COMPLIANCE ASSURANCE MONITORING 

MINNKOTA POWER COOPERATIVE, INC. 

Milton R Young Station 

February 1, 2010 

Page 1 of 23 
MINNKOTA POWER COOPERATIVE, INC. 

Milton R. Young Station 

Compliance Assurance Monitoring Plan 

Electrostatic Precipitator 

I. Background 

A. Emission Units: Lignite-fired boilers 

Description: Electrostatic Precipitator (ESP) 

EP 1 Location: Unit 1 

EP 2 Location: Unit 2 

B. Applicable Regulation, Emission Limit and Monitoring Requirements 

Unit 1 

Regulation: Title V Permit Number T5-F76009, NDAC 33-15-05-01.2 

Emission Limit: 

Opacity 20% 

Particulate: 

EP 1- 0.10 lb/106BTU 

PMIO: 

EP 1 - 160.3 lb/hr 

Unit 2 

Regulation: Title V Permit Number T5-F76009, NDAC 33-15-12, 

Subpart D and 33-15-03-02 

Emission Limit: 

Opacity 20% 

Particulate: 

EP 2- 0.03 lb/106BTU 

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PMIO: 

EP 2 - 315.1 lb/hr 

II. Monitoring Approach 

The key elements of the monitoring approach are presented in Table 1. 

Table No. 1 

Monitoring Approach 

ESP for PM Control 

Emission Points: 1 & 2 

Indicator No. 1 

I. Indicator Stack Opacity 

The opacity is measured using a 

Continuous Opacity Monitor (COMS) 

Measurement Approach at the stack of both units 

An excursion is defined as a measured 

stack opacity greater than 20 percent, 

based on a 3-hour block average. 

excluding startup/shutdown and 

malfunctions. Excursions trigger a 

reporting requirement. 

Corrective action must be initiated when 

measured stack opacity is greater than 

20 percent based on a 1-hour block 

II. Indicator Range average. 

III. Performance Criteria 

Opacity is related to particulate 

emissions. As opacity increase it can 

Data be assumed the particulate emissions 

Representativeness increase. 

Daily zero and span calibrations, 

cleaning of the optical surface of the 

QA/QC COMS, QA/QC checks per applicable 

Performance Specification 1. 

Monitoring Frequency Continuous 

The COMS records a 1 minute opacity 

average which is averaged for 1 minute, 

Averaging Period 6 minute and 1 hour averages. 

Evaluate the cause of the increased 

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opacity. The evaluation will include 

the ESP rappers, ESP electrical 

components, ash removal and ash 

transport systems. Corrective actions 

will be completed as soon as practically 

possible. A reduction of the generator 

electrical output to reduce ash loading to 

Corrective Action the ESP if necessary. 

MONITORING APPROACH JUSTIFICATION 

I. Background 

The Milton R. Young Station consists of two cyclone-fired boilers. Each of the boilers exhaust through 

dedicated stacks. Unit 1 has a rated heat input of 3200 X 106 BTU/hr and Unit 2 has a rated heat input of 

6200 X 106 BTU/hr. Both boilers fire lignite and Number 2 fuel oil during startup and to clear the 

cyclone burners of slag. 

Particulate emissions are controlled by, two side by side cold side ESP's per unit. Each of the Unit 

ESP's consists of eight transformer rectifier (TR) sets. The Unit 2 ESP's consist of sixteen TR sets. 

II. Justification for Selected Performance Indicators 

A test and cap approach was taken to determine the particulate emissions at or near 20 percent opacity. If 

the particulate emission limits, are determined not to be exceeded at 20 percent opacity two triggers are 

set. The first trigger point indicates a possible problem with the COMS, ESP or the ash transport system 

and action should be taken. The second trigger is an excursion and is a reportable event under 

Compliance Assurance Monitoring CAM. 

Unit 1 Test Results 

Table 2, Figure 1 and Figure 2 show the results of the particulate testing completed on Unit 1. 

Total 

Stack Particulate PMIo 

Opacity Emissions Emissions 

Condition (0/0) (lb/106BTU) ( b/hr) 1

Baseline 3.1 0.0074 15.23 

Baseline 3.4 0.0071 16.24 

Baseline 5.0 0.0108 21.61 

De-tuned (mid) 11.5 0.0301 66.83 

De-tuned (mid) 11.6 0.0271 65.59 

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De-tuned (mid) 14.6 0.0442 112.96 

De-tuned (high) 14.8 0.0420 101.49 

De-tuned (high) 15.1 0.0397 80.22 

De-tuned (high) 20.8 0.0665 163.68 

Table 2. Unit 1 CAM Testing Results 

The Unit 1 emission limits for total particulate and PMio are 0.10 (lb/10 6BTU) and 160.3 (lb/hr) respectively. 

