# Meteorological and Hydrogen Cyanide (HCN) Perimeter Monitoring

Preliminary Report

M ARIGOLD 

# M INING 

# C OMPANY

P ROJECT 

## 235-3-4 January 2010Marigold Preliminary Hcn Monitoring Report.Docx 

### ii 

# CONTENTS Page

1.0 INTRODUCTION .............................................................................................................. ........................................... 1 1.1 HCN Monitor and Meteorological Station Locations .......................................................................... ..................... 1 1.2 HCN Monitoring System Description ......................................................................................... ............................. 5 1.3 Data Recovery ............................................................................................................. .......................................... 6 1.4 Quality Control ........................................................................................................... ............................................. 6

2.0 METEOROLOGY AT THE METEOROLOGICAL STATION ................................................................................. .... 7

2.1 Winds ..................................................................................................................... ................................................ 7 2.2 Temperature and Barometric Pressure ....................................................................................... ........................ 10

3.0 HCN STATION ............................................................................................................... .......................................... 11

3.1 Winds ..................................................................................................................... .............................................. 11 3.2 Temperature, Relative Humidity, and Barometric Pressure ................................................................... ............ 11 3.3 HCN Concentration ......................................................................................................... ..................................... 12

4.0 DATA ANALYSI S ............................................................................................................. ........................................ 13



## Tables

Table 1: Sensor Locations .................................................................................................... ........................................... 5 Table 2: Data Recovery ....................................................................................................... ............................................ 6 Table 3: Frequency of Hourly Averaged Winds by Direction and Speed ........................................................... .............. 8 Table 4: Frequency of Hourly Averaged Winds by Direction and Stability ....................................................... ................ 8 Table 5: Temperature and Barometric Pressure ................................................................................. ........................... 10 Table 6: Temperature and Relative Humidity ................................................................................... .............................. 11
Table 7: HCN Concentration ................................................................................................... ....................................... 12 Table 8: Measured HCN Concentration Analysis ................................................................................. .......................... 13



## Figures
Figure 1: HCN Monitoring Site ................................................................................................ ......................................... 2 Figure 2: Large Scale Area Map ............................................................................................... ....................................... 3 Figure 3: Refinery and Ponds ................................................................................................. ......................................... 4 Figure 4: Wind Frequency Distribution ........................................................................................ ..................................... 9 Figure 5: Measured HCN Concentration Analysis ................................................................................ ......................... 14 Figure 6: Wind frequency for December 30, 2009 (Lowest Concentration Day) .................................................... ........ 15 Figure 7: Wind frequency for December 18, 2009 (Highest Concentration Day) ................................................... ........ 15



## Appendices
Appendix A: Hourly Meteorological Data Appendix B: HCN Data Appendix C: Site Check Forms, Audits, and Calibration Appendix D: Hydrogen Cyanide (HCN) Fence Line Monitoring PlansMarigold Preliminary Hcn Monitoring Report.Docx 

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## SECTION 1 

# INTRODUCTION

This report summarizes the meteorological and hydrogen cyanide (HCN) data collected at the Marigold Mining Company (Marigold) meteorological station and HCN monitor through January 11, 2010. The HCN monitor station became operational on December 17, 2009, at 12:00 p.m. and the first 24-hour HCN sample was taken on December 18, 2009. The HCN monitoring equipment and sampling procedures followed Marigold’s Site-Specific Hydrogen Cyanid e (HCN) Perimeter Monitoring
Plan (Site Specific Plan), approved by EPA on November 10, 2009, and the general Hydrogen Cyanide (HCN) Fence Line Monitoring Plan , approved by EPA on October 9, 2009. The meteorological sampling procedures were performed in accordance with the U. S. EPA Quality Assurance Handbook of Air Pollution Measurement Systems Volume IV - Meteorological Measurements (EPA-600/R94-038D),
March 1995.

Marigold operates a gold mining facility located approximately four miles south of Interstate 80 at the Valmy Interchange (Exit 216), in Humboldt County, Nevada. The Marigold facility consists of open-pit mining and gold recovery processes incl uding heap leaching, carb on adsorption, stripping and regeneration, electrowinning, retorting, and re fining. The leach solutions used in the gold recovery processes contain cyanide. These solutions have the potential for low levels of hydrogen cyanide (HCN) formation and emission to the atmosp here. To assess the ambient concentrations of HCN, Marigold installed and continues to operat e an HCN monitor downwind of the potential HCN sources, at the boundary of the project operations at the Marigold mine.



# 1.1 HCN Monitor and Meteorol ogical Station Locations

Aerial photos and shaded relief maps are provided in Figures 1 through 3. Figure 1 provides an aerial photo of the mine site, the project bounda ry, the potential HCN sources, and the HCN monitor location. Figure 2 provides a shaded relief map of the area surrounding the Marigold mine and shows the location of the HCN monitor. The meteorological station is co-located with the HCN monitor at 488,951 meters east, 4,511,675 meters north, UTM Zone 11N, NAD83, elevation 4,669 feet.

Figures 1 and 3 highlight the potential sources of HCN emissions at Marigold. These sources include a leach pad, pregnant and barren po nds, tanks containing cyanide solution, and a single stack for the electrowinning cells and pregnant and barren tank s at the refinery. A closer view of the HCN sources at the refinery and pond area is shown in Figure 3.Marigold Preliminary Hcn Monitoring Report.Docx 

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# 1.2 HCN Monitoring System Description

The HCN monitoring system consists of a data logger connected to a low-flow pump which is connected through sorbent tubes to an ambient air inlet. The sorbent tubes capture HCN in the ambient air and are sent to the ALS Laboratory Group in Salt Lake City, Utah for analysis. The lab analysis is based on NIOSH Method 6010. The sa mpling schedule follows a 1-in-3 day calendar and will continue for a total sampling period of two months.

During a run day, all meteorological parameters ar e collected at more frequent intervals and timeaveraged into 15-minute values. Wind speed and wi nd direction are collected at the meteorological station. Ambient temperature, relative humidity , and barometric pressure as well as flow rate through the sorbent tubes are collected at the HC N monitor. Ambient temperature and barometric pressure are also collected at the co-located meteorological station and serve as a quality check for the HCN monitor data. The parameters collected are shown in Table 1.

The measurement height of the inlet is two meters. The height of the wind instruments is 10 meters. All other parameters are measured at two meters.

Table 1: Sensor Locations (meters above the ground)



## Parameter Height Wind speed* 10.0
Wind direction* 10.0 Ambient temperature 2.0 Relative humidity 2.0 Barometric pressure* 2.0 Sampler Flow 2.0
*Wind data are from the meteorological station.



## The 15-minute averaged data from the meteorological station are sent electronically to Air Sciences Inc. (Air Sciences) where they are transferred into a database. The meteorological data from the HCN monitor are recorded by the onsite digital Data Acquisition System (DAS) equipped with cellular internet for data transfer. The parameters are digitally processed by the DAS into 15-minute averages. The 15-minute averages are transmitted to Air Sciences for quality assurance checks and population into the database. The 15-minute averag es from both the meteor ological station and the HCN monitor are used as input to the Air Sciences’ database for the calculation of one-hour averages.Marigold Preliminary Hcn Monitoring Report.Docx 

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# 1.3 Data Recovery

Data recovery rates for all paramete rs are presented in Table 2.

The meteorological data recovery rate was 100 percen t for all parameters at the meteorological station and at the HCN monitor, with the exception of ba rometric pressure from the HCN monitor. The barometric pressure sensor at the HCN monitor was faulty and was replaced on January 15, 2010. Barometric pressure data from the co-located meteor ological station was used in its stead. The data recovery rates at the meteorological and HCN station are above the recommended rate of 90 percent for all meteorological parameters, except, as noted above, for the barometric pressure at the HCN
monitor station itself.

The data recovery rate for the flow rate to the sorbent tubes was 100 percent; the data recovery rate
for the HCN concentration from the sorbent tubes wa s also 100 percent. Both parameters are above the recommended recovery rate of 75 percent.

Table 2: Data Recovery December 18, 2009 - January 11, 2010 (percent)



## Recorded Recommended

Parameter Observations Recovery Rate Recovery Rate Meteorological Station Wind speed 600 100.0 90
Wind direction 600 100.0 90 Ambient temperature 600 100.0 90 Barometric pressure 600 100.0 90
HCN Station Ambient temperature 216 100.0 90 Relative humidity 216 100.0 90 Barometric pressure * 0.0 90
Flow 216 100.0 75
HCN concentration 9 100.0 75
* The barometric pressure data from the HCN monitor was invalid due to a faulty sensor. Barometric pressure data from the co-located meteorological stat ion was used in its stead.



# 1.4 Quality Control

The primary meteorological quality objectives are based on U.S. EPA guideline documents (EPA454/4-87-007, Section 6.1.1, Ambient Monitoring Guidelines for Prevention of Significant Deterioration [PSD] and EPA-454/R-99-005, February 2000, Table 5-1., Meteorological Monitoring Guidance for Regulatory Modeling Applications). The quality control objectives for the HCN monitor can be found in Appendix D.Marigold Preliminary Hcn Monitoring Report.Docx 

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## SECTION 2 

# METEOROLOGY AT THE METEOROLOGICAL STATION

The instantaneous wind speed, wind direction, temp erature, and barometric pressure data collected at the meteorological station during the monitore d period were processed into hourly averages. Appendix A presents the hourly averages for each parameter in SAROAD (Storage and Retrieval of Aerometric Data) format. A summary of this data for each parameter is shown in the following

sections.



# 2.1 Winds

Hourly averaged winds measured at the site duri ng the sampling period are summarized in Table 3 as frequency distributions of winds by direction an d speed. The data period contains 25 days (600 hours) of complete wind information.

Figure 4 shows the distribution of hourly averag ed winds by direction and speed for the sampling period. The mean wind speed for the period was 1. 8 m/s (4.0 mph). The winds were fairly evenly distributed for the period and ranged from modera te to brisk. A breakdown of the wind speed profile for this period yields the following: Ther e were 2.0 percent calm wind speeds (<0.447 m/s), 53.7 percent of the winds were between 0.5 m/s (1.1 mph) and 1.5 m/s (3.4 mph), 41.4 percent of the winds were between 1.5 m/s and 5 m/s (11.2 mph), and 3.0 percent of the wind speeds were greater than 5 m/s.

Table 4 shows a frequency distribution of hourly av eraged winds by directio n and stability class. Stability classes A, B, and C indicate low-speed daytime winds, which are categorized as unstable or high-dispersion-potential winds with class A being the least stable. Stability classes E and F indicate the frequency of low-speed nighttime winds, whic h are categorized as stable or low-dispersionpotential winds with class E being the least stable. The D stability class is a mixture of daytime and nighttime winds, generally at higher speeds. This class is also referred to as neutral stability.

The lower-speed daytime winds (classes A, B, and C) made up 18.7 percent of the total winds and were predominately from the east to the east-south east. The lower-speed nighttime winds (classes E and F) constituted 56.8 percent of the total winds and were predominately from the southeast to the south-southeast with a secondary peak from the we st-southwest to the west-northwest. The higherspeed winds (class D) comprised 24.5 percent of the total winds and were predominately from the
west-southwest to the northwest.Marigold Preliminary Hcn Monitoring Report.Docx 

### 8 Direction A B C D E F All

N 0.0 0.7 0.7 1.2 0.3 0.7 3.5

NNE 0.0 0.5 0.5 0.7 0.3 0.8 2.8

NE 0.0 0.3 0.8 0.5 0.2 0.3 2.2

ENE 0.0 0.7 0.8 0.5 0.3 1.0 3.3

E 0.0 3.0 1.2 0.7 0.3 0.5 5.7

ESE 0.0 1.5 1.7 1.8 1.0 2.3 8.3

SE 0.0 0.3 1.3 2.3 1.7 4.5 10.2

SSE 0.0 0.0 0.2 0.3 2.2 4.2 6.8

S 0.0 0.2 0.5 1.5 0.8 4.0 7.0

SSW 0.0 0.0 0.0 1.2 0.8 3.8 5.8

SW 0.0 0.0 0.2 2.0 1.7 2.8 6.7

WSW 0.0 0.0 0.3 3.0 1.7 3.7 8.7

W 0.0 0.0 0.0 2.5 2.0 3.3 7.8

WNW 0.0 0.7 0.3 2.3 1.7 3.3 8.3

NW 0.0 0.2 0.8 3.0 1.8 2.0 7.8

NNW 0.0 0.7 0.7 1.0 1.0 1.7 5.0

All 0.0 8.7 10.0 24.5 17.8 39.0 100.0 Stability Class 

### Table 3: Frequency of Hourly Averaged Winds by Direction and Speed December 18, 2009 - January 11, 2010 (percent of occurrence)



## Calm (< 0.447 m/s) = 2.0% Mean wind speed = 1.8 m/s Data presented as direction from which wind is blowing.

Table 4: Frequency of Hourly Averag ed Winds by Direction and Stability December 18, 2009 - January 11, 2010 (percent of occurrence) 

### Mean

Direction 0.5 <1.5 1.5 <3 3 <5 5 <7 7 <10 >=10 All Speed

N 2.5 0.2 0.2 0.3 0.0 0.0 3.2 1.7

NNE 2.5 0.2 0.0 0.0 0.0 0.0 2.7 1.0

NE 1.8 0.0 0.0 0.0 0.0 0.0 1.8 1.0

ENE 3.0 0.3 0.0 0.0 0.0 0.0 3.3 1.1

E 2.7 2.7 0.3 0.0 0.0 0.0 5.7 1.5

ESE 3.5 4.0 0.8 0.0 0.0 0.0 8.3 1.8

SE 4.8 4.3 1.0 0.0 0.0 0.0 10.2 1.8

SSE 4.3 1.7 0.5 0.0 0.0 0.0 6.5 1.4

S 4.0 2.7 0.3 0.0 0.0 0.0 7.0 1.5

SSW 3.2 2.7 0.0 0.0 0.0 0.0 5.8 1.5

SW 2.7 2.7 1.2 0.2 0.0 0.0 6.7 2.1

WSW 4.2 2.3 1.2 1.0 0.0 0.0 8.7 2.2

W 4.2 3.2 0.5 0.0 0.0 0.0 7.8 1.7

WNW 3.8 3.0 0.8 0.2 0.2 0.0 8.0 2.0

NW 3.7 2.7 0.7 0.3 0.2 0.2 7.7 2.2

NNW 2.8 1.2 0.2 0.5 0.0 0.0 4.7 1.9

All 53.7 33.7 7.7 2.5 0.3 0.2 98.0 1.8 Speed Class Intervals (m/s)Marigold Preliminary Hcn Monitoring Report.Docx 

### 9 Figure 4: Wind Frequency Distribution



### 1%

2%

3%

4%

5%

6%

7%

8%

9%

10% N

NNE

NE

ENE

E

ESE

SE

SSE
S SSW SW WSW W WNW NW NNW

0.5 1 5 8 10 m/s

15-Minute Met Data Wind Frequency Distribution: 12/18/09 - 01/11/10 Calm = 161 Missing = 0 Number of non-calm/missing = 2,239Marigold Preliminary Hcn Monitoring Report.Docx 

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# 2.2 Temperature and Barometric Pressure

The temperature mean and extremes for the sampling period are presented in Table 5. The average 2-meter temperature for the period was -3.8 ° C (25.2 ° F). The maximum hourly averaged 2-meter temperature was 7.6 ° C (45.7 ° F) and occurred on the afternoon of January 10, 2010. The minimum hourly averaged 2-meter temperature was -18.0 ° C (-0.4 ° F) and occurred on the morning of December
26, 2009.

Barometric pressure data collected during the sa mpling period are summarized in Table 5. The average barometric pressure for the period was 25.45 inHg (646 mmHg). The maximum hourly averaged barometric pressure for the period was 25.62 inHg (651 mmHg) and occurred for two consecutive hours in the morning of December 24 , 2009. The minimum hourly averaged barometric pressure for the period was 25.01 inHg (635 mmHg) and occurred for four consecutive hours in the morning of December 22, 2009.

