

good calibrations resulted . The second data gap occurred during the period of 27 - 30 August due 

to Islander personnel cutting power to the air quality monitors. Finally, the Model 43A Analyzer 

appeared to fail again on 2 September, ending the SOZ record for Breton. Servicing dates and notes are summarized below: 

30 June - station established, failure of Gas Calibrator 

1 July - observations start 

7 July - download, TECO 146 installed, air quality analyzers calibrated 

13 July - download, NOX Analyzer adjusted and re-calibrated, S02 Analyzer taken offline 

27 July - download, Model 43 (SOZ) installed and calibrated, TECO 146 pulled 

5 August - download, partial calibration after installation of Environics Calibrator 

16 August - download, new zero air pump installed, Model 43 replaced with Model 43A, calibration 

23 August - download, Model 43A repair, calibration 

30 August - download, calibration 

7 September - download, Model 43A pulled, calibration of NO,, Analyzer 

12 September - download, calibration of NO. Analyzer 

26 September - download, calibration of NO. Analyzer, end of station record 

Pass-A-Loutre 

The headquarters building of the Louisiana Wildlife and Fisheries in the Pass-A-Loutre (PAL) 

Game and Fish Reserve was the site of the third monitoring station. The building is located on Dennis 

Pass in the Mississippi River Delta, an EPA designated Class II area. This was the most favorable 

site in that it offered ease of access (by boat or seaplane) regardless of weather, continuous AC power 

10 
for the Analyzers, and a climate-controlled room for the equipment. The effect of these factors is 

evident in the higher percentage of data obtained here . 

Station setup was similar to that at Breton Island . TECO Models 43A (S02), 42 (NOX), and 

146 (Calibrator) were installed for air quality monitoring. A 10 m tower was erected for wind speed 

and direction (via Weathertronics Micro-Response Anemometer and Vane). Other recorded 

parameters were air temperature, relative humidity, and atmospheric pressure . Sample interval for 

the air quality parameters as well as wind speed and direction was five minute ; remaining 

meteorological parameters were recorded hourly . No passive sensors were deployed . 

The only significant data loss resulted from the failure of the NO. Analyzer as the station was 

being established. The NO. Analyzer was repaired and installed on 7 July. The unit remained in 

service throughout the rest of the deployment, although problems with the keyboard and display 

prompted the replacement of the processor board on 16 August. On 7 September, the NO. Analyzer 

could not be calibrated . The field technician dis-assembled the unit on site and cleaned the lens and 

then partially removed the pump. A foreign substance was found inside the pump which was 

obstructing the flapper valves . Once removed, the unit operated normally and good calibrations 

followed . Following are field servicing notes for the PAL stationI July - station established and measurements begin, NO,, Analyzer failure 

7 July - NOR Analyzer installed 

14 July - download, air quality Analyzers adjusted and calibrated but suspect error in Calibrator 

22 July - download, Calibrator checked with Gilibrator bubble meter and adjusted, good calibrations 

of Analyzers 

26 July - download, calibration 

4 August - download, anemometer changed, calibration 

11 August - download, calibration 

16 August - download, processor board in NO. Analyzer changed, calibration 

23 August - download, calibration 

30 August - download, calibration 

7 September - download, repair of pump in NO. Analyzer, calibration 

12 September - download, calibration, end of station record 

11 
3. Calibrations 

As indicated in the servicing records for each station, considerable effort was devoted to 

keeping the air quality monitors calibrated and in good operating condition. Typically when the 

stations were serviced, the monitors were either within acceptable error or not working at all. 

Calibrations were performed by exposing the analyzers to known concentrations of the desired 

pollutants (SO2, NO) at several points from 0 ppb to nearly 500 ppb (full scale) . Test concentrations 

were obtained from compressed gas cylinders (traceable EPA Protocol gases) containing a mix of 

approximately 50 ppm SOZ and 50 ppm NO with a nitrogen balance. This gas was then diluted 

through a zero-air system with scrubbers to produce concentrations at several points . As described 

in the Code of Federal Regulations (40 CFR 58, App. B, 1994), one precision point and two or more 

additional points evenly spaced up to the full scale were checked to establish the relationship between 

the analyzer response and the pollutant concentration. If properly calibrated and operating nominally, 

the analyzers used in this study should exhibit a linear response as shown in Fig. 2; therefore accuracy 

of measurements should be consistent from low to high concentrations . At Gosier Island, calibration 

of the SOZ analyzer was performed manually by mixing test gas with that from a cylinder of zero air 

through a gas proportioner (all flowmeters were certified at the Louisiana Department of 

Environmental Quality) . Automated gas calibrators were required at Breton Island and Pass-ALoutre to produce the gas phase titration needed for calibration of the NO,, analyzers . In this 

technique, ozone (03) is added to the calibrated NO channel in the reaction 

N0 + 03 , N02+02 

The decrease in the NO concentration from this reaction is equivalent to the N02 produced. Thus 

N02 concentration is derived from the difference between calibrated NO. and NO channels. 

Gosier Island 

Table lA lists the precision data for the TECO Model 43A SO2 Analyzer deployed at Gosier 

Island . The data are reported as a 95 percent confidence interval bounded by two percentile values 

as described in 49 CFR 58, App. B (1994) . The interpretation is that for any randomly selected value 

within the database represented, there is only 5 percent probability that its accuracy is outside of the 

boundaries defined as the upper and lower 95-percent confidence limits . All air quality measurements 

are in ppb. 

Table 1B presents accuracy data at other selected calibration points . It should be noted that 

the Tables reflect values obtained immediately before the Analyzer was adjusted (greatest error) . 

Also, a final calibration of the Analyzer on-site was not possible due to the lack of power. The unit 

was shipped back to the Coastal Studies Institute and calibrated under laboratory conditions . 

12 
U 

N 

U 

Pass-A-Loutre 

1 July 1994 

y=1 .Ox-1 .05 

Corr = 0.99 

to 

O 

) 

0 100 200 300 400 

S02 Expected ppb 

500 

500 

400 

300 

U 

Q 

C) 200 

z 

100 

0 

Pass-A-Loutre 

1 July 1994 

""""""y = 1 .Olx - 2.46 (for NO and NOx) 

Corr = 0.99 

- y = 0.99x = 0.39 (for NO 2) 

Corr = 0.99 

NO 

NOx 

N02 

0 100 200 300 400 

NOD Expected ppb 

Figure 2 . Calibration curves from Pass-A-Loutre air quality analyzers. 

500 

13 
Whenever an analyzer is physically moved to a new location, has undergone repairs, has been 

inoperative for an emended period, or has obviously malfunctioned, a new multi-point calibration 

must be conducted (EPA, 1979). Obviously, this calibration may not be representative of the 

response of the analyzer in its former state. In this case, if this post-calibration is excluded, the mean 

precision error would be -0.13 with a standard deviation of 13.12 . Accuracy values would likewise 

improve. Since deleting the final calibration would also invalidate all air quality data collected 

between that point and the last acceptable calibration, it has been included in the tables . 

Breton Island 

Calibration values at this station were made more complicated due to the previously described 

problems with the calibration system and exchange of the SOZ Analyzer on two occasions . Precision 

and accuracy data for the SOZ Analyzer are listed in Tables 2A and 2B while values for the NO,, 

Analyzer are in Tables 3A and 3B. The wide range of expected values for N02 in Tables 3A and 3B 

are the result of different flow rates (and thereby concentrations) associated with the gas calibration 

systems and zero air supplies used at this station. 

Pass-A-Loutre 

Precision and accuracy data for the SOZ Analyzer at the PAL station are listed in Tables 4A 

and 4B and for the NO,, Analyzer in Tables SA and SB, respectively . The calibration performed at 

this station on 14 July is not included due to incorrect flows in the TECO 146 Gas Calibrator ; 

however, values obtained after the Calibrator was corrected on 22 July (before the Analyzers were 

adjusted) are incorporated. If only values measured after the re-calibration are considered, the mean 

precision error for SOZ reduces to 2.4 with a standard deviation of 2.6 . On 7 September, a partial 

calibration was performed on the defective NO,, Analyzer before the unit was taken online and 

repaired . These values are listed in Tables SA and SB but could have been deleted as described under 

Gosier Island above. Again, if excluded the average precision error and accuracy for the NO,, 

Analyzer would improve significantly . 

4. Data Return 

Due in part to the relatively short duration of the field measurement period, virtually all 

available data from each station is employed for this report . It has been shown that each air quality 

monitor was subjected to frequent multi-point calibrations with resulting mean precision errors of less 

than 10%. The minimum requirements for PSD monitoring are determined by many factors including 

field conditions, the objectives of monitoring, level of quality data needed, expertise of personnel, cost 

of control procedures, and pollutant concentration levels (40 CFR 58, App. B, 1994). The goal is 

to provide data of adequate quality to meet the monitoring objectives, and to minimize the loss of air 

quality data due to malfunctions and out-of-control conditions . Taking into account the operating 

environments and logistic difficulties, it was not intended that these stations would conform to EPA 

recommendations for Class I and II PSD Air Monitoring (i .e ., regulatory purposes); rather, they were 

14 
Table IA. 

Gosier Island SOz Precision Data 

Analyzer: TECO 43A 

Date Expected ppb Precision Actual ppb % Error 

7/21/94 129 92 -28 .68 

7/21/94 (Re-cal) 129 135 4 .65 

8/5/94 129 142 10.08 

8/24/94 129 137 6.20 

8/31/94 129 138 6.98 

9/8/94 129 129 0 

Post-Cal 129 174 34.88 

Sum of D(I) 34.11 

Mean of D(I) 4 .87 

Standard Deviation 17 .25 

Upper 95% Probability 38 .68 

Lower 95% Probability -28.94 

15 
Table 1B . 

Gosier Island SOZ Accuracy Data 

Analyzer: TECO 43A 

Date Expected ppb Actual ppb % Error 

7/21/94 464 309 -33 .41 

7/21/94 (Re-cal) 464 464 0 

8/5/94 464 463 -0.22 

8/24/94 464 468 0 .86 

8/31/94 464 456 -1 .72 

9/8/94 464 616 32.76 

9/8/94 (Re-cal) 464 466 0.43 

Post-Cal 464 600 29.31 

Mean 3 .5 

Standard Deviation 19.22 

7/21/94 229 154 -32.75 

8/5/94 229 258 12.66 

9/8/94 229 232 1 .31 

Post-Cal 229 305 33 .19 

Mean 3 .6 

Standard Deviation 23 .9 

16 
Table 2A. 

Breton Island SOZ Precision Data 

Analyzer: TECO 43 and 43A 

Date Expected ppb Precision Actual ppb % Error 

7/7/94 92 92 0 

8/6/94 90 88 -2.22 

8/23/94 90 110 22.22 

8/30/94 90 105 16.67 

Sum of D(I) 36.67 

Mean of D(I) 9.17 

Standard Deviation 10 .49 

Upper 95% Probability 29 .73 

Lower 95% Probability -11 .39 

Table 2B . 

