## REVIEW OF

ARIZONA DEPARTMENT OF ENVIRONMENTAL QUALITY’S

TECHNICAL SUPPORT DOCUMENT

FOR THE DEPARTMENT’S

PROPOSED BOUNDARY RECOMMENDATION

FOR THE 2008 REVISION OF THE NAAQS FOR LEAD

Prepared for:



### ASARCO LLC

5285 E AST 

### W ILLIAMS 

### C IRCLE



### , S UITE 

### 2000
T UCSON



### , A RIZONA 

### 85711-7711

Prepared By:



### Z EPHYR 

### E NVIRONMENTAL 

### C ORPORATION


### 10420 L ITTLE 

### P ATUXENT 

### P ARKWAY



### , S UITE 

### 320
C OLUMBIA



### , M ARYLAND 

### 21044

N OVEMBER 

### 10, 2009R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

Z EPHYR E NVIRONMENTAL C ORPORATION 1 

## CONTENTS

EXECUTIVE SUMMARY ............................................................................................................. . 3

1.0 BACKGROUND ................................................................................................................... 5

2.0 ISSUES IDENTIFIED ........................................................................................................... 7

2.1 E XCEPTIONAL 

### E VENTS 

### ................................................................................................. 7

2.1.1 Dates Deemed to Have Exceptional Wind Speeds ...................................... 10

2.1.2 Impact of Removing Exceptional Events ...................................................... 12

2.2 S UITABILITY OF 

### M ONITOR 

### L OCATION 

### .......................................................................... 13

2.3 Q UALITY 

### A SSURANCE 

### ................................................................................................ 15

2.4 D ATA 

### C OMPLETENESS 

### (V ALIDATION OF 

### T HREE 

### -M ONTH 

### M EANS 

### ) .................................. 16

2.5 U NCERTAINTY 

### R EGARDING 

### D ESIGN 

### V ALUE 

### ................................................................. 21R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

Z EPHYR E NVIRONMENTAL C ORPORATION 2 

## APPENDICES

Appendix A Hayden Air Quality Monitoring Resu lts, Received from EPA on September 23,

2009R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

Z EPHYR E NVIRONMENTAL C ORPORATION 3



## EXECUTIVE SUMMARY

In a September 28, 2009 document entitled “Arizona Air Quality Designations Technical Support Document Boundary Recommendation for the 2008 Revision to the National Ambient Air Quality Standard for Lead” (TSD), the Arizona Department of Environmental Quality (ADEQ) made a proposal that the Governor should recommend to the U.S. Environmental Protection Agency (EPA) that portions of Gila and Pinal Counties (hereinafter the Hayden area) be designated as being in nonattainment of the National Ambient Air Quality Standard (NAAQS) for lead. The ADEQ’s proposal is based on air monitoring data collected in the Hayden area as part of a remedial investigation in a CERCLA proc eeding between the EPA, ADEQ and ASARCO LLC (Asarco).

Asarco retained Zephyr Environmental Corporat ion (Zephyr) to review the TSD underlying the ADEQ’s proposal.

Zephyr’s review identified the following issues:

• Some of the monitored lead values relied upon in the TSD are associated with “exceptional events” under 40 CFR Part 50 and ADEQ guidance and should therefore not be counted toward determining whether the Hayden area is in nonattainment of the NAAQS for lead. When these “exceptional events” values are excluded there are no
monitored values above the NAAQS.

• The Hayden monitor is located on top of the Town of Hayden maintenance building. Given the soldering/welding activities and vehicle traffic that take place at the maintenance yard, the potential exists for contamination of the samples obtained using

the monitor.

• The Quality Assurance (QA) plan governing the Hayden monitor and the results of the various tests and calibrations required under the quality assurance rules governing ambient air monitors were not available at the time of Zephyr’s review. As of the date of the TSD, the ADEQ had not reviewed information on the required quality assurance checks of the Hayden monitor, and it remains uncertain whether such checks occurred. This calls into question the validity of the data generated using the monitor.

• In support of the ADEQ’s proposal, the TSD (at Table 4-1) compares 3-month means to the NAAQS. However, the TSD does not demonstrate the ADEQ validated the 3-month means according to 40 CFR Part 50, Appendix R Section 4(c) procedures. If these procedures were followed, it would be found that all the 3-month means above the lead NAAQS do not meet the specific 75% data completeness requirement.

• The Design Value (i.e., the single mean concentration that is required under the rules to be compared to the NAAQS to demonstrate attainment or nonattainment) was not clearly identified or adequately discussed in the TSD.

Based on these findings, the proposed nonattainment designation for the Hayden area is unwarranted. In order to make a defensible proposal of a nonattainment designation, more representative, quality controlled and quality assured data are needed, and the data need to beR EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

Z EPHYR E NVIRONMENTAL C ORPORATION 4 

### evaluated properly under the rules at 40 CFR Part 50, Appendix R and ADEQ guidance, including the effect of exceptional events and data validation.R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

Z EPHYR E NVIRONMENTAL C ORPORATION 5 

## 1.0 BACKGROUND

ASARCO LLC (Asarco) conducts beneficiation and smelting of copper ores at its Ray ComplexHayden Operations in Hayden, Arizona, approx imately 80 miles east-southeast of Phoenix and 60 miles north of Tucson. In April 2008 a CERCLA Administrative Settlement Agreement and Order on Consent (Settlement Agreement) was entered into by the U.S. Environmental Protection Agency (EPA), the Arizona Department of Environmental Quality (ADEQ) and Asarco. One of the stipulations of the Settlement Agreement was that Asarco conduct a Remedial Investigation/Feasibility Study (RI/FS), which among other things called for the continuation of air quality monitoring that the EPA had already begun in the Hayden area. That monitoring addressed several air pollutants, one of which was lead.