Table 5: Temperature and Barometric Pressure December 18, 2009 - January 11, 2010



## Parameter Temperature ( ° C) 

## Barometric
Pressure (inch Hg) Avg. -3.8 25.45
Max. 7.6 25.62
Min. -18.0 25.01Marigold Preliminary Hcn Monitoring Report.Docx 

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## SECTION 3 

# HCN STATION

The instantaneous temperature, relative humidity, and barometric pressure data collected at the HCN monitor on each run day duri ng the monitored period were processed into hourly averages. Appendix A presents the hourly averages for each parameter in SAROAD (Storage and Retrieval of Aerometric Data) format. A summary of this data for each parameter is shown in the following

sections.



# 3.1 Winds

Wind data is from the co-located meteor ological station - see Section 2.1 above.


# 3.2 Temperature, Relative Humi dity, and Barometric Pressure

The temperature mean and extremes for the sampling period are presented in Table 6. The average 2-meter temperature for the period was -3.58 ° C (25.56 ° F). The maximum hour ly averaged 2-meter temperature was 7.90 ° C (46.22 ° F) and occurred on the afternoon of December 18, 2009. The minimum hourly averaged 2- meter temperature was -17.49 ° C (0.52 ° F) and occurred on the morning of December 24, 2009.

The relative humidity mean and extremes for the sampling period are presented in Table 6. The average relative humidity for the period was 45 percent. The minimum hourly average was 37 percent and the maximum was 51 percent.

As discussed in Section 1.3, the barometric pressure data from the co-located meteorological station was utilized during the sampling period (Decembe r 18, 2009, through January 11, 2010). Valid barometric pressure data from the HCN monitor statio n itself began collecting on January 15, 2010, at 2:30 pm, following installation of a new sensor.

Table 6: Temperature and Relative Humidity December 18, 2009 - January 11, 2010



## Parameter Temperature ( ° C) 

## Relative Humidity (%) Avg. -3.58 45
Max. 7.90 51
Min. -17.49 37Marigold Preliminary Hcn Monitoring Report.Docx 

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# 3.3 HCN Concentration

For the calculation of HCN concentration at standard conditions, 1 

## the barometric pressure from the meteorological station, which is co-loc ated with the HCN monitor, was used.

The HCN concentration data collected during the sa mpling period are summarized in Table 7. The average HCN concentration, corrected to standard conditions, was 2.27 μg/m 3 

## . The minimum HCN concentration for the period was 0.58 μg/m 3 

## and occurred on December 30, 2009. The maximum HCN concentration for the period was 7.34 μg/m 3 

## and occurred on December 18, 2009.

Table 7: HCN Concentration December 18, 2009 - January 11, 2010 (μg/m 3 

### )



## HCN Concentration

Run Day* Actual
Conditions Standard
Conditions 12/18/2009 6.82 7.34 12/21/2009 0.83 0.90 12/24/2009 1.34 1.37 12/27/2009 1.26 1.31 12/30/2009 0.54 0.58 01/02/2010 3.25 3.49 01/05/2010 2.50 2.64 01/08/2010 0.70 0.75 01/11/2010 1.92 2.07 Average 2.13 2.27

*Start time = 0:00:02; stop time = 0:00:00.



## The average HCN concentration of 2.27 μg/m 3 

## is below the EPA lifetime exposure reference concentration of 3E-3 mg/m 3



## . 2 

## The maximum HCN concentration of 7.34 μg/m 3 

## is two orders of magnitude below the National Institute for Occupational Safety and Health (NIOSH) recommended short-term exposure limit of 4,700 ppb (5,190 μg/m 3 

## ). 3 

## In addition, the EPA reference concentration of 3E-3 mg/m 3 

## was developed with a total uncertainty fact or of 1,000, where the Lowest Observed Adverse Effect Level (LOAEL) was 7,070 μg/m 3



## . 2

1 Standard conditions are 1 atmosphere and 25 ° C. 2 U.S. EPA Integrated Risk Information Syst em. http://www.epa.gov/iris/subst/0060.htm. 3 Occupational Safety and Health Guideline for Hydrogen Cyanide. http://www.osha.gov/SLTC/healthguideli nes/hydrogencyanide/recognition.htmlMarigold Preliminary Hcn Monitoring Report.Docx 

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## SECTION 4 

# DATA ANALYSIS

Based on the data collected from the first four week s of monitoring, an analys is of wind direction and measured HCN concentration was conducted. As shown in Figures 1 and 2, winds that blow from

206 ° through 244 ° (approximately south-southwest through we st-southwest) travel from the potential HCN sources at the Marigold mine towards the HCN monitor. The percent of winds blowing within this range of directions on each sample day is shown in Table 8 and Figure 5.

As shown by Table 8 and Figure 5, there does not appear to be a correlation between wind direction and measured HCN concentration. On the highest HCN concentration day, the winds blew from the potential HCN sources towards the monitor 21 perc ent of the time. However, on the lowest HCN concentration day, the winds blew from the potential HCN sources towards the monitor 42 percent of the time, which is the highest percent of winds bl owing towards the monitor of any of the sample days.

Table 8 also shows that there does not appear to be a correlation between wind speed and measured HCN concentration. The lowest and the second-hig hest HCN concentration days had the highest and second-highest average wind speed, respectively.

Table 8: Measured HCN Concentration Analysis December 18, 2009 - January 11, 2010



## HCN
Concentration Winds Blowing from HCN
Sources towards Monitor Average Wind Speed Run Day (μg/m 3 

## ) No. of Hours Percent (m/s) 12/18/09 7.34 5 21 1.4 12/21/09 0.90 2 8 1.8 12/24/09 1.37 1 4 0.8 12/27/09 1.31 1 4 1.0 12/30/09 0.58 10 42 3.7 01/02/10 3.49 3 13 2.2 01/05/10 2.64 3 13 1.4 01/08/10 0.75 0 0 2.0 01/11/10 2.07 4 17 1.8 Average 2.27Marigold Preliminary Hcn Monitoring Report.Docx 

### 14 Figure 5: Measured HCN Concentration Analysis



## Figures 6 and 7 summarize the 24-hour wind dire ction (the direction from which the wind is blowing) and wind speed for the lowest and hi ghest HCN concentration days. The lowest HCN concentration was measured on December 30, 2009. The highest HCN concentration was measured on December 18, 2009. The winds were predominat ely from the southwest to the west-southwest on the lowest concentration day and from the east -southeast to the southwest on the highest concentration day. 0 5 10 15 20 25 30 35 40 45

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0PercentofWinds(%)HCNConcentration(μg/m3)



### Run Day HCN Concentration Percent of Winds Towards MonitorMarigold Preliminary Hcn Monitoring Report.Docx 

### 15 2%

4%

6%

8%

10%

12%

14%

16%

18%

20% N

NNE

NE

ENE

E

ESE

SE

SSE
S SSW SW WSW W WNW NW NNW

0.5 1 5 8 10 m/s

15-Minute Met Data Wind Frequency Distribution: 12/18/2009 Calm = 5 Missing = 0 Number of non-calm/missing = 91 4%

8%

12%

16%

20%

24%

28%

32%

36%

40% N

NNE

NE

ENE

E

ESE

SE

SSE
S SSW SW WSW W WNW NW NNW

0.5 1 5 8 10 m/s

15-Minute Met Data Wind Frequency Distribution: 12/30/2009 Calm = 0 Missing = 0 Number of non-calm/missing = 96 

### Figure 6: Wind frequency for December 30, 2009 (Lowest Concentration Day)

Figure 7: Wind frequency for December 18, 2009 (Highest Concentration Day)