Breton Island SOz Accuracy Data 

Analyzer: TECO 43 and 43A 

Date Expected ppb Actual ppb % Error 

7/7/94 449 461 2.67 

7/27/94' 449 443 -1 .34 

8/5/94` 449 360 -19 .82 

8/5/94 (Re-cal)" 449 447 -0 .45 

8/16/94 450 428 -4.89 

8/23/94 450 448 -0.44 

8/30/94 450 451 0.22 

Mean -3 .44 

Standard Deviation 7.01 

'Model 43 

17 
Table 3A. 

Breton Island NO., Precision Data 

Analyzer : Monitor Labs 8840 

Date 

Expected 

ppb 

Actual NO 

ppb 

Actual NOX 

ppb % Error NO % Error NO, 

7/7/94 91 96 97 5 .50 6.59 

7/13/94 91 91 88 0 -3 .30 

7/27/94 91 93 89 2.20 -2.20 

8/5/94 91 81 80 -10.99 -12 .09 

8/5/94 (Re-cal) 91 72 72 -20.88 -20 .88 

8/16/94 91 90 88 -1 .10 -3 .30 

8/23/94 90 89 89 -1 .11 -1 .11 

8/30/94 90 86 85 -4.44 -5 .56 

9/7/94 90 88 89 -2.22 -1 .11 

9/12/94 90 92 91 2 .22 1 .11 

9/26/94 90 88 86 -2 .22 -4.44 

Sum D(I) -33 .04 -46.29 

Mean D(I) -3 -4 .21 

Standard Deviation 6.94 6 .82 

Upper 95% Probability 10.6 9 .16 

Lower 95% Probability -16.60 -17 .58 

18 
Table 3A Continued 

Date Expected ppb Actual NOZ ppb % Error 

7/7/94 79 80 1 .27 

7/13/94 82 83 1 .22 

7/27/94 64 65 1 .56 

8/16/94 119 127 6.72 

8/23/94 103 128 24.27 

8/30/94 119 139 16.81 

9/7/94 126 139 10.32 

9/12/94 126 126 0 

9/26/94 113 137 21 .24 

Sum D(I) 83 .41 

Mean D(I) 9.27 

Standard Deviation 8.86 

Upper 95% Probability 26.64 

Lower 95% Probability -8.10 

19 
Table 3B. 

Breton Island NO. Accuracy Data 

Analyzer : Monitor Labs 8840 

Date 

Expected 

ppb 

Actual NO 

ppb 

Actual NOX 

ppb % Error NO % Error NO,, 

7/7/94 465 475 478 2.15 2.80 

7/13/94 465 463 464 -0.43 -0.22 

7/27/94 465 465 465 0 0 

8/5/94 465 401 411 -13 .76 -11 .61 

8/5/94 (Re-cal) 465 462 464 -0.65 -0.22 

8/16/94 450 451 454 0.22 0.89 

8/23/94 450 449 451 -0 .22 0.22 

8/30/94 450 459 463 2 .00 2 .89 

9/7/94 450 458 459 1 .78 2 .00 

9/12/94 450 455 454 1 .11 0.89 

9/26/94 450 440 441 -2.22 -2.00 

Mean D(I) -0.91 -0.4 

Standard Deviation 4.25 3 .80 

20 
Table 3B Continued 

Date Expected ppb Actual NOZ ppb % Error N02 

7/7/94 265 268 1 .13 

7/13/94 387 385 -0.52 

7/13/94 (Re-cal) 350 353 0.86 

8/16/94 328 350 6.71 

8/23/94 340 363 6.77 

8/30/94 340 362 6.47 

9/7/94 357 374 4.76 

9/12/94 372 378 1 .61 

9/26/94 346 364 5.20 

Mean D(I) 3 .67 

Standard Deviation 2 .72 

21 
Table 4A. 

Pass-A-Loutre SOZ Precision Data 

Analyzer: TECO 43A 

Date Expected ppb Precision Actual ppb % Error 

7/l/94 91 91 0 

7/22/94 85 47 -44.71 

7/22/94 (Re-cal) 85 86 1 .18 

7/26/94 85 83 -2 .35 

8/4/94 85 84 -1 .18 

8/11/94 85 87 2.35 

8/16/94 85 87 2.35 

8/23/94 85 88 3 .53 

8/30/94 85 89 4.71 

9/7/94 85 89 4.71 

9/12/94 85 90 5 .88 

Sum D(I) -23 .53 

Mean D(I) -2.14 

Standard Deviation 13 .68 

Upper 95% Probability 24.67 

Lower 95% Probability -28 .95 

22 
Table 4B. 

Pass-A-Loutre SOZ Accuracy Data. 

Analyzer: TECO 43A 

Date Expected ppb Actual ppb % Error 

7/1/94 452 455 0 .66 

7/22/94 427 244 -42 .86 

7/22/94 (Re-cal) 427 428 0 .23 

7/26/94 427 422 -1 .17 

8/4/94 427 426 -0.23 

8/11/94 427 435 1 .87 

8/16/94 427 435 1 .87 

8/23/94 427 434 1 .64 

8/30/94 427 439 2.81 

9/7/94 427 440 3 .04 

9/12/94 427 450 5.39 

Mean D(I) -2.43 

Standard Deviation ~ 12.90 

23 
Table SA. 

Pass-A-Loutre NOX Precison Data 

Analyzer : TECO 42 

Date 

Expected 

ppb 

Actual NO 

ppb 

Actual NO,, 

ppb % Error NO % Error NO,, 

7/22/94 85 70 69 -17.65 -18.82 

7/22/94 (Re-cal) 94 96 97 2.13 3 .19 

7/26/94 85 87 87 2.35 2.35 

8/4/94 94 90 90 -4.26 -4.26 

8/11/94 94 80 79 -14.89 -15 .96 

8/11/94 (Re-cal) 94 90 91 -4.26 -3 .19 

8/16/94 94 95 95 1 .06 1 .06 

8/23/94 94 84 84 -10.64 -10.64 

8/23/94 (Re-cal) 94 95 95 1 .06 1 .06 

8/30/94 94 92 92 -2.13 -2.13 

9/7/94 94 46 46 -51 .06 -51 .06 

9/7/94 (Re-cal) 94 97 97 3 .19 3 .19 

9/12/94 94 89 89 -5 .32 -5 .32 

Sum D(I) -100.42 -100.53 

Mean D(I) -7.73 -7.73 

Standard Deviation 14.06 14.25 

Upper 95% Probability 19.83 20.20 

Lower 95% Probability -35 .29 -35 .66 

24 
Table SA Continued 

Date Expected ppb Actual NOZ ppb % Error N02 

7/22/94 73 63 -13 .70 

7/22/94 (Re-cal) 89 94 5.62 

7/26/94 90 87 -3 .33 

8/4/94 97 92 -5 .16 

8/11/94 99 98 -1 .01 

8/16/94 97 96 -1 .03 

8/23/94 98 98 0 

8/30/94 92 92 0 

9/12/94 92 93 1 .09 

Sum D(I) -17.52 

Mean D(I) -1 .95 

Standard Deviation 5 .01 

Upper 95% Probability 7.87 

Lower 95% Probability ~ -11 .77 

25 
Table SB . 

Pass-A-Loutre NO,, Accuracy Data 

Analyzer: TECO 42 

Date 

Expected 

ppb 

Actual NO 

ppb 

Actual NOX 

ppb % Error NO % Error NOX 

7/22/94 454 336 329 -25 .99 -27 .53 

7/22/94 (Re-cal) 454 452 451 -0.44 -0 .66 

7/26/94 454 420 421 -7.49 -7.27 

8/4/94 454 433 431 -4.63 -5 .07 

8/11/94 454 407 404 -10.35 -11 .01 

8/11/94 (Re-cal) 454 446 448 -1 .76 -1 .32 

8/16/94 454 451 452 -0 .66 -0.44 

8/23/94 454 398 398 -12 .34 -12.34 

8/23/94 (Re-cal) 454 453 455 -0.22 0.22 

8/30/94 454 427 429 -5.95 -5 .51 

9/7/94 454 293 293 -35 .46 -35 .46 

9/7/94 (Re-cal) 454 453 453 -0.22 -0 .22 

9/12/94 454 i 422 T 424 -7.05 -6.61 

Mean D(I) -8 .66 -8 .71 

Standard Deviation 10 .32 10 .59 

26 
Table SB Continued 

Date Expected ppb Actual NO, ppb % Error NO, 

7/22/94 262 249 -4.96 

7/22/94 (Re-cal) 346 346 0 

7/26/94 324 319 -1 .54 

8/4/94 340 330 -2 .94 

8/11/94 350 346 -1 .14 

8/16/94 352 346 -1 .71 

8/23/94 310 287 -7.42 

8/23/94 (Re-cal) 352 349 -0.85 

8/30/94 335 333 -0.6 

9/7/94 357 354 -0.84 

9/12/94 331 329 -0.6 

Mean D(I) -2.06 

Standard Deviation 2 .15 

27 
designed for scientific purposes (to obtain a quantitative first-look at the pollutant levels existing over 

these areas and the meteorological conditions which could affect those levels) . With this in mind, and 

considering that the monitors were generally well calibrated, the air quality data is presented as 

recorded with the only adjustment being the removal of zero offsets. 

Hourly values of wind speed and direction were derived through a vector average for all hours 

reporting six or more 5-minute measurements. Other meteorological parameters not reported hourly 

and all air quality data were reduced by arithmetic average. Average concentrations less than zero 

were considered non-detect and reported as zero assuming the analyzer was operating nominally. 

In other words, if negative values were recorded during a period between two acceptable calibrations, 

those measurements were considered valid and retained as 0 ppb. Over time, cumulative zero drifts 

of 20 to 30 ppb and span drifts of 20 - 25% of full scale may be observed before the analyzer should 

be adjusted and re-calibrated (EPA, 1979). 

Table 6 lists the percentage of hourly data return for measured parameters at each station 

(note that NOZ implies NO and NO,,). Values represent percentage of possible record, not month. 

Computed hourly values are presented graphically for Gosier Island in Figs. 3a - 3m, for Breton 

Island in Figs. 4a - 4u, and for Pass-A-Loutre in Figs. Sa - Saa. Numerical values are listed in 

Appendices A - C. Interpretation of the data is provided in the Results and Discussion Section. 

It can be seen in the figures that parts of the air quality records have been designated as 

"Questionable", due primarily to lack of successful monitor calibration or related equipment failures 

as described previously . In the Gosier SOZ record, July 1 - 7 is suspect since no span calibration was 

performed on installation and the Analyzer subsequently failed (Fig. 3a). Large negative values were 

recorded during 12 - 24 August (Fig. 3b), however good calibrations were obtained on 5 and 24 

August. It should be noted that, at an undetermined point before the end of the Gosier SOZ record, 

battery power levels had become insufficient to run to air quality monitor (Fig. 3c). 

Both SOz and NO. data have been removed from the Breton Island air quality record during 

the period of 7 - 14 July due to an unexplained lack of response from the monitors (Figs. 4a, d, g, and 

j) . In Figure 4c, failure of the SOZ Analyzer caused hourly measurements to go negative after 2 

September. 

Calibration of the air quality monitors at Pass-A-Loutre was performed on 14 July even 

though it was suspected that the Gas Calibrator was out of specifications. This was confirmed on 22 

July, at which point the Calibrator was corrected and the air quality monitors brought back into line 

(see Calibrations) . In addition, no span calibration was conducted on the NO,, Analyzer when 

installed on 7 July. Figures Sa, d, g, and j illustrate these events . As shown in Figs. Sf, i, and 1, the 

pump in the NO. Analyzer began failing before being repaired on 7 September; however NO. data 

appears consistent throughout the period of 30 August to 7 September. 

28 
Table 6. 

Percentage Data Return 

Month 

Air 

Temp . Press. 