The data for the baseline condition shows an average opacity of 3. 8 percent and emissions of 0.0084 (lb/10 6 

BTU) for total particulate and 17.7 (lb/hr) for PM10, which are well below the respective emission limits. 

To achieve an increased opacity the ESP was de-tuned by shutting down or reducing power to TR sets. The mid 

range opacity on Unit 1 was achieved by shutting down 8 of 16 TR sets. The high range opacity was achieved 

by, shutting down 8 of 16 TR sets and reducing to 50 percent power 2 of the remaining 8 TR sets. 

ABl AB1 CD1 CD1 

AB2 AB2 02 CD2 

AB3. AB3; CD3 CD3 

A84 AB4 CD4 CD4 

AB5 AB5 CD5 CD5 

AB6 AB6 CD6 CD6 

AB7 AB7 CD7 CD7 

AB8 AB8 CD8 CD 

TR off 

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Unit 1 ESP De-tuned Mid Opacity 

AB1 ABl. CD1 CD1 

AB2 AB2 CD2 CD2 

AB3 AB3 CD3 CD3 

AB4 AB4 CD4 CD4 

AB5 .PiBS CDS CD5 

AB6 AB6 CD6 CD6 

AB7 AB7 CD7 CD7 

AB8 AB8 CD8 CD 

TR off TR %z, power 

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Unit 1 ESP De-tuned High Opacity 

JIF, 

0.10 

3 

m 0.08 

~ 

~ 0.06 .Q 

g 0.04 

a 

0.02 

o lil 

Unit 1 PM 

♦ Total Particulate 

Emission Limit 

0.0 5.0 10.0 15.0 20.0 25.0 

Opacity (%) 

Figure 1 

Figure 1 is a graph of opacity and total particulate for the Unit 1 performance testing for the baseline as 

well as the de-tuned ESP operating scenario at a normal generator output. The linear regression shows a 

worst-case scenario for particulate emissions at 20 percent opacity to be 0.062 (lb/10 6BTU). The 

particulate emissions under the worst-case scenario are about 62 percent of the permitted emission limit. 

Unit 1 PM 10 

180.0 

160.0 

140.0 

s 120.0 

~ 100.0 

° 80.0 

a 60.0 

40.0 

20.0 

0.0 

_ --- 

~ ~ 

~® 

~ ~ 

0.0 5.0 10.0 15.0 20.0 25.0 

Opacity (%) 

♦ PM10 

Emission Limit 

The data shows a margin for compliance with CAM. 

Page 7 of 23 
Figure 2 

Figure 2 is a graph of opacity and PM10 for the Unit 1 performance testing for the baseline as well as the 

de-tuned ESP operating scenario at a normal generator output. The linear regression shows a worst-case 

scenario for particulate emissions at 20 percent opacity to be 150 (lb/hr). The particulate emissions under 

the worst-case scenario are about 94 percent of the permitted emission limit. The data shows a margin for 

compliance with CAM. 

Unit 2 Test Results 

Table 3, Figure 3 and Figure 4 show the results of the particulate testing completed on Unit 2. 

Total 

Stack Particulate PMIo 

Opacity Emissions Emissions 

Condition °/a (lb/lO6BTU) ( b/hr) 1

Baseline 10.8 0.0059 23.96 

Baseline 11.0 0.0067 25.79 

Baseline 11.0 0.0063 25.14 

De-tuned (mid) 13.7 0.0127 47.05 

De-tuned (mid) 15.3 0.0121 54.37 

De-tuned (mid) 17.0 0.0165 80.88 

De-tuned (high) 19.3 0.0194 77.90 

De-tuned (high) 19.9 0.0228 89.78 

De-tuned (high) 20.0 0.0234 93.06 

Table 3. Unit 2 CAM Testing Results 

The Unit 2 emission limits for total particulate and PMIO are 0.03 (lb/10 6BTU) and 315.1 (lb/hr) 

respectively. The data for the baseline condition shows an average opacity of 10.9 percent and emissions 

of 0.0063 (lb/10 6BTU) for total particulate and 25.0 (lb/hr) for PMIo, which are well below the respective 

emission limits. 