# APPENDIX A 

# Hourly Meteorological DataDay 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Avg Max Min12/18/2009 1.3 1.8 1.2 0.8 1.4 1.1 1.6 0.8 1.2 1.5 1.5 1.3 0.8 1.0 1.0 1.8 2.8 2.5 2.0 2.4 1.6 1.4 0.7 0.5 1.4 2.8 0.512/19/2009 1.2 1.2 2.5 1.1 0.8 1.8 2.7 1.1 0.8 1.2 0.9 1.2 2.9 2.9 3.4 1.9 1.1 2.8 1.1 2.3 1.9 0.9 1.3 1.5 1.7 3.4 0.812/20/2009 1.4 2.3 1.2 2.2 2.2 1.9 1.5 1.3 2.0 1.1 2.9 2.1 3.9 3.6 3.0 2.1 2.4 2.0 1.5 0.9 1.2 2.3 2.7 2.8 2.1 3.9 0.912/21/2009 1.7 1.3 1.4 2.4 1.8 2.1 1.7 1.4 1.2 2.8 2.9 1.5 1.2 1.1 1.9 1.7 1.1 3.1 2.0 1.5 2.0 3.0 2.4 0.7 1.8 3.1 0.712/22/2009 1.1 1.9 2.8 4.6 3.6 7.1 10.0 9.1 6.7 6.1 5.1 6.2 5.2 6.3 5.9 4.0 3.0 4.8 5.2 3.6 2.7 2.6 2.9 2.0 4.7 10.0 1.112/23/2009 3.4 2.4 2.8 2.1 1.0 1.7 2.2 2.2 0.7 0.6 0.6 1.0 0.8 0.9 0.7 0.7 1.9 2.2 1.8 1.0 0.9 0.4 0.9 2.3 1.5 3.4 0.412/24/2009 0.8 0.6 1.2 0.9 0.9 0.7 1.0 0.8 0.4 0.6 0.3 0.6 0.8 0.9 0.4 0.5 0.8 1.1 0.8 0.9 1.6 1.1 0.8 0.7 0.8 1.6 0.312/25/2009 0.6 0.7 1.0 1.3 0.6 1.0 0.5 0.6 0.4 0.3 0.4 1.0 0.7 0.5 0.7 1.2 0.4 0.5 1.1 1.5 1.4 1.4 0.7 1.2 0.8 1.5 0.312/26/2009 1.5 1.3 1.1 2.1 0.5 0.9 0.7 0.3 0.6 0.5 1.0 0.8 1.0 1.5 1.9 1.0 0.7 0.7 1.2 1.9 0.5 0.9 0.8 0.8 1.0 2.1 0.312/27/2009 0.6 0.8 0.4 1.0 1.2 1.9 0.5 1.0 1.0 1.2 1.0 0.7 1.7 1.1 1.2 0.9 0.9 0.3 0.8 0.7 0.8 1.4 1.2 2.1 1.0 2.1 0.312/28/2009 1.2 1.4 0.6 1.3 0.8 1.9 2.0 0.7 0.5 0.8 0.5 0.6 0.8 1.4 1.3 0.8 1.3 1.0 0.7 0.8 2.1 1.7 0.9 1.3 1.1 2.1 0.512/29/2009 1.2 1.7 1.0 0.3 0.7 0.6 0.9 0.6 2.0 1.6 1.4 1.7 2.1 1.7 1.3 1.3 1.0 1.6 2.4 4.2 2.1 1.2 1.3 1.4 1.5 4.2 0.312/30/2009 3.0 2.6 3.7 4.7 2.6 3.5 2.3 3.8 4.3 3.9 4.3 4.2 3.9 4.1 4.0 1.7 4.1 4.8 5.2 4.7 4.0 3.9 3.4 1.5 3.7 5.2 1.512/31/2009 0.8 1.3 2.8 1.1 1.6 1.7 1.4 0.9 1.5 1.9 1.8 3.4 1.8 2.4 2.0 2.2 0.9 1.6 0.7 1.0 2.1 2.2 1.8 2.0 1.7 3.4 0.71/1/2010 2.1 2.9 1.4 1.2 0.8 0.9 2.5 1.7 1.2 2.7 2.3 1.5 1.1 1.9 1.4 1.1 1.7 1.7 2.3 2.5 5.0 6.2 5.7 5.4 2.4 6.2 0.81/2/2010 5.7 5.1 3.7 4.8 3.7 3.5 1.8 1.7 1.1 1.1 2.3 1.4 2.0 1.9 1.2 0.6 1.5 1.3 1.3 1.9 1.0 0.8 1.3 1.5 2.2 5.7 0.61/3/2010 1.1 0.9 1.1 1.3 0.8 1.3 1.1 0.8 0.5 0.9 1.5 1.5 1.5 1.5 1.7 1.7 0.7 0.7 1.5 0.7 1.4 0.6 0.8 1.2 1.1 1.7 0.51/4/2010 1.4 1.1 1.5 1.2 0.8 1.2 0.9 0.5 1.2 1.7 1.8 1.7 4.0 3.1 1.9 1.4 1.0 0.8 1.8 1.0 1.3 1.6 1.0 0.9 1.5 4.0 0.51/5/2010 1.5 1.7 1.1 1.0 0.9 1.7 0.9 1.1 1.4 1.6 1.6 1.8 1.2 1.4 1.5 1.5 2.6 1.3 0.9 2.0 2.0 0.7 1.2 0.9 1.4 2.6 0.71/6/2010 1.1 0.7 1.1 0.9 1.1 1.3 1.3 1.0 1.1 0.6 0.5 1.2 1.3 1.4 0.9 1.0 1.4 1.4 1.1 1.4 1.7 2.0 1.4 1.2 1.2 2.0 0.51/7/2010 1.2 1.2 1.5 2.1 2.5 1.4 1.0 1.9 2.5 2.3 2.7 1.9 1.5 1.8 2.0 1.3 1.5 0.6 1.4 2.8 2.7 2.2 1.7 1.1 1.8 2.8 0.61/8/2010 1.0 1.3 2.3 2.5 1.0 1.0 1.2 0.9 0.8 1.4 4.0 2.9 2.3 3.3 4.0 3.6 2.6 2.3 1.1 1.0 1.4 0.9 3.3 2.2 2.0 4.0 0.81/9/2010 3.0 3.0 1.4 2.6 1.5 2.3 0.9 1.1 1.0 1.2 0.5 1.1 2.1 1.6 1.3 1.1 0.9 1.8 0.9 1.5 2.3 1.8 1.6 1.3 1.6 3.0 0.51/10/2010 0.8 1.5 1.6 1.3 1.1 1.6 1.1 2.2 1.3 1.8 1.4 1.1 1.4 1.3 2.0 1.6 1.9 1.2 1.6 2.0 2.7 1.6 0.8 2.4 1.6 2.7 0.81/11/2010 1.5 1.4 1.7 1.5 1.9 1.3 0.9 1.0 1.8 0.8 2.6 1.8 2.5 1.9 1.5 3.1 1.9 1.2 2.1 2.2 1.5 1.2 3.3 3.3 1.8 3.3 0.8Avg 1.6 1.7 1.7 1.9 1.4 1.8 1.7 1.5 1.5 1.6 1.8 1.8 1.9 2.0 1.9 1.6 1.6 1.7 1.7 1.9 1.9 1.8 1.8 1.7 1.7‐‐ ‐‐Max 5.7 5.1 3.7 4.8 3.7 7.1 10.0 9.1 6.7 6.1 5.1 6.2 5.2 6.3 5.9 4.0 4.1 4.8 5.2 4.7 5.0 6.2 5.7 5.4‐‐10.0‐‐Min 0.6 0.6 0.4 0.3 0.5 0.6 0.5 0.3 0.4 0.3 0.3 0.6 0.7 0.5 0.4 0.5 0.4 0.3 0.7 0.7 0.5 0.4 0.7 0.5‐‐ ‐‐0.3SAROADforMarigold,MarigoldHCNChannel:WS_ms_10mMonth:12/18/09‐01/11/10HourofdayDay 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Max Min12/18/2009 174 170 182 268 301 309 177 101 159 305 39 2 354 130 179 124 176 213 215 226 219 168 217 144 354 212/19/2009 192 317 283 318 228 248 276 129 308 350 20 105 120 115 119 116 137 203 261 229 198 212 265 215 350 2012/20/2009 285 280 250 327 258 299 254 268 309 247 119 172 136 126 122 202 123 291 157 64 160 138 141 283 327 6412/21/2009 257 258 242 141 239 293 283 74 138 131 323 329 299 113 127 114 51 300 16 198 261 140 97 111 329 1612/22/2009 140 179 222 308 288 305 304 304 294 313 331 342 345 359 351 350 305 310 317 337 270 273 276 209 359 14012/23/2009 254 260 240 142 54 170 215 312 75 101 349 55 352 81 38 34 255 180 173 188 164 301 178 146 352 3412/24/2009 152 339 300 150 148 174 211 91 334 351 2 59 66 45 21 92 280 295 187 206 113 186 170 137 351 212/25/2009 6 291 262 120 197 150 240 108 35 11 38 69 16 84 12 46 287 225 281 228 142 216 300 137 300 612/26/2009 144 153 281 306 222 173 166 168 175 322 19 322 7 333 297 36 160 265 287 280 210 137 153 137 333 712/27/2009 67 239 319 350 313 303 307 132 129 23 334 15 92 80 81 24 56 154 181 259 261 198 177 142 350 1512/28/2009 226 283 152 150 349 284 158 209 85 78 352 55 336 303 326 304 288 228 162 237 123 130 121 130 352 5512/29/2009 337 307 338 335 289 261 201 127 354 104 114 94 105 111 104 171 206 197 235 222 157 121 162 127 354 9412/30/2009 158 175 244 261 235 236 296 283 244 237 247 288 290 317 325 294 264 236 230 226 220 188 220 203 325 15812/31/2009 168 163 171 325 201 177 117 124 125 126 61 120 137 126 136 139 311 339 317 127 144 155 158 166 339 611/1/2010 149 139 342 227 119 127 122 110 177 105 118 119 88 122 8 59 198 222 192 199 249 250 247 247 342 81/2/2010 256 248 259 239 251 215 150 182 198 104 108 109 118 107 71 187 261 249 257 289 267 250 224 198 289 711/3/2010 276 171 136 179 123 257 168 162 356 273 87 77 86 94 91 314 283 188 247 208 173 247 109 176 356 771/4/2010 133 324 342 261 227 299 240 28 139 113 100 119 124 95 91 349 277 272 264 145 236 189 188 142 349 281/5/2010 223 298 257 335 303 294 215 315 300 178 99 91 86 136 104 333 240 141 108 158 73 276 192 195 335 731/6/2010 30 206 166 18 252 286 63 204 50 68 112 118 77 89 57 313 295 310 229 311 211 222 266 270 313 181/7/2010 118 288 253 262 295 337 252 258 271 318 339 337 308 344 338 321 309 248 241 269 280 265 233 338 344 1181/8/2010 155 60 308 300 245 264 264 332 160 321 118 125 137 127 126 119 127 136 313 296 245 20 152 125 332 201/9/2010 130 141 159 281 317 258 188 272 343 62 150 100 96 97 31 21 30 279 234 234 248 259 211 144 343 211/10/2010 236 117 127 158 203 163 337 307 303 318 355 94 96 84 98 79 310 271 177 196 203 243 337 274 355 791/11/2010 202 30 297 344 217 240 118 292 323 187 117 244 183 223 298 99 97 246 217 248 271 127 160 173 344 30Max 337 339 342 350 349 337 337 332 356 351 355 342 354 359 351 350 311 339 317 337 280 301 337 338 359‐‐Min 6 30 127 18 54 127 63 28 35 11 2 2 7 45 8 21 30 136 16 64 73 20 97 111‐‐2SAROADforMarigold,MarigoldHCNChannel:WD_10mMonth:12/18/09‐01/11/10HourofdayDay 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Avg Max Min12/18/2009 0.8 1.1 1.1 0.2‐0.8‐0.7‐1.2‐1.5 0.6 3.0 3.8 4.7 5.8 6.4 6.8 6.4 2.4 0.8 0.5 0.0‐0.3‐1.2‐1.6‐1.7 1.5 6.8‐1.712/19/2009‐1.7‐2.0‐2.1‐4.1‐4.3‐3.7‐5.1‐4.6‐3.2‐2.6‐2.0 0.7 2.6 3.1 4.3 3.2 1.0‐0.6‐0.9‐1.5‐1.6‐2.1‐2.7‐2.9‐1.4 4.3‐5.112/20/2009‐3.3‐2.8‐3.6‐4.5‐4.8‐4.6‐6.2‐4.6‐3.5‐3.9‐1.0 0.8 1.4 1.1 1.2 1.3 0.4‐1.2‐1.3‐1.3‐1.6‐2.4‐2.6‐3.4‐2.1 1.4‐6.212/21/2009‐3.3‐4.2‐4.1‐2.5‐3.5‐4.8‐4.3‐3.8‐2.0 0.3 0.0 0.6 2.4 3.3 2.9 2.8 1.5 0.8 0.5 0.0‐0.1‐0.1 0.0 0.1‐0.7 3.3‐4.812/22/2009 0.0‐0.5‐0.3‐0.6‐1.3‐2.5‐3.5‐4.5‐4.8‐4.4‐3.8‐3.6‐3.3‐3.4‐3.8‐4.9‐6.8‐6.2‐6.5‐7.5‐7.6‐7.7‐8.1‐7.6‐4.3 0.0‐8.112/23/2009‐7.7‐8.5‐10.4‐9.4‐9.1‐11.2‐12.4‐12.1‐13.5‐9.7‐8.0‐7.1‐6.0‐5.2‐4.6‐4.8‐8.9‐10.2‐10.4‐11.7‐11.6‐10.5‐12.9‐12.0‐9.5‐4.6‐13.512/24/2009‐12.8‐12.7‐13.7‐14.0‐14.8‐16.0‐15.5‐17.1‐15.3‐13.9‐11.8‐10.3‐9.0‐7.5‐6.9‐6.8‐9.5‐10.7‐13.6‐13.4‐11.8‐13.6‐13.2‐12.9‐12.4‐6.8‐17.112/25/2009‐13.0‐13.9‐14.5‐15.5‐17.1‐16.2‐15.7‐17.4‐16.2‐14.7‐13.5‐11.2‐10.3‐8.4‐7.3‐7.7‐10.7‐11.8‐11.9‐13.9‐12.9‐13.6‐12.5‐13.4‐13.0‐7.3‐17.412/26/2009‐15.1‐14.7‐14.6‐14.7‐15.4‐18.0‐16.9‐16.6‐16.3‐13.9‐12.5‐10.1‐8.0‐7.1‐6.0‐5.7‐9.7‐11.2‐9.9‐10.0‐11.0‐11.3‐8.9‐8.5‐11.9‐5.7‐18.012/27/2009‐10.1‐10.4‐10.2‐10.5‐12.0‐12.3‐10.6‐10.6‐9.4‐8.4‐8.6‐7.2‐5.0‐3.9‐3.2‐3.1‐4.3‐5.6‐7.9‐9.1‐10.4‐11.2‐10.4‐10.0‐8.5‐3.1‐12.312/28/2009‐11.0‐10.7‐12.1‐12.3‐11.4‐10.5‐13.1‐11.7‐11.2‐9.3‐7.7‐6.2‐5.1‐4.7‐4.4‐4.7‐6.0‐7.0‐6.6‐6.2‐6.1‐5.3‐5.8‐4.9‐8.1‐4.4‐13.112/29/2009‐5.7‐5.6‐6.6‐7.2‐7.1‐6.8‐6.4‐6.1‐5.5‐5.3‐4.1‐3.1‐2.8‐2.0‐1.9‐3.4‐4.0‐4.2‐3.2‐2.7‐3.2‐3.8‐4.1‐3.1‐4.5‐1.9‐7.212/30/2009‐1.7‐2.5‐1.2‐1.6‐0.9‐0.9‐1.0‐0.6‐0.5‐0.4 0.5 1.1 1.3 1.1 0.6‐0.1‐1.9‐2.8‐2.3‐2.9‐4.0‐5.5‐5.0‐6.8‐1.6 1.3‐6.812/31/2009‐8.5‐10.1‐11.7‐11.8‐12.0‐11.4‐11.9‐12.6‐9.2‐7.1‐5.6‐4.9‐3.7‐3.7‐3.0‐2.7‐3.0‐3.7‐4.1‐4.1‐4.0‐3.3‐3.9‐3.8‐6.7‐2.7‐12.61/1/2010‐4.0‐3.9‐3.6‐4.4‐3.9‐4.3‐3.1‐3.9‐2.9‐1.2 0.0 1.2 1.8 1.9 2.7 2.0 1.7 2.4 4.2 1.3 1.9 2.4 2.1 1.5‐0.3 4.2‐4.41/2/2010 2.0 2.4 1.1 1.8 0.5‐1.2‐2.4‐2.2 0.2 2.2 2.7 2.9 3.3 3.3 3.7 2.4‐1.9‐4.0‐3.3‐0.4 0.0‐1.8‐2.2‐4.8 0.2 3.7‐4.81/3/2010‐4.6‐5.9‐6.6‐7.0‐6.4‐7.8‐8.5‐9.1‐8.7‐5.0‐4.1‐2.5‐1.1 0.0 1.4‐0.4‐2.6‐5.6‐5.3‐5.4‐6.2‐5.6‐5.4‐6.9‐5.0 1.4‐9.11/4/2010‐7.3‐8.5‐7.8‐10.0‐9.7‐10.7‐10.8‐10.4‐8.2‐5.9‐4.7‐1.4 0.2 0.4 0.7‐0.4‐4.2‐5.5‐4.4‐4.8‐4.9‐6.2‐6.8‐6.5‐5.7 0.7‐10.81/5/2010‐7.8‐7.9‐7.0‐5.9‐6.1‐7.6‐7.7‐7.9‐7.1‐4.2‐3.1‐2.1‐1.6‐1.1‐0.1‐1.3‐3.3‐3.9‐3.5‐2.3‐2.4‐2.9‐2.8‐3.1‐4.3‐0.1‐7.91/6/2010‐3.5‐4.1‐3.5‐5.0‐4.0‐3.6‐4.6‐3.6‐2.3‐2.0‐0.3 1.0 2.2 2.7 2.6 1.8 1.3 0.8 0.8 0.9 0.6 1.3 2.1 2.1‐0.7 2.7‐5.01/7/2010 0.3 0.1 0.1 0.9 0.9 0.5 0.5 1.1 1.8 2.7 2.5 2.8 3.2 3.6 3.5 3.3 2.3 1.1 0.4 0.5‐0.2‐0.9‐1.5‐1.5 1.2 3.6‐1.51/8/2010‐2.7‐3.3‐3.5‐4.5‐4.7‐4.8‐4.9‐5.5‐4.7‐2.5‐1.3‐0.2 0.5 0.6 0.7 0.5 0.3‐0.1 0.0‐0.3 0.3 0.0‐0.2‐0.3‐1.7 0.7‐5.51/9/2010‐0.3‐0.2 0.0‐1.1‐1.9‐2.5‐2.7‐3.1‐1.0‐0.4 1.1 3.1 4.6 4.7 4.1 3.8 2.7 0.4 0.2‐0.2 0.2 0.4 0.0‐0.6 0.5 4.7‐3.11/10/2010‐0.6 0.3 0.7 0.8 0.5‐0.2‐1.5‐1.4‐0.2 0.0 2.3 3.7 5.9 6.8 7.5 7.6 4.6 2.1 0.9 0.5 0.6 0.7 0.0‐0.3 1.7 7.6‐1.51/11/2010‐0.3‐0.7‐1.1‐1.7‐2.3‐0.6‐1.5‐1.7‐1.5‐0.2 2.3 3.4 5.1 5.1 5.4 5.3 3.9 2.4 2.3 2.2 1.1 2.1 2.0 3.2 1.4 5.4‐2.3Avg‐4.9‐5.2‐5.4‐5.8‐6.1‐6.5‐6.8‐6.9‐5.8‐4.3‐3.1‐1.7‐0.6‐0.1 0.3‐0.2‐2.2‐3.3‐3.4‐3.7‐3.8‐4.1‐4.2‐4.3‐3.8‐‐ ‐‐Max 2.0 2.4 1.1 1.8 0.9 0.5 0.5 1.1 1.8 3.0 3.8 4.7 5.9 6.8 7.5 7.6 4.6 2.4 4.2 2.2 1.9 2.4 2.1 3.2‐‐7.6‐‐Min‐15.1‐14.7‐14.6‐15.5‐17.1‐18.0‐16.9‐17.4‐16.3‐14.7‐13.5‐11.2‐10.3‐8.4‐7.3‐7.7‐10.7‐11.8‐13.6‐13.9‐12.9‐13.6‐13.2‐13.4‐‐ ‐‐ ‐18.0SAROADforMarigold,MarigoldHCNChannel:Temp_2m_CMonth:12/18/09‐01/11/10HourofdayDay 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Avg Max Min12/18/2009 25.53 25.52 25.52 25.53 25.53 25.55 25.55 25.55 25.55 25.57 25.57 25.57 25.55 25.54 25.54 25.54 25.53 25.53 25.53 25.53 25.54 25.55 25.55 25.55 25.54 25.57 25.5212/19/2009 25.54 25.54 25.54 25.54 25.54 25.53 25.53 25.53 25.53 25.54 25.53 25.52 25.51 25.48 25.47 25.48 25.48 25.47 25.47 25.47 25.47 25.47 25.47 25.46 25.50 25.54 25.4612/20/2009 25.44 25.43 25.43 25.41 25.40 25.40 25.40 25.40 25.39 25.40 25.38 25.38 25.35 25.32 25.32 25.33 25.32 25.32 25.32 25.33 25.33 25.33 25.32 25.32 25.36 25.44 25.3212/21/2009 25.32 25.33 25.33 25.30 25.29 25.29 25.29 25.27 25.27 25.26 25.24 25.23 25.19 25.16 25.15 25.12 25.10 25.09 25.09 25.07 25.08 25.06 25.05 25.04 25.19 25.33 25.0412/22/2009 25.02 25.01 25.01 25.01 25.01 25.02 25.03 25.06 25.08 25.10 25.11 25.12 25.12 25.14 25.16 25.19 25.22 25.24 25.26 25.29 25.31 25.33 25.35 25.36 25.15 25.36 25.0112/23/2009 25.37 25.41 25.43 25.44 25.46 25.48 25.48 25.49 25.51 25.54 25.55 25.54 25.54 25.52 25.53 25.53 25.53 25.54 25.55 25.56 25.56 25.58 25.59 25.59 25.51 25.59 25.3712/24/2009 25.59 25.59 25.61 25.59 25.59 25.60 25.60 25.60 25.61 25.62 25.62 25.61 25.59 25.58 25.58 25.57 25.56 25.57 25.56 25.55 25.55 25.55 25.54 25.54 25.58 25.62 25.5412/25/2009 25.53 25.53 25.53 25.52 25.51 25.50 25.50 25.51 25.52 25.53 25.52 25.50 25.48 25.46 25.44 25.44 25.44 25.43 25.43 25.43 25.43 25.43 25.43 25.42 25.48 25.53 25.4212/26/2009 25.41 25.41 25.41 25.40 25.40 25.39 25.39 25.39 25.40 25.42 25.42 25.40 25.38 25.36 25.35 25.35 25.35 25.35 25.35 25.36 25.37 25.38 25.39 25.39 25.38 25.42 25.3512/27/2009 25.39 25.39 25.40 25.40 25.39 25.39 25.40 25.41 25.43 25.44 25.45 25.45 25.44 25.45 25.45 25.46 25.46 25.47 25.48 25.47 25.48 25.49 25.50 25.50 25.44 25.50 25.3912/28/2009 25.50 25.50 25.51 25.50 25.50 25.50 25.50 25.49 25.49 25.49 25.48 25.45 25.43 25.40 25.38 25.37 25.36 25.35 25.34 25.34 25.33 25.32 25.32 25.31 25.42 25.51 25.3112/29/2009 25.30 25.30 25.31 25.30 25.29 25.29 25.29 25.30 25.32 25.33 25.34 25.33 25.32 25.30 25.29 25.29 25.29 25.29 25.28 25.29 25.27 25.26 25.25 25.23 25.29 25.34 25.2312/30/2009 25.22 25.23 25.24 25.24 25.24 25.25 25.27 25.29 25.31 25.33 25.34 25.35 25.35 25.36 25.38 25.40 25.41 25.43 25.45 25.47 25.49 25.51 25.51 25.53 25.36 25.53 25.2212/31/2009 25.53 25.54 25.55 25.55 25.54 25.54 25.54 25.54 25.54 25.55 25.56 25.55 25.53 25.51 25.50 25.50 25.51 25.51 25.52 25.53 25.53 25.54 25.54 25.54 25.53 25.56 25.501/1/2010 25.54 25.53 25.53 25.52 25.51 25.51 25.51 25.53 25.54 25.54 25.54 25.52 25.51 25.48 25.45 25.44 25.43 25.43 25.44 25.43 25.43 25.43 25.44 25.45 25.49 25.54 25.431/2/2010 25.44 25.45 25.47 25.49 25.47 25.48 25.50 25.51 25.52 25.53 25.54 25.52 25.50 25.49 25.49 25.49 25.49 25.50 25.52 25.53 25.54 25.55 25.55 25.55 25.50 25.55 25.441/3/2010 25.54 25.54 25.55 25.54 25.54 25.55 25.56 25.56 25.57 25.58 25.58 25.57 25.55 25.53 25.52 25.53 25.53 25.52 25.53 25.53 25.53 25.53 25.54 25.53 25.54 25.58 25.521/4/2010 25.52 25.51 25.51 25.51 25.50 25.50 25.50 25.51 25.52 25.54 25.54 25.51 25.48 25.48 25.47 25.47 25.47 25.47 25.49 25.48 25.48 25.48 25.49 25.49 25.50 25.54 25.471/5/2010 25.48 25.49 25.49 25.48 25.47 25.47 25.47 25.47 25.50 25.50 25.50 25.49 25.48 25.46 25.45 25.46 25.46 25.46 25.47 25.47 25.48 25.49 25.49 25.49 25.48 25.50 25.451/6/2010 25.48 25.48 25.48 25.47 25.47 25.46 25.47 25.47 25.48 25.49 25.49 25.48 25.47 25.46 25.46 25.47 25.47 25.47 25.48 25.48 25.49 25.49 25.49 25.49 25.48 25.49 25.461/7/2010 25.48 25.48 25.49 25.49 25.49 25.49 25.49 25.49 25.50 25.52 25.54 25.52 25.51 25.50 25.50 25.50 25.51 25.52 25.52 25.52 25.52 25.53 25.53 25.53 25.51 25.54 25.481/8/2010 25.53 25.52 25.51 25.52 25.51 25.50 25.50 25.51 25.52 25.54 25.53 25.52 25.50 25.49 25.49 25.49 25.50 25.51 25.51 25.52 25.53 25.54 25.55 25.55 25.51 25.55 25.491/9/2010 25.55 25.55 25.55 25.54 25.54 25.54 25.54 25.56 25.58 25.59 25.59 25.58 25.55 25.53 25.53 25.53 25.52 25.52 25.53 25.53 25.52 25.52 25.52 25.52 25.54 25.59 25.521/10/2010 25.52 25.52 25.54 25.54 25.54 25.54 25.55 25.55 25.55 25.57 25.57 25.56 25.54 25.53 25.53 25.53 25.53 25.54 25.55 25.55 25.56 25.57 25.58 25.58 25.55 25.58 25.521/11/2010 25.58 25.57 25.57 25.56 25.55 25.54 25.54 25.54 25.55 25.55 25.54 25.51 25.48 25.46 25.45 25.44 25.42 25.42 25.41 25.41 25.41 25.40 25.39 25.37 25.48 25.58 25.37Avg 25.45 25.45 25.46 25.45 25.45 25.45 25.46 25.46 25.47 25.48 25.48 25.47 25.45 25.44 25.44 25.44 25.44 25.44 25.44 25.45 25.45 25.45 25.45 25.45 25.45‐‐ ‐‐Max 25.59 25.59 25.61 25.59 25.59 25.60 25.60 25.60 25.61 25.62 25.62 25.61 25.59 25.58 25.58 25.57 25.56 25.57 25.56 25.56 25.56 25.58 25.59 25.59‐‐25.62‐‐Min 25.02 25.01 25.01 25.01 25.01 25.02 25.03 25.06 25.08 25.10 25.11 25.12 25.12 25.14 25.15 25.12 25.10 25.09 25.09 25.07 25.08 25.06 25.05 25.04‐‐ ‐‐25.01SAROADforMarigold,MarigoldHCNChannel:BP_inHg_2mMonth:12/18/09‐01/11/10HourofdayDay 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Avg Max Min12/18/2009‐0.15‐0.07‐0.19‐0.30‐0.33‐0.97‐1.83‐1.63‐2.21‐2.39‐1.24 1.12 3.19 4.83 6.46 7.69 7.90 6.87 3.06‐0.29‐1.19‐1.68‐2.14‐2.73 0.91 7.90‐2.7312/19/200912/20/200912/21/2009‐4.31‐4.44‐4.61‐4.98‐5.50‐4.71‐4.29‐5.56‐5.19‐4.44‐3.52‐1.17 0.15 0.24 1.92 3.07 2.63 2.17 1.33 0.19‐0.41‐0.75‐0.74‐0.62‐1.81 3.07‐5.5612/22/200912/23/200912/24/2009‐14.09‐13.94‐14.35‐15.23‐15.11‐15.99‐16.06‐16.74‐17.27‐17.49‐16.01‐13.20‐9.91‐7.02‐5.45‐4.40‐4.02‐4.74‐8.34‐12.37‐14.28‐14.92‐14.23‐14.76‐12.49‐4.02‐17.4912/25/200912/26/200912/27/2009‐10.16‐11.22‐11.60‐11.49‐12.14‐13.52‐12.40‐11.38‐9.90‐7.89‐6.92‐5.40‐3.08‐2.48‐1.05‐0.95‐3.75‐5.78‐8.44‐10.35‐12.07‐12.77‐12.62‐12.34‐8.74‐0.95‐13.5212/28/200912/29/200912/30/2009‐2.92‐3.07‐2.54‐2.53‐2.15‐2.02‐1.80‐1.62‐1.26‐0.62 0.66 1.74 2.19 2.55 1.76‐0.34‐2.81‐4.60‐4.28‐4.71‐5.92‐7.20‐7.03‐8.70‐2.38 2.55‐8.7012/31/20091/1/20101/2/2010‐0.01 0.91‐0.15‐0.70‐0.60‐3.02‐4.51‐4.75‐2.86 1.34 4.19 4.64 4.89 4.10 4.54 2.44‐2.18‐5.38‐5.68‐2.98‐1.63‐2.69‐3.77‐5.83‐0.82 4.89‐5.831/3/20101/4/20101/5/2010‐9.50‐9.58‐9.06‐7.15‐6.71‐7.96‐8.53‐8.76‐7.69‐5.08‐2.38‐0.68‐0.21 0.02 0.45‐0.89‐3.90‐5.25‐5.10‐3.67‐3.02‐3.35‐3.49‐4.09‐4.81 0.45‐9.581/6/20101/7/20101/8/2010‐3.58‐4.68‐4.57‐5.26‐6.05‐6.39‐6.23‐6.45‐5.66‐3.61‐2.09‐0.63 0.43 0.56 0.64 0.22‐0.16‐0.55‐0.78‐0.68‐0.44‐0.37‐0.57‐0.74‐2.40 0.64‐6.451/9/20101/10/20101/11/2010‐1.88‐2.36‐2.57‐2.99‐3.21‐2.24‐1.93‐2.32‐1.91‐1.29 0.94 2.23 4.17 4.81 5.03 5.08 3.28 1.22 0.46 0.68‐0.09 0.19 0.86 1.40 0.32 5.08‐3.21Avg‐5.18‐5.38‐5.51‐5.63‐5.76‐6.31‐6.40‐6.58‐5.99‐4.61‐2.93‐1.26 0.20 0.85 1.59 1.33‐0.33‐1.78‐3.08‐3.80‐4.34‐4.84‐4.86‐5.38‐3.58‐‐ ‐‐Max‐0.01 0.91‐0.15‐0.30‐0.33‐0.97‐1.80‐1.62‐1.26 1.34 4.19 4.64 4.89 4.83 6.46 7.69 7.90 6.87 3.06 0.68‐0.09 0.19 0.86 1.40‐‐7.90‐‐Min‐14.09‐13.94‐14.35‐15.23‐15.11‐15.99‐16.06‐16.74‐17.27‐17.49‐16.01‐13.20‐9.91‐7.02‐5.45‐4.40‐4.02‐5.78‐8.44‐12.37‐14.28‐14.92‐14.23‐14.76‐‐ ‐‐ ‐17.49Non‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DaySAROADforMarigold,MarigoldHCNChannel:T_AMB_CMonth:12/18/09‐01/11/10HourofdayDay 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Avg Max Min12/18/2009 42 42 42 42 42 42 43 42 42 42 42 43 43 44 45 46 46 47 46 46 45 44 43 43 44 47 4212/19/200912/20/200912/21/2009 43 43 43 43 43 43 42 43 43 42 42 42 42 44 43 43 43 44 44 45 44 44 44 44 43 45 4212/22/200912/23/200912/24/2009 38 38 38 38 38 38 37 37 37 38 40 41 42 43 44 47 47 48 46 44 42 40 39 39 41 48 3712/25/200912/26/200912/27/2009 40 40 41 41 40 40 40 40 40 40 40 40 40 42 45 46 45 44 44 43 43 42 41 41 42 46 4012/28/200912/29/200912/30/2009 42 43 43 43 43 43 43 43 43 43 44 44 46 50 49 47 47 46 46 45 45 45 45 45 45 50 4212/31/20091/1/20101/2/2010 46 45 46 47 46 47 47 47 47 46 46 46 47 48 50 50 50 50 49 46 46 46 47 47 47 50 451/3/20101/4/20101/5/2010 46 46 46 46 46 46 46 46 46 45 45 46 46 46 47 49 50 49 48 47 47 47 47 47 47 50 451/6/20101/7/20101/8/2010 47 47 47 46 47 47 46 46 47 46 46 47 47 47 48 48 48 48 48 48 48 48 48 48 47 48 461/9/20101/10/20101/11/2010 48 49 49 49 49 48 48 49 49 49 48 48 48 49 50 50 51 51 51 50 50 50 49 49 49 51 48Avg 44 44 44 44 44 44 44 44 44 44 44 44 45 46 47 47 48 48 47 46 46 45 45 45 45‐‐ ‐‐Max 48 49 49 49 49 48 48 49 49 49 48 48 48 50 50 50 51 51 51 50 50 50 49 49‐‐51‐‐Min 38 38 38 38 38 38 37 37 37 38 40 40 40 42 43 43 43 44 44 43 42 40 39 39‐‐ ‐‐37Non‐Run‐DayNon‐Run‐DaySAROADforMarigold,MarigoldHCNChannel:RH_percentMonth:12/18/09‐01/11/10HourofdayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐DayNon‐Run‐Day

