Tracer Data
Meteorological Data
Model Evaluation




EPRI Kincaid Field Study


SF6 sampling is available for two time periods: April 20, 1980 through August 29, 1980, and May 9, 1981 through June 1, 1981. SO2 sampling is available from April 3, 1980 through June 17, 1981.


There were three "Intensives", when monitoring was enhanced and more detailed sampling was conducted. Intensive measurements were conducted for 150 hours over three 3-week periods during the spring and summer of 1980 and spring of 1981. The three "Intensives" were:


April 21, 1980 - May 11, 1980;

July 7, 1980 - August 3, 1980, and

May 4, 1981 - June 7, 1981.



The Kincaid plant is surrounded by generally flat farmlands, and thus we have good reason to believe in horizontal homogeneity in meteorological conditions in the near-vicinity of the plant. The surface roughness varies from 7cm to 15cm, depending on time of year and wind direction. The coordinates of the stack are:

UTM-E (km):             285.597

UTM-N (km):            4385.088

Latitude (deg):           39.5906 N

Longitude (deg):        89.4967 W



Hourly Sulphur hexafluoride (SF6).

Hourly Sulfur Dioxide (SO2)

5-Minute Sulfur Dioxide (SO2)



A 10-second polling rate was made of stack gas emissions, plus stack temperature at the 137-meter (450-foot) level of the 187-meter stack. As a backup procedure, the SO2 emission rate, exit velocity, and temperature were also calculated from plant operating information, daily fuel consumption data, hourly electrical load data, and daily coal analyses. All 10-second data were converted and packaged as 5-minute averages, and these 5-minute averages were then used to construct 1-hour values. Because the stack gas velocity probe was, not operational, one-hour average values of stack velocity were calculated from plant operating data.



SF6 Tracer Monitoring Network

A network of approximately 1500 potential tracer sampling locations was used at the Kincaid site. The network design consisted of concentric circles at average radial distances of 0.5, 1, 2, 3, 5, 7, 10, 15, 20, 30, 40, and 50 km from the power plant. Using the existing roadway network, the downwind distance of the samplers assigned to an arc varied as much as 20 percent of the mean distance. The monitors on the arcs were spaced at azimuthal intervals ranging from 2o to 8o. Pulsed pump grab samplers, with a 2-second pulse every 20 seconds, were used to produce a 1-hour integrated sample.


Tracer tests generally lasted six to nine hours. During this period, SF6 tracer gas was injected continuously into the ductwork of the 187-m stack. During each test approximately 200 sampling sites located on five to seven of the arcs in a sector ranging from 90o to 180o of arc, were operating. The sampling array was chosen on the basis of the expected meteorological conditions and remained fixed during any given test period.


SF6 tracer data are available for two collection periods:

April 20 1980 through August 29 1980, and

May 9 1981 through June 1 1981.


Hourly SO2 Monitoring Network

There were 30 receptors, with most of the receptors in the range from 5km to 15km from the stack. The receptors were placed in a 90o sector from NW to NE of the stack. SO2 sampling is available from April 3, 1980 through June 17, 1981 [see Fig 4-2 and Fig 4-3, Bowne and Londergan ( 1983.].


5-Minute SO2 Monitoring Network

I have been provided copies of the data archive files that were constructed by SAI. Each archive file provides the data available for a one-week period. There are sixty-one archive files. I have not processed all of the available data for distribution, but I have created a listing of what I hope will be at least initially useful.


For each 5-min sampling period, I have provided a listing of 25 meteorological variables, the SO2 emission rate, a factor for converting SO2 in PPB to micrograms/m^3, and such 5-min SO2 concentrations that are available.


The number of 5-min SO2 receptors varies from one week to the next, with a minimum of zero (0) to a maximum of thirty-two (32). KincaidArchiveFileSummary.txt [4KB] summarizes the sampling periods covered in the 61 archive files, and Kincaid5-minVariablesSummary.txt [2KB] summarizes the 5-min variables listed for each 5-min sampling period.



The location of the 'Central Station' where most of the meteorological observations were performed, including the 100-m and 10-m meteorological towers, was: Easting 286.30 km Northing 4385.169 km Elevation 183 m. This places the site at 645 m East of the Kincaid stack. Routine weather observations were also obtained at this site. The site was situated in fallow fields away from major obstructions.


1. From the data collected onsite, I am distributing:

wind direction and wind speed from 10-, 30-m 50-, and 100-m

Temperature from 10-, 50-, and 100-m.

Dewpoint from 100m.