Relative 

Humidity 

Wind 

Speed 

Wind 

Direct. SOZ NOZ 

Gosier Island 

July 99.9 NM NM 73 .8 99.6 79.4 NM 

Aug 99.3 NM NM 99.3 99 .3 98.4 NM 

Sept 100 NM NM 100 100 99.7 NM 

Breton Island 

July 97.3 97.3 97 .3 NM NM 34.3 77 .6 

Aug 96.4 96 .4 96.4 NM NM 85 .6 85.6 

Sept 99 99 99 NM NM 6 .6 98.7 

Pass-A-Loutre 

July 97.5 97.5 97.5 97.9 97 .9 97.9 78 .7 

Aug 97.6 97.6 97.6 98 .3 98 .3 98 98 

Sept 97.5 97.5 97.5 97 .9 97.9 97.9 97 .9 

NM - Not Measured 

29 
5. Radiosondes 

The final component of the field measurement program consisted of atmospheric profiles 

obtained at each station throughout the deployment period . Table 7 denotes the date, time, and 

location of each launch . The majority of launches were scheduled to coincide with 00 and 12 GMT 

(standard National Weather Service launch times) . Those remaining were launched in the local 

afternoon hours to investigate the variation of the mixing heights. 

Sensor packages used were A.I .R., Inc. Model AS-3A-403 Airsondes carved aloft on 200 gm 

balloons . The Airsonde measures air temperature via bead thermistor, relative humidity by carbon 

hygristor, and barometric pressure with an electronic aneroid capacitance pressure sensor mounted 

internally on the circuit board. Data is sampled and transmitted every 5 - 6 seconds. An A.I .R., Inc. 

Atmospheric Data Acquisition System (ADAS) was employed to receive and interpret the transmitted 

signal . 

Prior to launch, surface temperatures (dry- and wet-bulb) were measured with an electric 

psychrometer, and station pressure with both an aneroid and digital barometer. Other conditions 

(wind speed and direction, cloud cover, etc.) were estimated by the observer . 

Table 7. 

Radiosonde Launch Information 

Profile Location Date/Time Local Date/Time GMT 

STA1RS01 Gosier Island 8/24/94 1216CDT 8/24/94 1716GMT 

STA2RS01 Breton Island 8/5/94 1558CDT 8/5/94 2058GMT 

STA2RS02 Breton Island 8/16/94 1900CDT 8/17/94 OOOOGMT 

STA2RS03 Breton Island 8/17/94 0631CDT 8/17/94 1131GMT 

STA2RS04 Breton Island 8/23/94 1902CDT 8/24/94 0002GMT 

STA2RS05 Breton Island 8/24/94 0706CDT 8/24/94 1206GMT 

STA2RS06 Breton Island 8/30/94 1905CDT 8/31/94 OOOSGMT 

STA2RS07 Breton Island 8/31/94 0703CDT 8/31/94 1203GMT 

STA2RS08 Breton Island 9/7/94 1930CDT 9/8/94 0030GMT 

STA2RS09 Breton Island 9/8/94 0701 CDT 9/8/94 1201 GMT 

STA3RS01 PAL 8/4/94 1900CDT 8/5/94 OOOOGMT 

STA3RS02 PAL 9/7/941304CDT 9/7/941804GMT 

30 
w 

2 

20 

a 

a 

N 

15 

Z 

0 x 

C 10 

C7 

5 

0 

Questionable ~ Monitor 

Data ; Failure 

----------------~r -------------------- 

1 

1 

1 

1 

1 

Service Calibration 

I 

I 

I 

1 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure 3a. July 1994 hourly SOZ concentrations at Gosier Island . 
1.2 

1 .0 

.0 0.8 

a 

a 

N 

Z 

~0 0.6 

w 

N 

L 91 

0.4 

0.2 

0.0 

Calibration ~ Service 

Calibration 

i 

------------------- 

1 1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 1 

1 I 1 

1 1 

1 1 

1 

1 

1 

1 

1 

1 

1 

1 

Questionable ~ Questionable 

i 

1 1 I 

Data ~ Data ~ i 

4-----------E~ - ------------------- ~ 1 

1 1 

1 

1 

1 

1 1 1 

1 

1 

1 

1 1 1 

i 

i 

13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure 3b . August 1994 hourly SOZ concentrations at Gosier Island . 
1 .2 

1 .0 

,0 0.8 

4 

a 

N 

L 

0 . 6 

C 

0 . 4 

0.2 

0.0 

~ Calibration ; End i 

Deployment 

i 

i i 

i 

1 

1 

1 

1 

1 

1 

1 

1 

i 

1 

1 

1 

1 

1 

I 

1 

1 

i i 

i 

i 

i 

5 9 13 17 21 25 29 

September 1994 

Figure 3c . September 1994 hourly SOZ concentrations at Gosier Island . 
20 

15 

b 

¢, 10 

.y 

5 

Anemometer Damaged 

v. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v 

0 

20 

w 

1$ 

a 10 

0 0 

N -r 5 

0 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure 3d . July 1994 hourly wind speeds at Gosier Island and NOAA buoy 42007 . 
16 

w 

12 

E 

g 

c~. 

.N 

4 

0 

16 

a. 

0 

0 

N `r 4 

12 

0 F i 

T~TS 

i 

FTtl r F~ 1 SI1 -i-1 -F1 1 i'~ i 1 F-1 I +- 1F-T-1 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure 3e. August 1994 hourly wind speeds at Gosier Island and NOAH buoy 42007. 
16 

12 

a. 

. N 

0 

t7 4 

0 

16 

w 

12 

V1 

G 

N 

a. 

0 0 

N ,,1' 4 

End 

Deployment 

0 ' 

1 5 9 13 17 21 25 

September 1994 

Figure 3f. September 1994 hourly wind speeds at Gosier Island and NOAA buoy 4200'7 . 

29 
W 

J 

360 

315 

270 

c 

-o 

225 

A 180 

' a 135 

90 

45 

0 

360 

315 

270 

c 0 

'~ 225 

A 180 

135 

90 

45 

0 

Figure 3g. July 1994 hourly wind directions from Gosier Island and NOAH buoy 42007 . 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 
w 

00 

360 

315 

270 

0 

225 

180 

0 135 

C7 

90 

45 

0 

360 

315 

270 

0 

225 

a 

~1 180 

c135 

90 

45 

0 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure 3h. Aujust 1994 hourly wind directions from Gosier Island and NOAA buoy 42007. 
360 

315 

270 

o 

225 a 

180 

L.. 

0 135 

90 

45 

0 

360 

w 110 315 

270 

c 0 

225 

a 

(.~ 180 

a 135 

v 

90 

45 

0 

End 

Deployment 

1 5 9 13 17 21 25 29 

September 1994 

Figure 3i . September 1994 hourly wind direction at Gosier Island and NOAH buoy 42007 . 
32 

30 

U 

O , 28 

E-' 

a~ 

'a 26 

c7 

24 

22 

32 

.A 0 

30 

U 

° ,, 28 

H 

° 026 

N 

24 

22 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure 3j . July 1994 hourly air temperatures at Gosier Island and NOAH buoy 42007 : 
32 

30 

a 28 

w 

E- " 

~. 

~ 26 0 

C7 

24 

22 

32 

30 

U ° . Zs 

E-' 

o 

`6 

N 

24 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure 3k. August 199 hourly air temperatures at Gosier Island and NOAH buoy 42007. 
31 

29 

U 27 

0 

V 

H 25 

V 

.N 

0 23 

21 

19 

31 

.A 

N 

29 

U 27 

0 

V 

F" 25 

0 0 

v 23 

21 

19 

End 

Deployment 

1 5 9 13 17 21 25 

September 1994 

Figure 31 . September 1994 hourly air temperatures at Gosie: Island and NOAA buoy 42007. 

29 
w 

38 

v 36 

° 34 

c. 

E 32 

F' 30 

-o 

0 28 

a' 26 

24 

9.0 

8.5 

x 

a. 

8.0 

7.5 

14 

12 

10 

~ 8 

~ 6 

`n 4 

0 

End Data Record 

End Data Record 

End Data Record 

Invalid Data 

4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..~ 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 

July 1994 

31 

Figure 3m. July 1994 hourly pond data Gosier Island (see text for explanation) . 
13 

12 

11 

10 

a 9 

N 

0 

as g 

d' 7 

a. 

6 

C 

R 5 

C 

O 

4 

i i 

i Calibration 

i 

i 

i 

i 

i i 

i 

i 

i 

1 

Questionable 

i Data 

-----' 

i 

i 

i 

i 

i i 

i 

1 

-----Dj 

Calibration 

1 i 

Monitor Failure 11 

C-------------------------------------{~i 

1 

1 

1 

1 

1 

Calibration 

11 13 15 17 19 21 23 

July 1994 

25 27 29 31 

Figure 4a. July 1994 hourly SOZ concentrations at Breton Island . 
55 

SO 

45 

J2 40 

a 

~ 35 

ao 

30 

~+°,~ 25 

C 

R 

~ 20 

15 

10 

5 

i Calibration ~ Calibration ~ Calibration 

------------------- ==' i i i 

1 I 1 1 

I 1 j j 

Powcr 

Lost 

i i 

i 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure 4b . August 1994 hourly SOz concentrations at Breton Island . 1 

0 
1 .2 

1 .0 

a 

a 

e~ 0.8 

O 

el~ 

Q 

0.6 

0 

w 

c 

0.4 

0.2 

0.0 

i i 

Calibration 

i 

i 

i 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

i 

Questionable i 

302 Monitor Removed From Service 

Data i 

~------------di< ------------------------------------------ 

i 

i 

I 

I 

1 

1 

1 

1 

1 

1 

1 

i 

i i i 

i 

i 

i 

i i 

i i i i 

N;nd 

Deployment 

13 17 21 

September 1994 

25 29 

Figure 4c. September 1994 hourly SOZ concentrations at Breton Island . 
11 

180 

i 

Calibration ~ Calibration 

i 

i 

i i 

i 

Questionable 

Data 

160 

K~---------------f~ 

i 

140 

0. 

120 

z 

a Loo 

t 

A so 

C 

C 

60 

PQ 

Calibration 

40 

20 

0~ 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure 4d. July 1994 hourly NO concentrations at Breton Island . 
00 

240 

200 

a 

0 160 

z 

120 

x 

C 

r 

80 

40 

0 

Calibration Calibration Calibration 

------------------{=i 

i i 

i 

i 

i 

i 

i i 

1 1 

~---- 

Power 

i Lost i 

i 

i 

1 3 5 7 9 11 13 15 17 19 21 23 

August 1994 

25 27 29 31 

Figure 4e. August 1994 hourly NO concentrations at Breton Island . 
250 

200 

a 

a 

°z 

~ 150 

0 0 

x 

too 

c 0 

.+ 

PQ 

50 

i Calibration Calibration I End 

i Deployment 

i i i i i i 

i 

i 

i 

i 

i i 

i 

i 

i 

i i 

i i 

5 9 13 17 21 

September 1994 

25 29 

Figure 4f. September 1994 hourly NO concentrations at Breton Island . 
0 

60 

50 

a 

O40 

N 

-~, 30 

x 

C 

r 

0 20 

L 

10 

Calibration 

i 

--------------- 

i i i i 

Questionable 

i Data 

K-----------------C, 

I 

I 

1 

1 

1 

1 

1 

i 

i 

1 

1 

1 

I 

1 

1 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 

July 1994 

Figure 4g . July 1994 hourly NOZ concentrations at Breton Island . 

i 

i 

Calibration 

" --------------------L~ 

i 

i i 

i 

i 

i 

i 

I 

1 

1 

I 

1 

1 

29 31 
50 

40 

to. 

a 

N 

0 

z 

~ 30 

d 

Z 

`" x 

zo 

Q 0 

L 

10 

Figure 4h. August 1994 hourly NOz concentrations at Breton Island . 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 
N 

35 

30 

a 25 

a 

N 

d 

OA 

20 

D 

W 

p I S 

C 

O 

10 

Calibration ; CaUbration ~ End 

i Deployment 

i 

i i 

i 

i 

i i 

I 

I 

t 

1 

1 

1 

1 

1 

1 

1 

1 

1 1 

1 1 1 

I 1 

1 

1 

1 

1 

1 1 

1 

1 

1 

1 1 1 1 

1 

1 

1 

1 I 

1 

1 

I 

1 

1 

1 1 1 

1 1 

1 1 

1 

1 

1 

1 1 1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

t 

13 17 21 25 29 

September 1994 

Figure 4i . September 1994 hourly NOZ concentrations at Breton Island . 
W 

225 

200 

175 

.a 

a a 

O 150 

z 

its 

4 100 

.ry 

FH 

75 

V 

50 

25 

0 

i 

~ Calibration 

1 I 

i 

i 

Questionable i 

Data 

---------------- 1--4 

i 

1 1 

1 1 

1 1 

I 1 

Calibration Calibration 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure 4j . July 1994 hourly NO,, concentrations at Breton Island . 
.A 

275 

250 

225 

200 

a a 

N 

z ins 

ea 

a 150 

41 

x izs 

9 

C 

R 

100 

75 

50 

zs 

Calibration ~ Calibration ~ Calibration ' 

--=~---------------------------------i==~~ 

I 

I 

I I 

I 

i 

j I 

i 

s = 

I 

4.______-_____{?' i 

i 

i i Power 

I 

~ ! Lost ' i 

i 

i 's I 

16u W : 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure 4k . August 1994 hourly NO,, concentrations at Breton Island . 