On November 12, 2008 the EPA revised the National Ambient Air Quality Standard (NAAQS) for
lead. 1 

### The revised NAAQS was established at 0.15 μg/m 3 

### on a rolling three-month averaging period.

On September 28, 2009 the ADEQ completed a Technical Support Document 2 

### (TSD) in which it proposed that the Governor recommend to the EPA a designation of portions of Gila and Pinal Counties as being in nonattainment of the revised NAAQS for lead. The proposed nonattainment area is presented in Figure 1-1.

Asarco retained Zephyr Environmental Corporation (Zephyr) to review the ADEQ’s proposal. In its review, Zephyr evaluated both the technical and the regulatory merits of the ADEQ’s proposal.

This report documents Zephyr’s findings.

1 73 Fed. Reg. 66964.

2 “Arizona Air Quality Designations Technical Supp ort Document Boundary Recommendation for the 2008 Revision to the National Ambient Air Quality Standard for Lead,” Air Quality Division, ADEQ.R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

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### Figure 1-1 ADEQ Proposed Lead Nonattainment Area for Hayden, Arizona (taken from ADEQ’s TSD)R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

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## 2.0 ISSUES IDENTIFIED

Zephyr identified several issues which, to varying degrees, call into question the ADEQ’s proposal of the Hayden area as nonattainment for lead. These issues are elaborated upon
below.



## 2.1 E XCEPTIONAL 

## E VENTS

40 CFR Part 50 defines an exceptional event as “an event that affects air quality, is not reasonably controllable or preventable, is an event caused by human activity that is unlikely to recur at a particular location or a natural event...” 40 CFR 50.14(c)(3)(iv) presents the criteria that must be met for an event to be deemed exceptional under this rule:

• The exceptional event is a cause of the monitored value,

• The event in question is beyond normal historical fluctuations, and

• There would not have been an exceedance of the NAAQS without this event.

Should a monitored value be excluded for being associated with an exceptional event, 40 CFR 50.14(b) stipulates that those excluded data are not to be included in a determination of an exceedance of a NAAQS.

On October 15, 2009, the ADEQ issued a report entitled “The Impact of Exceptional
Events ‘Unusual Winds’ on PM 10 

### Concentrations in Arizona” 3 

### that provides guidance as to how to determine what constitutes an exceptional event in terms of winds. The report considered historical environmental and meteorological data, including data from Hayden. One of the conclusions of the report was as follows:

For exceptional events purposes, “unusual winds” can be defined as any wind that has the ability to create wind blown dust. Literature and data from monitors indicate that the phenomenon of blowing dust can occur over a broad range, but generally is associated with hourly averaged wind speeds that are above 10 miles per hour, which are commonly associated with wind gusts over 20 miles per hour.

As a first step Zephyr reviewed both lead concentrations and wind speeds for the entire year of 2008 to identify any potential relationship between the two. As shown in Figure 2-1, there clearly is a correlation between three-mont h average lead concentrations observed at the

3 “The Impact of Exceptional Events ‘Unusual Winds’ on PM 10 Concentrations in Arizona”, ADEQ Air Quality Division (October 15, 2009). 

## Recent ADEQ guidance supports the

determination that three days in late

2008 are “exceptional events.” When they are removed, the revised Design

Concentration is below the NAAQS.R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

Z EPHYR E NVIRONMENTAL C ORPORATION 8 

### Hayden monitor and three-month average wind speeds observed at the same monitor. Both the three-month average lead concentrations and wind speeds are at their lowest in the spring, then attain an intermediate maximum in June, and then reach their greatest values in the late fall.

Figure 2-1 Average Lead Concentrations and Wind Speed Observed at Hayden Monitor, 2008

A single short-term (e.g., an hour) concentration at a monitor that is extraordinarily high can lead to a high 24-hr concentration (even with the rest of the 24-hr period having fairly low impacts). This is illustrated, by way of example, by the data in Figure 2-2, taken from a continuous PM 10 

### monitor located at the University of Texas at El Paso (EPA ID # 481410037). 0.000 0.050 0.100 0.150 0.200PbConcentration(ug/m3) 

# Rolling 3

‐ Month Lead Averages Hayden Monitor, 2008

4.0 4.5 5.0 5.5 6.0WindSpeed(mph) 

# Rolling 3

‐ Month Average Wspd Hayden Monitor, 2008R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

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### Figure 2-2 Example of One Hour of Elevated Concentration Leading to High 24-hr Concentration

As shown in the figure above, the vast majority of the hourly PM 10 

### concentrations on this day are below the 24-hr NAAQS of 150 μg/m 3 

### . However, the overall daily average is radically affected by several very high individual hourly monitored values (although not indicated on this plot, the high concentrations were associated with winds in excess of 10 mph), ultimately leading to a 24-hr concentration greater than the NAAQS.

Therefore, a day that has a single hourly av erage wind speed of 10 mph or greater is a candidate for being an exceptional event (note that this discussion focuses on average winds, not a wind gust which would be higher than the hourly average) in the context of 40 CFR 50.14(c)(3)(iv). However, for the sake of c onservatism Zephyr decided to focus only on days with more than one hour of average wind speeds greater than 10 mph.