2-10m Delta-T

Atmospheric pressure,

Net, Solar and Total Sky Radiation

Acoustic Sounder Mixing Heights


2. From analyses conducted by the original EPRI investigators, I am distributing:

Monin-Obukhov length for dry and moist conditions

Surface friction velocity for dry and moist conditions

Mixing height estimates for dry and moist conditions

Pasquill Stability Category

Surface roughness length, albedo and bowen ratio as a function of wind sector and month


3. Rawindsonde observations from Peoria, IL.


4. Standard surface weather observations from eight (8) NWS stations.



The primary purpose of the EPRI Plume Model Validation and Development Project was to generate an extensive base of air quality and meteorological data. These data were to be used toward the first two objectives of the overall PMV&D Project:


1. Establish, by statistically rigorous procedures, the accuracy and uncertainty of ground-level concentrations predicted by existing plume models.


2. Assess model performance over a range of meteorological topographical and source conditions at a given site and determine the transferability of plume models from one site to another.


The field study site at the Kincaid Power Plant was chosen because it was isolated, so there would be no confusion as to where the tracer or SO2 was coming from, and because the terrain was relatively flat, and thus was free of terrain induced meteorological transport effects.


As part of this effort, the data collected at Kincaid was divided into two independent data sets so that the data used to evaluate an air quality transport and diffusion model would be independent of that used to develop a model. Half of the data set was used for a model development program sponsored by EPRI and was called the Developmental data set. The other half of the data set was used to evaluate the Hybrid Plume Dispersion Model (HPDM), Hanna and Paine (1989), and was called the Evaluation data set.


In 1991, a European initiative was launched for increased cooperation and standardization of atmospheric dispersion models for regulatory purposes. Conferences are held approximately every 18 months. As part of this initiative a Model Validation Kit [] was developed starting in 1993. Currently, the kit contains four field data sets as well as software for model evaluation. In collaboration with the principal investigators of the EPRI Plume Model Validation and Development Project, the Developmental data set was incorporated into the Model Validation Kit for distribution and use. Up until this time, the other half of the data, the Evaluation Data Set, has not been distributed.


In this release of the data, the Developmental and Evaluation Data Sets have been merged together, which essentially doubles the amount of data available for analysis.


The hourly SO2 data are being included so that research investigation can assess jointly the SF6 and SO2 sampling results.



Informational Files


KincaidDiscussion.pdf: Provides an overview of the data being made available. [42KB]


Logic_Behind_Kincaid_SF6-Arcs.pdf: This file describes why I was unsuccessful in combining the Developmental and Evaluation data sets and retain the subjective receptor placements used in the original investigations. I developed and used an objective scheme to place receptors along arcs that is nearly the same as that used in the original investigations. I also developed and used an objective scheme for assessing the quality of the SF6 for determination of the maximum concentration along an arc. [56.6MB]


UA5600format.txt: Explains Upper Air 5600 format [1.9KB]


KB50andKB51_SF6Data_Format.txt: Original archive format for SF6 concentration data values. [3KB]


KB52andKB53_SO2Data_Format.txt: Original archive format for SO2 concentration data values. [2KB]


Kincaid-SF6-SamplingSummary.txt: In the original investigations, the data was divided into two (2) data sets; one for model development and one for model evaluation. This file list in a table format the days included in Developmental and Evaluation data sets. [2.98KB]


Kincaid_Suspect_SF6_Arc-Max_Values.pdf: I developed an objective scheme for assessing the quality of the sampling along the SF6 arcs. This file discusses the 13 cases where my assessment scheme determined the maximum SF6 concentration might be suspect. [89.3KB]


Kincaid-KB-47(SO2-Receptor-Coordinates)11172011.txt: This file list the coordinates for the 30 SO2 receptors having hourly SO2 values. [2.5KB]


Meteorological Data Files


KincaidNearSurfaceMetData11022011.txt: Hourly near-surface meteorological observations collected at the Kincaid plant site. [1.54MB]


KincaidTowerMetData09222011.txt: Hourly meteorological observations collected from the 100-m tower located near the Kincaid plant site. [894KB]


Kincaid-KB-89(NWS-UA5600).txt: US National Weather Service Upper Air data in 5600 format. Data begin February 24, 1980 and end June 30, 1981. Upper air balloon was released from Peoria, IL. [600KB]



