Annual Mean Measurements and MNRiskS Annual Modeled Concentrations were compared using:

-Scatterplots of air toxics, criteria pollutants and single pollutants
-Model Monitor Statistics

-Measured Data are Collected from the Air Data Folder:
Folder location for Air Data

Measured Data are Summarized and assigned an AQS and an MPCA Site ID:

-Arithmetic means were calculated for 2011 by parameter, and site for criteria pollutants
-MLE means were calculated for air toxics for 2011 by parameter and site
Prepared and saved here for monitor measurements and the MNRiskS result at the closest receptor

MNRiskS receptors were assigned to ambient air monitor IDs


-MNRiskS receptors within a 5km buffer of an ambient monitor
-The closest MNRiskS receptors to each ambient air monitor were also identified. This is the map project used to identify nearest receptors and receptors within 5km of an ambient air monitor
-There was only one site with a high enough detected level of chromium to provide an annual mean estate. This was from a special monitoring project that was specific to one facility (Grede Foundry). DCI, a stainless steel manufacturer was found to be the source of the high measured chromium. Due to the very specific nature of this monitoring effort, these results were not included in the model-monitor comparison.

MNRiskS results were pulled and pared down to those closest to monitors and within 5km


-MnRiskS data for all monitored pollutants were pulled from the FTP site, and converted from an .rsk to an .rds file using this script.
This script creates a dataframe from the raw MNRiskS results in the .rsk format and puts columns names on the dataframe, saves as an .rds

-MNRiskS receptors were joined to buffer and closest receptors and saved as a csv file.
This script pares down MNRiskS results to those at closest receptors and receptors within 5km buffers

-MNRiskS results are then paired with measured results prior to making plots and calculating model monitor statistics.
This script pares down MNRiskS results to those at closest receptors and receptors within 5km buffers

-The result of the work in this file was done using two csv files.
Paired measurements, MNRiskS values, and site IDs.
Paired measurements, MNRiskS values, receptors, and site IDs.

Single Pollutant Scatterplots


-The smoothed line is the linear regression line
-The dotted line is the slope = 1, intercept = 0 abline
-Click the links to open the pds of these plots
-Select the back arrow to return to the html

Prepared and saved here for monitor measurements and the MNRiskS result at the closest receptor

Prepared and saved here for monitor measurements and the mean MNRiskS results for receptors within 5 km (of the monitor)

Multiple Pollutant Scatterplots (Air Toxics)


Multiple Pollutant Scatterplots (Criteria Pollutants)


Pollutant Comparisons (Averaged Receptors Results within 5km buffer of Ambient Monitor)


Pollutant Comparisons (Closest Receptors Results to Ambient Monitor)


Model Monitor Statistical Values

The model-monitor statistics were calculated in R using the openair package and the modStats command.
modStats(mydata, mod = “mod”, obs = “obs”, statistic = c(“n”, “FAC2”,
“MB”, “MGE”, “NMB”, “NMGE”, “RMSE”, “r”, “COE”, “IOA”), type = “default”,
rank.name = NULL, …)

All of the specific model monitor comparison statistics are described at this link: (http://www.inside-r.org/packages/cran/openair/docs/modStats) ######The Model-monitor tables are in descending order by the fraction of site-model matches within a factor of 2. Therefore, the pollutants that are at the top of these tables are the best predicted pollutants.

Model Monitor Statistical Values for Closest Receptors

##                 substance Counts   tau   sl FAC2     COE   IOA FrxBias
## 8            Formaldehyde     12  0.61 0.01 1.00   -0.23  0.39   -1.72
## 9    Carbon Tetrachloride     12 -0.48 0.03 1.00  -15.99 -0.88    9.26
## 13          Chloromethane     12  0.33 0.15 1.00   -0.30  0.35    3.46
## 15           Acetaldehyde     12  0.48 0.03 1.00   -1.86 -0.30   33.01
## 1                   PM2.5     18  0.62 0.00 0.78   -2.19 -0.37   49.46
## 27        NitrogenDioxide      3  0.33 1.00 0.67   -2.38 -0.41   58.05
## 2           1,3-Butadiene     11  0.60 0.01 0.64   -2.70 -0.46   51.61
## 21      Trichloroethylene      5  0.60 0.22 0.60   -7.44 -0.76   26.52
## 26         CarbonMonoxide      5  0.40 0.46 0.60   -0.39  0.30   24.55
## 12                Benzene     12  0.82 0.00 0.58   -4.92 -0.66   69.02
## 22                   Lead      7  0.33 0.37 0.57   -3.21 -0.52   82.72
## 20                   PM10      8 -0.04 1.00 0.50   -6.24 -0.72  101.08
## 11             Chloroform     10  0.51 0.05 0.40   -2.46 -0.42  -47.33
## 5                N-Hexane     12  0.48 0.03 0.33   -5.50 -0.69  111.57
## 23              Manganese      9  0.00 1.00 0.33   -2.16 -0.37  -35.05
## 18    Methyl Ethyl Ketone     12  0.30 0.19 0.25   -4.44 -0.63  -75.05
## 25                   Zinc      8  0.14 0.71 0.25   -0.83  0.08 -103.70
## 14          SulfurDioxide      5  0.00 1.00 0.20   -1.60 -0.23   63.72
## 6             Cyclohexane     11  0.20 0.44 0.09   -2.03 -0.34 -113.56
## 4                 Toluene     12  0.73 0.00 0.08  -18.17 -0.90  152.86
## 3           Vinyl Acetate     12  0.06 0.84 0.00   -8.87 -0.80 -198.27
## 7              M/P Xylene      7  0.81 0.02 0.00  -32.36 -0.94  131.58
## 10                Acetone     12  0.61 0.01 0.00   -9.38 -0.81 -168.33
## 16        Dichloromethane     12  0.67 0.00 0.00   -3.73 -0.58 -125.67
## 17       Carbon Disulfide      8 -0.21 0.54 0.00    0.29  0.65 -188.04
## 19 1,2,4-Trimethylbenzene      7  0.05 1.00 0.00  -12.90 -0.86  -88.00
## 24                 Barium      7 -0.14 0.76 0.00   -6.82 -0.74 -194.16
## 28                 Cobalt      1    NA   NA 0.00    -Inf -1.00 -176.95
## 29    Tetrachloroethylene      2    NA   NA 0.00   -9.47 -0.81  -79.97
## 30                 Nickel      1    NA   NA 0.00    -Inf -1.00 -149.60
## 31      Methyl Chloroform      1    NA   NA 0.00    -Inf -1.00  148.33
## 32           Ethylbenzene      2    NA   NA 0.00 -436.20 -1.00   89.68
## 33               Chromium      1    NA   NA 0.00    -Inf -1.00 -156.50