An examination of the meteorological data gathered at Hayden during the months of July through November, inclusive, in 2008 (the months whose data are associated with all calculated lead NAAQS exceedances as presented in the TSD) revealed that only three days had more than one average hourly wind speed greater than 10 mph. Details on these days are presented below (note that the plots show both average hourly winds as well as average 30-minute winds).R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

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### 2.1.1 Dates Deemed to Have Exceptional Wind Speeds

2.1.1.1 August 5, 2008

On August 5, 2008 there were two hourly average wind speeds at the Hayden monitor in excess of 10 mph. These two wind speeds occurred at 7:00 PM and 8:00 PM (with the 6:00 PM wind speed being 9.6 mph). Therefore, this day experienced a concentrated period of exceptionally high winds in the evening. More information concerning the winds of that day is presented in the table to the right.

Figure 2-3 Hayden Monitor Average 30-Minute and Hourly Wind Speeds August 5, 2008 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.01:00AM2:00AM3:00AM4:00AM5:00AM6:00AM7:00AM8:00AM9:00AM10:00AM11:00AM12:00PM1:00PM2:00PM3:00PM4:00PM5:00PM6:00PM7:00PM8:00PM9:00PM10:00PM11:00PM12:00AMWindSpeed(mph) 

# Wind Speed, Hayden, Arizona August 5, 2008

30

‐ min Wspd

Hrly Wspd August 5, 2008 Wind Speed

Information

Maximum 30-min

Wind Speed 18.6 mph

Maximum Hourly

Wind Speed 16.1 mphR EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

Z EPHYR E NVIRONMENTAL C ORPORATION 11 

### 2.1.1.2 September 30, 2008

On September 30, 2008 there were five hourly average wind speeds at the Hayden monitor in excess of 10 mph. These five wind speeds occurred between 6:00 AM and 11:00 AM, with the 8:00 AM wind speed being just below 10 mph. Therefore, this day experienced a concentrated period of exceptionally high winds in the morning. More information concerning the winds of that day is presented in the table to the right.

Figure 2-4 Hayden Monitor Average 30-Minute and Hourly Wind Speeds September 30, 2008



### 2.1.1.3 October 22, 2008

On October 22, 2008 there were ten hourly average wind speeds at the Hayden monitor in excess of 10 mph. Eight of these wind speeds occurred between 10:00 AM and 5:00 PM (note the 9:00 AM wind speed was 9.9 mph), with the other two occurring at 11:00 PM and midnight. Therefore, this day experienced a concentrated period of exceptionally high winds throughout a substantial portion of the day. More information concerning the winds of that day is presented in the table to the right. 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.01:00AM2:00AM3:00AM4:00AM5:00AM6:00AM7:00AM8:00AM9:00AM10:00AM11:00AM12:00PM1:00PM2:00PM3:00PM4:00PM5:00PM6:00PM7:00PM8:00PM9:00PM10:00PM11:00PM12:00AMWindSpeed(mph) 

# Wind Speed, Hayden, Arizona September 30, 2008

30

‐ min Wspd

Hrly Wspd September 30, 2008 Wind
Speed Information

Maximum 30-min

Wind Speed 12.9 mph

Maximum Hourly

Wind Speed 12.3 mph

October 22, 2008 Wind Speed

Information

Maximum 30-min

Wind Speed 18.5 mph

Maximum Hourly

Wind Speed 18.1 mphR EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

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### Figure 2-5 Hayden Monitor Average 30-Minute and Hourly Wind Speeds October 22, 2008



### 2.1.2 Impact of Removing Exceptional Events

As mentioned above, 40 CFR 50.14(b) states that if a monitored value is deemed to be caused by an exceptional event that that value is not to be included in the determination of an exceedance of the NAAQS. Accordingly, the three NAAQS exceedances identified in Table 4-1 of the ADEQ’s TSD were recalculated without the inclusion of data from the three days identified above. The revised results are presented below. 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.01:00AM2:00AM3:00AM4:00AM5:00AM6:00AM7:00AM8:00AM9:00AM10:00AM11:00AM12:00PM1:00PM2:00PM3:00PM4:00PM5:00PM6:00PM7:00PM8:00PM9:00PM10:00PM11:00PM12:00AMWindSpeed(mph) 

# Wind Speed, Hayden, Arizona
October 22, 2008

30

‐ min Wspd

Hrly WspdR EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

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### Table 2-1 Three-Month Rolling Average Lead Concentrations During Late 2008

Period Three-Month Rolling Average Lead Concentration (μg/m 3 

### ) Original a 

### Revised b 

### July-September 2008 0.172 0.096 August-October 2008 0.184 0.079 September-November 2008 0.152 0.047 a) Calculated with data as presented in TSD. b) Calculated with data as presented in TSD, with the exception of data for August 5, September 30, and October 22 being removed.

As shown in the table above, the exclusion of data from these three days—days that according to ADEQ guidance have exceptional wind speeds—results in no lead concentrations greater than the NAAQS.



## 2.2 S UITABILITY OF 

## M ONITOR 

## L OCATION

The Hayden monitor has been placed on the roof of the maintenance building at the Town of Hayden maintenance yard. The location of the maintenance yard is given in Figure 2-6, while Figure 2-7 shows the placement of the monitor on the roof.

Figure 2-6 Location of Hayden Maintenance YardR EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

Z EPHYR E NVIRONMENTAL C ORPORATION 14 

### Figure 2-7 View of Monitor on Roof of Town of Hayden Maintenance Building (looking to the southeast)

Asarco spoke with Bob Larona, the Town of Hayden General Superintendent, to ascertain whether there are any activities that take place at the maintenance yard that could affect monitored lead concentrations at the roof of the maintenance building. Based on the conversation there are activities conducted at the yard that could affect lead concentrations at the roof. Those activities include soldering/welding (which could produce lead emissions) and vehicular traffic (which could disturb particulates on the ground in and around the maintenance building, leading to increased amounts of lead in the sampler). These activities occur throughout the week, not just for isolated periods.