                                                      NWS Hourly Surface Weather Data

                                                  1980               1981            Format                                   W94846.h80  W94846.h81  W94846.txt [407KB]                            W14923.h80  W14923.h81  W14923.txt [407KB]                             W14842.h80  W14842.h81  W14842.txt [406KB]                         W94822.h80  W94822.h81  W94822.txt [460KB]                       W93822.h80  W93822.h81  W93822.txt [455KB]                            W13994.h80  W13994.h81  W13994.txt [404KB]                        W93817.h80  W93817.h81  W93817.txt [399KB]                     W93819.h80  W93819.h81  W93819.txt [408KB]


The hourly data for the stations listed above was obtained from: The meteorological data files available at this site contain measurements taken at 237 weather stations located throughout the United States for a period extending from 1961 to 1990. Exact collection dates vary by weather station. These data files are compatible with the EXAMS, PRZM, and EXPRESS systems distributed through the EPA Center for Exposure Assessment Modeling (CEAM).


SF6 Tracer Data Files


KincadSF611052011.txt: Detailed listing of SF6 concentration values at each receptor along an arc. There were 12 receptor arcs, but not all were active during each hour of sampling. In this file, the data values are listed separately for each receptor arc that was active during each hour. [6.6MB]


KincaidSF6Max11052011.txt: A listing of the maximum SF6 concentration seen along each arc and the objective ‘judgment’ code of whether the maximum is likely well characterized by the sampling available. I have also included the QC index for the Development Data distributed in the Harmonization Model Validation Kit, but since I used a different scheme for assigning receptors to arcs, these QC index values are only useful for informational purposes. To see where differences occur using my receptor placement and that used by the EPRI investigators, compare this file with SF6_KIN.dat, distributed in the Harmonization Model Validation Kit. [256KB]


KincaidSF6-Arcs.pdf: This file displays the SF6 concentration values in a fashion similar to that employed by the original investigators. [388KB]


Kincaid-KB-50(SF6-Developmental).txt: SF6 data for the Developmental data set, in the original format of the Kincaid data archive. [1.26MB]


Kincaid-KB-51(SF6-Evaluation).txt: SF6 data for the Evaluation data set, in the original format of the Kincaid data archive. [910KB]


KincaidCombinedSF6-50and_51.txt: A spliced together version of the SF6 data for the Developmental and Evaluation data sets, in the original format of the Kincaid data archive. [1.85MB]


Hourly SO2 Data Files


KincadHOURLYSO211022011.txt: Listing of SO2 concentration values at each receptor for each hour. There were 30 receptors. [9.69MB]


Kincaid-KB-52(Hrly-SO2-Developmental).txt: Hourly SO2 data for the Developmental data set, in the original format of the Kincaid data archive. [422KB]


Kincaid-KB-53(Hrly-SO2-Evaluation).txt: Hourly SO2 data for the Evaluation data set, in the original format of the Kincaid data archive. [390KB]


KincaidCombinedSO2-52and 53.txt: Spliced together version of the hourly SO2 data for the Developmental and Evaluation data sets, in the original format of the Kincaid data archive. [811KB]


5-Minute Meteorological and SO2 Data


KincaidList5minData.txt [54MB]:For each 5-min sampling period, I have provided a listing of 25 meteorological variables, the SO2 emission rate, a factor for converting SO2 in PPB to micrograms/m^3, and such 5-min SO2 concentrations that are available.

KincaidRead5minData.txt [5KB]: A FORTRAN file that is capable of reading file List5minData.txt.


Bowne, N.E., and R.J. Londergan. 1983. EPRI Plume Model Validation and Development Project and Experimental Design-Plains Site. EPRI Report No. EA-3075. Prepared by TRC Environmental Consultants, Inc., East Hartford, Conn. Palo Alto, Calif.: Electric Power Research Institute.


Hanna, S.R., and Paine, R.J., (1989): Hybrid plume dispersion model (HPDM) development and evaluation. J. Of Applied Meteorology. (28):206-224.


I have reformated the data that was provided to me. If there are errors in the data I have provided, most likely they are a result of my efforts to format and organize the data for distribution. No fault should be placed on the kind people who provided me with their data files.

Joseph C. Chang provided me with all of his Kincaid data files, which we have come to understand were likely created by someone working for SAI, many years ago. Gary Moore provided me with all of his Kincaid data files, which are the sixty-one archive one-week files I discuss.

Through a series of Emails, Norman Bowne, Roger Brode, Steve Hanna, Jayant Hardikar, Russ Lee, Douglas R. Murray, Helge Olesen, Bob Paine, James Paumier, Don Shearer, and Dave Strimaitis have all tried to help me decipher the avaliable data files. As you can see, I need lots of help, and I am honored that so many have offered their help.