To achieve an increased opacity the ESP was de-tuned by shutting down or reducing power to TR sets. 

The mid range opacity on Unit 2 was achieved by shutting down 16 of 32 TR sets. The high range 

opacity was achieved by, shutting down 16 of 32 TR sets and reducing to 50 percent power to 4 of the 

remaining 16 TR sets. 

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lA1 2A1 3A1 4A1 1B1 2B1. 3B1 4B1 

lA2 2A2 3A2 4A2 1B2 2B2 3B2 4B2 

lA3 2A3 3A3 4A3 1B3 2B3 3B3 4B3 

lA4 2A4 3A4 4A4 1B4 2B4 3B4 4B4 

TR o.ff 

Unit 2 ESP De-tuned Mid Opacity 

lAl 2A1. 3A1 4A1 lBl 2B1 381 4B1 

lA2 2A2 3A2 4A2 182 2B2 3B2 492 

1A3 2A3 3A3 4A3 1B3 2133 3B3 4B3 

lA4 2A4 3A4 4A4 1B4 2B4 3B4 4B4 

TR .Off TR Power 

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Unit 2 ESP De-tuned High Opacity 

Figure 3 

Figure 3 is a graph of opacity and total particulate for the performance testing for Unit 2 for the baseline 

as well as the de-tuned ESP operating scenario at a normal generator output. The linear regression shows 

a worst-case scenario for particulate emissions at 20 percent opacity to be 0.0234 (lb/10 6BTU). The 

particulate emissions under the worst-case scenario are about 78 percent of the permitted emission limit. 

The data shows a margin for compliance with CAM. 

Figure 4 

Figure 4 is a graph of opacity and PMIO for the Unit 2 performance testing for the baseline as well as the 

de-tuned ESP operating scenario at a normal generator output. The linear regression shows a worst-case 

scenario for particulate emissions at 20 percent opacity to be 93.06 (lb/hr). The particulate emissions 

under the worst-case scenario are about 30 percent of the permitted emission limit. The data shows a 

margin for compliance with CAM. 

The test data supports the propose test and cap approach using a 20 percent opacity measurement as the 

primary indicator to trigger both a corrective action and a excursion. In all cases the linear regression 

shows the opacity/mass relationship to be below both the total particulate and the PMIO emission limits. 

The selected indicator meet the design criteria outlined in 40 CFR Part 64. 

Record Keeping and Reporting Methods 

All measured visible emissions readings are stored on the data acquisition and handling (DAHS) computer 

hard drive for five years. The DAHS computers are located in the continuous emission monitor (CEM) 

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shelter at the base of the stack of each unit. All maintenance for the COMS is recorded in the 

maintenance log in the CEM shelter. These records will include the identification of the emission unit, 

description of maintenance if needed, date and the name of person completing the inspection. A 

Semi-annual Monitoring/permit Deviation Report and a Quarterly Excess emission Report will submitted 

to the North Dakota Department of Health. 

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I. Background 

MINNKOTA POWER COOPERATIVE, INC. 

Milton R. Young Station 

Compliance Assurance Monitoring Plan 

Fabric Filters 

A. Emission Units: Lime Storage & Fly Ash Storage 

Description: Fabric Filter 

Emission Point: M6 Location: Unit 2 Fly Ash Silo 

Emission Point: M7 Location: Unit 2 Lime Storage Silo 

Emission Point: M12 Location: Water treatment Plant Lime Storage Silo 

B. Applicable Regulation, Emission Limit and Monitoring Requirements 

Regulation: Title V Permit Number T5-F76009, NDAC 33-15-05-01 & 33-15-03-02 

Emission Limit: 

Opacity 20% for all emission points 

Particulate: 

M6 - 42.5 lb/hr 

M7 - 25.21b/hr 

M 12 - 4.4 lb/hr 

PMIO: 

M6 - 2.21b/hr 

M7 - 13.3 lb/hr 

II. Monitoring Approach 

The key elements of the monitoring approach are presented in Table 1. 