Given the activities at the maintenance yard and the frequency of those activities, the potential exists for lead concentrations to be monitored at elevated levels that are not representative of the overall area or an appropriately sited source-oriented monitor. If the goal of the Hayden monitor is to support a designation, then an alternative location should be considered.R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

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## 2.3 Q UALITY 

## A SSURANCE

40 CFR Part 58 Appendix A establishes quality assurance (QA) requirements for air monitoring data collected for State and Local Air Monitoring Stations (SLAMS) network, Special Purpose Monitoring (SPM), or for purposes of Prevention of Significant Deterioration (PSD) permitting. While the Hayden monitor apparently was not established under any of these programs—it was established pursuant to a remedial investigation in a CERCLA proceeding— the data gathered at the Hayden monitor must nonetheless meet the QA requirements of 40 CFR 58 Appendix A if they are to be used to define a
nonattainment area.

The QA requirements specified by 40 CFR 58 Appendix A are presented in Table 2-2.

Table 2-2 QA Requirements of 40 CFR 58 Appendix A

QA Requirement Citation Description Quality System Requirements 40 CFR 58, Appendix A
Section 2 Prescribes a means to manage quality of monitoring information; includes Quality Management Plan and Quality Assurance Project Plan Measurement Quality Check Requirements 40 CFR 58, Appendix A
Section 3 Prescribes requirements for performing measurement quality checks to assess data quality; includes quarterly audits of sampling system Calculations for Data Quality
Assessments 40 CFR 58, Appendix A
Section 4 Prescribes calculations for assessing data quality; includes precision estimate, bias estimate, and flow rate
calculation Reporting Requirements 40 CFR 58, Appendix A
Section 5 Prescribes reporting requirements for SLAMS and PSD monitoring

Appendix D of the TSD is labeled “ADEQ Memo Certifying Air Quality Data for the Hayden Area” and contains an internal ADEQ memo prepared on August 13, 2009 from Jon Midgley to 

## ADEQ has not reviewed the
QA procedures/information for the data it used to

propose a nonattainment designation for leadR EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

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### Ira Domsky. That memo states that “(i)nformation about quality assurance checks performed on the samplers is not available at this time.” 4



### Zephyr, accordingly, has not been able to review the QA procedures applicable and QA information required to be generated for the Hayden monitor under 40 CFR Part 58 Appendix A. Without the procedures/information, Zephyr cannot determine whether the data meet the QA requirements, and neither can the ADEQ. The ADEQ should review the procedures and information required under 40 CFR Part 58 Appendix A for the monitor, before it makes a proposal to designate an area nonattainment based on data from the monitor.



## 2.4 D ATA 

## C OMPLETENESS 

## (V ALIDATION OF 

## T HREE 

## -M ONTH 

## M EANS 

## )

Section 4.1 of the TSD briefly discusses the three consecutive three-month means that are greater than the lead NAAQS. The sampling dataset on which the three-month means assessment is based spans data collected at the Hayden monitor from November 2007 through November 2008. Table 2-3 gives the three-month means of interest.

Table 2-3 Three-month Means (Lead) Given in Table 4-1 of ADEQ Technical Support
Document

3-month Period 3-month Mean (μg/m 3 

### ) July, August, September 2008 0.172 August, September, October 2008 0.184 September, October, November 2008 0.152

According to 40 CFR 50, Appendix R Section 1(c), the design value upon which lead NAAQS compliance is based is selected, according to procedures specified in Appendix R, from amongthe valid three-month mean concentrations for the design value period. Validity of the threemonth mean is determined following procedures given in 40 CFR 50, Appendix R Section 4(c).

According to 40 CFR 50, Appendix R Section 4(c)(i), “A 3-month parameter mean is considered valid (i.e., meets the completeness requirements) if the average capture rate of the three constituent monthly means (i.e., the 3-month data capture rate) is greater than or equal to 75 percent.”

The first step in determining the validity of a three-month mean is to calculate the relevant monthly capture rates. According to 40 CFR 50, Appendix R Section 4(c)(i),

Monthly data capture rates (expressed as a percentage) are specifically calculated as the number of creditable samples for the month (including any make-up samples taken the subsequent month for missed samples in the month in question, and excluding any

4 Several requests apparently have been made to the EPA and its contractor s for quality assurance documentation. Asarco has not yet received c opies of any responses to those requests.R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

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### make-up samples taken in the month in question for missed samples in the previous month) divided by the number of scheduled samples for the month, the result then multiplied by 100 but not rounded.

Creditable samples, according to 40 CFR 50, Appendix R Section 1(c), “...are samples that are given credit for data completeness. They include valid samples collected on required sampling days and valid ‘make-up’ samples taken for missed or invalidated samples on required sampling days.”

To calculate the monthly data capture rate properly one must identify the required sampling days in order to identify creditable samples (the number of which is the numerator of the monthly capture rate) and to determine the number of scheduled samples (the denominator of the monthly capture rate). Required sampling days are equivalent to scheduled sampling days. According to 40 CFR 50, Appendix R Section 1(c), “Scheduled sampling day means a day on which sampling is scheduled based on the required sampling frequency for the monitoring site, as provided in section 58.12 of this chapter.” 40 CFR 58.12(b) provides “For Pb manual methods, at least one 24-hour sample must be collected every 6 days except during periods or seasons exempted by the Regional Administrator.” More importantly, 40 CFR 50, Appendix R confirms this scheduled sampling frequency by ex plicitly specifying the every sixth day frequency under Section 4(c)(i), that is, “For purposes of assessing data capture, Pb-TSP and
Pb-PM 10 

### data collected before January 1, 2009 will be treated with an assumed scheduled sampling frequency of every sixth day.”

