UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION III

1650 Arch Street

Philadelphia, Pennsylvania 19103

DATE: 7/9/2014

SUBJECT: Technical Support Document Regarding Lead Monitoring Data: Pennsylvania: 

Lyons; Clean Data Determination for the Lyons 2008 Lead Nonattainment Area

FROM: Ellen Schmitt, Life Scientist /s/ 7/8/2014

Office of Air Program Planning

Howard Schmidt, Environmental Scientist /s/ 7/9/2014

Office of Air Monitoring & Analysis

TO: File

THRU: Cristina Fernandez, Associate Director /s/ 7/8/2014

Office of Air Program Planning

Alice Chow, Associate Director /s/ 7/9/2014

Office of Monitoring & Analysis

This document provides a technical review of the air quality monitoring data used to support the 

Environmental Protection Agency’s (EPA’s) proposed determination that the Lyons 2008 lead

(Pb) nonattainment area has attained the 2008 lead national ambient air quality standard

(NAAQS).

A. INTRODUCTION

EPA is proposing to determine that the Lyons Area (bounded by Kutztown Borough, Lyons 

Borough, Maxatawny Township and Richmond Township) has clean data for the 2008 Pb 

NAAQS. 
2

B. BACKGROUND

On November 12, 2008 (73 FR 66964), EPA established a 2008 primary and secondary Pb 

NAAQS at 0.15 micrograms per cubic meter (μg/m3) based on a maximum arithmetic 3-month 

mean concentration for a 3-year period. See 40 CFR 50.16. On November 22, 2010 (75 FR 

71033), EPA published its initial air quality designations and classifications for the 2008 lead 

NAAQS based upon air quality monitoring data for calendar years 2007-2009. The November 

22, 2010 Federal Register publication included the nonattainment designation of an area located 

in Lyons, PA within Berks County and which will hereby be referred to as “Lyons Area” or 

“Area.” See CFR 81.339. The initial 2008 Pb NAAQS designations, including the Lyons Area 

nonattainment designation, became effective on December 31, 2010.1

On March 31, 2014, the Commonwealth of Pennsylvania, through the Pennsylvania 

Department of Environmental Protection (PADEP), submitted a request to EPA to make a 

determination that the Lyons nonattainment area for the 2008 Pb NAAQs has attained the 2008 

Pb NAAQS, based on certified, quality-controlled monitoring data from 2011 through 2013.

EPA is proposing to determine that the Lyons Area (bounded by Kutztown Borough, Lyons 

Borough, Maxatawny Township and Richmond Township) has clean data for the 2008 Pb 

NAAQS. This proposed determination for the Lyons nonattainment area would suspend the 

requirements to submit an attainment demonstration for the Lyons area, including associated 

reasonably available control measures (RACM), a reasonable further progress (RFP) plan, 

contingency measures, and any other planning SIPs related to attainment of the 2008 Pb

NAAQS. 

If this proposed determination is finalized, the suspension of the attainment demonstration 

requirements listed above would continue until such time, if any, that EPA subsequently 

determines that the area has violated the 2008 Pb NAAQS. If after notice-and-comment in the 

Federal Register, the Area violates the 2008 Pb NAAQS, the basis for the suspension of these 

 

1 EPA completed a second and final round of designations for the 2008 Pb NAAQS on November 22, 2011. See 76 

FR 72097. No additional areas in Pennsylvania were designated as nonattainment for the 2008 Pb NAAQS. 
3

attainment planning requirements would no longer exist for the Lyons Area, and the Area would 

thereafter have to address the pertinent requirements. 

The determination that EPA proposes with this Federal Register notice, that the air quality 

data shows attainment of the 2008 Pb NAAQS, is not equivalent to the redesignation of this area 

to attainment. This proposed action, if finalized, would not constitute a redesignation to 

attainment under section 107(d)(3) of the Clean Air Act (CAA), because EPA would not yet 

have an approved maintenance plan for the area, as required under section 175A of the CAA, nor 

a determination that the area has met the other requirements for redesignation. The 

nonattainment designation status of the Lyons Area would remain for the 2008 Pb NAAQS until 

such time, if any, that EPA determines that the area has met the CAA requirements for 

redesignation to attainment.