# APPENDIX B 

# HCN DataPage 1 of 2 Wed, 01/06/10 5:23 PM 

# ANALYTICAL REPORT

Tom Brauch Air Sciences, Inc. 1301 Washington Ave, Suite 200 Golden, CO 80401 Phone:

E-mail: (303) 988-2960 x 207

tbrauch@airsci.com Report Date January 06, 2010

Project Manager Rand Potter Workorder: 1000413 Purchase Order: Client Project ID: Air Sciences Inc 010410

235-3-5

Analytical Results
12/18/2009 1/4/2010 1000413001 Sample ID:
Lab ID: Media: Collected:
Received: SKC 226-28, Soda Lime-200/600 235312182009-1 Sampling Location: Marigold

Method:

Analyte ug/sample mg/m3 ppm 

## NIOSH 6010 Analyzed: 1/6/2010

RL (ug/sample)

0.21 NA 12 NA Hydrogen Cyanide



## 12/18/2009 1/4/2010 1000413002 Sample ID:
Lab ID: Media: Collected:
Received: SKC 226-28, Soda Lime-200/600 235312212009-2 Sampling Location: Marigold

Method:

Analyte ug/sample mg/m3 ppm 

## NIOSH 6010 Analyzed: 1/6/2010

RL (ug/sample)

0.21 NA 1.6 NA Hydrogen Cyanide



## 12/18/2009 1/4/2010 1000413003 Sample ID:
Lab ID: Media: Collected:
Received: SKC 226-28, Soda Lime-200/600 235312242009-3 Sampling Location: Marigold

Method:

Analyte ug/sample mg/m3 ppm 

## NIOSH 6010 Analyzed: 1/6/2010

RL (ug/sample)

0.21 NA 2.3 NA Hydrogen Cyanide



## 12/18/2009 1/4/2010 1000413004 Sample ID:
Lab ID: Media: Collected:
Received: SKC 226-28, Soda Lime-200/600 235312272009-1 Sampling Location: Marigold

Method:

Analyte ug/sample mg/m3 ppm 

## NIOSH 6010 Analyzed: 1/6/2010

RL (ug/sample)

0.21 NA 2.3 NA Hydrogen Cyanide 

## Sample Comments

1000413001 The back section had a reportable result indicating that the sampler may have been

overloaded. Results may be less than acutal.

1000413003 The back section had a reportable result indicating that the sampler may have been

overloaded. Results may be less than acutal.

Results Continued on Next Page

IHREP-V9.8Page 2 of 2 Wed, 01/06/10 5:23 PM 

# ANALYTICAL REPORT

Project Manager Rand Potter Workorder: 1000413 Purchase Order: Client Project ID: Air Sciences Inc 010410

235-3-5

Analytical Results

1000413004 The back section had a reportable result indicating that the sampler may have been

overloaded. Results may be less than acutal.

Report Authorization

Method: NIOSH 6010

Sarah E. Adamson Rosemary Hanks Analyst Peer Review

Phone: (801) 266-7700 Email: lab@datachem.com Web: www.datachem.com 

## Laboratory Contact Information ALS Laboratory Group (formerly DataChem Laboratorie s, Inc.) 960 W Levoy Drive Salt Lake City, Utah 84123

The results provided in this report relate only to the items tested. Samples were received in acceptable condition unles s otherwise noted. Samples have not been blank corrected unless otherw ise noted. This test report shall not be reproduced, except in full, without written approval of ALS Laboratory G roup.
ALS Laboratory Group is accredited by AIHA for spec ific fields of testing as documented in its current scope of accreditation (ID#101574) which is available on request by contac ting your project manager or view on the internet a t http://www.aiha.org. The quality systems implemented in the laboratory apply to all methods performed by ALS Laboratory Group r egardless of this current scope of accreditation which does not include perfo rmance based methods, modified methods, and methods applied to matrices not listed in the methods.
ALS DataChem provides professional analytical servi ces for all samples submitted. ALS Laboratory Grou p is not in a position to interpret the data and assumes no responsibility fo r the quality of the samples submitted.

All quality control samples processed with the samp les in this report yielded acceptable results unles s otherwise noted. 

## General Lab Comments

LOD = Limit of Detection = MDL = Method Detection L imit, A statistical estimate of method/media/instru ment sensitivity. LOQ = Limit of Quantitation = RL = Reporting Limit, A verified value of method/media/instrument sensit ivity. ND = Not Detected, Testing result not detected abov e the LOD or LOQ. ** No result could be reported, see sample comments for details. < This testing result is less than the numerical va lue. ( ) This testing result is between the LOD and LOQ and has higher analytical uncertainty than values a t or above the LOQ. 