Since a specific list of scheduled sampling days was not available for the Hayden monitor, the scheduled sampling days were determined by examining the monitoring data collected at the Hayden monitor given in Appendix A of the TSD. Even though the focus of the validity assessment is the three consecutive three-month periods near the end of 2008 (including the months of July 2008 through November 2008, in clusive), Zephyr reviewed the entire monitoring record (November 13, 2007 to November 30, 2008) as provided to establish patterns in sampling and sampling frequency in order to identify scheduled sampling days. Table 2-4 is the result of this review. The table indicates determined scheduled sampling days (double-lined, bordered boxes). The table also indicates when moni tored samples were collected. Specifically, the table indicates scheduled samples (red X ’s) and extra samples (blue X ’s). Sample indicators with a light green filled background correspond to collected samples that were invalidated or rejected by the monitoring contractor.REVIEW OFADEQ’STSDFORPROPOSEDLEADNAAQSBOUNDARYRECOMMENDATIONZEPHYRENVIRONMENTALCORPORATION18Table 2-4 Determined Scheduled Sample DaysR EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

Z EPHYR E NVIRONMENTAL C ORPORATION 19 

### The process of determining the scheduled sampling days was as follows (also, see Table 2-4). From the beginning of this dataset record through April 5, 2008 there is a clear, every sixth day sampling pattern based on the actual dates of sample collection. The only exception to this pattern is the three samples collected between March 14, 2008 and March 26, 2008, inclusive (see black X ’s in Table 2-4). These three samples are collected every sixth day, but the sampling does not fall into the regular scheduled pattern. Note that the Technical Memorandum, which is Appendix A of the TSD, states that extra samples began to be collected (three days after the scheduled samples) after March 28, 2008. However, extra sampling three days after scheduled sampling was not apparent until April 2008. Then, around April 11/12, 2008 the actual sample collection seems to indicate a shift in sampling pattern, as the scheduled pattern moves ahead by one day. This “new” pattern continues into early May 2008 (around May 6/7, 2008 based on an extra sample collected on May 10, 2008) when the actual sample collection seems to indicate another shift in sampling pattern. Again, the scheduled pattern moves ahead by one day. This “new” pattern continues until the end of the dataset record. The only exception to this pattern is the samples collected in September 2008 through early October 2008 (through October 12, 2008). These samples are collected every sixth day but on a shifted schedule. However, because these samples are collected every sixth day with no extra samples collected (during a period when extra samples also are supposed to be collected three days after the scheduled sample), these actual samples are assumed to be collected on scheduled sampling days.

During the period of interest of July 2008 through November 2008, there are seven scheduled samples that are missing, and four scheduled samples that are invalid (i.e., rejected). In other words only 56% [(25-11)/25] of the scheduled samples are available during this period. The Technical Memorandum states that “...due to apparent power surging issues at the Hayden station, 13 samples (October through December 2008) were not collected.” It goes on to state that “...the resulting data set is considered sizable enough for evaluation purposes in this TM.” However, this is a subjective opinion and did not include a strict data validation following the procedures under 40 CFR 50, Appendix R Section 4(c).

40 CFR 50, Appendix R Section 4(c)(i) allows make-up samples to replace missed or invalidated required scheduled samples. However, the dataset record does not indicate any make-up samples were collected. Only extra samples are indicated. Extra samples, according to 40 CFR 50, Appendix R section 1(c), “...are non-creditable samples. They are daily values that do not occur on scheduled sampling days and that can not be used as ‘make-up samples’ for missed or invalidated scheduled samples.” Therefore, the creditable samples are the valid, samples collected on the scheduled sampling days. Table 2-5 presents the number of creditable samples, the number of scheduled samples and the calculated monthly data capture rates (i.e., number of creditable samples divi ded by number of scheduled samples, multiplied by 100 but not rounded) for the months of July 2008 through November 2008.R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

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### Table 2-5 Creditable Samples, Scheduled Sampling Days and Capture Rates by
Month

Month No. of Creditable Samples No. of Scheduled Samples Capture Rate (%) July 2008 4 5 80 August 2008 3 5 60 September 2008 4 5 80

October 2008 2 5 40

November 2008 1 5 20

Table 2-6 presents the three-month data capture rates for the time periods of interest.

Table 2-6 Three-Month Data Capture Rates by Time Period

Time Period 3-month Capture Rate (%) July, August, September 2008 73 August, September, October 2008 60 September, October, November 2008 47

According to 40 CFR 50, Appendix R Section 4(c)(i), “The three-month data capture rate is the sum of the three corresponding unrounded monthly data capture rates divided by three (3) and the result rounded to the nearest integer (zero decimal places).” As an example, the calculated three-month data capture rate for the July, August, September 2008 period is 73% or [(80+60+80)/3]. Because the three-month data capture rates are less than 75%, the corresponding three-month lead means (see Table 2-3) are considered not valid (i.e., they do not meet the data completeness requirements of 40 CFR 50, Appendix R Section 4(c)(i).

However, according to 40 CFR 50, Appendix R Section 4(c)(ii), “A 3-month parameter mean that does not have at least 75 percent data capture and thus is not considered valid under 4(c)(i) shall be considered valid (and complete) if it passes either of the two following ‘data substitution’ tests, one such test for validating an above NAAQS-level (i.e., violating) 3-month
Pb-TSP or Pb-PM 10 

### mean (using actual ‘low’ reported values from the same site at about the same time of the year (i.e., in the same month) looking across three or four years),...”