This proposed determination that the Lyons Area has clean data for the 2008 Pb NAAQS, 

and any final determination, will have no effect on, and is not related to, any future designation 

determination that EPA may make based on future lead NAAQS for the Lyons, PA 

nonattainment area. Conversely, any future designation determination of the Lyons Area, based 

on future lead NAAQS, will not have any effect on the determination proposed by this notice. 

C. EPA’S REQUIREMENTS

1. EPA’s Clean Data Policy

According to CAA section 172(c)(1), attainment demonstration requirements “shall provide 

for attainment of the [NAAQS].” EPA has interpreted this requirement as not applying to areas 

that have attained the standard. If an area has attained the standard, there is no need to submit a 

plan demonstrating how the area will reach attainment. In the General Preamble (57 FR 13564), 

EPA stated that no other measures to provide for attainment would be needed by areas seeking 

redesignation to attainment since “attainment will have been reached.” See also Memorandum 

from John Calcagni, “Procedures for Processing Requests to Redesignate Areas to Attainment,”

(September 4, 1992).
4

A component of the attainment plan specified under section 172(c)(1) is the requirement to 

provide for “the implementation of all reasonably available control measures as expeditiously as 

practicable.” Since RACM is an element of the attainment demonstration, see General Preamble 

(57 FR 13560), for the same reason the attainment demonstration no longer applies by its own 

terms, RACM also no longer applies. Furthermore, EPA has consistently interpreted this 

provision to require only implementation of potential RACM measures that could advance 

attainment.2 Thus, where an area is already attaining the standard, no additional RACM 

measures are required. 

In 1995, based on the interpretation of CAA sections 171 and 172, and section 182 in the 

General Preamble, EPA set forth what has become known as its “Clean Data Policy” for the 1-

hour ozone NAAQS. See Memorandum from John S. Seitz, Director, Office of Air Quality 

Planning and Standards, “RFP, Attainment Demonstration, and Related Requirements for Ozone 

Nonattainment Areas Meeting the Ozone National Ambient Air Quality Standard” (May 10, 

1995). In 2004, EPA indicated its intention to extend the Clean Data Policy to the fine 

particulate matter (PM2.5) NAAQS. See Memorandum from Steve Page, Director, EPA Office of 

Air Quality Planning and Standards, “Clean Data Policy for the Fine Particle National Ambient 

Air Quality Standards” (December 14, 2004).

CAA section 172(c)(2) provides that state implementation plan (SIP) provisions in 

nonattainment areas must require “reasonable further progress.” The term “reasonable further 

progress” is defined in section 171(1) as “such annual incremental reductions in emissions of the 

relevant air pollutant as are required by this part or may reasonably be required by the 

Administrator for the purpose of ensuring attainment of the applicable NAAQS by the applicable 

date.” Thus, by definition, the “reasonable further progress” provision requires only such 

reductions in emissions as are necessary to attain the NAAQS. If an area has attained the 

NAAQS, the purpose of the RFP requirement has been fulfilled, and since the area has already 

attained, showing that the State will make RFP towards attainment the RFP requirement “[has] 

no meaning at that point.” General Preamble, 57 FR 13498, 13564 (April 16, 1992).

 

2 This interpretation was adopted in the General Preamble, see 57 FR 13498, and has been upheld as applied to the 

Clean Data Policy, as well as to nonattainment SIP submissions. See NRDC v. EPA, 571 F.3d 1245 (D.C. Cir. 