0 
300 

250 

a a 

a 200 

z 

150 

0 x 

C 

R 

C 

100 

L 

50 

0 

i 

Calibration i Calibration ~ End 

i i Deployment 

i i 

i 

i i 

i 

1 1 

1 1 

1 

1 

1 

1 1 1 

1 1 

1 1 

1 1 1 

1 1 

1 

1 

1 

1 

1 

1 

1 

1 

1 1 

i 

i 

1 5 9 13 17 21 25 

September 1994 

Figure 41 . September 1994 hourly NO,, concentrations at Breton Island . 

29 
32 

30 

U 

28 

.5 

m 

E-' 

c 

2 6 

24 

22 

32 

30 

U 

° ,. 28 

E0 26 

N 

24 

22 ' 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure 4m. July 1994 hourly air temperatures from Breton Island and NOAA buoy 42007 . 
v 

32 

30 

U 28 

0 

26 

0 +. 

as 24 

22 

20 

32 

30 

U 28 0 

'" 26 

c 0 

24 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure 4n. August 1994 hourly air temperatures from Breton Island and NOAH buoy 42007. 

22 

20 
32 

30 

- 28 

U 0 

~ 26 

E-' 

24 

A 

22 

18 

32 

20 

00 

3 0 

28 

U 0 

~ 26 

H 

0 24 

N 

22 

ZO 

18 

1 5 9 13 17 21 25 29 

September 1994 

Figure 40 . September 1994 hourly air temperatures from Breton Island and NOAA buoy 42007. 
1026 

1024 

1022 

1020 

y 

H 

1018 

c 

1016 

1014 

1012 

1010 

1026 

1024 

1022 

1020 

V1 

y iols 

0 1016 0 

N 

1014 

1012 

1010 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure 4p. July 1994 hourly atmospheric pressure from Breton Island and NOA~1 buoy 42007. 
0 

1024 

1022 

1020 

1018 

N 

H 

1016 

a 

1014 

1012 

1010 

1008 

1024 

1022 

_0 1020 

1018 

. 1016 

a 

0 1014 0 C1a 

1012 

1010 

1008 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure 4q . Aajust 1994 hourly atmospheric pressure from Breton Island and NOAH buoy 42007. 
1024 

1022 

1020 

1018 

y 

1016 

a 

0 1014 

1012 

1010 

1008 

1024 

1022 

1020 

1018 

lA 

1016 

a 

0 1014 

C1a 

1012 

1010 

1008 

1 5 9 13 17 21 25 29 

September 1994 

Figure 4r. September 1994 hourly atmospheric pressure from Breton Island and ?VTOAA buoy 42007. 
100 

90 

80 

E 

x 

.~, 

N 

O 70 Y 

M Lr 

W 

60 

50 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure 4s. July 1994 hourly relative humidity from Breton Island . 
100 

90 

0 

80 

x 

W 

o 70 

M it

W 

VO 

SO 1 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

Au~ust 1994 

Figure 4t. August 1994 hourly relative humidity from Breton Island . 
100 

90 

a 80 

x 

>_ 70 

0 

r. 

60 

50 

40 

9 13 17 21 25 29 

September 1994 

Figure 4u . September 1994 hourly relative humidity from Breton Island . 
a 

0

.5 N 

m 

Q 4 

.. L 

O 

x 

a3 a 

Calibration ~ Calibration 

~C~--------C-~ 

i 

i 

i 

1 1 1 

1 1 1 

Questionable Data i i 

-----------------------

a . . ~ i 

11 13 15 17 19 21 23 

July 1994 

25 27 29 31 

Figure Sa. July 1994 hourly SOZ concentrations at PAL. 
R 

7 

6 

a 

N 5 

~'4 

0 

x 

2 

1 ! 1 

Calibration = ~ Calibration Calibration 

~Ct---------- ---- 

--

------------- ---p t ~ t ~ 4--------------------------------fi~~ 

I I 

i 

i 

I 

i 

j 

e 's t 

i ~ = s 

i 

i 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure Sb . August 1994 hourly SOZ concentrations at PAL. 

0 
Calibration 

-~--------------------fl 

End Deployment 

0. 

a. S 

N 

0 

00 

4 

J 

x 

3 

a 

13 17 21 25 29 

September 1994 

Figure Sc. September 1994 hourly SOZ concentrations at PAL. 
ON 00 

16 

14 

12 

.o 

a 10 

z 

4 

a. 

0 x 

6 

a 

a 

Service . Calibration t Calibration Calibration 

I 

i I ~ ! i 

Monitor Failure ~ Qu4flonable Data j 

~--------------------------------ice ~-------------------------- --------- 

-------------------- --------------- ---- 

i 

j 

i 

i 

i 

i 

i i 

i 

i 

I 

I 

I 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure Sd . July 1994 hourly NO concentrations at PAL. 

0 
9 

8 

7 

.0 6 

a a 

O 

two 5 

'C 4 

0 

a 

9

3 

2 

1 

Calibration ~ 

--------------~~ 

~ Calibration ~ Calibration 

~ ~-------------------t=i 

i ~ 1 I 

i 

i i 

i 

i 

i 

i 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure Se. August 1994 hourly NO concentrations at PAL. 

0 
8 

i 

----------------C=-~ Calibration 

Questionable Data -- -------------d 

J 

O 

7 

6 

.a 

a 

as 

°z 

~ 4 

7 

O 

x 

Q 3 

z 

0 

i 

i 

i 

End Deployment 

5 9 13 17 21 

September 1994 

25 29 

Figure Sf. September 1994 hourly NO concentrations at PAL. 
v 

r+ 

25 

20 

.a 

a 

0 15 

e°'n 

40 

Q 

r 0-0 

10 

a 

s 

of 

1 

Monitor Failure 

------------- ------------- 

i 

i 

i 

i 

Service ~ Calibration ~ Calibration 

ii 

Calibration 

i 

3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure Sg. July 1994 hourly NOZ concentrations at PAL. I 

Questionable Data 

< - --------------------I-----------------------

1 

1 

1 

1 

1 

I 

i 

i 
14- 

i i 

12 " 1 

1 

I 

1 

1 

1 

1 

1 

10- 

CL 

O 

z 8 ; 

6 

i 

4 

i 

i 

2 

i 

0 

1 3 5 

Calibration Calibration 

----- 

1 1 

1 1 

1 1 

1 1 

1 1 

1 1 

1 1 

1 1 

1 1 

I 1 

1 1 

i 

I 1 

Calibration j-________________-

1 

1 

1 

1 

1 

1 

1 1 

1 

1 

1 

1 

1 

1 

1 

1 i i 

i 

1 

i 

i 

I I 

7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure Sh. August 1994 hourly NOZ concentrations at PAL. 
w 

a 

N 

z 

a 

i. . 

x 

a 

a 

15 i 

------------------------------------f-4 

I 

Questionable ! Calibration ! 

Data = End Deployment 

I 

i 

i 

t 

i 

i 

i 

i 

i 

12 

9 

6 

5 9 13 17 21 

September 1994 

25 29 

Figure Si . September 1994 hourly N02 concentrations at PAL. 
36 

32 

28 

~ 24 

a a 

M 

20 

16 

x 

a 

N 12 

8 

4 

1 

Figure Sj . July 1994 hourly NO. concentrations at PAL. 

3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 
16 

12 

a. a 

H 

O 

z 

dg 

D O 

x 

a 

4 

0 

Figure Sk. August 1994 hourly NO,, concentrations at PAL. 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 
J 

20 

Questionable Date 

---------------

16 a 1 

0. 

M 

IZ 

z 

6 

W 

a 

0 

i 

c ~ Calibration 

---~~C------------- 1>i 

End Deployment 

i 

i 

i 

i 

5 9 13 17 21 

September 1994 

25 29 

Figure 51 . September 1994 hourly NO., concentrations at PAL. 
16 

12 

o. 8 

.a 

¢ a . 4 

0 

16 

12 

a. 

4 

J 

0 

16 

12 

11- 

~. s 

r.. 

4 

a 

0 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure gym. July 1994 hourly wind speeds at PAL and NOtL4 stations GDIL1 and BURI.l . 
lb 

~ 12 

"O 

N 

G. 

4 

a 

0 

16 

12 

't7 

O. H 

'~ 4 

00 

16 

12 

N 

o 

O 

L=+ Y 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Fijure Sn. August 1994 hourly wind speeds at PAL and NOAH stations GDIL1 and BURL1 . 
-1 

1.0 

12 

10 

v 

6 fl. 

4 

a 

2 

0 

12 

10 

b 

N 

n. 6 

cr: 

4 

0 

2 

0 

End Deployment 

1 5 9 13 17 21 25 29 

September 1994 

Figure 5o . September 1994 hourly wind speeds at PAL and NOAH station GDIL1. 
360 

315 

.0 270 

225 

180 

,~ 135 

a 90 

45 

0 

360 

315 

270 

225 

180 

a 135 

o ~ 90 

45 

0 

360 

c 315 0 

270 

.°= 225 

130 

135 

90 

45 

0 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure Sp . July 1994 hourly wind directions at PAL, and NOAA stations GDIL 1 and BURL 1 . 
360 

315 

0 

. 