The three-month means of interest are above the NAAQS level. Therefore, the “data substitution” test of interest is the above NAAQS-level test. The above NAAQS-level test, according to 40 CFR 50, Appendix R Section 4(c)(ii), is as follows:

Data substitution will be done in each month of the 3-month period that has less than 75 percent data capture; monthly capture rates are temporarily rounded to integers (zero 

## The 3

­ month capture rates

are below the 75% completeness threshold.R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

Z EPHYR E NVIRONMENTAL C ORPORATION 21 

### decimals) for this evaluation. If by substituting the lowest reported daily value for that month (year non-specific; e.g., for January) over the 38-month design value period in question for missing scheduled data in the deficient months (substituting only enough to meet the 75 percent data capture minimum), the computation yields a recalculated test 3-month parameter mean concentration above the level of the standard, then the 3- month period is deemed to have passed the diagnostic test and the level of the standard is deemed to be exceeded in that 3-month period.

Following the above NAAQS-level diagnostic test would require substitution of one missing sample in August 2008, two missing/invalid samples in October 2008 and five missing/invalid samples in November 2008. All reported monitoring data at the Hayden Monitoring Station (starting October 22, 2006) through the end of 2008 were reviewed to identify the lowest reported daily values for the months of interest. According to 40 CFR 50, Appendix R Section 4(c )(ii), “..substitution is permitted only if there are available data points from which to identify the high or low 3-year month-specific values, spec ifically if there are at least 10 data points from at least two of the three (or four for November and December) possible year-months.” This criterion is met for the months of August and November, but not for the month of October. Only 7 data points from two of the three possible year-months (5 reported values in October 2007 and 2 reported values in October 2008) are available. Therefore, the substitution is not permitted for the month of October, and, thus, the diagnostic test cannot be performed for the August, September, October 2008 and September, October, November 2008 time periods. For these time periods the data completeness requirements (at least 75% data capture) are not met
and the three-month means are considered not valid.

The data substitution diagnostic test was performed for the July, August, September 2008 time period. One missing scheduled data for August 2008 was substituted with the lowest reported value for the month of August. The lowest reported lead value for the month of August is 0.0142 μg/m 3 

### collected on August 6, 2007. The recalculated July, August, September 2008 test three-month mean is 0.166 μg/m 3 

### [(0.0718 + 0.1387 + 0.2884)/3]. This value is above the level of the lead standard, thus the three-month period is deemed to have passed the diagnostic test.



## 2.5 U NCERTAINTY 

## R EGARDING 

## D ESIGN 

## V ALUE

As defined in 40 CFR 50, Appendix R, the Design Value is the concentration “...that is compared to the NAAQS level to determine compliance; the design value for the Pb NAAQS is selected...from among the valid three-month (lead) arithmetic mean concentration(s)...” In practice it is the highest of the rolling three-month averages that are calculated.

The TSD does not contain a discussion of the Design Value. A discussion of concentrations greater than the NAAQS is contained in Section 4.1 of the TSD; in that section it refers to Appendix A of the TSD 

## The Design Value should be clearly defined before
proposing to classify an area

as nonattainment.R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

Z EPHYR E NVIRONMENTAL C ORPORATION 22 

### for more details pertaining to the monitoring results that confirm the Hayden area is in
nonattainment for lead.

Appendix A of the TSD is labeled as “EPA’s Air Quality Study of the Hayden Area,” and consists of a Technical Memorandum prepared on December 31, 2008 from CH2M Hill to John Hillenbrand of EPA. The Technical Memorandum includes a summary of monitoring conducted at Hayden and provides tables of all monitoring results (pollutant and meteorological) on a daily basis (Table 1 in Appendix A of the TSD contains the Hayden information).

Following these detailed tables there is an individual page that presents a Design Value of 0.21 μg/m 3 

### for lead for the Hayden monitor for the period 2006-2008. However, there is no explanation as to the derivation of this value; furthermore, a close inspection reveals that the data presented in Appendix A of the TSD do not support the 0.21 μg/m 3 

### value.

Zephyr looked into this discrepancy further and ascertained that the Design Value of 0.21 μg/m 3 

### may be based on data provided in electronic format by John Hillenbrand of EPA to Jack Garrity of Asarco on September 23, 2009 (these data are presented in the spreadsheet in Appendix A of this report). It is not clear the spreadsheet data have been vetted for exceptional events, quality assurance and data completeness.

It is unclear, therefore, which, if any, dataset is appropriate to use. While the ADEQ apparently makes its proposal based on the data in Appendix A of the TSD, the TSD’s sole actual reference to a Design Value may rely on a completely different set of data which may or may not have undergone validation under the rules. The ADEQ should clearly establish and validate the Design Value for comparison to the NAAQS. Without a clearly established and properly validated Design Value a designation of nonattainment is not justified.R EVIEW OF ADEQ’ S TSD FOR P ROPOSED L EAD NAAQS B OUNDARY R ECOMMENDATION