2009); Sierra Club v. EPA, 294 F.3d 155 (D.C. Cir. 2002). 
5

CAA section 172(c)(9) provides that SIPs in nonattainment areas “shall provide for the 

implementation of specific measures to be undertaken if the area fails to make reasonable further 

progress, or to attain the [NAAQS] by the attainment date applicable under this part. Such 

measures shall be included in the plan revision as contingency measures to take effect in any 

such case without further action by the State or [EPA].” This contingency measure requirement 

is inextricably tied to the reasonable further progress and attainment demonstration requirements. 

Contingency measures are implemented if reasonable further progress targets are not achieved, 

or if attainment is not realized by the attainment date. Where an area has already achieved 

attainment by the attainment date, it has no need to rely on contingency measures to come into 

attainment or to make further progress to attainment. As EPA stated in the General Preamble: 

“The section 172(c)(9) requirements for contingency measures are directed at ensuring RFP and 

attainment by the applicable date.” See 57 FR 13564. Thus these requirements no longer apply 

when an area has attained the standard.

2. EPA’s Requirements for Compliance with the 2008 Lead NAAQS

The 2008 Pb NAAQS are met when the maximum arithmetic 3-month mean concentration 

for a 3-year period, as determined in accordance with 40 CFR part 50, Appendix R, is less than 

or equal to the 2008 Pb NAAQS level of 0.15 μg/m3. The 2008 Pb NAAQS design value for an 

area is determined by the highest valid 3-month arithmetic mean concentration identified within 

a 38-month period that consists of the most recent 3-year calendar period (36 months) plus the 

two preceding months, for a total of 36 3-month periods. Therefore, an area’s design value 

meets the 2008 Pb NAAQS when, for all relevant monitoring sites, the maximum arithmetic 3-

month mean concentration for the applicable 38-month period is less than or equal to 0.15 μg/m3.

3-month means

A 3-month mean is determined by averaging three consecutive monthly means. 

A monthly mean is the average concentration for an individual calendar month 

and is calculated using all available valid daily data for that month, giving equal 

weight to each day.3,4 Each distinct monthly mean will be included in three (3)

 

3 According to 40 CFR 50.12, the state or local government agency that is responsible for monitoring under the 

CAA, must collect at least one 24-hour ambient air lead sample every 6 days except during periods or seasons 

exempted by the Regional Administrator. 
6

different 3-month means. For example, the November 2011 monthly mean 

would be included in: (1) The September 2011-October 2011-November 2011

3-month mean, (2) the October 2011-November 2011-December 2011 3-month 

mean, and (3) the November 2011-December 2011-January 2012 3-month 

mean. According to 40 CFR 50, Appendix R, 3-month means are computed on 

a rolling, overlapping basis. As a convention, the name of the 3-month mean is 

based on the last month included in the calculation (e.g., the “November 2011”

3-month rolling mean includes the September, October, and November 2011 

monthly means). The procedures for calculating monthly means and 3-month 

means, and identifying Pb design values are given in section six (6) of 40 CFR 

part 50, Appendix R.

Completeness requirements and substitution tests (as specified in 40 CFR part 

50, Appendix R)

A 3-month mean is considered valid if the average of the data capture rate of the 

three constituent monthly means is greater than or equal to 75 percent (%). The 

capture rate of a monthly mean is determined by the number of scheduled 

sampling days within that month that produced valid data. If a 3-month mean 

does not have at least a 75% data capture and therefore is not considered valid 

(or complete), it can still be used when calculating the design value if it passes 

one of the two data substitution tests described in 40 CFR part 50, Appendix R.

The type of substitution test used is based on if, using the available incomplete 

data, the result is above or below 2008 Pb NAAQS (0.15 μg/m3).

When a 3-month mean, calculated using incomplete data, is violating (i.e.,

above) the NAAQS, the “above-the-NAAQS-level” substitution test can be used 

for each month of the 3-month period with less than 75% data. This test consists 

of substituting the lowest reported daily value for that month (year non-specific; 

e.g. January), over the 38-month design value period, in place of the missing data 

in the incomplete months, substituting only enough to meet the 75% data capture 

minimum. If the recalculated 3-month mean concentration is above the level of 

 

4 Valid daily samples are those that follow the conventions found under 40 CFR part 50, Appendix R. 
7

the 2008 Pb NAAQS, then the 3-month period is considered to have “passed” the 

test and the level of the standard is deemed to have been exceeded in that 3-

month period.