270 

~, 

225 

180 

135 

a, 90 

45 

0 

360 

315 

270 

U 

N 225 

180 

a 135 

00 ~ 

`y 

90 

45 

0 

360 

c 315 0 

270 

225 

180 

135 

90 

45 

0 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure Sq. August 1994 hourly wind directions at PAL and NOAH stations GDILland BURL I . 
360 

315 

270 

225 

U 

N 

180 

'¢ 135 

a 

90 

45 

0 

360 

00 

315 

270 

a 0 

225 

a V 

180 

Q 135 

C7 

SO 

45 

0 

End Deployment 

1 5 9 13 17 21 25 29 

September 1994 

Figure Sr. September 1994 hourly wind directions at PAL and NOAA station GDII,1 . 
34 

32 

c~ 3 0 a 

~ 28 

~ 26 

a 24 

22 

20 

34 

32 

0 30 

28 

a 26 

A 24 

00 w 22 

20 

34 

32 

30 

-~ 

28 E Zs 

Za 

22 

20 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Fi?ure 5 s. July 1994 hourly air temperatures at PAL and NOA.A stations GDIL 1 and BURL 1 . 
34 

32 

0 30 

~ 28 

~ 26 

Q a 24 

22 

20 

34 

32 

0 30 

28 

26 

A 24 00 

~ 22 

20 

34 

32 U 

30 

12 28 

-' 26 

24 

22 

20 

1 3 5 '7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Figure St. August 1994 hourly air temperatures at PAL, and NOAA stations GDIL1 and BIJRLI . 
32 

30 

28 U 

0 

V 

Ha 26 

°" 24 

22 

20 

32 

00 

30 

u 28 0 

~ ' 26 

24 

?2 

20 

End Deployment 

1 5 9 13 17 21 25 29 

September 1994 

Figure 5u. September 1994 hourly air temperatures at PAL and NOAA station GDIL1. 
1028 

102 

1022 

1019 

1016 

a 1013 

00 

1010 

1028 

1025 

y 1022 

1019 

1016 

1013 

1010 

1028 

1025 

1022 

1019 

1016 

1013 

rIn 

1010 

w 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure Sv. July 1994 hourly atmospheric pressure at PAL and NOAH stations GDIL1 and BUItI.I . 
1026 

1022 

y 

1018 

a 

1014 

a 

1010 

1026 

1022 

a 1013 

v 

1014 

1010 

1026 

1022 

i 

a, 1018 

1014 

cA 

1010 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

Auaust 1994 

Figure Sw. August 199 hourly atmospheric pressure at PAL and NOAA stations GDIL 1 and BURL 1 . 
1026 

1024 

1022 

1020 

4 

1018 H 

1016 

d 1014 

a 

1012 

1010 

1008 

1026 

00 00 1024 

1022 

1020 

1018 

1016 

q 1014 

1012 

1010 

1008 

End Deployment 

1 5 9 13 17 21 25 29 

September 1994 

Figure 5x. September 1994 hourly atmospheric pressure at PAL anal NOAA station GDILl. 
100 

90 

80 

0 

x 70 

00 

60 

50 

40 4 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

July 1994 

Figure Sy. July 1994 hourly relative humidity at PAL. 
100 

90 

a 

80 

.'., 

x 

o 

70 

a 

60 

50 

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 

August 1994 

Fijure Sz. August 1994 hourly relative humidity at PAL. 
100 

95 

90 

a 

T1 

'~ 85 

x 

80 

a 

75 

70 

65 

End Deployment 

1 5 9 13 17 21 25 29 

September 1994 

Figure Saa. September 1994 hourly relative humidity at PAL. 
RESULTS AND DISCUSSION 
RESULTS AND DISCUSSION 

1. Introduction 

The three air quality and meteorological monitoring stations deployed during the summer of 

1994 were all located within an area centered on the Breton Sound in the northeast Gulf of Mexico. 

In view of this fact, it was anticipated that nearly the same meteorological conditions would exist at 

each site . An examination of the time series plots of the meteorological parameters shows that this 

was the case (Figs . 3d - 3m for Gosier, 4m -4u for Breton, and Sm -Saa for PAL). For further 

verification, the data records were compared to those obtained at several nearby NOAA stations (see 

Fig. 1 for station locations) . NOAH buoy 42007 is located near the northern tip of the Chandeleur 

Islands at approximately 30.1°N 88.8°W. The 12 m discus buoy is moored in 13 m of water and 

records meteorological and oceanographic data hourly . GDII,1 and BURL1 are Coastal-Marine 

Automated Network (C-MAN) stations located at the Grand Isle U.S. Coast Guard Station and at 

the entrance to Southwest Pass, Louisiana, respectively. It can be seen from the figures that generally 

homogeneous conditions prevailed over the study area even though several frontal passages and 

storm systems were experienced during the deployment. (Note that an apparent offset exists in the 

Breton and PAL pressure records, however the trends are in good agreement.) 

The three stations were deployed in areas that have been designated as Class I (Gosier and 

Breton) and II (PAL) by the EPA. National Ambient Air Quality Standard (NAAQS) maximums for 

the monitored pollutants are listed in Table 8, while Prevention of Significant Deterioration (PSD) 

Increments are given in Table 9. Due to the timing and duration of this study and the unavailability 

of a baseline measurement, it is not valid to compare results with the PSD increments ; however they 

are presented here for reference. 

2. Gosier Island 

As described previously, the Gosier Island station was plagued by several problems during 

its deployment, not the least of which was its dependence on battery power. This forced the 

implementation of a non-continuous measurement scheme in which air quality was sampled only once 

(5-minute average) an hour. The highest concentration of SOZ recorded was 22 ppb on 14 July at 

1000 iTTC with winds of 3 .2 m s'' from 188°. Note that this measurement was obtained before the 

SOZ Analyzer was calibrated on-site. After calibration, the highest concentration recorded during the 

rest of the deployment was 2 ppb, which may reflect background noise or zero fluctuation. With 

these considerations, extensive analysis of this data record was not attempted. 

In order to investigate the possibility of acid rain deposition, pH measurements were made 

in a pond adjacent to the air quality station. Salinity (conductivity) and water temperature were also 

recorded. The pond was shallow (less than 2 foot estimated) but appeared to supply an important 

feeding and nesting area for many of the protected marine waterfowl . The sensors were attached to 

95 
Table 8 . 

U.S . Federal Primary and Secondary Ambient Air Quality Standards 

Source : 40 CFR § 50, July 1992 

(From Boubel et al ., 1994) 

Pollutant 

Type of 

Standard 

Averaging 

Time 

Frequency 

Parameter 

Concentration 

Pg / m3 ppm 

Sulfur oxides (as Primary 24 hr Annual Maximum' 365 0.139 

sulfur dioxide) 

1 yr Arithmetic Mean 80 0.030 

Secondary 3 hr Annual Maximum' 1300 0.494 

Nitrogen dioxide Primary and 1 yr Arithmetic Mean 100 0 .053 

Secondary 

"`Not to be exceeded more than once per year 

96 
Table 9. 

U.S . Federal PSD Concentration Increments 

Source: 40 CFR § 51 .166, July 1992 

(From Boubel et al ., 1994) 

Increment 

Pollutant gg / m3 ppm 

Class I 

SOZ 

Annual Arithmetic Mean 

24-hr Maximum 

3-hr Maximum 

NOZ 

Annual Arithmetic Mean 

2 0.001 

5 0.002 

25 0.010 

2.5 0.001 

Class II 

SOZ 

Annual Arithmetic Mean 

24-hr Maximum 

3-hr Maximum 

NOZ 

Annual Arithmetic Mean 

20 0.008 

91 0.035 

512 0.195 

25 0 .013 

97 
a pipe and submerged in approximately 6 - S inches of water (the water level was noted to have 

dropped considerably by the end of July). Measurements obtained show that the water was brackish ; 

however pH values were generally greater than 8 (more alkaline). Diurnal variations are evident in 

the time series plot (Fig. 3m), particularly after 12 July. Positive correlation of pH and temperature 

is seen, while salinity appears inversely related due to evaporation and cooling effects. 

Passive air quality sensors (Ogawa and Palmes tubes) were exposed throughout the 

deployment . Analysis was later performed by the Harvard School of Public Health through a subcontractor, Environmental Science and Engineering, Inc. Their results are given in Tables 10 and 11 . 

Long exposure times and improper storage of the tubes in all likelihood invalidates this data. 

3. Breton Island 

Tables 12 and 13 present the daily maximum and average concentrations of S02 and NO2, 

respectively, as recorded at Breton Island . Monthly maximum hourly, 3-hourly, and daily 

concentrations are listed in Table 14. From Fig. 6, it is apparent that ambient S02 levels are well 

below the NAAQS at this site . 

It has been shown that meteorological conditions were consistent in the study area. 

Therefore, the Gosier Island wind record has been applied in the Breton analysis . Monthly wind roses 

with average pollutant concentration are shown in Figs. 7 - 10 . In July and August, the highest NOZ 

concentrations were from the northeast quadrant with an average value of approximately 12 - 13 ppb. 

This level dropped to near 5 ppb in September, with highest concentrations from the south and 

southwest. Average SOZ concentrations are even lower in August, with the maximum being about 

3 ppb from the south. 

The frequency distribution of the entire NOZ record is illustrated in Fig. 11 and Fig. 12 for 

SOz. Highest concentrations were from the north and northeast during the study period, however 

the majority of hourly measurements were less than 10 ppb for N02 and 5 ppb for S02. 

The station record for N02 indicates that, during the deployment, several short-term episodes 

of higher than average NOZ levels were observed. Table 15 shows those cases in which hourly NOZ 

concentrations exceeded 18.2 ppb . Assuming the data is normally distributed, this should include 

only the highest 0 .3% of the record (see Spiegel, 1961, p. 71) . In most cases, the prevailing wind 

directions were from the east-northeast. The high ratio of NO to NOX is an indication of the chemical 

conversion which is a function of the residence time of the pollutant in the air mass (i .e., high ratio -

short time, nearby source) since the conversion of NO to NOZ is fairly rapid in the troposphere 

(Manahan, 1993). High levels are typically observed for only a few hours (daily maximums are about 

30% or less of the hourly maximums). Unfortunately, a complete emissions inventory for the area 

during our measurement period has not been included here. Potential local sources are mostly mobile 

(pleasure or commercial vessels) or semi-mobile (generators on moored houseboats in Breton 

98 
1VVUVU 

U 

C 

O 

U 

N 

O 

1000 

100 

loo 

10 

Highest SOZ Concentrations 

Breton 

PAL 

0 Note: For SO 2; 1 ppb = 2.6 gg/m' 

° 

o, .so 

1 Hour 

3 Hour 

24 Hour 

0.01 0.1 1 10 100 

Averaging Time, Hours 

I 

F igure I 6 . NAAQS st indards and maximurnS02 concentrations at PAL and Breton Island. 

99 
Table 10 . 

Gosier Island Ogawa (SO)Passive Data 

0 0 

CSI Design. Harvard Design. Time On Time Ofd Total Hours Net P1113 S02 

G001 ESC 1 6/29 Missing -- 

1631 

G003 ESC 3 7/7 7/13 150.8 3 .4 

1140 1825 

G005 ESC 5 7/13 7/28 350 2.9 

1827 0830 

G007 ESC 7 7/28 8/5 196.3 3 .3 

0830 1244 

G009 CSC 9 8/5 8/17 285.2 9.5 

1246 0955 

G013 ESC 13 8/17 8/24 170.4 2.0 

0955 1240 

G015 ESC 15 8/24 (8/23)' 8/31 166.2 (190) 2.1 

1241 1058 

G017 ESC 17 8/31 9/8 193.2 0.8 

1058 1208 

G019 ESC 19 9/8 9/26 438 6.2 

1208 1840 

Dates and times in parentheses are incorrect, but were used in Harvard's chemical analysis . 

NOTE: Ogawa tube #'s 11, 12, and 21 were not exposed. 
Table 11 . 

Gosier Island Palmes (N02) Passive Data 

0 

CSI Design. Harvard Design . Time On Time Off Total Hours Mean Conc. N02 PPI3 

G001 6/29 7!7 187.2 

1630 1140 

6003 ESC-003 7/7 7/13 150.8 449.4 

1140 1825' 

G005 ESC-005 7/13 7/28 350 5 .58 

1827 0830 

G007 ESC-007 7/28 8/5 196 .2 5 .74 

0835 1244 

G009 ESC-009 8/5 8/17 285 .2 5.08 

1246 0955 

GU 11 ESC-011 8/17 8/24 170.8 5.82 

0955 1240 

G015 ESC-015 8/24 (8/23)+ 8/31 166.3 (190.3) 5 .10 

12'11 1058 

G017 CSC-017 8/31 9/8 193 .2 13 .05 

1058 1208 

6019 ESC-019 9/8 9/26 438.5 3 .75 

1208 1840 

Tube found on beach near tower. 

i Dates and times in parentheses are incorrect but were used in Harvard's chemical analysis . 