Z EPHYR E NVIRONMENTAL C ORPORATION 23 

## APPENDIX A HAYDEN AIR QUALITY MONITORING DATA RECEIVED FROM EPA ON SEPTEMBER 23, 2009Result Qualifier NAAQS Hayden 10/22/06 μg/m 3 0.0024 * 0.15 Hayden 11/03/06 μg/m 3 0.0266 0.15 Hayden 11/09/06 μg/m 3 0.0141 0.15 Hayden 11/11/06 μg/m 3 0.044 0.15 Hayden 11/21/06 μg/m 3 0.5947 0.15 Hayden 11/27/06 μg/m 3 0.0191 0.15 Hayden 12/03/06 μg/m 3 0.1595 0.15 Hayden 12/09/06 μg/m 3
Hayden 12/15/06 μg/m 3 0.0329 J 0.15 Hayden 12/21/06 μg/m 3 0.0027 * 0.15 Hayden 12/27/06 μg/m 3 0.0143 0.15

Average 0.0834

Hayden 01/08/07 μg/m 3 0.47 0.15 Hayden 01/14/07 μg/m 3 0.0167 0.15 Hayden 01/20/07 μg/m 3 0.0043 0.15 Hayden 01/26/07 μg/m 3 0.0099 0.15 Hayden 02/01/07 μg/m 3 0.005 0.15 Hayden 02/07/07 μg/m 3 0.0103 0.15 Hayden 02/13/07 μg/m 3 0.037 0.15 Hayden 02/19/07 μg/m 3 0.0173 0.15 Hayden 02/25/07 μg/m 3 0.0105 0.15 Hayden 03/03/07 μg/m 3 0.1444 0.15 Hayden 03/09/07 μg/m 3 R R 0.15 Hayden 03/15/07 μg/m 3 0.032 0.15 Hayden 03/21/07 μg/m 3 0.0885 0.15 Hayden 03/27/07 μg/m 3 0.0227 0.15 Hayden 04/02/07 μg/m 3 0.028 0.15 Hayden 04/20/07 μg/m 3 0.0122 0.15 Hayden 04/26/07 μg/m 3 0.0324 0.15 Hayden 05/02/07 μg/m 3 R R 0.15 Hayden 05/08/07 μg/m 3 0.0774 0.15 Hayden 05/14/07 μg/m 3 0.0257 0.15 Hayden 05/20/07 μg/m 3 0.0127 0.15 Hayden 05/26/07 μg/m 3 0.0253 0.15 Hayden 06/01/07 μg/m 3 0.046 0.15 Hayden 06/07/07 μg/m 3 0.0048 0.15 Hayden 06/13/07 μg/m 3 0.0238 0.15 Hayden 06/19/07 μg/m 3 0.0298 0.15 Hayden 06/25/07 μg/m 3 0.0299 0.15 Hayden 07/01/07 μg/m 3 0.0382 0.15 Hayden 07/07/07 μg/m 3 R R 0.15 Hayden 07/13/07 μg/m 3 0.021 0.15 Hayden 07/19/07 μg/m 3 0.0986 0.15 Hayden 07/25/07 μg/m 3 0.0136 0.15 Hayden 07/31/07 μg/m 3 0.0208 0.15 Hayden 08/06/07 μg/m 3 0.0142 0.15 Lead
Location Sample

Date Units

Page 1 of 4Result Qualifier NAAQS Lead
Location Sample

Date Units Hayden 08/12/07 μg/m 3 0.0268 0.15 Hayden 08/18/07 μg/m 3 0.0429 0.15 Hayden 08/24/07 μg/m 3 0.0182 0.15 Hayden 08/30/07 μg/m 3 0.517 0.15 Hayden 09/05/07 μg/m 3 0.0294 0.15 Hayden 09/11/07 μg/m 3 0.8362 0.15 Hayden 09/17/07 μg/m 3 0.0803 0.15 Hayden 09/23/07 μg/m 3 0.0033 0.15 Hayden 09/29/07 μg/m 3 0.0273 0.15 Hayden 10/05/07 μg/m 3 0.0035 0.15 Hayden 10/11/07 μg/m 3 0.046 0.15 Hayden 10/17/07 μg/m 3 0.0194 0.15 Hayden 10/22/07 μg/m 3 0.5156 0.15 Hayden 10/27/07 μg/m 3 0.0242 0.15 Hayden 11/01/07 μg/m 3 0.0202 0.15 Hayden 11/07/07 μg/m 3 0.3183 0.15 Hayden 11/13/07 μg/m 3 0.0049 0.15 Hayden 11/19/07 μg/m 3 0.042 0.15 Hayden 11/25/07 μg/m 3 0.0538 0.15 Hayden 12/07/07 μg/m 3 0.2119 0.15 Hayden 12/13/07 μg/m 3 0.0944 0.15

Average 0.0838

Hayden 01/12/08 μg/m 3 0.1487 0.15 Hayden 01/18/08 μg/m 3 0.0613 0.15 Hayden 02/17/08 μg/m 3 0.0291 0.15 Hayden 02/23/08 μg/m 3 0.0081 0.15 Hayden 02/29/08 μg/m 3 0.0764 0.15 Hayden 03/06/08 μg/m 3 0.0697 0.15 Hayden 03/12/08 μg/m 3 R R 0.15 Hayden 03/14/08 μg/m 3 0.064 0.15 Hayden 03/20/08 μg/m 3 0.0152 0.15 Hayden 03/26/08 μg/m 3 0.0125 0.15 Hayden 03/30/08 μg/m 3 0.0024 * 0.15 Hayden 04/05/08 μg/m 3 0.0305 0.15 Hayden 04/12/08 μg/m 3 0.4627 0.15 Hayden 04/15/08 μg/m 3 0.059 0.15 Hayden 04/18/08 μg/m 3 0.1272 0.15 Hayden 04/21/08 μg/m 3 0.0299 0.15 Hayden 04/24/08 μg/m 3 0.0097 0.15 Hayden 05/10/08 μg/m 3 0.022 0.15 Hayden 05/13/08 μg/m 3 0.1163 0.15 Hayden 05/16/08 μg/m 3 0.288 0.15 Hayden 05/19/08 μg/m 3 0.0236 0.15 Hayden 05/22/08 μg/m 3 0.0166 0.15 Hayden 05/28/08 μg/m 3 0.0361 0.15 Hayden 05/31/08 μg/m 3 0.028 0.15