## Definitions

IHREP-V9.8Page 1 of 2 Wed, 01/13/10 2:13 PM 

# ANALYTICAL REPORT

Tom Brauch Air Sciences, Inc. 1301 Washington Ave, Suite 200 Golden, CO 80401 Phone:

E-mail: (303) 988-2960 x 207

tbrauch@airsci.com Report Date January 13, 2010

Project Manager Rand Potter Workorder: 1000614 Purchase Order: Client Project ID: Marigold 235-3-5 010610

235-3-5

Analytical Results
12/30/2009 1/6/2010 1000614001 Sample ID:
Lab ID: Media: Collected:
Received: SKC 226-28, Soda Lime-200/600 235312302009-2 Sampling Location: Marigold

Method:

Analyte ug/sample mg/m3 ppm 

## NIOSH 6010 Analyzed: 1/12/2010

RL (ug/sample)

0.21 NA 1.1 NA Hydrogen Cyanide



## 1/2/2010 1/6/2010 1000614002 Sample ID:
Lab ID: Media: Collected:
Received: SKC 226-28, Soda Lime-200/600 2353122010-3 Sampling Location: Marigold

Method:

Analyte ug/sample mg/m3 ppm 

## NIOSH 6010 Analyzed: 1/12/2010

RL (ug/sample)

0.21 NA 7.0 NA Hydrogen Cyanide



## Report Authorization

Method: NIOSH 6010

Sarah E. Adamson Rosemary Hanks Analyst Peer Review

Phone: (801) 266-7700 Email: lab@datachem.com Web: www.datachem.com 

## Laboratory Contact Information ALS Laboratory Group (formerly DataChem Laboratorie s, Inc.) 960 W Levoy Drive Salt Lake City, Utah 84123

IHREP-V9.8Page 2 of 2 Wed, 01/13/10 2:13 PM 

# ANALYTICAL REPORT

Project Manager Rand Potter Workorder: 1000614 Purchase Order: Client Project ID: Marigold 235-3-5 010610

235-3-5

The results provided in this report relate only to the items tested. Samples were received in acceptable condition unles s otherwise noted. Samples have not been blank corrected unless otherw ise noted. This test report shall not be reproduced, except in full, without written approval of ALS Laboratory G roup.
ALS Laboratory Group is accredited by AIHA for spec ific fields of testing as documented in its current scope of accreditation (ID#101574) which is available on request by contac ting your project manager or view on the internet a t http://www.aiha.org. The quality systems implemented in the laboratory apply to all methods performed by ALS Laboratory Group r egardless of this current scope of accreditation which does not include perfo rmance based methods, modified methods, and methods applied to matrices not listed in the methods.
ALS DataChem provides professional analytical servi ces for all samples submitted. ALS Laboratory Grou p is not in a position to interpret the data and assumes no responsibility fo r the quality of the samples submitted.

All quality control samples processed with the samp les in this report yielded acceptable results unles s otherwise noted. 

## General Lab Comments

LOD = Limit of Detection = MDL = Method Detection L imit, A statistical estimate of method/media/instru ment sensitivity. LOQ = Limit of Quantitation = RL = Reporting Limit, A verified value of method/media/instrument sensit ivity. ND = Not Detected, Testing result not detected abov e the LOD or LOQ. ** No result could be reported, see sample comments for details. < This testing result is less than the numerical va lue. ( ) This testing result is between the LOD and LOQ and has higher analytical uncertainty than values a t or above the LOQ. 

## Definitions

IHREP-V9.8Page 1 of 2 Wed, 01/20/10 1:22 PM 

# ANALYTICAL REPORT

Tom Brauch Air Sciences, Inc. 1301 Washington Ave, Suite 200 Golden, CO 80401 Phone:

E-mail: (303) 988-2960 x 207

tbrauch@airsci.com Report Date January 20, 2010

Project Manager Rand Potter Workorder: 1001538 Purchase Order: Client Project ID: Air Sciences, INC 011510

235-3-5

Analytical Results
1/5/2010 1/15/2010 1001538001 Sample ID:
Lab ID: Media: Collected:
Received: SKC 226-28, Soda Lime-200/600 2353152010-1 Sampling Location: Marigold

Method:

Analyte ug/sample mg/m3 ppm 

## NIOSH 6010 Analyzed: 1/19/2010

RL (ug/sample)

0.21 NA 4.6 NA Hydrogen Cyanide



## 1/8/2010 1/15/2010 1001538002 Sample ID:
Lab ID: Media: Collected:
Received: SKC 226-28, Soda Lime-200/600 2353182010-2 Sampling Location: Marigold

Method:

Analyte ug/sample mg/m3 ppm 

## NIOSH 6010 Analyzed: 1/19/2010

RL (ug/sample)

0.21 NA 1.3 NA Hydrogen Cyanide



## 1/11/2010 1/15/2010 1001538003 Sample ID:
Lab ID: Media: Collected:
Received: SKC 226-28, Soda Lime-200/600 23531112010-3 Sampling Location: Marigold

Method:

Analyte ug/sample mg/m3 ppm 

## NIOSH 6010 Analyzed: 1/19/2010

RL (ug/sample)

0.21 NA 3.2 NA Hydrogen Cyanide



## Report Authorization

Method: NIOSH 6010

Sarah E. Adamson Rosemary Hanks Analyst Peer Review

Phone: (801) 266-7700 Email: lab@datachem.com Web: www.datachem.com 

## Laboratory Contact Information ALS Laboratory Group (formerly DataChem Laboratorie s, Inc.) 960 W Levoy Drive Salt Lake City, Utah 84123

IHREP-V9.8Page 2 of 2 Wed, 01/20/10 1:22 PM 

# ANALYTICAL REPORT

Project Manager Rand Potter Workorder: 1001538 Purchase Order: Client Project ID: Air Sciences, INC 011510

235-3-5

The results provided in this report relate only to the items tested. Samples were received in acceptable condition unles s otherwise noted. Samples have not been blank corrected unless otherw ise noted. This test report shall not be reproduced, except in full, without written approval of ALS Laboratory G roup.
ALS Laboratory Group is accredited by AIHA for spec ific fields of testing as documented in its current scope of accreditation (ID#101574) which is available on request by contac ting your project manager or view on the internet a t http://www.aiha.org. The quality systems implemented in the laboratory apply to all methods performed by ALS Laboratory Group r egardless of this current scope of accreditation which does not include perfo rmance based methods, modified methods, and methods applied to matrices not listed in the methods.
ALS DataChem provides professional analytical servi ces for all samples submitted. ALS Laboratory Grou p is not in a position to interpret the data and assumes no responsibility fo r the quality of the samples submitted.

All quality control samples processed with the samp les in this report yielded acceptable results unles s otherwise noted. 

## General Lab Comments

LOD = Limit of Detection = MDL = Method Detection L imit, A statistical estimate of method/media/instru ment sensitivity. LOQ = Limit of Quantitation = RL = Reporting Limit, A verified value of method/media/instrument sensit ivity. ND = Not Detected, Testing result not detected abov e the LOD or LOQ. ** No result could be reported, see sample comments for details. < This testing result is less than the numerical va lue. ( ) This testing result is between the LOD and LOQ and has higher analytical uncertainty than values a t or above the LOQ. 

## Definitions

IHREP-V9.8

# APPENDIX C 

# Site Check Forms, Audits, and Calibration

## Calibration Form 

## Marigold Air Quality and Meteorological Monitoring

Site: Marigold Technician: Brian Smith

Date: 12/16/2009 Site Conditions: Cold, Clear

Invalid Data Range: Before 12/16/2009 Logger Serial Number: 2965

Initial Prior to Departure Initials [] [] Data download (record date and time). BWS [] [] Time and date verified on datalogger. BWS [] [] Communications verified. BWS [] [] All public real-time values are confirmed and as expected. BWS 

### 0 WS/WD verification performed (complete audit form). N/A [] Temperature and RH verification performed (complete audit form). BWS 

### 0 Precipitation verification performed (complete audit form). N/A

Barometric pressure verification performed (complete audit form). BWS

# ~ Solar panel cleaned. BWS

Comments:

Site was installed and became operational on 12/16/2009

All sensors were calibrated

12/16/2009

Date:

235-3-12162009CALAQ-MET 1,\ I IZ**~** ( II "( -I \ I" '­



### Calibration Form 

## Marigold Air Quality and Meteorological Monitoring

Temperature and Relative Humidity

- Co-Located Calibration

Time: 13:00 to 14:00 PST

Relative Humidity Measured
Diff HM P45C Logger VWR Thermo Hygro

SN: D3250873 SN- 80357103 0.1 1. 15 1. 17
0.2 2. 15 2. 17
0.1 3. 16 3. 17
0.1 4. 17 4. 18
0.0 5. 17 5. 18
0.1 6. 17 6. 17
0.1 7. 16 7. 17
0.1 8. 17 8. 16
0.0 9. 16 9. 16
0.1 10. 17 10. 16
0.1 Time: 13:00 to 14:00 PST

Temperature

HMP45C Logger

SN: D3250873 l. 9.1
2. 9.2
3. 9.3
4. 9.3
5. 9.3
6. 9.5
7. 9.5
8. 9.5
9. 9.4
10. 9.5 Average Difference

Difference = Site**~** Measured Diff

-2
-2
-1
-1
-1
0
-1

0
1

Barometric Pressure

- Co-Located Calibration

Time: 13:00 PST

Barometric Pressure

Logger Reading mmHg
SN:D31400332
1. 639.2
2 639.3
3. 639.3
4. 639.4 Average Difference

"'Difference 

### = Site

- Measured Measured

VWR Thermo Hygro

SN- 80357103 l. 9.0
2. 9.0
3. 9.2
4. 9.2
5. 9.3
6. 9.4
7. 9.4
8. 9.4
9. 9.4
10. 9.4

Measured
Brunton Altimeter Diff • mmHg
SN:NA
1. 638 1.2
2. 638 1.3
3. 639 0.3 4. 639 0.4 

# I 0.81

Copy of 235-3-12162009CALAQ-MET 2 1

-0.6**,\ II** **~ ~(**  II " I' I ' C.



### Calibration Form 

## Marigold Air Quality and Meteorological Monitoring

HeN Sampler System

Time : 13 : 00 to 14 : 00 PST Temp 

# rC)

Inches Digital Flow (l/min) low
mV Pressure Transducer R a w Inche s Sampler Manometer Fl ow BIOS Pl /Pa Qa (Flow Meter)
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Notes for next trip:

# ;8**Iv ~**  12 / 16 /2 009

### Si~ature Date :

235-3-12162009CALAQ-MET 3

# APPENDIX D 

# Hydrogen Cyanide (HCN) Fence Line Monitoring Plans

# Site-Specific Hydrogen Cyanide (HCN) Perimeter Monitoring Plan

M ARIGOLD 

# M INING 

# C OMPANY

P ROJECT 

## 235-2-2 O CTOBER 

## 2009

### ii 

# CONTENTS Page

1 INTRODUCTION ................................................................................................................ ............................................ 1
1.1 Mine Description and Proposed Monitoring .................................................................................. .......................... 1

2 METEOROLOGY ................................................................................................................. .......................................... 2
2.1 Prevailing Wind Direction ................................................................................................. ....................................... 2

3 PROPOSED HCN MONITORING SITE ................................................................................................ ......................... 5 3.1 Operations Boundary and Nearest Population Areas .......................................................................... ................... 5 3.2 Potential Sources of HCN .................................................................................................. ..................................... 5 3.2.1 Leach Pads .............................................................................................................. ....................................... 5 3.2.2 Refinery ................................................................................................................ ........................................... 5 3.3 Proposed HCN Monitor Location ............................................................................................. ............................... 5

4 PROPOSED MODIFICATIONS TO THE GENERAL HCN MONITORING PLAN ....................................................... 10



## Figures
Figure 2.1: Calendar Year 2008 Wind Rose ..................................................................................... ............................... 2 Figure 2.2: First Quarter 2008 Wind Rose ..................................................................................... .................................. 3 Figure 2.3: Second Quarter 2008 Wind Rose .................................................................................... .............................. 3 Figure 2.4: Third Quarter 2008 Wind Rose ..................................................................................... ................................. 4 Figure 2.5: Fourth Quarter 2008 Wind Rose .................................................................................... ................................ 4 Figure 3.1: Proposed HCN Monitoring Site ..................................................................................... ................................. 7 Figure 3.2: Large Scale Area Map ............................................................................................. ...................................... 8 Figure 3.3: Refinery and Ponds ............................................................................................... ........................................ 9



## Appendices
Appendix A: General HCN Monitoring Plan

### 1 

## SECTION 1 

# INTRODUCTION

1.1 Mine Description and Proposed Monitoring

Marigold Mining Company (Marigold) operates a gold mining facility located approximately four miles south of Interstate 80 at the Valmy Interchange (Exit 216), in Humboldt County, Nevada. The Marigold facility consists of open-pit mining and gold recovery processes including heap leaching, carbon adsorption, stripping an d regeneration, electrowinning, retoring, and refining. Leach solutions used in the gold reco very processes contain cyanide. These solutions have the potential for low levels of hydrogen cyanide (HCN) formation and emission to the atmosphere. To assess the ambient concentrations of HCN, Marigold plans to install and operate an HCN monitor downwind of the potential HC N sources, at the boundary of the project operations at the Marigold mine.

The HCN monitoring equipment and sa mpling procedures will follow the Hydrogen Cyanide (HCN) Fence Line Monitoring Plan , approved by EPA on October 9, 2009 (General HCN Monitoring Plan). This plan is provided in Appe ndix A. The purposes of the site-specific plan described herein are to identify the location where the monitor will be sited and to identify any modifications to the monitoring equipment and sampling procedures described in the General HCN Monitoring Plan that are specific to Marigo ld. Per EPA’s instructions, the site location takes into consideration the proximity of the HCN sources to public access areas and the prevailing wind direction. The site location also takes into consideration accessibility for the Marigold maintenance and project technicians.

The following sections describe the predominant wind direction, the Marigold project boundary, the nearest population areas to this boundary, the potential sources of HCN emissions and their locations at Marigold, and the proposed HCN monitoring site.

The HCN monitoring system proposed herein is a new system. Typically, a full field test and system verification of such a prototype monitor would be scheduled in advance of deploying the
monitor for data collection. This is done in orde r to identify system design problems, and refine the system configuration and operating and mainte nance procedures as appropriate. Due to the schedule that EPA has requested, only limited field testing and system verification will be possible prior to data collection. Because of this , it is possible that problems may arise with the monitoring system which will affect data collection and/or validity; however, Marigold will take all reasonable measures to avoid such problems in an effort to minimize any disruptions to the monitoring program.

### 2 

## SECTION 2 

# METEOROLOGY

2.1 Prevailing Wind Direction

Marigold currently operates a meteorological station. This station is located at 488,951 meters east, 4,511,675 meters north, UTM Zone 11N, NAD83, elevation 4,669 feet, approximately one mile northeast of the refinery. Figure 2.1 summar izes the hourly wind directions (the direction from which the wind is blowing) and wind speeds for the 2008 calendar year. Figures 2.2 through 2.5 provide wind roses for each calendar quarter of 2008. As shown by the annual and quarterly wind roses, the prevailing winds are fr om the west-northwest to southwest, with the most predominant annual wind di rection from the west-southwest.

Figure 2.1: Calendar Year 2008 Wind Rose

### 3 Figure 2.2: First Quarter 2008 Wind Rose

Figure 2.3: Second Quarter 2008 Wind Rose

### 4 Figure 2.4: Third Quarter 2008 Wind Rose

Figure 2.5: Fourth Quarter 2008 Wind Rose

### 5 

## SECTION 3 

# PROPOSED HCN MONITORING SITE

3.1 Operations Boundary a nd Nearest Population Areas

Aerial photos and shaded relief maps are provided in Figures 3.1 through 3.3. Figure 3.1 provides an aerial photo of the mine site, the project boundary, and the potential HCN sources. Figure 3.2 provides a shaded relief map of the ar ea surrounding the Marigold mine. The nearest residents are in the small town of Valmy located three miles north of the mine site, and in the
town of Battle Mountain located twelve miles southe ast of the mine site. Interstate 80 also passes approximately three miles northeast of the mine site.



# 3.2 Potential Sources of HCN

Figures 3.1 and 3.3 highlight the potential source s of HCN emissions at Marigold. These sources include a leach pad, pregnant and barren ponds, tanks containing cyanide solution, and a single stack for the electrowinning cells and pregnant and barren tanks at the refinery. A closer view of the HCN sources at the refinery and pond area is shown in Figure 3.3.



# 3.2.1 Leach Pads
Marigold operates one active leach pad. Cyanide leach solution is applied to portions of the pad primarily via drip emitters. Potential HCN emissions come from the cyanide solution applied to the ore on the pads, the pregnant ponds used to collect solution from the pads, and the barren ponds used to supply solution to the pads. Carbon-in-Column (CIC) tanks used to adsorb gold from the pregnant solution are al so potential HCN sources. The CIC tanks are located just north of the pregnant and barren ponds. The pad, ponds, and tanks are shown in Figures 3.1 and 3.3.