NOTE: Palmes tubes # 13, 14, and 21 were not exposed. 
Table 12. 

Breton Island Daily SOZ Maximums and Averages (ppb) 

Julv 1994 Au st 1994 September 1994 

Dav Maximum Average Maximum Average Maximum Average 

1 1 0 1 0.9 0 0 

2 6 1 .8 0 0 1 0.3 

3 12 1 .8 1 0.1 

4 3 0.3 0 0 

5 0 0 0 0 

6 0 0 0 0 

7 0 0 2 0.1 

0 0 

0 0 

10 1 0 

11 1 0.1 

12 0 0 

13 17 2 

14 10 0.7 

15 11 0.9 

16 7 0.4 

17 3 0.4 

18 1 0.5 

19 2 1 

20 2 1 .1 

21 1 0.6 

22 9 1 .5 

23 25 2.4 

24 9 2.1 

25 5 0.4 

26 0 0 

27 1 0.1 

28 11 4.2 

29 S 2.8 

30 2 1 .1 

31 1 0.9 51 3.6 

Number Hours 255 637 41 

Maximum 12 51 1 

-Afith-Mean 1 _ 1 .2 0.7 1 0.1 

Total Samples = 933 

% Of Possible Observations = 44.2 

102 
Table 13 . 

Breton Island Daily NOZ Maximums and Averages (ppb) 

Jul 1994 Au 1994 S ember 1994 

Day Maximum Average Maximum Average Maximum Average 

1 3 0.5 17 5.9 11 3.5 

2 36 9.5 7 1 .2 10 3.6 

3 30 7.3 5 1 .1 16 3.8 

4 8 1 .2 2 1 3 1 .4 

5 5 0.6 5 1 .7 2 0.7 

6 10 0.8 22 6.8 4 0.8 

7 11 1 .1 36 7.8 11 2.7 

8 13 3 .8 6 2.8 

9 S 2 .5 S 1 .9 

10 31 7.4 4 1 .8 

11 45 12 3 1 .9 

12 6 1 .4 3 1 .7 

13 33 7.7 2 1 .1 

14 4 2.3 11 4.4 1 0.5 

15 4 2.1 16 4.6 2 0.8 

16 12 3.1 11 6.4 31 9.6 

17 9 4 19 6.9 25 9.3 

18 11 4.9 6 2.6 7 2.9 

19 13 5.1 7 33 13 3.9 

20 15 4.7 6 2.8 4 2.1 

21 8 4 7 2.3 11 1.7 

22 9 4.2 11 5.5 13 3.2 

23 15 5.8 13 5.2 11 3.7 

24 15 5.1 29 7.7 10 5.5 

25 7 3.7 28 4.5 8 3.6 

26 7 3.8 4 2 6 3.4 

27 6 4.1 8 3.5 

28 8 3.3 

29 59 9.4 

30 18 3.8 

31 

1 

S 1 .5 8 3.6 

Number Hours 577 637 615 

Maximum 59 45 31 

Arith_Mean 39 4.5 3 .0 

Total Samples = 1829 

Of Possible Observations = 86 .6 

103 
Table 14. 

Breton Island 1994 Pollutant Maximums 

Month Pollutant % Averaging 

Period 

Maximum 

ppb 

Average Wind 

Speed / Direction 

Date / Tune UTC 

1 hr 12 3.2/9 7/3/94 @ 1300 

S02 34.3 

3 hr 8.3 

6.3 

5.2/311 

8.3/19 

7/28/94 @ 0600- 

7/28/94 @ 1100 

July 

r 24 hr 4.2 

2.8 

5.3/340 

2.7/358 

7/28/94' 

7/29/94 

1 hr 59 3 .4/317 7/29/94 @ 0200 

NO Z 77.6 3 hr 31 3.4/51 7/2/94 @ 1000 

24 hr 9.5 4.5/73 7/2/94 

1 hr 51 

25 

2.4/195 

1 .7/143 

8/31/94 @ 0600- 

8/23/94 @ 1500 

S02 85.6 3 hr 21 .3 

13 .3 

2.6/192 

6.2/52 

8/31/94 @ 0800- 

8/13/94 @ 1600 

August 24 hr 2.4 2.2/206 8/23/94 

1 hr 45 6.4/53 8/11/94 @ 1600 

NO, 85.6 3 hr 28.3 5.6/50 

6.3/54 

8/11/94 @ 1200 

and 1600 

24 hr 12 5.3/76 8/11/94 

1 hr 1 6.2/312 9/2/94 @ 1100 

S02 6.6 3 hr 1 5 .1/352 9/2/94 @ 1600 

S b 

24 hr 0.3 4.8/296 9/2/94 

eptem er 

1 hr 31 3.3/200 9/16/94 @ 1300 

NO, 98.7 3 hr 24 3.4/197 9/16/94 @ 1500 

24 hr 9.6 5.7/175 9/16/94 

Average concentration values may reflect residual measurements from instrument calibration nuts . 

NOTE: Wind speed in m sec-' and direction in degrees. 

104 
Figure 7 . July 1994 wind rose from Gosier Island . Solid bar denotes percentage of speeds greater 

than 5 m sec' . Solid line is average NOZ concentration in ppb at Breton Island (57G 

samples, 77.4% of month). 

105 
ZS"/n 

'r 

In -_ 1 5^/0 

i 

" . 

------- 01101 

5 ppb j. j 

15 PpU 

------------- 

Figure 8. August 1994 wind rose from Gosier Island . Solid bar denotes percentage of wind speeds 

greater than 5 m sec-' . Solid line is average N02 concentration in ppb at Breton Island 

(632 samples, 84 .9% of month) . 

106 
',10"/n 

%20"/0 

~III \_ `10"/. 

\ -

i 

to`pav _ - 

20 nob j~ 

------------- 

Figure 9 . September 1994 wind rose from Gosier Island. Solid bar denotes percentage of wind 

speeds greater than 5 m sec-1. Solid line is average NOZ concentration in ppb at Breton 

Island (611 samples, 98 .6% of possible record). 

107 
.~25% 

j - 15"/0 

`'S"/o 

~~. : .. . 

. . 

.~~ 

15 ppb 

Figure 10. August 1994 wind rose from Gosier Island . Solid bar denotes percentage of wind speeds 

greater than 5 m sec' . Solid line is average SOZ concentration in ppb at Breton Island 

(632 samples, 84.9% of month) . 

108 
Figure 11 . Frequency distribution of N02 (in ppb) at Breton Island during the period of 1 July to 26 

September 1994 based on Gosier Island winds (1819 samples, 86 .2% of possible record). 

Bar is divided into 0-10 ppb (clear), 10-20 ppb (hatched), and >20 ppb (solid) . 

109 
Figure 12. Frequency distribution of SOZ (in ppb) at Breton Island for the months of July and August 

1994 based on Gorier Island winds (887 samples, 59.6% of possible record) . Bar is 

divided into 0-5 ppb (clear), 5-10 ppb (hatched), and >10 ppb (solid). 

110 
Table 15. 

Events of Breton Island NO2 Concentration > 18 .2 ppb 

NOZ NO NOx NO / NO,, WS m s' Previous 6 Hour 

Date / Time Ratio / WD WS / WD 

7/2/94 0800 32 107 139 0.8 3 .1/62 3 .4/87 

0900 25 68 94 0.7 3 .4/60 3 .3/83 

1000 36 176 213 0.8 3 .7/51 3 .3/77 

1200 23 87 111 0.8 5 /39 3 .8/53 

1300 25 84 109 0.8 5.2/33 4.1/47 

1400 28 106 134 0.8 5.4/42 4.5/43 

1500 19 89 109 0.8 5.9/58 4.9/43 

7/3/94 0200 30 71 101 0.7 5.6/51 4.6/73 

0300 23 51 74 0.7 6.3161 4.7/68 

0600 19 39 58 0.7 5.6/54 5.9/57 

7/29/94 0200 59 44 103 0.4 3.4/317 1 .5/276 

1800 23 60 83 0.7 2.3/35 2.9/21 

8/6/94 0100 22 7 28 0.3 4.9/326 2.3/135 

8!7/94 1400 36 10 46 0.2 2.8/22 2.2/321 

2000 24 67 91 0.7 3.9/66 2.6/36 

8/10/94 0900 31 71 102 0.7 4.2/36 3 .7/68 

1300 19 36 55 0.7 5 /33 4.2/34 

1400 27 67 95 0.7 5.3/46 4.5/33 

8/11/94 1000 21 75 97 0.8 5.3/53 4.1/65 

1100 22 49 71 0.7 5.7/52 4.5/59 

1200 42 148 191 0.8 5.9 /46 5/54 

1300 20 51 72 0.7 62 /52 5.3/52 

1500 22 47 69 0.7 6.4 /53 5.9/52 

1600 45 128 174 0.7 6.4 /'53 6.1/52 

1900 25 102 128 0.8 6/94 6.2/74 

8/13/94 1300 21 171 192 0.9 5.7 /'44 5.1/65 

1400 25 182 208 0.9 6.4 /'51 5.5/60 

1500 33 218 252 0.9 6.3 /51 5.8/58 

1600 23 139 163 0.9 6/54 5.9/57 

1700 23 160 184 0.9 5.9 /57 6.1/54 

8/17/94 1100 19 2 22 0.1 3 .1 /339 4.3/326 

8/24/94 1400 29 110 141 0.8 2 .8 /43 1 .7/115 

1500 28 101 130 0.8 3 .5 15l 1 .9/93 

1600 22 70 92 0.8 M / M 1 .9/93 

8/25/94 1600 28 78 108 0.7 6.2 /54 5 .3/57 

9/16/94 1300 31 229 261 0.9 3.3/200 4.4/195 

1400 19 99 119 0.8 3.4/195 4/201 

1500 22 130 152 0.9 3.4/196 3 .7/203 

1700 20 88 108 0.8 3.3/201 3 .4/202 

2100 20 61 81 0.8 5/190 4/204 

2200 24 100 124 0.8 5.8/191 4.3/201 

9/17/94 0500 20 109 130 0.8 6.1/201 5.9/201 

0600 21 109 131 0.8 6/206 5.9/203 

0700 23 108 131 0.8 5.6/202 5.8/204 

0800 25 128 153 0.8 5.6/208 5.8/205 

111 
Sound), but frequency or amount of traffic is not know. Another possible local source is the 

generator at the Kerr-McGee facility on Breton Island which is in continuous operation. 

Passive sampler data for Breton Island as provided by the Harvard School of Public Health 

is given in Tables 16 and 17 with the same considerations as at Gosier. 

4. Pass-A-Loutre 

Observed ambient levels of both SOZ and N02 at the PAL station were lower than those at 

Breton during the study period . Daily maximums and averages for SOZ and N02 are in Table 18 and 

19, respectively . Monthly hourly, 3-hourly, and daily maximums are in Table 20. 

Wind roses with average pollutant levels are shown in Figs. 13 - 16. Highest levels of NOZ 

occurred from the southwest and northwest quadrants in July, and again from the northwest in 

August. Average N02 values were less than 5 ppb. SOZ appeared to be more evenly distributed; 

however average concentrations were near to zero . 

Figures 17 and 18 display the frequency distributions for the entire record of NO2 and SO2, 

respectively . Highest concentrations of N02 were from northwest and southwest, while highest S02 

concentrations came from the north. The majority of all measurements were 5 ppb or less . 

Table 21 is constructed similar to Table 15, but for PAL. The NO/NO,, ratios here are much 

lower, suggesting a more aged air mass (distant source); however it should be noted that the wind 

speeds were generally very light. The highest ratios appear to be associated with westerly transport. 