Page 2 of 4Result Qualifier NAAQS Lead
Location Sample

Date Units Hayden 06/03/08 μg/m 3 0.0547 0.15 Hayden 06/06/08 μg/m 3 0.0185 0.15 Hayden 06/09/08 μg/m 3 0.0843 0.15 Hayden 06/12/08 μg/m 3 0.0746 0.15 Hayden 06/15/08 μg/m 3 0.1255 0.15 Hayden 06/18/08 μg/m 3 0.033 0.15 Hayden 06/21/08 μg/m 3 0.1123 0.15 Hayden 07/09/08 μg/m 3 0.3432 0.15 Hayden 07/12/08 μg/m 3 0.0062 0.15 Hayden 07/15/08 μg/m 3 0.0191 0.15 Hayden 07/18/08 μg/m 3 0.047 0.15 Hayden 07/21/08 μg/m 3 0.0205 0.15 Hayden 07/24/08 μg/m 3 0.0731 0.15 Hayden 07/27/08 μg/m 3 0.0011 0.15 Hayden 07/30/08 μg/m 3 0.0132 0.15 Hayden 08/02/08 μg/m 3 0.0347 0.15 Hayden 08/05/08 μg/m 3 0.1629 0.15 Hayden 08/08/08 μg/m 3 0.457 0.15 Hayden 08/11/08 μg/m 3 0.0417 0.15 Hayden 08/14/08 μg/m 3 0.1646 0.15 Hayden 08/17/08 μg/m 3 0.1981 0.15 Hayden 08/20/08 μg/m 3 0.0363 0.15 Hayden 09/12/08 μg/m 3 0.0136 0.15 Hayden 09/18/08 μg/m 3 0.0462 0.15 Hayden 09/24/08 μg/m 3 0.1263 0.15 Hayden 09/30/08 μg/m 3 0.9676 0.15 Hayden 10/06/08 μg/m 3 0.02 0.15 Hayden 10/12/08 μg/m 3 0.0234 0.15 Hayden 10/22/08 μg/m 3 0.1968 0.15 Hayden 10/25/08 μg/m 3 0.042 0.15 Hayden 10/28/08 μg/m 3 0.3002 0.15 Hayden 11/09/08 μg/m 3 0.0887 0.15 Hayden 11/12/08 μg/m 3 0.0071 0.15 Hayden 11/21/08 μg/m 3 0.984 0.15 Hayden 11/24/08 μg/m 3 0.111 0.15 Hayden 11/27/08 μg/m 3 0.1731 0.15 Hayden 11/30/08 μg/m 3 0.0328 0.15 Hayden 12/06/08 μg/m 3 0.0113 0.15 Hayden 12/12/08 μg/m 3 0.1094 0.15 Hayden 12/15/08 μg/m 3 0.1166 0.15 Hayden 12/27/08 μg/m 3 0.0944 0.15 Hayden 12/30/08 μg/m 3 0.0115 0.15

Average 0.1128

Hayden 01/02/09 μg/m 3 0.0174 0.15 Hayden 01/19/09 μg/m 3 0.1583 0.15 Hayden 02/01/09 μg/m 3 0.1483 0.15

Page 3 of 4Result Qualifier NAAQS Lead
Location Sample

Date Units Hayden 02/04/09 μg/m 3 0.9647 0.15 Hayden 02/06/09 μg/m 3 0.0433 0.15 Hayden 02/12/09 μg/m 3 0.0109 0.15

02/18/09 Hayden 02/20/09 μg/m 3 0.0567 0.15

02/24/09 Hayden 02/26/09 μg/m 3 0.1353 0.15

03/02/09 Hayden 03/04/09 μg/m 3 0.0253 0.15

03/08/09 Hayden 03/10/09 μg/m 3 0.1507 0.15 Hayden 03/13/09 μg/m 3 0.0706 0.15

03/14/09 Hayden 03/19/09 μg/m 3 0.0937 0.15

03/20/09 Hayden 03/26/09 μg/m 3 0.0807 0.15 Hayden 04/01/09 μg/m 3 0.1023 0.15 Hayden 04/07/09 μg/m 3 0.4633 0.15 Hayden 04/13/09 μg/m 3 0.0174 0.15 Hayden 04/19/09 μg/m 3 0.0455 0.15 Hayden 04/25/09 μg/m 3 0.0226 0.15 Hayden 05/01/09 μg/m 3 0.0645 0.15 Hayden 05/07/09 μg/m 3 0.0299 0.15 Hayden 05/13/09 μg/m 3 0.0913 0.15 Hayden 05/19/09 μg/m 3 0.0249 0.15 Hayden 05/25/09 μg/m 3 0.0050 0.15 Hayden 05/31/09 μg/m 3 0.0056 0.15 Hayden 06/06/09 μg/m 3 0.0040 0.15 Hayden 06/12/09 μg/m 3 0.0039 0.15 Hayden 06/18/09 μg/m 3 0.0083 0.15 Hayden 06/24/09 μg/m 3 0.0102 0.15

Average 0.1020
Maximum 0.9647

* = The result is less than three times the level o f uncertainty.

J = Estimated value

NA = Not available R = Rejected due to filter damage

Page 4 of 4