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Table No. 1 

Monitoring Approach 

Fabric Filter for PM Control 

Emission Points: M6, M7, & M12 

Indicator No. 1 

I. Indicator Visible Emissions 

Measurement Approach Visible Emissions Check 

II. Indicator Range If any detectable visible 

emissions are noted the plant 

employee will notify the 

appropriate personnel to have 

the control device repaired 

III. Performance Criteria 

QA/QC Plant personnel perform 

visible emissions check 

Monitoring Frequency Daily, if system is operating 

during the day 

Corrective Action Repair as soon as practically 

possible 

MONITORING APPROACH JUSTIFICATION 

I. Background 

Primary function is the storage of fly ash and lime. 

The monitoring approach outlined here applies to the fabric filters associated with the storage of fly ash 

and lime. The fabric filters control the particulate emissions associated with the storage of fly ash and 

lime. 

II. Justification for Selected Performance Indicators 

Visible emissions, was selected as a performance indicator based on our experience operating the fabric 

filters and the need to comply with the particulate emissions limits. Any visible sign of emissions 

indicates a reduction in the particulate removal efficiency of the fabric filters. 

III. Record Keeping and Reporting Methods 

All visible emissions records will be stored in the station file at the plant. These records will include the 

identification of the emission unit, description of maintenance if needed, date and the name of person 

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completing the inspection. A semi-annual monitoring/permit deviation report will submitted to the North 

Dakota Department of Health. 

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MINNKOTA POWER COOPERATIVE, INC. 

Milton R. Young Station 

Compliance Assurance Monitoring Plan 

Roto-clones 

I. Background 

C. Emission Units: Coal Handling 

Description: Rotoclone 

Emission Point: M 1 Location: Unit 1 Crusher House and Conveyor 1 C 

Emission Point: M2 Location: Unit 1 Coal Silos 

Emission Point: M3 Location: Unit 2 Crusher House 

Emission Point: M4 Location: Unit 2 Coal Silos 

D. Applicable Regulation, Emission Limit and Monitoring Requirements 

Regulation: Title V Permit Number T5-F76009, NDAC 33-15-05-01 & 33-15-03-02 

Emission Limit: 

Opacity 20% for all emission points 

Particulate: 

M 1 - 74.0 lb/hr 

M2 - 66.3 lb/hr 

M3 - 82.0 lb/hr 

M4 - 74.71b/hr 

PMio: 

M 1 - 4.3 lb/hr 

M2 - 7.51b/hr 

M3 - 18.71b/hr 

M4 - 18.51b/hr 

II. Monitoring Approach 

The key elements of the monitoring approach are presented in Table 1. 

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Table No. 1 

Monitoring Approach 

Rotoclone for PM Control 

Emission Points: Ml, M2, M3 & M4 

Indicator No. 1 Indicator No. 2 

I. Indicator Visible Emissions Ins ection/maintenance 

Measurement Approach Visible Emissions Check Daily inspection according to 

checklist: maintenance 

performed as needed 

II. Indicator Range If any detectable visible The indicator range is water 

emissions are noted the plant flow through the control 

employee will notify the device. 

appropriate personnel to 

have the control device 

repaired 

III. Performance Criteria 

QA/QC Plant personnel perform Plant personnel perform 

visible emissions check inspections 

Monitoring Frequency Daily, if system is operating Daily, if system is operating 

during the day during the day 

Corrective Action j Repair as soon as practically Repair as soon as practically 

possible possible 

MONITORING APPROACH JUSTIFICATION 

IV. Background 

Primary function of the coal handling equipment is coal crushing and delivery. 

The monitoring approach outlined here applies to the rotoclones associated with the coal handling 

equipment. The rotoclones control the particulate emissions associated with the coal handling 

equipment. 

V. Justification for Selected Performance Indicators 

Visible emissions, was selected as a performance indicator based on our experience operating the 

rotoclones and the need to comply with the particulate emissions limits. Any visible sign of emissions 

indicates a reduction in the particulate removal efficiency of the rotoclone. 

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Inspection/maintenance was selected as a performance indicator based on our experience operating the 

rotoclones and the need to comply with the particulate emissions limits. A plugged drain or a poor spray 

pattern of water in the rotoclone indicates a reduction in the particulate removal efficiency of the 

rotoclone. 

VI. Record Keeping and Reporting Methods 

All visible emissions and inspection/maintenance records will be stored in the station file at the plant. 

These records will include the identification of the emission unit, description of maintenance if needed, 

date and the name of person completing the inspection. 

A semi-annual monitoring/permit deviation report will submitted to the North Dakota Department of 

Health. 

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Attachment B 

Consent Decree - July 27, 2006 

Amendments to Permit No. T5476009 

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