# 3.2.2 Refinery
The refinery area, shown in Figure 3.3, contains a single stack for the electrowinning cells and pregnant and barren tanks. Th e electrowinning cells and preg nant and barren tanks process aqueous cyanide solutions, which have the potent ial for HCN emissions. All of these units are within the refinery building, and the exhaust from these units is ducted through a carbon adsorption bed before being released to the atmosphere.


# 3.3 Proposed HCN Monitor Location

Marigold proposes to place the HCN monitor northeast of the potential HCN sources approximately one mile from the refinery and 1.3 miles from the edge of the leach pad, at the existing meteorological station. As shown in Figure 3.1, this location is in a favorable position to detect emissions from the potential HCN sources due to winds from the west-southwest to the
south-southwest. These wind directions account fo r 32 percent of the hourly winds, as shown by Figure 2.1. In addition, winds from the southwes t quadrant blow directly towards Interstate 80.

### 6 

## In the fourth quarter, when the monitoring will occur, the most predominant wind direction is
the southwest.

The proposed monitor location has line power and can be reached via a road maintained by Marigold. The proposed site coordinates are 48 8,951 meters east, 4,511,675 meters north, UTM Zone 11N, NAD83, elevation 4,669 feet.

### 10 

## SECTION 4 

# PROPOSED MODIFICATIONS TO THE GENERAL HCN MONITORING PLAN

Marigold does not propose any modifications to the General HCN Monitoring Plan with regards to the HCN sampling equipment. Marigold does, however, propose to use its existing meteorological station to collect the meteorologic al parameters (with the exception of relative humidity) outlined in the General HCN Monitoring Plan in lieu of installing the meteorological measurement equipment described in the general plan.

The existing station is located at the proposed HC N monitor site and, therefore, it will provide representative data for the overall mine and the monitor site. See Figure 3.1. The sensors for wind direction, wind speed, am bient temperature, and barometr ic pressure at the existing meteorological station meet the data quality objectives and criteria described in Section 2.1 of the General HCN Monitoring Plan. Because the existi ng station is not equippe d to measure relative humidity, this sensor will be installed at the HCN monitor site per the General HCN Monitoring Plan. The existing station is also audited on a quarterly basis.

As discussed in Section 3.3, line power is available at the proposed HCN monitor location. Therefore, the solar power system described in the General HCN Monitoring Plan will not be
needed.

# APPENDIX A 

# General HCN Monitoring Plan

# Hydrogen Cyanide (HCN) Fence Line Monitoring Plan

N EVADA 

# M INING 

# A SSOCIATION

P ROJECT 

## 59-43-70 O CTOBER 

## 2009Hcn Sampling Plan_V7.Docx 

### ii 

# CONTENTS Page

1 PROJECT MANAGEMENT ELEMENTS ................................................................................................. ...................... 1 1.1 Sampling Purpose .......................................................................................................... ........................................ 1 1.2 System Description ........................................................................................................ ......................................... 1

2 QUALITY OBJECTIVES AND CRITERIA FOR DATA MEASUREMENT ...................................................................... 3 2.1 Data Quality Objectives and Criteria ...................................................................................... ................................. 3

3 SPECIAL TRAINING REQUIREMENTS/CERTIFICATION ................................................................................. .......... 4

4 DOCUMENTATION OF RECORDS .................................................................................................... .......................... 5 4.1 Data Reporting Package Format and Documentation Control ................................................................... ............ 5

5 DATA GENERATION AND ACQUISITION ............................................................................................. ....................... 6 5.1 Sampling Process Design and Methods Requirements .......................................................................... ............... 6 5.1.1 Purpose ................................................................................................................. .......................................... 6 5.1.2 Sampling Network Design ................................................................................................. .............................. 6 5.1.3 Equipment Description ................................................................................................... ................................. 7 5.1.4 Data Logger ............................................................................................................. ........................................ 7 5.1.5 Wind Speed .............................................................................................................. ....................................... 7 5.1.6 Wind Direction .......................................................................................................... ....................................... 8 5.1.7 Temperature Sensor and Radiation Shield ................................................................................. .................... 8 5.1.8 Relative Humidity ....................................................................................................... ..................................... 8 5.1.9 Barometric Pressure ..................................................................................................... ................................... 8 5.1.10 HCN Sampling System .................................................................................................... .............................. 8 5.1.11 Power and Data Transfer ................................................................................................ ............................ 12 5.1.12 Meteorological Towers .................................................................................................. .............................. 12 5.2 Rationale for Design ...................................................................................................... ....................................... 12 5.3 Scheduled Measurement Activities .......................................................................................... ............................. 12 5.4 Measurement System Failure Response ....................................................................................... ....................... 13

6 SAMPLING METHOD REQUIREMENTS ................................................................................................ .................... 14 6.1 Sample Handling and Custody Requirements .................................................................................. .................... 14 6.2 Analytical Methods Requirements and Breakthrough Check .................................................................... ........... 14 6.3 Quality Control Requirements .............................................................................................. ................................. 14
7 INSTRUMENT/EQUIPMENT TESTING, INSPECTI ON, AND MAINTENANCE REQUIREMENTS ............................ 16

7.1 General Procedures ........................................................................................................ ...................................... 16 7.2 Instrument Calibration and Frequency ...................................................................................... ............................ 16 7.2.1 Calibration Equipment Maintenance ....................................................................................... ...................... 16 7.2.2 Calibration Records and Traceability .................................................................................... ........................ 17

8 INSPECTION/ACCEPTANCE REQUIREMENTS FOR SUPPLIES AND CONSUMABLES ....................................... 18

9 DATA MANAGEMENT ............................................................................................................. .................................... 19 9.1 Data Custody .............................................................................................................. .......................................... 19

10 DATA VALIDATION AND USABILITY .............................................................................................. ......................... 20
10.1 Data Review, Validation, and Certification ............................................................................... ........................... 20

10.1.1 Data Validation ........................................................................................................ .................................... 20 10.1.2 Data Collection ........................................................................................................ .................................... 20 10.1.3 Data Reduction ......................................................................................................... ................................... 20 10.2 Validation Methods ....................................................................................................... ...................................... 21

10.2.1 Data Review and Validation Requirements ................................................................................ ................. 21Hcn Sampling Plan_V7.Docx 

### iii 

# CONTENTS - Continued Page



## Tables
Table 1: Sensor Height on Towers ............................................................................................. ...................................... 2 Table 2: System Accuracies and Resolution .................................................................................... ................................ 3 Table 3: System Performance and Data Custody Forms ........................................................................... ...................... 5 Table 4: System Components ................................................................................................... ....................................... 6 Table 5: Sampling Frequency .................................................................................................. ...................................... 12 Table 6: Scheduled Sampling Activities ....................................................................................... .................................. 13 Table 7: Project Quality Control Checks ...................................................................................... .................................. 15
Table 8: Preventive Maintenance Schedule ..................................................................................... .............................. 16 Table 9: Calibration Equipment Testing ....................................................................................... .................................. 17
Table 10: Data Recorded on Site .............................................................................................. ..................................... 20



## Figures
Figure 1: HCN Sampling System Flow Diagram - Static Mode ..................................................................... ................... 9 Figure 2: HCN Sampling System Flow Diagram - Warm-Up Mode .................................................................... ........... 10 Figure 3: HCN Sampling System Flow Diagram - Sampling Mode Sorbent Tube 1 .................................................... .. 11



## Appendices
Appendix A: NIOSH Method 6010Hcn Sampling Plan_V7.Docx 

### 1 

## SECTION 1 

# PROJECT MANAGEMENT ELEMENTS

1.1 Sampling Purpose

This sampling plan is being developed to determine the levels of hydrogen cyanide (HCN) in ambient air at the fence line of a mine site. This plan describes the general HCN sampling equipment, collection methods, and data recording procedures. Separate site-specific plans will be submitted for individual mine sites where HCN monitoring will take place. The site-specific plans will be in accordance with this general plan unless otherwise noted, in which case the specific plan will take precedence.

There is currently no EPA method for measuring trace levels of HCN in ambient air. The method described in this monitoring plan was develope d using some elements of both EPA and NIOSH sampling and analytical guidelines. Meteorological parameters will be collected. In addition, an optional video surveillance system may be deployed to determine the operability of the sampler as well as identify any unusual conditions at the sampler.

The design of the system uses elements of U.S. EPA Quality Assurance Handbook of Air Pollution Measurement Systems Volume II as well as the NIOSH Manual of Analytical Methods, Method 6010. All meteorological parameters will be collected consistent with U.S. EPA Quality Assurance Handbook of Air Pollution Measurement System s Volume IV - Meteorological Measurements (EPA600/R94-038D), March 1995, and as provided in this plan.


# 1.2 System Description

The system will consist of a data logger connected to a low-flow pump which is connected through sorbent tubes to an ambient air inlet. The sorbent tubes will capture any HCN in the ambient air and will be sent to a certified lab for analysis. The sampling schedule will follow a 1- in-3 day calendar for a period of two months. During a run day, all parameters will be collected every two seconds and time-averaged into 15-minute values. The parameters collected are shown in Table 1. Wind speed, wind direction, ambient temperature, relative humidity, and barometric pressure are collected as well as flow rate through the sorbent tubes.

The measurement height of the inlet is two meters. The height of the wind instruments will be 3.5 meters. All other parameters are measured at 2 meters.Hcn Sampling Plan_V7.Docx 

### 2 Table 1: Sensor Height on Towers (meters above ground)



## Parameter Height Wind speed 3.5
Wind direction 3.5 Ambient temperature 2 Relative humidity 2 Barometric pressure 2 Sampler Flow 2Hcn Sampling Plan_V7.Docx 

### 3 

## SECTION 2 

# QUALITY OBJECTIVES AND CRITERIA FOR DATA MEASUREMENT

2.1 Data Quality Objectives and Criteria

The primary quality objectives are taken from EPA guidance where applicable. The following tables present the guidelines for each sensor as well as the relevant references for each.

Table 2: System Accuracies and Resolution

Parameter Sensor* Range Accuracy Standard Measurement
Resolution Reference

Wind direction R.M. Young 05305-AQ Range: 0 ° to 360 ° + 3 ° Accuracy:

+ 5 ° 1.0 ° EPA-454/4-87-007 Section 6.1.1, EPA-454/R-99-005, February 2000, Table 5-1 Wind speed R.M. Young 05305-AQ 0.4 to 45 m/s + 0.2 m/s Accuracy:

+ 0.25 m/s

up to speeds of 5

m/s and

+ 5% thereafter 0.1 m/s EPA-454/4-87-007 Section 6.1.1 EPA-454/R-99-005, February 2000, Table 5-1

Ambient temp. Campbell Scientific Model HMP45C -39.2 ° C to +60 ° C + 0.3 ° + 0.5 ° C 0.1 ° C EPA-454/4-87-007 Section 6.1.5 EPA-454/R-99-005, February 2000, Table 5-1 Relative humidity Campbell Scientific Model HMP45C 0.8 to 100% + 2% (0-90% RH) and

+ 3% (90- 100% RH) 1.5 ° C dew point temperature

error 1% EPA-454/4-87-007 Section 6.1.4 EPA-454/R-99-005, February 2000, Table 5-1
Barometric
pressure Vaisala PT101B -40 ° C to 60 ° C + 0.5 mb + 3 mb + 0.1 mb EPA-454/4-87-007 Section 6.1.7 EPA-454/R-99-005, February 2000, Table 5-1 Flow rate Pressure transducer N/A + 5% + 10% of observed 0.1 l/min N/A

* Or equivalent sensor.Hcn Sampling Plan_V7.Docx 

### 4 

## SECTION 3 

# SPECIAL TRAINING REQUIREMENTS/CERTIFICATION

The monitoring equipment should be operated unde r the guidance of the Project Technician. The Project Technician will receive training in the equipment operation. Any non-routine work on this system must be conducted by a qualified technician.Hcn Sampling Plan_V7.Docx 

### 5 

## SECTION 4 

# DOCUMENTATION OF RECORDS

All of the forms which will be used to document the system performance and data custody are
listed in Table 3.

Table 3: System Performance and Data Custody Forms



## Component Hard Copy or Electronic Copy Comments Site Check Form Hard Copy Include check of flow and meteorological sampling. Chain of Custody Form Hard Copy Record handling of sorbent tube through analytical process. Site-Specific Journal Record Hard Copy and Electronic Copy Record any anomalous

occurrences. Flow Audit Hard Copy and Electronic Copy Conduct at end of 2 month sampling period.



# 4.1 Data Reporting Package Format and Documentation Control

A report will be prepared and submitted to EPA within 30 days of the conclusion of the data collection program. The report will contain:

• A calculation of the percentage of valid data collected with an explanation of any instrument malfunction for each parameter,

• All valid hourly meteorological data,

• All valid flow data,

• All HCN concentrations determined by laboratory analysis,

• Copies of Site Check Forms,

• Copies of any calibrations and audits performed,

• Anecdotally conveyed no tes and anomalies, and

• Corrective actions taken (if any).
After the first four weeks of sampling, prelim inary data will be supplied to EPA after the analyses are received from the laboratory.Hcn Sampling Plan_V7.Docx 

### 6 

## SECTION 5 

# DATA GENERATION AND ACQUISITION

5.1 Sampling Process Design and Methods Requirements 5.1.1 Purpose
The monitoring requirements subject to EPA an d federal guidelines are strictly defined for meteorology but not for HCN. The equipment se lection and operation of the station is in accordance with available guidelines. In cases where an existing meteorological station at the mine meets all applicable guidelines, this station may be used in lieu of the meteorological equipment specified herein. The site-specific pl an submitted by each mine will address the proposed location of the meteorological monito ring station that will be used to provide meteorological data for the ambient fence line monitoring program.


# 5.1.2 Sampling Network Design
The monitoring system will consist of the following parts, or equivalent, as specified in the sitespecific plan. Each part will have a serial number and will be calibrated upon installation.

Table 4: System Components



## Item Manufacturer Model Name Enclosure Campbell Scientific ENC 12/14 3-meter tower Campbell Scientific 25G Wind sensor mount Campbe ll Scientific 019ALU Pyranometer mounting arm Campbell Scientific 015ARM Data logger CR3000 Campbell Scientific CR23X or CR10X Power supply with battery Ca mpbell Scientific PS12LA Solar panel Campbell Scientific MSX10R

Wind sensor R.M. Youn g Wind Monitor 05305-AQ Wind sensor cable R.M. Young Solar power system Kyocera Solar Electric System Temperature and relative humidity

sensor Campbell Scientific HMP45C

Barometric pressure sensor Vaisala PT101B

Flow meter Newark Electronics TE525

Flow meter Newark Electronics Pressure TransducerHcn Sampling Plan_V7.Docx 

### 7 

# 5.1.3 Equipment Description
The following section describes the air quality and meteorological instrumentation that will be used for the HCN monitoring program. The inst rumentation is selected consistent with the requirements of:

• U.S. EPA Quality Assurance Handbook of Air Pollution Measurement Systems Volume II, September 1997.

• NIOSH Manual of Analytical Methods, Method 6010, August 1994

.

• U.S. EPA Quality Assurance Handbook of Air Pollution Measurement Systems Volume IV - Meteorological Measurements (EPA-454/B-08-002), March 2008.
The data collection systems are designed to ex ceed the recommended quarterly data recovery rate of 90 percent for all meteorological parameters and 75 percent for HCN.


# 5.1.4 Data Logger
A Campbell Scientific, Inc. Model CR3000 data logger is used as the digital acquisition system for the stations. The data logger records the data every two seconds, computes 15-minute averages of each of the meteorological parameters, and stores the averages in its internal memory. The CR3000 has 4 mB of Flash Electrically Erasable Programmable Read Only Memory (EEPROM) for the operating system and user programs. It also has 512K of Static Random Access Memory (SRAM) used for storing approximately three months of data and running the program. It has a
16-bit micro-controller with 32-bit internal CPU ar chitecture. The resolution and accuracy of the analog inputs are 6.67 microvolts and ± 0.04%, respectively. The CR3000 is equipped with a solidstate storage module. The 15-minute averages are written to the CR3000's internal memory and to the external storage module. The storage module can store nearly six mo nths of data and will provide a backup of the data and the CR3000 prog ram in the unlikely event of a power loss. The data logger is designed to operate in temperatures from –25 ° C to 50 ° C.


