Facility Name:Neil Simpson II
Facility Identifier:
Facility Reporting Year:2020
Facility Location:
Address: 13151 HIGHWAY 51
City: GILLETTE
State: WY
Postal Code: 82718

Facility Site Details:
CO2 equivalent emissions from facility subparts C-II, SS, and TT (metric tons):875,763.4
CO2 equivalent emissions from supplier subparts LL-QQ (metric tons):
Biogenic CO2 emissions from facility subparts C-II, SS, and TT (metric tons):0
Cogeneration Unit Emissions Indicator:N
GHG Report Start Date:2020-01-01
GHG Report End Date:2020-12-31
Description of Changes to Calculation Methodology:
Plant Code Indicator:Y
Primary NAICS Code:221112
Second Primary NAICS Code:

Parent Company Details:
Parent Company Name:BLACK HILLS CORP
Address:7001 Rushmore Road, Rapid City,  SD 57702
Percent Ownership Interest:100

Subpart C: General Stationary Fuel Combustion

Gas Information Details

Gas NameCarbon Dioxide
Gas Quantity360.1 (Metric Tons)
Own Result?

Gas NameBiogenic Carbon dioxide
Gas Quantity0 (Metric Tons)
Own Result?

Gas NameMethane
Gas Quantity0.01 (Metric Tons)
Own Result?

Gas NameNitrous Oxide
Gas Quantity0.001 (Metric Tons)
Own Result?

Unit Details:
Unit Name : GP-NS-Hanover/exterran Heaters
Unit Type : PRH (Process Heater)
Unit Description :
Individual Unit Details:
Use Ivt Indicator: Y
Maximum Rated Heat Input Capacity: 3.6 (mmBtu/hr)

Emission Details:
Annual CO2 mass emissions from sorbent: 0 (Metric Tons)
Annual Biogenic CO2 Emissions: 0 (metric tons)

Tier Fuel Details:
Fuel : Natural Gas (Weighted U.S. Average)
Tier Name : Tier 2 (Equation C-2a)
Tier Methodology Start Date : 2020-01-01
Tier Methodology End Date : 2020-12-31
Frequency of HHV determinations : Monthly

Tier 2 Monthly HHV Details :
JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember
N N N N N N N N N N N N

Fuel Emission Details :
Total CO2 emissionsTotal CH4 emissionsTotal N2O emissionsTotal CH4 emissions CO2eTotal N2O emissions CO2e
339.7 (Metric Tons) 0.01 (Metric Tons) 0.001 (Metric Tons) 0.2 (Metric Tons) 0.2 (Metric Tons)


Unit Name : NS-CT1-Heater
Unit Type : PRH (Process Heater)
Unit Description :
Individual Unit Details:
Use Ivt Indicator: Y
Maximum Rated Heat Input Capacity: 17.5 (mmBtu/hr)

Emission Details:
Annual CO2 mass emissions from sorbent: 0 (Metric Tons)
Annual Biogenic CO2 Emissions: 0 (metric tons)

Tier Fuel Details:
Fuel : Natural Gas (Weighted U.S. Average)
Tier Name : Tier 2 (Equation C-2a)
Tier Methodology Start Date : 2020-01-01
Tier Methodology End Date : 2020-12-31
Frequency of HHV determinations : Monthly

Tier 2 Monthly HHV Details :
JanuaryFebruaryMarchAprilMayJuneJulyAugustSeptemberOctoberNovemberDecember
N N N N N N N N N N N N

Fuel Emission Details :
Total CO2 emissionsTotal CH4 emissionsTotal N2O emissionsTotal CH4 emissions CO2eTotal N2O emissions CO2e
20.4 (Metric Tons) 0.00 (Metric Tons) 0.000 (Metric Tons) 0 (Metric Tons) 0 (Metric Tons)



Subpart D: Electricity Generation

Gas Information Details

Gas NameCarbon Dioxide
Gas Quantity870,975.8 (Metric Tons)
Own Result?

Gas NameBiogenic Carbon dioxide
Gas Quantity0 (Metric Tons)
Own Result?

Gas NameMethane
Gas Quantity9.47 (Metric Tons)
Own Result?

Gas NameNitrous Oxide
Gas Quantity14.061 (Metric Tons)
Own Result?

Unit Details:

Unit Name : CT1
Unit Type : Electricity Generator
Unit Description :
Plant Code : 7504 (numeric, maximum of 6 digits)
Part 75 Methodology : Appendix G, Equation G-4
Methodology Start Date: 2000-09-12
Methodology End Date: 2020-12-31
Acid Rain Program Indicator: Y

Emission Details:
Annual CO2 Emissions Including Biomass (metric tons): 39165.7
Annual CO2 Emissions Including Biomass (short tons): 43172.3
Annual CO2 Emissions from Biomass (metric tons): 0

Appendix G Equation G4:
Operating Hours Fuel Flow Rate: 0
Operating Hours HHV Substitution: 0

Electricity Fuel Details:
Fuel type: Natural Gas (Weighted U.S. Average)
Annual heat input:  726466 (mmBtu)
CH4 Emissions CO2 Equivalent:  18.2  (Metric Tons)
N2O Emissions CO2 Equivalent:  21.6  (Metric Tons)


Unit Name : 001
Unit Type : Electricity Generator
Unit Description :
Plant Code : 7504 (numeric, maximum of 6 digits)
Part 75 Methodology : CEMS
Methodology Start Date: 1995-09-11
Methodology End Date: 2020-12-31
Acid Rain Program Indicator: Y

Emission Details:
Annual CO2 Emissions Including Biomass (metric tons): 831810.1
Annual CO2 Emissions Including Biomass (short tons): 916904.3
Annual CO2 Emissions from Biomass (metric tons): 0

CEMS Details:
Operating Hours CO2 Concentration Substituted: 68
Operating Hours Stack Gas Flow Rate Substituted: 24
Operating Hours Stack Gas Moisture Substituted:

Electricity Fuel Details:
Fuel type: Subbituminous
Annual heat input:  8742421 (mmBtu)
CH4 Emissions CO2 Equivalent:  218.6  (Metric Tons)
N2O Emissions CO2 Equivalent:  4168.4  (Metric Tons)