A possible cause may be ship traffic in the heavily utilized South and Southwest Passes of the 

Mississippi River delta. 

5. Radiosondes 

Atmospheric profiles obtained by radiosondes were analyzed to determine the mixing heights 

prevailing over the study area. Profiles of the lower 1000 - 2000 m of potential temperature (8) and 

mixing ratio (q) for each sounding are shown in Figs. 19a - c. In a well-mixed boundary layer, 8 and 

q remain nearly constant with height until reaching the top of the layer, at which point there is usually 

rapid increase of 8 and decrease of q. Each profile was examined to identify the height where this 

change (in slope) occurred. 

Assuming the presence of cumulus cloud (which often prevail over the marine layer), Garratt 

(1992) has shown that the mixing height h = LCL, the lifting condensation level. The LCL may be 

estimated (see McIlveen, 1986) by 

HeQ = 125 (T,, Td,wl 

112 
where H.a is the mixing height over the water surface, and T ,j, and T , are the air and dewpoint 

temperatures (°C) . If the clouds are stratiform, then the mixing height extends to the cloud top rather 

than base. 

Table 22 lists all heights as determined by the methods described . LCLP is obtained from the 

plot of the profile on a Skew-T Log-p thermodynamic diagram, while LCLc was calculated from Eq. 

(1) and h is from 8 and q. If one accepts a root mean square error of approximately 71 m, then Eq. 

(1) may be used to estimate the LCL over our study area. The lifting condensation levels and mixing 

height estimates for each profile are generally within 100 - 200 m, however excellant agreement is 

found between the mean LCLp (507 m) and the mean mixing height (505 m). Since heights h and 

LCLp are measured directly by radiosonde which LCL, is derived from theoretical considerations, it 

should be possible to refine Eq. (1) to more accurately represent our study area given further 

investigation and measurements. At this point, considering the upper-air measurement void which 

exist over the Gulf of Mexico, Eq. (1) is offered here as a first approximation. Regardless, all of the 

heights found through this analysis are well below the climatic mean for summer as given by 

Holzworth (1972) . 

113 
Table 16 . 

Breton Island Ogawa (SOZ) Passive Data 

CSI Design . Harvard Design . Time On Time Off Total Hours Net PPB S02 

B002 ESC 2 6/30 7/7 171 .9 4.7 

1158 1550 

B004 ESC 4 7/7 7/13 149.3 5.2 

1550 2105 

B006 ESC 6 7/13 7/27 (7/26)+ 328.9 (305) 26.0 

2110 1405 

B008 ESC 8 7/27(7/26) 8/5 218.9 (243) 9.5 

1409 1706 

13010 ESC 10 8/5 8/16 266.6 9.1 

1708 1946 

B014 ESC 14 8/16 8/23 167 .5 1 .8 

1950 1918 

8016 ESC 16 8/23 8/30 168 4.5 

1921 1919 

B018 ESC 18 8/30 9/7 192.5 1 .2 

1920 1948 

B020 ESC 20 9/7 9/26 455 12 .6 

1949 1852 

B022 ESC 22 9/26 10/4 183 .8 9.3 

1855 1040 

B023 10/4 10/13 220.8 

1040 1525 

Dates and times in parentheses are incorrect, but were used in Harvard's chemical analysis . 

NOTE: Ogawa tube #'s 11, 12, and 21 were not exposed. 
Table 17. 

Breton Island Palmes (N02) Passive Data 

... 

CSI Design. Harvard Design. Time On Time Off Total Hours Mean Cone. N02 I'I'13 

B002 CSC-002 6/30 7/7 171 .9 9.38 

1157 1550 

B004 ESC-004 7!7 7/13 149.3 15 .56 

1550 2104 

B006 ESC-006 7/13 7/27 (7/26)' 329 (304) 8.66 

2108 1405 

B008 ESC-008 7/27 (7/26) 8/5 219 (243) 6.62 

1409 1706 

13010 ESC-010 8/5 8/16 266.6 11 .91 

1708 1946 

B012 ESC-012 8/16 8/23 167.5 13 .64 

1950 1918 

B016 ESC-016 8/23 8/30 168 7.92 

1921 1919 

13018 ESC-018 8/30 9/7 192.5 7.28 

1920 1948 

B020 ESC-020 9/7 9/26 455 5 .52 

1949 1852 

B022 ESC-022 9/26 10/4 183.8 4.86 

1855 1040 

8023 10/4 10/13 220.8 

1040 1525 

'Dates and times in parentheses are incorrect, but were used in Harvard's chemical analysis . 

NOTE: Palmas tubes #'s 13, 14, and 21 were not exposed. 
Table 18. 

Pass-A-Loutre Daily SOZ Maximums and Averages (ppb) 

Julv 1994 Au 1994 September 1994 

Dav Maximum Average Maximum Average Maximum Average 

1 1 0.8 2 0.1 0 0 

2 5 0.3 0 0 4 0 .8 

3 0 0 0 0 7 1 

4 1 0 0 0 1 0.1 

5 0 0 0 0 0 0 

6 0 0 3 0.7 0 0 

7 2 0.4 0 0 2 0.3 

8 1 0.5 0 0 0 0 

9 1 0.1 2 0.3 0 0 

10 0 0 1 0.1 0 0 

11 1 0 0 0 0 0 

12 1 0.1 0 0 0 0 

13 0 0 3 0.2 

14 1 0.2 7 1 .4 

15 0 0 6 1 .3 

16 0 0 4 1 

17 1 0.4 4 1 

18 2 0.8 2 0.1 

19 1 0.4 1 0 

20 2 03 0 0 

21 1 0.3 1 0.1 

22 0 0 3 0.3 

23 1 0.1 1 0.1 

24 0 0 1 0.2 

25 1 0 1 0 

26 1 0 0 0 

27 1 0 0 0 

28 7 1 .4 0 

- 

0 

29 3 1 0 0 

30 1 0.1 1 0.1 

31 1 0 2 0.3 

Number Hours 709 729 277 

Maximum 7 7 7 

4f;th_Mean n ? a2 0.2 

Total Samples = 1715 

Of Possible Observations = 97 .9 

116 
Table 19. 

Pass-A-Loutre Daily N02 Maximums and Averages (ppb) 

Julv 1994 Au 1994 S tember 1994 

Dav Maximum Average Maximum Average Maximum Average 

1 4 1 .7 5 1 .8 

2 3 0.9 11 4 

3 3 0.5 14 4.2 

4 3 0.5 4 1 .2 

5 5 1 .7 2 0.6 

6 10 3.2 1 0.5 

7 23 3.8 4 2 3 1 .2 

8 9 1 .5 3 1 .2 9 2.4 

9 7 1 .3 6 1.4 2 1 .4 

10 5 1 .3 4 1.5 2 1 .2 

11 5 1 .5 8 13 2 0.6 

12 14 1 .9 4 2.2 5 1 .8 

13 6 1 .3 3 1.3 

14 10 1 .4 10 3 

15 7 0 .4 9 3 .2 

16 4 0.3 12 5 

17 6 1 .4 13 5.1 

18 11 1 .8 5 1 .6 

19 3 1 9 2.4 

20 6 1 .2 1 0.3 

21 7 1 .3 3 0.7 

22 4 23 9 3.5 

23 12 4.1 6 2.6 

24 11 4.8 3 1 .8 

25 9 3 .3 S 1 .5 

26 9 2.9 3 0.8 

27 15 3 4 0.9 

28 10 2.9 3 0.8 

29 15 3.3 2 0.6 

30 3 1 .8 5 2.2 

31 9 2 10 1 .8 

Number Hours 570 729 277 

Maximum 23 13 14 

Arith-Mean 2 1 .R 1 .7 

Total Samples = 1576 

Of Possible Observations = 97.8 

117 
Table 20 . 

Pass-A-Loutre 1994 Pollutant Maximums 

Month Pollutant % Averaging 

Period 

Maximum 

ppb 

Average Wind 

Speed / Direction 

Date / Tune UTC 

1 hr 7 3.5/8 7/28/94 @ 1000 

SO2 97.9 3 hr 4 3 .5/12 7/28/94 @ 1200 

24 hr 1 .4 2.6/334 7/28/94 

July 

I hr 23 0.5/324 7x7/94 @ 2300 

NO, 78.7 3 hr 11 0.5/356 7/8/94 @ 0 100 

24 hr 4.8 1 .1/260 7/24/94 

1 hr 7 3 .6/355 8/14/94 @ 2 100 

SO2 98 3 hr 5 .7 4/349 8/14/94 @ 2 100 

24 hr 1 .4 2.3/354 8/14/94 

August 1 hr 13 0.5/325 8/17/94 @ 1000 

NO2 98 3 hr 11 .7 3 .8/316 

0.8/322 

8/16/94 @ 0400 and 

8/17/94 @ 1100 

24 hr 5.1 2.3/262 8/17/94 

1 hr 7 2.1/330 9/3/94 @ 0500 

SO2 98.2 3 hr 4.7 1 .9/322 9/3/94 @ 0700 

24 hr 1 2,2/336 9/3/94 

September 

1 hr 14 1.4, 1 .3 /312,319 9/3/94 @ 0800, 0900 

N02 98.2 3 hr 13 1 .5/314 9/3/94 @ 0900 

24 hr 4.2 ~ 2.2/336 ~ 9/3/94 

NOTE : Wind speed in m sec' and direction in degrees. 

118 
i 

,-

\ . 

MOMM 

5 ppU 

10 ppb - 

. . . . . . . . . ,~ \ . . . . . ,f_ . . . . . . . . . . . 

i 

i 

~ .. . / . . . .-----

.

. . . .~ 

Figure 13 . July 1994 wind rose from PAL. Solid bar denotes percentage of wind speeds greater than 

5 m sec'. Solid line is average N02 concentration in ppb (569 samples, 78 .6% of month). 

119 
- ~~25"/n 

--- ~ - 

\ - ~5/0 

. . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

--------- ------- \\ \\ 

I S ppb / '. 

Figure 14. August 1994 wind rose from PAL. Solid bar denotes percentage of wind speeds greater 

than 5 m sec' . Solid line is average N02 concentration in ppb (729 samples, 98% of 

month) . 

120 
Figure 15 . July 1994 wind rose from PAL. Solid bar denotes percentage of wind speeds greater than 

5 m~sec' . Solid line is average S02 concentration in ppb (724 samples, 97 .9% of month). 

121 
. ._ . . .. . . . . . . ..F .. . . . . . . .. . .. . . . 

j , - ~~~_5"/0 

j 

i 

. . . . . . .. .. . t . . .. ... .. . .. . .. . .. . . . . .~-

- ---- -- 

. . . . .. .. . . . .. . . . . \ ~ ~~ ~\~\ 

i 5 ppb 

10 ppU 

i 

Figure 16 . August 1994 wind rose from PAL. Solid bar denotes percentage of wind speeds greater 

than 5 m sec-' . Solid line is average S02 concentration in ppb (729 samples, 98% of 

month). 

122 
Figure 17. Frequency distribution of NOZ concentration (in ppb) at PAL during the period of 1 July 

to 12 September 1994 (1574 samples, 89.9% of possible record) . Bar is divided into 0-5 

ppb~(clear), 5-10 ppb (hatched), and >10 ppb (solid) . 

123 
Figure 18 . Frequency distribution of S02 concentration (in ppb) at PAL during the period of 1 July 

to 12 September 1994 (1715 samples, 97.9% of possible record). Bar is divided into 0-5 

ppb,(clear) and >5 ppb (hatched). 