# 5.1.5 Wind Speed
Wind speed is continuously measured using an R.M. Young Model 05305 sensor interfaced directly to the data logger. The wind speed sens or of the Model 05305 is a helicoid-shaped, fourblade propeller. Rotation of th e propeller produces an AC sine wave; the frequency is directly proportional to the wind speed. The AC signal is induced in a transducer coil by a six-pole magnet mounted on the propeller shaft. The coil is located on the non-rotating central portion of the main mounting assembly, eliminating the need for slip rings and brushes. Power for the sensor is supplied by the data logger. The Model 05305 has a range of 0.4 - 45 m/s, a starting threshold of 0.4 m/s, an accuracy of 0.2 m/s, and a distance constant of 2.1 meters.Hcn Sampling Plan_V7.Docx 

### 8 

# 5.1.6 Wind Direction
Wind direction is also continuously measured using an R.M. Young Model 05305 sensor interfaced directly to the data logger. The Model 05305 sensor provides a 1 ° to 360 ° format through the use of a precision potentiometer powered by the data logger. The potentiometer outputs a varying voltage proportional to the wind direction in degrees. The sensor is constructed from lightweight thermoplastic materials to give it a starting threshold of less than 0.5 m/s. The sensor has an accuracy of ±3 ° , a damping ratio of 0.45, and a delay distance of less
than 2 meters.


# 5.1.7 Temperature Sensor and Radiation Shield
The temperature measurements are continuously monitored using a Campbell Scientific HMP45C Platinum Resistance Temperature (PRT) detector. Temperature is measured by the data logger as a varying resistance across a platin um resistor that is proportional to the ambient temperature. The range of the sensor is –40°C to +60°C. The radiation shield for the temperature sensor prevents interference from solar radiatio n. The radiation error is less than 0.1°F.


# 5.1.8 Relative Humidity
Relative humidity is continuously measured using a Campbell Scientific Model HMP45C sensor.
The HMP45C contains a Vaisala HUMICAP TM 

## 180 capacitive relative humidity sensor. The HMP45C sensor is housed inside a non-aspirated shield. Relative humidity is measured by the data logger as an output voltage. The range of the sensor is from 0.8 to 100% (non-condensing) with an accuracy of ±2% when the humidity is less than 90%, and ±3% when the humidity is greater than 90%. The response time for th e relative humidity sensor is 15 seconds.



# 5.1.9 Barometric Pressure
Barometric pressure is measured every 15 minute s using a Vaisala PT101B sensor. The sensor is mounted inside the data logger enclosure. Barome tric pressure is measured by the data logger using Vaisala’s Barocap silicon capacitive pressu re sensor, which outputs a linear 0 to 2.5 VDC signal. The operating range of the sensor is –40 ° C to 60 ° C. The CS105 has a warm-up time of one second, an uncertainty of 0.15 millibar, and a linearity of 0.45 millibar.


# 5.1.10 HCN Sampling System
This instrument is designed to measure HCN at trace levels in ambient air. There is currently no
EPA certified method for this determination. Th e design combines elements of EPA air quality measuring guidelines along with NIOSH sampling protocols. The sampler consists of soda lime sorbent tubes (SKC part number 226-28) connected to a glass inlet. On the other side of the sorbent tubes is a low flow pump controlled by a data logger via a feedback loop with a pressure transducer. The flow is regulated by a critical orifice, and ambient meteorological parameters are collected to determine the exact volume of gas pass ed through the sorbent tubes. Data collection is in twenty-four hour increments. Upon complete exposure of a sorbent tube, it is sealed andHcn Sampling Plan_V7.Docx 

### 9 

## shipped to a certified laboratory for analysis in accordance with NIOSH Method 6010. The complete NIOSH Method 6010 is included as Appendix A.



## 5.1.10.1 Operating Principle
As discussed above, the HCN sampling system consis ts of an open-air inlet, sorbent tubes, and a pump which pulls air through the sorbent tubes at a rate of 1 liter per minute. The system is designed to hold two or more sorbent tubes, where each tube will collect a 24-hour sample. Based on the 1-in-3 day schedule, a site visit to change out the tubes will be required every 5-7 days (or longer if more than two tubes are design ed into the system). The total volume of air pulled through each sorbent tube is 1,440 liters. This exceeds the recommended total volume of NIOSH Method 6010 but is within the capture volu me of the sorbent tube and necessary to reach the required limits of detection.

A data logger turns the pump on and off and cont rols the solenoid valve according to the 1-in-3 day schedule. The solenoid valve opens and closes to allow air to pass through a sorbent tube only during a run day. The data logger al so records ambient barometric pressure and temperature to calculate the volume of air passed through the sorbent tube during the run day. Flow diagrams of the HCN sampling system, show ing the system in static mode, warm-up mode, and sampling mode, are provided in Figures 1 through 3.

Figure 1: HCN Sampling System Flow Diagram - Static Mode

INLET

SOLENOID VALVE



### SORBENT TUBE 1



### PRESSURE TRANSDUCER

PUMP

POWER RELAY 

### POWER 

### OUTLET DATA LOGGER

BAROMETRIC PRESSURE

TEMPERATURE 

### SORBENT TUBE 2



### CHECK VALVE 

### CALIBRATION VALVEHcn Sampling Plan_V7.Docx 

### 10 Figure 2: HCN Sampling System Flow Diagram - Warm-Up Mode

INLET

SOLENOID VALVE



### SORBENT TUBE 1



### PRESSURE TRANSDUCER

PUMP

POWER RELAY 

### POWER 

### OUTLET DATA LOGGER

BAROMETRIC PRESSURE

TEMPERATURE 

### SORBENT TUBE 2



### CHECK VALVE 

### CALIBRATION VALVEHcn Sampling Plan_V7.Docx 

### 11 Figure 3: HCN Sampling System Flow Diagram - Sampling Mode Sorbent Tube 1



## On a run day, at 15 minutes before the sampling commences, the data logger turns the pump on and switches the solenoid valve to allow air to flow around the sorbent tubes and through the pump. This gives the pump time to warm up and ensures that the air in the inlet is homogenous when the sampling begins. To initiate sampling, the data logger switches the solenoid valve to allow air to flow through the first sorbent tube an d the sampling begins. After 24 hours, the data logger closes the solenoid valve, stopping flow to the sorbent tube, and turns the pump off. On the next run day, after the warm-up period, to initiate sampling, the data logger switches the solenoid valve to allow air flow through the second sorbent tube. After 24 hours, the data logger closes the solenoid valve, stopping flow to the second sorbent tube. The tubes are replaced before the next run day and the sampling process repeats.

After the 24-hour sampling is complete, each sorbent tube is sealed and shipped to a certified laboratory where the HCN is extracted and anal yzed using spectroscopy. One in every five
sorbent tubes will be a field bl ank. The blank tubes will follow the same path as the sampled tubes, with the exception of being inserted into the sampling system. INLET

SOLENOID VALVE



### SORBENT TUBE 1



### PRESSURE TRANSDUCER

PUMP

POWER RELAY 

### POWER 

### OUTLET DATA LOGGER

BAROMETRIC PRESSURE

TEMPERATURE 

### SORBENT TUBE 2



### CHECK VALVE 

### CALIBRATION VALVEHcn Sampling Plan_V7.Docx 

### 12 

## The detection limit for this HCN sampling method is reported to be approximately 0.2 ppb 1



## , which is an order of magnitude less than the EPA reference concentration of 2.8 ppb.



# 5.1.11 Power and Data Transfer
Solar power is used to operate the equipment. The data logger is powered separately via a smaller solar cell to prevent total data and commu nications loss during periods of power loss. A cellular Internet modem is installed providing real-time satellite communications.


# 5.1.12 Meteorological Towers
A 10-foot Rohn 25G meteorological tower will be installed for the purpose of mounting the sensors. The tower will be grounded, and lightning protection will be installed on all signal lines.


# 5.2 Rationale for Design

The equipment has been selected based on its conformity to current EPA standards for meteorology and current NIOSH standards for HCN monitoring.



# 5.3 Scheduled Measurement Activities

The sampler pump will be activated on 1-in-3 da y schedule. During this period all parameters, with the exception of HCN concentration, will be collected every two seconds. This is
summarized in Table 5 and Table 6.

Table 5: Sampling Frequency



## Parameters Engineering
Units Sampling Rate Averaging Rate Number of Samples per
24-Hour Period Wind speed Meters/second Every 2 seconds Every 15 minutes 96 Wind direction Degrees Every 2 seconds Every 15 minutes 96
Ambient temperature and relative humidity Degrees Celsius and percent Every 2 seconds Every 15 minutes 96

Barometric
pressure Millibar Every 2 seconds Every 15 minutes 96

HCN sampler flow Liters/minute Every 2 Seconds Every 15 minutes 96
HCN concentration* Parts per billion Every 24 hours Every 24 hours 1

*HCN concentration can only be determined upon completion of laboratory analysis.

1 Kenneth G. Orloff et al., Hydrogen cyanide in ambient air near a gol d heap leach field: Measured vs. modeled concentrations, Atmospheric Environment, 2006, p. 3023.Hcn Sampling Plan_V7.Docx 

### 13 Table 6: Scheduled Sampling Activities



## Activity Frequency Required Personnel
Site Check Every 5-7 days Maintenance Technician Calibration At installation Project Technician
Flow Audit At close out Auditor



# 5.4 Measurement Syst em Failure Response

The primary mechanism for ensuring normal sy stem operation will be comprised of on-site checks conducted after the tubes have been sample d and before the next run day. The site check schedule will be every 5-7 days (or longer if more than two tubes are designed into the system). The Maintenance Technician is responsible for on-site checks and completion of Site Check Forms. Any issues that are detected during the site checks will be resolved as soon as possible.

If a run day sampling is missed or incomplete, a substitute 24-hour sampling can be used if it is completed before the next scheduled run day.Hcn Sampling Plan_V7.Docx 

### 14 

## SECTION 6 

# SAMPLING METHOD REQUIREMENTS

6.1 Sample Handling and Custody Requirements

A new sorbent tube will be inserted into the sampler system prior to midnight of a run day. After completion of the run, the sorbent tube will be removed and prepared for shipment to a certified lab. All sorbent tubes used for sampling will be tracked in a Chain of Custody Form.


# 6.2 Analytical Methods Requi rements and Breakthrough Check

The sample will be digested at the lab and a coloring agent will be added to make the cyanide spectroscopically active. UV/Vis spectroscopy will be employed to determine the cyanide concentration. The quantity of cyanide present will be combined with the known flow of the sample exposure to generate a 24-hour HCN sample concentration. The analysis will be
conducted in accordance with NIOSH Me thod 6010 (included as Appendix A).

As part of the HCN analysis, each tube will be checked for breakthrough. The sorbent tubes
consist of a front half and back half. Each half will be analyzed separately to determine the mass of cyanide. Any sample where the mass of cyanid e in the back half is greater than one-tenth of the mass of cyanide in the front half will be flagged indicating that breakthrough has occurred.


# 6.3 Quality Control Requirements

Quality control for the program will be affected through the use of site checks, post-installation calibration, and close out audits. Information pr ovided by each of these methods is documented
in the Table 7 below.Hcn Sampling Plan_V7.Docx 

### 15 Table 7: Project Quality Control Checks



## QC Check Information Provided Frequency Site Checks All information about the station status, which cannot be determined from the raw data. Additionally, it provides real-time data for comparison with hourly averages to insure that station is functioning within prescribed guidelines. Every 5-7 days

Calibrations Determines the serviceability, accuracy, and precision of the equipment operating on site. Sensors are tested over a full range of operating conditions to ensure that they are performing within prescribed guidelines. At installation

Flow Audit Determines the serviceability, accuracy, and precision of the equipment operating on site. Sensors are tested over a full range of operating conditions to ensure that they are performing within prescribed guidelines. At close outHcn Sampling Plan_V7.Docx 

### 16 

## SECTION 7 

# INSTRUMENT/EQUIPMENT TESTING, INSPECTION, AND MAINTENANCE REQUIREMENTS

The sensor/equipment maintenance schedule is based on the manufacturer’s guidelines. All routine maintenance tasks will be accomplishe d by the Project Technician. In addition, preventive maintenance tasks are summarized in Table 8.

Table 8: Preventive Maintenance Schedule



## Parameter Sensor Replacement Frequency
Wind speed and direction R.M. Young 05305-AQ Every 2 years.
Temperature/relative humidity Campbe ll Scientific HMP45C Every 2 years.
Barometric pressure Vaisala PT101B Every 2 years. Sampling pump SKC Low Flow Pump to be refurbished annually.

*Due to the duration of the sampling program, it is anticipated that preventive maintenance will not be needed.



# 7.1 General Procedures

The Project Technician will review the Site Chec k Forms and compare them to the 15-minute data
averages to ensure proper syst em operation and data transfer.


# 7.2 Instrument Calibration and Frequency

The following section outlines the preventive ma intenance/recalibration of the equipment used to test the performance of the on-site systems.


# 7.2.1 Calibration Eq uipment Maintenance
The identity, frequency, and governing standard for all calibration equipment can be found in
Table 9.Hcn Sampling Plan_V7.Docx 

### 17 Table 9: Calibration Equipment Testing



## Parameter Calibration Equipment Calibration Frequency Reference Wind speed Anemometer Drive 200 to 15,000 RPM Biannually EPA 600/R-94/038D, Section 4.2.2 Wind direction Degree Wheel N/A EPA 600/R-94/038D, Section 4.2.2 Temperature Temperature Standard Annually EPA 600/R-94/038D, Section 4.3.2 Barometric pressure Altimeter N/A EPA 600/R-94/038D, Section 4.6 Relative humidity Collocated HMP45C Biannually EPA 600/R-94/038D, Section 4.6 Data logger Voltmeter Annually EPA 600/R-94/038D, Section 4.1.4.1 Flow Flow Meter Annually N/A

The equipment supplier will be required to maintain calibration equipment certifications in hard

copy.



# 7.2.2 Calibration Reco rds and Traceability
Calibration Forms are completed and maintained by project personnel. All Calibration Forms indicate the sensor calibrated, its serial numb er, the date calibrated, and any other pertinent information/anomalies.Hcn Sampling Plan_V7.Docx 

### 18 

## SECTION 8 

# INSPECTION/ACCEPTANCE REQUIREMENTS FOR SUPPLIES AND CONSUMABLES

The only consumable used in this process is the sorbent tubes. All tubes will be inspected upon receipt. Any tubes which show signs of physical damage will be discarded. Documentation sent with the maintenance items are kept on file as they apply to each sensor and its serial number.Hcn Sampling Plan_V7.Docx 

### 19 

## SECTION 9 

# DATA MANAGEMENT

The data will be collected and stored in the da ta logger and backed up in the on-site storage module. The data can be automatically or manually transferred to the user’s database. The data will then be quality controlled/quality assura nce checked (QA/QC’d) and stored on a server.


# 9.1 Data Custody

Data retrieval, quality control, and processing will be documented. Site Check Forms and all other program documentation will be archived. Additionally, a journal will be kept to record any
anomalous occurrences.Hcn Sampling Plan_V7.Docx 

### 20 

## SECTION 10 

# DATA VALIDATION AND USABILITY

10.1 Data Review, Validation, and Certification
10.1.1 Data Validation
The data will be reviewed, quality controlled/quality assurance checked (QA/QC’d), and validated in accordance with EPA guidelines.



# 10.1.2 Data Collection
Data received from the site will consist of 15-minute averages for all parameters. A complete list of parameters from the site can be found in Table 10.