If an incomplete 3-month mean is below the NAAQS, the “below NAAQS level” 

test can be applied in each month of the 3-month period with less than 75% data, 

but at least 50%. This test consists of substituting the highest reported daily 

value for that particular month, over the 38-month design value period, will be 

used in place of the missing data in the incomplete period, to bring the data 

capture rate up to 100%. If the recalculated 3-month mean concentration is equal 

to or is less than the 2008 Pb NAAQS level, then the 3-month period is deemed 

to have “passed” the test and the level of the standard is deemed not to have been 

exceeded in that 3-month period.

Both substitution tests are merely diagnostic in nature intending to confirm that 

there is a very high likelihood if not certainty that the incomplete 3-month mean 

(the one based on actual reported data) reflects the true over/under NAAQS level 

status for that 3-month period. The recalculated 3-month mean from either of

these data substitution tests is not considered the actual 3-month mean and shall 

not be used in the determination of design values. The 3-month mean of the data 

actually reported, even if incomplete, shall be the one used to determine the 

site’s design value.

D. EPA’S EVALUATION OF THE LYONS AREA’S LEAD AIR MONITORING DATA 

1. Lyons Area’s Air Monitoring Data for the 2008 Lead NAAQS

The Lyons Area’s monitoring network consists of two monitoring locations: Lyons Boro 

(AQS ID 42-011-0021) with one Federal Equivalent Method (FEM) monitor and Lyons Park

(AQS ID 42-011-0022) with collocated FEM monitors. Monitors at both Lyons Boro and Lyons 

Park were placed into service on January 2, 2010. Monitor locations were determined through a 

modeling analysis completed by PADEP and a site selection process which includes, but is not 
8

limited to, evaluating land/lease availability, worker safety, accessing electricity, and 

coordinating with the EPA regional office. 

The Commonwealth of Pennsylvania submitted quality assured, quality controlled, and 

certified air quality monitoring data for the 2008 lead NAAQS into EPA’s Air Quality System 

(AQS) database. EPA has reviewed the ambient air monitoring data for lead for the Lyons Area 

in accordance with the provisions of 40 CFR part 50, Appendix R. The monitoring data 

evaluated for the Lyons Area corresponds to the 36 3-month means collected during the 38 

months from November 2010 to December 2013, which is the most recent certified, qualityassured, quality-controlled data available for the Area. 

2. Incompleteness Issues and Data Substitution for Lyons Boro Monitoring Site

The Lyons Park (ID 42-011-0022) collocated monitors have complete data for the 2011-2013 

rolling 3-month period. The Lyons Boro monitoring site (ID 42-011-0021) did not meet the 

completeness criteria for two 3-month periods: November 2011 (i.e., September to November of 

2011) and December 2012 (i.e., October to December 2012). Table 1, below, provides the 

monthly means, 3-month mean, and capture rates for the Lyons Boro monitor during the 38-

month monitoring period. Table 1 also identifies the validity of each 3-month mean value.
9

Table 1. Lyons Boro Monitoring Site Data, from November 2010 to December 2013

Year Month

Monthly 

Mean

(μg/m3)

Monthly 

Capture 

Rate

3-month 

Mean

(μg/m3)

