PVIScreen is a model for assessing impacts from petroleum vapors on residences. PVIScreen was designed for automatic uncertainty analysis using Monte Carlo simulation. The main result from the model is a probabiliy curve for indoor air concentration for each simulated chemical. Both cancer and non-cancer risk levels are indicated on the probability curves.
PVIScreen is based on the BioVapor model (Devaull, 2007; API, 2010). PVIScreen extends the capabilities of BioVapor by including automatic uncertainty analysis, flexible unit selection, and direct inclusion of liquid gasoline (NAPL). Major assumptions of the model include:
The results in this report were generated from: GroundWaterExampleMW-3.pvi.
The result file is: GroundWaterExampleMW-3 2021-Apr-14-18h-57m-36.0s.PVIScreen.Results.csv.
This file is: GroundWaterExampleMW-3 2021-Apr-14-18h-57m-36.0s.PVIScreen.Results.csv.htm.
All of these are located in directory: C:\Users\Jim.000\eclipse-workspace\PVIScreen-9-5-2018\projects\examples\.
The depths of the foundation, water table, historic water table, top of contamination are shown in Figure 1. The depth of the foundation is 0. ft, and the depth to the water table is 9.780 ft. The depth to the historic water table is 19.84 ft.
The distance between the bottom of the foundation and the sample that defines the contamination is -9.780 ft. The depth of sample is 9.780 ft.Figure 1 Site Schematic.
The source of contamination is defined by: 8 chemicals with water phase data.
Table 1 Source Definition. | ||
---|---|---|
Name | Source Data | Concentration |
benzene | WaterPhaseConcentration | 39.40 mg/L |
toluene | WaterPhaseConcentration | 49.00 mg/L |
ethylbenzene | WaterPhaseConcentration | 3.260 mg/L |
xylenes | WaterPhaseConcentration | 17.20 mg/L |
Naphthalene | WaterPhaseConcentration | 0.6880 mg/L |
MTBE | WaterPhaseConcentration | 0.1000 mg/L |
TPH-GRO | WaterPhaseConcentration | 118.0 mg/L |
TPH-DRO | WaterPhaseConcentration | 0.9396 mg/L |
Modeled indoor air concentrations are compared to screening the following screening levels.
Table 2 Screening Level Results. | ||
---|---|---|
Name | Screening Level | % Simulations Above Screening Level |
TPH-GRO | 307.0 | 69.43 |
benzene | 0.5000 | 66.74 |
TPH-DRO | 307.0 | 26.06 |
toluene | 7154.0 | 0. |
ethylbenzene | 1482.0 | 0. |
xylenes | 148.0 | 0. |
Naphthalene | 4.390 | 0. |
MTBE | 4395.0 | 0. |
Input parameters can be chosen to vary according to a statistical distribution or be set as constants. Tables separately give the values of the variable (Table 4) and constant (Table 5) parameters.
Table 4 Variable parameters from file: GroundWaterExampleMW-3.pvi. | |||||
---|---|---|---|---|---|
Group | Parameter | Distribution Type | Value | Unit | Frequency |
Building | FoundationThickness | Variable | 6.0 | in | 0.0 |
Building | FoundationThickness | Variable | 8.0 | in | 1.0 |
Building | CrackWidth | Variable | 0.5 | mm | 0.0 |
Building | CrackWidth | Variable | 5.0 | mm | 1.0 |
Building | AirExchangeRate | Variable | 0.5 | 1/hr | 0.0 |
Building | AirExchangeRate | Variable | 1.5 | 1/hr | 1.0 |
Vadose Zone | MoistureContent | Variable | 0.049 | dimensionless | 0.0 |
Vadose Zone | MoistureContent | Variable | 0.2127 | dimensionless | 1.0 |
Vadose Zone | Porosity | Variable | 0.29 | dimensionless | 0.0 |
Vadose Zone | Porosity | Variable | 0.484 | dimensionless | 1.0 |
Vadose Zone | FractionOrganicCarbon | Variable | 7.5E-4 | dimensionless | 0.0 |
Vadose Zone | FractionOrganicCarbon | Variable | 0.00125 | dimensionless | 1.0 |