Table 10: Data Recorded on Site



## Parameter Units Frequency Array ID N/A Every 15 minutes Year -- Every 15 minutes Day Julian Day Every 15 minutes Time Hour/Minute Every 15 minutes Wind speed Meters/Second Every 15 minutes Wind direction Degrees from Every 15 minutes
Wind direction standard devi ation None Every 15 minutes Barometric pressure Millibar Every 15 minutes Relative humidity Percent Every 15 minutes Ambient temperature Degrees Celsius Every 15 minutes Data logger battery voltage DCV Every 15 minutes SIN wind direction None Every 15 minutes COSINE wind direction None Every 15 minutes Flow l/min. Every 15 minutes



# 10.1.3 Data Reduction
On-site data is collected every two seconds and pl aced into temporary storage. Every 15 minutes the data is reduced and stored in the ring memory of the data logger. The wind speed, temperature, relative humidity, barometric pressure, and flow data are reduced as scalar averages using the equation below.


# ∑

= N

i 

## u N u

1 

## 1

The wind direction data is reduced as a unit vector according to the following equations.Hcn Sampling Plan_V7.Docx 

### 21 

# ∑

= N

i S 

## Sin N V

1 

## 1 θ



# ∑

= N

i C 

## Cos N V

1 

## 1 θ



# X V V ArcTan

C S 

# + ⎟ ⎟ ⎠ ⎞ ⎜ ⎜ ⎝ ⎛

= θ

If Vc < 0 then X = +180 If Vs < 0 then X = +360 If Vs > 0 then X = +0

The wind direction deviation is reduced using the Yamartino algorithm found below. 

# ( ) ( ) 

# [ ] 3 

## 1547

. 0 1 1 ε ε θ σ + = ArcSin

where, 

# () () 

# ( ) 

# [ ] 2 1 2 2 

## 1 C S 

## V V +

− = ε

and Vs and Vc are as defined above.

After the 15-minute data has been downloaded, it is processed into one-hour averages using the same equations listed above.



# 10.2 Validation Methods
10.2.1 Data Review and Validation Requirements
The data review and validation requirements follow the protocols outlined in Section 5 of this monitoring plan. The validation is accomplished by using quality control standards based on federal and manufacturer’s guidelines as well as expected sampler performance. If a quality control standard is not met, the data will be flagged initially, and the causes immediately investigated. All data, which is found to be invali d, will be removed from the data set. All data, which is subsequently proven to be valid, will be processed for inclusion in the reports.

# APPENDIX A 

# NIOSH Method 6010

## HYDROGEN CYANIDE 6010



## HCN MW: 27.03 CAS: 74-90-8 RTECS: MW6825000

METHOD: 6010, Issue 2 EVALUATION: FULL Issue 1: 15 May 1989 Issue 2: 15 August 1994

OSHA : 10 ppm (skin) NIOSH: STEL 4.7 ppm ACGIH: C 10 ppm (skin)

(1 ppm = 1.105 mg/m 3 @ NTP) PROPERTIES: gas; BP 26 °C; vapor density 0.93 (air = 1.00); d(liq) 0.69 g/mL @ 20 °C; VP 82.7 kPa (620 mm Hg) @ 20 °C; explosive range 5 to 40% v/v in air

SYNONYMS: hydrocyanic acid, prussic acid, formonitrile

SAMPLING

SAMPLER: SOLID SORBENT TUBE

(soda lime, 600 mg/200 mg)

FLOW RATE: 0.05 to 0.2 L/min

VOL-MIN: 2 L @ 5 ppm
-MAX: 90 L

SHIPMENT: routine

SAMPLE STABILITY: at least 2 weeks @ 25 °C [1]

BLANKS: 2 to 10 field blanks per set MEASUREMENT

TECHNIQUE: SPECTROPHOTOMETRY,

VISIBLE ABSORPTION

ANALYTE: cyanide ion complex

DESORPTION: 10 mL deionized water; stand 60 min

COLOR DEVELOPMENT: N-chlorosuccinimide/ succinimide oxidizing agent and barbituric acid/pyridine coupling agent; absorption @ 580 nm in 1-cm cuvette

CALIBRATION: standard solutions of KCN in 0.1 N NaOH

RANGE: 10 to 300 μg CN - per sample [1]

ESTIMATED LOD: 1 μg CN - per sample [1]

PRECISION ( S r ): 0.041 @ 10 to 50 mg per sample [1] ACCURACY

RANGE STUDIED: 2 to 15 mg/m 3 [1] (3-L samples)

BIAS: Not significant

OVERALL PRECISION ( S ˆ rT ): 0.076 [1]

ACCURACY: ± 15.0%

APPLICABILITY: The working range is 0.3 to 235 ppm (3 to 260 mg/m 3 ) for a 3-L air sample. This method is applicable to STEL measurements. Particulate cyanides are trapped by the initial glass fiber membrane disk. This method is more sensitive a nd subject to fewer interferences than NIOSH Method 7904, which uses ion specific electrode analysis. The method was used t o determine HCN in firefighting environments [2].

INTERFERENCES: A high concentration of hydrogen sulfide gives a negative interference.

OTHER METHODS: This is based on the method of Lambert, et al. [3]. NIOSH Method 7904 uses an ion specific electrode for measurement. The method has been adapted for use with a Technicon Autoanalyzer [4].

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94

### HYDROGEN CYANIDE: METHOD 6010, Issue 2, dated 15 August 1994 - Page 2 of 5

SAMPLING: REAGENTS:

1. Potassium cyanide*, reagent grade. 2. Succinimide, reagent grade. 3. N-Chlorosuccinimide, reagent grade. 4. Barbituric acid, reagent grade. 5. Pyridine, spectrophotometric quality. 6. Phenolphthalein, 1% (w/v) in ethanol or methanol, reagent grade. 7. Hydrochloric acid, concentrated, reagent grade. 8. Sodium hydroxide (NaOH), reagent grade.* 9. Sodium lime (CaO + 5-20% NaOH), reagent grade (Aldrich #26,643-4 or equivalent). Crush and sieve to 10/35 mesh. Store in capped container.* 10. Water deionized-distilled. 11. Sodium hydroxide solution, 0.1 N .* 12. Calibration stock solution. 1 mg /mL CN -



### . Dissolve 0.125 g KCN in 0.1 N NaOH in a 50- mL volumetric flask. Dilute to mark with 0.1 N NaOH. Standardize by titration with standard AgNO 3 

### solution (see APPENDIX). 13. Hydrochloric acid solution, 0.15 N

. 14. N-Chlorosuccinimide/succinimide oxidizing reagent. Dissolve 10.0 g succinimide in about 200 mL distilled water. Add 1.00 g Nchlorosuccinimide. Stir to dissolve. Adjust volume to 1 liter with distilled water. Stable 6 months when refrigerated. 15. Barbituric acid/Pyridine reagent. Add about 30 mL distilled water to 6.0 g barbituric acid in a 100-mL Erlenmeyer flask. Slowly add 30 mL pyridine with stirring. Adjust the volume to 100 mL with water. Stable 2 months when refrigerated. EQUIPMENT:

1. Sampler, glass tube, 9 cm long, 7-mm OD, 5-mm ID, with plastic caps, containing two sections (front = 600 mg; back = 200 mg) granular soda lime 10/35 mesh, separated and contained with silanized glass wool plugs, with a 5-mm diameter glass fiber filter disk placed before the plug on inlet side. Tubes are commerically available. (SKC, Inc. 226-28 or equivalent.) 2. Spectrophotometer, visible, 580 nm, with cuvettes, 1-cm light path. 3. Personal sampling pump, 0.05 to 0.2 L/min, with flexible connecting tubing. 4. Pipets, volumetric 0.1-, 0.5-, 1.0-, 2.0-, 10.0-mL. 5. Vials, glass or plastic, 15-mL with PTFE-lined
caps. 6. Flasks, volumetric, 25-, 50-, 100-, 1000-mL, with stoppers. 7. Pipets, transfer, disposable. 8. Syringes, 10-μL, readable to 0.1 μL. 9. Flask, Erlenmeyer, 100-mL. 10. Syringes, 10-mL, polyethylene with luer tip. 11. Filter cassette, with membrane filter, 13-mm diameter, 0.45-μm pore size, with luer fitting.

* See SPECIAL PRECAUTIONS

SPECIAL PRECAUTIONS: HCN gas and cyanide particulates are highly toxic and may be fatal if swallowed, inhaled, or absorbed through the skin [5]. Soda lime and NaOH are very caustic [5]. Use gloves and a fume hood for handling these chemicals. 1. Calibrate each personal sampling pump with a representative sampler in line. 2. Break ends of sampler immediately before sampling. Attach sampler to personal sampling pump with flexible tubing. 3. Sample at an accurately known flow rate between 0.05 and 0.2 L/min for a total sample size of 0.6 to 90 L. 4. Cap tube. Pack securely for shipment.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94

### HYDROGEN CYANIDE: METHOD 6010, Issue 2, dated 15 August 1994 - Page 3 of 5

SAMPLE PREPARATION:

5. Score each sampler with a file. Break sampler at score line. 6. Transfer front and back sorbent sections to separate vials. Discard glass wool plugs separating and retaining sorbent sections. NOTE: An estimate of particulate cyanide may be obtained by analyzing the initial glass fiber filter disk as follows; however, no evaluation data are available for particulate cyanides determined in this manner. (i) Transfer the glass wool plug at the tube inlet and the glass fiber filter disk immediately behind it to a third vial. (ii) Add 10.0 mL 0.1 N NaOH to each vial. (iii) Proceed with step 8. 7. Add 10.0 mL deionized-distilled water to each vial containing a sorbent section. Cap each vial. 8. Allow to stand 60 minutes, with occasional agitation. Transfer to a 10-mL plastic syringe fitted with an in-line 0.45-μm filter. Collect the filtrate in a clean vial.

CALIBRATION AND QUALITY CONTROL:

9. Calibrate daily with at least six working standards over the range 1 to 300 μg CN - 

### per sample.

a. Prepare a working standard solution, 1.00 μg /mL.CN - 

### , by diluting 100 μL of calibration stock solution to 100 mL with 0.1 N NaOH. b. Pipet 0.5-, 1.00-, 1.50-, 2.00- and 2.50-mL of the working standard solution into 25-mL volumetric flasks to make 0.50-, 1.00-, 1.50-, 2.00- and 2.50- μg CN - 

### standards.

c. Analyze together with field samples and blanks (steps 12 through 19). d. Prepare calibration graph (absorbance vs. μg CN - 

### ). 10. Determine desorption efficiency (DE) at least once for each lot of soda lime used for sampling. Prepare at least three tubes at each of five levels plus three media blanks.

a. Remove and discard back sorbent section of a blank sampler. b. Inject a known amount of calibration stock solution directly onto the soda lime with a microliter syringe.

c. Cap, and allow to stand overnight. d. Desorb (steps 5 through 8) and analyze together with working standards and blanks (steps 12 through 19).

e. Prepare a graph of DE vs. μg CN - 

### recovered. 11. Analyze three quality control blind spikes and three analyst spikes to ensure that the calibration graph and DE graph are in control.

MEASUREMENT:

12. Set spectrophotometer according to manufacturer's recommendations and to conditions on p. 6010-1. 13. Pipet a sample aliquot estimated to contain 0.5 to 2.5 μg CN - 

### into a 25-mL volumetric flask. Alternately, to cover an unknown sample concentration range, pipet 0.5-, 1.00-, and 3.00-mL aliquots into separate 25-mL vol. flasks for each field sample. Larger or smaller aliquots may be taken, based on prior knowledge of expected analyte level. 14. Pipet 0.5 mL 0.1 N NaOH into a 25-mL volumetric flask for reagent blank. 15. Add one drop phenolphthalein solution to each standard or sample. NOTE: Add a little deionized-distilled water to increase volume for easier mixing. All solutions should be alkaline (pink) at this point. 16. Starting with the reagent blank, add dropwise 0.15 N HCl, with mixing, until pink color just disappears. CAUTION: HCN may be produced. Work in hood. Immediately add 1.0 mL N-chlorosuccinimide/succinimide oxidizing reagent. Mix and let stand.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94

### HYDROGEN CYANIDE: METHOD 6010, Issue 2, dated 15 August 1994 - Page 4 of 5

NOTE 1: To avoid possible loss of HCN, add the oxidizing agent before proceeding to the

next sample. NOTE 2: Do not prepare more samples than can be analyzed within the 30-minute maximum

time for color development. 17. After at least 5 min. standing (but not longer than 15 min), starting with the reagent blank, add 1.0-mL barbituric acid-pyridine coupling reagent. Mix. 18. Adjust sample volume to 25 mL with deionized-distilled water and allow to stand at least 12 min (but not longer than 30 min) for color development. 19. Read absorbance at 580 nm in a 1-cm light path cuvette on a spectrophotometer. If sample absorbance is outside the range of the calibration standards, take an aliquot, re-analyze (steps 12 through 19), and apply the appropriate aliquot factor in calculations.

CALCULATIONS:

20. Calculate the mass, μg, of CN - 

### in aliquot analyzed. Apply the appropriate aliquot factor to calculate the mass, μg, of CN - 

### in the original 10-mL solution. 21. Determine the mass, μg CN - 

### (corrected for DE), found in the sample front (W f 

### ) and back (W b 

### ) sorbent sections and in the average media blank front (B f 

### ) and back (B b 

### ) sorbent sections. If W b 

### > W f 

### /10, report breakthrough and possible sample loss. 22. Calculate concentration, C, of HCN in the air volume sampled, V(L).

where 1.039 = conversion factor, CN - 

### to HCN

EVALUATION OF METHOD:

The method was evaluated by sampling the test atmospheres of HCN generated from a compressed mixture of HCN in nitrogen [1]. The range of HCN concentration was equivalent to 2 to 15 mg/m 3 

### for a 3-L air sample. Twenty-two samples collected at 0.2 L/min for 15 minutes indicated overall precision S ˆ rT 

### of 0.076 with nearly 100% recovery. Breakthrough occurred after 40 minutes of sampling at the flow rate of 0.2 L/min at an HCN concentration of 148 mg/m 3 

### . Sample tubes spiked with solutions of KCN and analyzed after storage, indicated that the samples of cyanide ions were stable on the tube for at least 2 weeks. Analysis of 22 tubes which were spiked with KCN standard solutions in the range 10 to 50 μg indicated a recovery of nearly 100% with a pooled precision of 0.041. Desorption efficiency may be poor below 10 μg CN - 

### [6].

REFERENCES:

[1] Williamson, George. "Method Development Protocol and Backup Data Report on Hydrogen Cyanide" Internal NIOSH/MRSB Report, Unpubl. NIOSH (1988). [2] Williamson, George. "Analysis of Air Samples on Project 166 (Firesmoke) on HCN; Sequence NIOSH/MRSB-6366A, Unpubl. NIOSH, (1988). [3] Lambert, J. L., Ramasamy, J., and J. V. Paukstelis, "Stable Reagents for the Colorimetric Determination of Cyanide by Modified Konig Reactions," Analyt. Chem.

, 47 , 916-918 (1975). [4] DataChem Laboratories, NIOSH Sequence #6837-K (unpublished, March 21, 1990). [5] NIOSH/OSHA Occupational Health Guidelines for Chemical Hazards, U.S. Department of Health and Human Services. Publ. (NIOSH) 81-123 (1981), available as stock #PB 83-154609 form NTIS, Springfield, VA 22161. [6] DataChem Laboratories, User Check, NIOSH Sequence #6837-J (unpublished, March 19, 1990).

METHOD WRITTEN BY: George Williamson, NIOSH/DPSE.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94

### HYDROGEN CYANIDE: METHOD 6010, Issue 2, dated 15 August 1994 - Page 5 of 5

APPENDIX: STANDARDIZATION OF CALIBRATION STOCK SOLUTION

Titrate an aliquot of the cyanide standard stock solution (Reagent 12) with standard silver nitrate (AgNO 3 

### ) solution. The end point is the first formation of a white precipitate, Ag[Ag(CN) 2 

### ]. Calculate the cyanide concentration with the following equation:

M
c 

### = 52.04 V
a 

### (M
a 

### /V
c 

### )

Where M
c



### = cyanide concentration (mg/mL) V
a 

### = volume (mL) of standard silver nitrate solution M
a 

### = concentration (moles/L) of standard silver nitrate solution V
c 

### = volume (mL) of calibration stock solution titrated

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94