Model Monitor Statistical Values for Average MNRiskS Results for Receptors within 5km of a Monitor

##                 substance Counts   tau   sl FAC2     COE   IOA FrxBias
## 9            Formaldehyde     16  0.32 0.10 1.00   -0.35  0.32  -16.36
## 10   Carbon Tetrachloride     16 -0.27 0.16 1.00   -9.18 -0.80    8.93
## 13          Chloromethane     15  0.51 0.01 1.00   -0.32  0.34    3.49
## 15           Acetaldehyde     16  0.32 0.10 1.00   -1.01  0.00   24.77
## 19          1,3-Butadiene     15  0.66 0.00 1.00   -0.55  0.23   15.15
## 27      Trichloroethylene      5  0.80 0.09 1.00   -5.51 -0.69   36.52
## 4                   PM2.5     22  0.61 0.00 0.77   -1.92 -0.32   44.84
## 12                Benzene     16  0.52 0.01 0.75   -2.02 -0.34   37.58
## 2                    PM10      6 -0.20 0.71 0.67   -1.27 -0.12   16.24
## 25           Ethylbenzene      3 -1.00 1.00 0.67  -12.80 -0.86   52.03
## 22                   Lead      8  0.07 0.90 0.50    0.25  0.63 -110.46
## 5         NitrogenDioxide      3 -0.33 1.00 0.33   -3.03 -0.50   65.65
## 1           SulfurDioxide      7 -0.20 0.65 0.29   -1.31 -0.14   80.18
## 8                N-Hexane     14  0.31 0.14 0.29   -2.51 -0.43   83.71
## 14              Manganese     11  0.22 0.39 0.27   -0.18  0.41  -85.19
## 21             Chloroform     13  0.47 0.03 0.23   -2.86 -0.48  -75.10
## 26             M/P Xylene      9  0.39 0.18 0.22  -12.71 -0.85  103.40
## 18    Methyl Ethyl Ketone     14  0.29 0.17 0.21   -5.22 -0.68  -93.96
## 24                   Zinc     10  0.13 0.65 0.20   -1.00  0.00  -64.18
## 7                 Toluene     16  0.39 0.04 0.19   -8.46 -0.79  132.47
## 3          CarbonMonoxide      6 -0.20 0.71 0.17   -0.42  0.29 -156.48
## 20            Cyclohexane     15  0.03 0.92 0.07   -1.30 -0.13 -159.71
## 6           Vinyl Acetate     16  0.24 0.22 0.00   -6.97 -0.75 -198.00
## 11                Acetone     15  0.51 0.01 0.00   -8.97 -0.80 -168.33
## 16        Dichloromethane     16  0.54 0.00 0.00   -4.28 -0.62 -133.56
## 17       Carbon Disulfide     12  0.12 0.63 0.00    0.23  0.62 -186.50
## 23                 Barium      9 -0.48 0.09 0.00   -4.84 -0.66 -161.99
## 28 1,2,4-Trimethylbenzene      8  0.36 0.27 0.00   -9.74 -0.81 -155.42
## 29    Tetrachloroethylene      2    NA   NA 0.00  -10.74 -0.83  -94.28
## 30      Methyl Chloroform      2    NA   NA 0.00 -102.92 -0.98  128.94

Notes and Preliminary Conclusions


-The following pollutants had more than half of the model - monitor matches at or near within 2 times of eachother: PM2.5, PM10, benzene, 1,3 butadiene, trichloroethylene, acetaldehyde, and formaldehyde.
-Some of the agency priority pollutants fall into this category of pollutants with more than half of the model - monitor matches at or near within 2 times of eachother.
-The following pollutants need further investiation, as their model-monitor matches were fairly far outside of a factor of two agreement: sulfur dioxide, vinyl acetate, carbon monoxide, carbon disulfide, barium, cyclohexane, acetone, 1,2,4 trimethylbenzene, toluene, xylenes, methyl chloroform, manganese.
-This model does well for the fraction of paired values within a factor of 2. The paired measured-modeled values do less when compared to a 1:1 line.
-In general, the model predicts more spatial variability than is measured.
-The number of model - monitor match pairs that are within a factor of 2 of eachother improved over the 2008 and 2005 version of MNRiskS.