Context

We are reviewing the modeling parameters for stacks/release points in the 2014 Inventory. When cleared for launch they will be submitted for modeling to generate statewide pollution estimates and packaged as MNRISKS 2014.

The data

The data below was retrieved from CEDR by joining 2 tables (filtered to the 2014 inventory year):

Shutdown stacks and facilities

A handful of stacks were listed as shutdown but were missing end dates.

Should these stacks be included?

No release points

30 facilities had no release points for 2014.

Should these facilities be included?

TEMPO units

Some stacks assigned incorrect units for modeling parameters. These may have been input wrong through e-services. Many facilities have flow rates in both ACFM and ACFS. A 10 fold increase in flow rate corresponds to 1/6th the final concentration.

Multiple Flow rate units: ACFM and ACFS

Tiny diameters: Default for many imitation stacks set to 0.1 FT (less than 4“)

Flow rates for Dura Supreme Inc

Most flow rates in ACFM

Imitation stacks assigned ACFS units (60X the air flow) and 30X smaller diameters.

This results in an exit velocity 1,800X faster, and is moving faster than shooting bullets and flying chickens.

Reasonable input range

Some stacks were assigned modeling parameters beyond reason. These may have been input through e-services or assigned incorrect units.

Reasonable input range

temp_min temp_max height_min height_max diameter_min diameter_max velocity_min velocity_max
283 1200 1 100 0.1 15 0.001 100

Diameter

Stacks with diameters < 0.1 Feet and flow rates > 1 cubic Meter per second.

Temp

Refrigerated emissions?

Temperature for Imitation SCC xxxxxxxx is 45F.

Funny EPA joke?

Autobody temperatures are assigned human body temperature of 98.6F. “They’re alive!”

Height

Stacks < 1 meter tall or > 100 meters.

Exit velocity

Stacks with ZERO exit velocity.

Stacks with an exit velocity < 0.001 or greater than 100 m/s.

Missing values

Some stacks are missing all or several model parameters.

Should stacks with missing parameters be modeled?

What is different about the stacks without parameters?

All parameters missing

Height

Not including stacks with all parameters missing.

Flow rate

Diameter

Temp