124 
Table 21 . 

Events of Pass-A-Loutre N02 Concentrations > 8.8 ppb 

NO, NO NO,, NO / NOx Previous 6 Hour 

Date / Time Ratio WS m sec-'/ WD WS / WD 

7/7/94 2300 23 11 35 0.3 o.5/324 2.1/189 

7/8/94 0000 9 5 16 0.3 0.6/6 1 .9/235 

7/12/94 0300 14 3 19 0.2 1 .7/301 2.9/200 

7/14/94 0400 10 5 16 0.3 2/132 3.2/166 

7/18/94 0600 9 1 11 0.1 1/245 0.2/178 

0700 11 3 15 0.2 1/244 0.3/191 

7/23/94 0800 12 0 12 0 1 .4/227 0.9/214 

0900 9 0 9 0 0.6/227 1/223 

1000 1O 0 10 0 0.8/252 1/229 

7/24/94 0100 11 0 10 0 0.6/236 2.8/212 

0200 11 1 11 0.1 0/230 2.7/219 

7/25/94 0300 9 0 8 0 :2 .5 / 223 2.8/232 

2300 9 12 20 0.6 .3 .8/236 4/247 

7/26/94 0100 9 0 9 0 3.5/226 3 .9/237 

7/27/94 1100 15 12 29 0.4 6.8/232 5.6/228 

7/28/94 0700 9 1 11 0.1 3 .5 / 323 2.6/300 

0800 10 1 12 0.1 3 .9/336 2.9/312 

7/29/94 1000 9 1 12 0.1 0.2/340 0/354 

1100 15 1 18 0.1 1 .2/347 0.3/351 

7/31/94 2300 9 1 12 0.1 1 .2/228 1 .7/243 

8/6/94 1000 10 1 13 0.1 0.4/299 0.3/323 

1400 9 2 12 0.2 1 .4/341 0.9/321 

8/14/94 1300 10 2 13 0.2 3 .8 / 318 3/327 

8/15/94 1100 9 1 11 0.1 1 .8/336 1 .4/311 

8/16/94 0200 1l 0 12 0 4.2/311 3.9/274 

0300 12 0 14 0 .3 .9/313 4,1/281 

0400 12 0 13 0 3 .2 / 323 4/294 

8/17/94 0100 10 0 11 0 3 .6 / 224 3 .2/242 

0200 10 0 11 0 .3 .2/225 3 .2/240 

0900 11 0 12 0 1 .5/334 2.3/267 

1000 13 0 15 0 0.5/325 1 .9/283 

1100 11 0 13 0 0.3/308 1 .4/296 

1200 9 1 12 0.1 0.2/341 1 .1/311 

1300 10 2 13 02 0.2/31 0.8/335 

8/19/94 0900 9 0 11 0 0.5/234 0.7/226 

8/22/94 0800 9 1 11 0.1 0.5/289 0.5/214 

8/31/94 0000 10 1 12 0.1 0.5/223 1 .9/210 

9/2/94 0500 11 1 13 0.1 0.5/340 1 .4/280 

0600 10 2 14 0.1 0/340 1 .1/296 

1200 9 6 16 0.4 0.8/349 0.1/342 

9/3/94 0600 12 0 13 0 1 .8/323 2.6/310 

0700 11 0 13 0 1 .8/312 2.4/307 

0800 14 1 16 0.1 1 .4/312 2.1/315 

0900 14 2 17 0.1 1 .3/319 1.9/318 

9/8/94 1100 9 3 12 0.3 0/150 0.2/155 

1300 9 1 11 0.1 0.4/7 0.1/97 

125 
4sm / k6 

10 11 12 13 14 15 16 17 

- ------- - --

-- f 

_ _ '

-- ---

-- - ------- - ----- 

---_----I 

SIR] 1216 LT 

26 27 28 29 

e, °c 

q, sm/rs 

- -- -- - - -- ,y] 

---- -------- -----

------------ ------------------ ---------------

S2R2 1900 LT 

0 

27 28 29 30 

e, °c 

4Em/ rB 

10 13 16 

r--_-----_ -~--St'------~ 

S2R3 0631 LT 

-~- 

41'' 

0 

28 29 30 31 32 33 34 76 27 28 29 

e, °c e, ~c 

Figure 19. Atmospheric profiles of potential temperature (A, X-line) and mixing ratio (q, o-line) 

versus height in m over our study area. Light solid line denotes mixing height h, light 

dotted line is LCLp, and heavy dashed line is LCL~ (see text for details) . 

126 

48mI k8 

19 _ to . . 1R ._ is ., . on 

lip 

--- -------- ------------------- --------------- 

52R1 1558 LT 

--1 a 
9.&n / rB 

10 12 14 16 Is 

---- 

-------- --------------- ------- 

SZR4 1902 LT 

.----y 

25 27 29 31 33 

e, °c 

q.pn/k6 

13 14 IS 16 17 18 19 20 

q.sm~ra 

,~ 8 10 12 14 1e 1 a 20 

`b 

--

-- ----------- ----

---- ------------------------------------- -------- 

S2R5 0706 LT 

O 

?A 26 28 30 

8, °C 

a. sm / to 

14 15 16 17 18 19 20 

s 

"Q' 

O 

W 

Figure 19 continued. 

______ Y 

11 

I 

S2R7 0703 LT 

n 

25 ?b 27 28 

e. °c 

127 

25 26 27 23 29 

e. °c 
a, gm i kg 

12 13 14 15 16 17 1 

p 

I o 

---- --- --------

------------ ------------ --------------------- 

S2R8 1930 LT 

O 

26 27 28 29 

e. °c 

9" Bm / kg 

13 14 15 16 17 18 19 20 

Figure 19 continued. 

q. gm ~kg 

11 12 13 14 15 16 17 18 19 ,~ 

-~-r--

S2R9 0701 LT 

O 

25 26 27 28 

e, °c 

9.Bn / LB 

14 15 16 17 18 19 20 ~p 

`Q' 

S3R2 1304 LT 

------- - ------------- 

O 

27 29 19 30 31 

e, °c 

128 

26 27 28 29 

e; °c 
Table 22 . 

Lifting Condensation Levels and Mixing Heights 

Profile Tune Cloud Cover LCLP m Mixing Height (h) m LCL~ m 

STA1RS01 1216 LT CLR, HAZE 761 675 875 

STA2RS01 158 LT BKN CU, CB 515 550 562 

STA2RS02 1900 LT SCT CI 1073 880 1125 

STA2RS03 0631 LT BKN ST, CU 570 370 625 

STA2RS04 1902 LT BKN SC 448 400 525 

STA2RS05 0706 LT STC AC 152 400 238 

STA2RS06 1905 LT BKN AC, CS 379 430 438 

STA2R507 0703 LT BKN CU, CB 237 300 300 

STA2RS08 1930 LT SCT CI, CC 477 380 538 

STA2RS09 0701 LT SCT CU, BKN CI 428 420 488 

STA3RS01 1906 LT SCT CU, CI 370 600 438 

STA3RS02 1304 LT 1 BKN CU ~ 670 650 ~ 750 

LCLp is obtained from profile while LCL, was calculated and h is from 8q plot. 

Where: CLR - clear 

SCT - scattered 

BKN - broken 

CU - cumulus 

CB - cumulonimbus 

CI - cirrus 

ST - stratus 

SC - stratocumulus 

AC - altocumulus 

CS - cirrostratus 

CC - cirrocumulus 

129 
RECOMMENDATIONS 
RECOMMENDATIONS 

Ambient levels of S02 and N02 recorded from three remote stations near the Mississippi River 

Delta during the summer of 1994 have been shown to be much lower than the NAAQS. Short-lived 

episodes of higher than average NO,, appear intermittently in the Breton Island record . Since this area 

is subject to EPA Class I PSD regulations, it is recommended that long-term (at least one year) 

continuous monitoring be conducted so that comparisons to PSD increments can be made. The long 

term record will also allow investigation into the frequency and intensity of the high NO,, events . It 

is fiuther suggested that the monitoring network be expanded so that pollutant sources (both on land 

and OCS) may be identified and overwater transport processes better understood . To this end, 

offshore meteorological monitoring (including atmospheric profiles) should be continued. A more 

rigorous program for OCS air quality monitoring and station maintenance should be developed 

(including the acquisition of additional analyzers to minimize downtime). Finally, an additional station 

in the northeast Gulf of Mexico should be established to improve the spatial resolution as described 

above. 

133 
REFERENCES 
REFERENCES 

Boubel, R. W., D. L. Fox, D. B. Turner, and A. C. Stern. 1994. Fundamentals of air pollution. San 

Diego: Academic Press, 574 pp. 

Code of Federal Regulations. 1994 . Title 40, Protection of Environment, Part 58, Appendix B, 

Quality assurance requirements for prevention of significant deterioration (PSD) air 

monitoring . 

Environment Protection Agency. 1979. Quality assurance handbook for air pollution measurement 

systems . Volume II - Ambient air specific methods. EPA-600/4-77-027a. May 1979. 

Available from U.S. Environmental Protection Agency, Environmental Monitoring Systems 

Laboratory (MD-77), Research Triangle Park, NC . 

Garratt, J. R. 1992. The atmospheric boundary layer. Cambridge University Press. 316 pp . 

Holzworth, G. C. 1972. Mixing heights, wind speeds, and potential for urban air pollution 

throughout the contiguous United States . AP-101, Technical Publications Branch, 

Environmental Protection Agency, Research Triangle Park., NC. 118 pp. 

Hsu, S . A. 1995 . Measurements of SOZ concentration and atmospheric structure in Delta and Breton 

Wildlife Refuges. OCS Study MMS 95-0019 . U.S. Dept. of the Interior, Minerals 

Management Service, Gulf of Mexico OCS Region, New Orleans, LA. 74 pp. 

Manahan, S . E. 1993 . Environmental chemistry. Lewis Publishers. 844 pp. 

McIlveen, 7. F. R. 1986. Basic meteorology. Van Nostrand Reinhold (U.K.) Co ., Ltd. 457 pp . 

Spiegel, M. R. 1961 . Schaum's outline of theory and problems of statistics. New York: Schaum 

Publishing Co . 359 pp . 

137 
N F 

p 

The Department of the Interior Mission 

As the Nation's principal conservation agency, the Department of the Interior has responsibility for 

most of our nationally owned public lands and natural resources. This includes fostering sound use 

of our land and water resources; protecting our fish, wildlife, and biological diversity; preserving the 

environmental and cultural values of our national parks and historical places; and providing for the 

enjoyment of life through outdoor recreation. The Department assesses our energy and mineral 

resources and works to ensure that their development is in the best interests of all our people by 

encouraging stewardship and citizen participation in their care. The Department also has a major 

responsibility for American Indian reservation communities and for people who live in island territories 

under U.S. administration . 

The Minerals Management Service Mission 

As a bureau of the Department of the Interior, the Minerals Management Service's (MMS) primary 

responsibilities are to manage the mineral resources located on the Nation's Outer Continental Shelf 

(OCS), collect revenue from the Federal OCS and onshore Federal and Indian lands, and distribute 

those revenues. 

Moreover, in working to meet its responsibilities, the Offshore Minerals Management Program 

administers the OCS competitive leasing program and oversees the safe and environmentally sound 

exploration and production of our Nation's offshore natural gas, oil and other mineral resources. The 

MMS Royalty Management Program meets its responsibilities by ensuring the efficient, timely and 

accurate collection and disbursement of revenue from mineral leasing and production due to Indian 

tribes and allottees, States and the U.S. Treasury . 

The MMS strives to fulfill its responsibilities through the general guiding principles of: (1) being 

responsive to the public's concerns and interests by maintaining a dialogue with all potentially affected 

parties and (2) carrying out its programs with an emphasis on working to enhance the quality of life for 

all Americans by lending MMS assistance and expertise to economic development and environmental 

protection.