Vadose Zone | SoilTemperature | Variable | 11.25 | C | 0.0 |
Vadose Zone | SoilTemperature | Variable | 18.75 | C | 1.0 |
Table 5 Constant parameters (and effectively constant parameters) from file: GroundWaterExampleMW-3.pvi. | ||||
---|---|---|---|---|
Group | Parameter | Distribution Type | Value | Unit |
Building | Width | Constant | 50.0 | feet |
Building | Length | Constant | 50.0 | feet |
Building | CeilingHeight | Constant | 9.0 | ft |
Building | FoundationDepthBelowGrade | Constant | 0.0 | in |
Vadose Zone | DepthToSample | Constant | 9.78 | ft |
Vadose Zone | DepthToWater | Constant | 9.78 | ft |
Vadose Zone | DepthToHistoricWaterTable | Constant | 6.048 | m |
Vadose Zone | DepthToBottom | Constant | 20.0 | ft |
Chemical | benzene | Constant | 39.4 | mg/l |
Chemical | toluene | Constant | 49.0 | mg/l |
Chemical | ethylbenzene | Constant | 3.26 | mg/l |
Chemical | xylenes | Constant | 17.2 | mg/l |
Chemical | naphthalene | Constant | 0.688 | mg/l |
Chemical | MTBE | Constant | 0.1 | mg/l |
Chemical | TPH-GRO | Constant | 118.0 | mg/l |
Chemical | TPH-DRO | Constant | 0.9396 | mg/l |
ScreeningLevel | TPH-GRO | Effectively Constant (*) | 307.0 | ug/m3 |
Building | Qsoil | Effectively Constant (*) | 5.5 | L/m |
Oxygen | DiffusionInAir | Constant | 0.175 | cm2/s |
Oxygen | DiffusionInWater | Constant | 1.7E-5 | cm2/s |
Oxygen | SurfaceConcentration | Constant | 289000.0 | mg/m3 |
Oxygen | MinimumBiodegradationConcentration | Constant | 13800.0 | mg/m3 |
(*) Parameter is effectively constant because input was declared variable, but the two or more input values were the same. |
Table 6 Variable parameters from file: GroundWaterExampleMW-3.pvi. | ||||||
---|---|---|---|---|---|---|
Group | InputType | Distribution Type | Chemical | Value | Unit | Frequency |
Chemical | WaterPhaseConcentration | Constant | benzene | 39.4 | mg/l | 1.0 |
Chemical | WaterPhaseConcentration | Constant | toluene | 49.0 | mg/l | 1.0 |
Chemical | WaterPhaseConcentration | Constant | ethylbenzene | 3.26 | mg/l | 1.0 |
Chemical | WaterPhaseConcentration | Constant | xylenes | 17.2 | mg/l | 1.0 |
Chemical | WaterPhaseConcentration | Constant | naphthalene | 0.688 | mg/l | 1.0 |
Chemical | WaterPhaseConcentration | Constant | MTBE | 0.1 | mg/l | 1.0 |
Chemical | WaterPhaseConcentration | Constant | TPH-GRO | 118.0 | mg/l | 1.0 |
Chemical | WaterPhaseConcentration | Constant | TPH-DRO | 0.9396 | mg/l | 1.0 |
Chemical parameters are found in the systemData file 02ChemicalProperties.cvs and Table (7)
Table 7 Chemical parameters from system data file 01ChemicalProperties.csv. | |||||||||
---|---|---|---|---|---|---|---|---|---|
Chemical | Distribution | Molecular Weight | Solubility | Density | Koc | Phi | Diffusion in Air | Diffusion in Water | First Order Rate Constant |
benzene | 78100.0 | 1.780 | 876.5 | 0.08120 | 0.3250 | 0.08800 | 1.01E-5 | 2.194E-4 | |
toluene | 92100.0 | 0.5150 | 866.9 | 0.2340 | 0.3200 | 0.08700 | 8.6E-6 | 2.194E-4 | |
ethylbenzene | 106200.0 | 0.1520 | 867.0 | 0.5370 | 0.3160 | 0.07500 | 7.8E-6 | 2.194E-4 | |
xylenes | 106200.0 | 0.1980 | 875.2 | 0.5860 | 0.3160 | 0.07100 | 9.34E-6 | 2.194E-4 | |
Naphthalene | 128000.0 | 0.03100 | 1030.0 | 0.8440 | 0.3330 | 0.05900 | 7.5E-6 | 3.333E-5 | |
MTBE | 88100.0 | 42.00 | 740.0 | 0.01410 | 0.3670 | 0.07920 | 9.41E-6 | 7.222E-7 | |
TPH-GRO | 93000.0 | 0.008410 | 871.0 | 10.00 | 0.3060 | 0.1000 | 1.0E-5 | 0.01972 | |
TPH-DRO | 142000.0 | 5.3E-5 | 693.2 | 10.00 | 0.2860 | 0.1000 | 1.0E-5 | 0.04444 |