3-month 

Capture 

Rate

Valid 3-

month 

mean? Y/N

2010 November 0.0464 100% 0.05 87% Y

2010 December 0.0478 100% 0.05 87% Y

2011 January 0.01525 80% 0.04 93% Y

2011 February 0.0224 100% 0.03 93% Y

2011 March 0.0116 100% 0.02 93% Y

2011 April 0.01575 80% 0.02 93% Y

2011 May 0.012 100% 0.01 93% Y

2011 June 0.0532 100% 0.03 93% Y

2011 July 0.0324 100% 0.03 100% Y

2011 August 0.0397 100% 0.04 100% Y

2011 September 0.0333 80% 0.04 93% Y

2011 October 0.04625 80% 0.04 87% Y

2011 November 0.0200 60% 0.03 73% N

2011 December 0.0216 100% 0.03 80% Y

2012 January 0.0322 100% 0.02 87% Y

2012 February 0.0362 100% 0.03 100% Y

2012 March 0.0422 100% 0.04 100% Y

2012 April 0.0240 100% 0.03 100% Y

2012 May 0.0138 100% 0.03 100% Y

2012 June 0.0392 100% 0.03 100% Y

2012 July 0.02975 80% 0.03 93% Y

2012 August 0.03225 67% 0.03 82% Y

2012 September 0.0988 100% 0.05 82% Y

2012 October 0.02125 80% 0.05 82% Y

2012 November 0.0127 60% 0.04 80% Y

2012 December 0.0160 80% 0.02 73% N

2013 January 0.0284 100% 0.02 80% Y

2013 February 0.0180 100% 0.02 93% Y

2013 March 0.0130 100% 0.02 100% Y

2013 April 0.0502 100% 0.03 100% Y

2013 May 0.0410 100% 0.03 100% Y

2013 June 0.0308 100% 0.04 100% Y

2013 July 0.0272 100% 0.03 100% Y

2013 August 0.0628 100% 0.04 100% Y

2013 September 0.0184 100% 0.04 100% Y

2013 October 0.0383 100% 0.04 100% Y

2013 November 0.0230 100% 0.03 100% Y

2013 December 0.0436 100% 0.03 100% Y
10

As seen in table 2, below, the Lyons Boro monitor failed to obtain two out of the six required 

valid samples in November 2011, thereby only having a 60% capture rate for that month. 

Although the previous two months (September and October 2011) each had greater than a 75% 

capture rate, the overall 3-month capture rate for the November 2011 rolling 3-month period was 

73%, less than the required 75% needed for a 3-month sample to be considered complete. 

Table 2. Lyons Boro Monitoring Site Incomplete Data, September to November 2011

Month/Year Sample 

Date

Daily 

Value 

(μg/m3)

Monthly 

Mean 

(μg/m3)

Monthly 

Capture 

Rate

3-month 

Mean 

(μg/m3)

3-month 

Capture 

Rate

September 

2011

6-Sept-11 0.011

0.0333 80%

0.03 73%

12-Sept-11 x

18-Sept-11 0.011

24-Sept-11 0.035

30-Sept-11 0.076

October 

2011

6-Oct-11 0.038

0.04625 80%

12-Oct-11 0.011

18-Oct-11 0.047

24-Oct-11 0.089

30-Oct-11 x

November 

2011

5-Nov-11 0.012

0.0200 60%

11-Nov-11 0.037

17-Nov-11 x

23-Nov-11 x

29-Nov-11 0.011

Note: “x” indicates that no valid data was captured on that day.

The data in table 3, below, show that the individual monthly capture rates for the Lyons Boro 

monitor’s December 2012 rolling 3-month period are as follows: October 2012, 80%, November 

2012, 60%, and December 2012, 80%. The resulting 3-month capture rate for the Lyons Boro 

monitor’s December 2012 rolling 3-month capture rate is 73%, below the required 75% needed 

for a 3-month sample to be considered complete. 
11

Table 3. Lyons Boro Monitoring Site Incomplete Data, October to December 2012

Month/

Year

Sample 

Date

Daily 

Value

(μg/m3)

Monthly 

Mean

(μg/m3)

Monthly 

Capture Rate

3-month 

Mean

(μg/m3)

3-month 

Capture 

Rate

October

2012

6-Oct-12 0.022

0.02125 80%

0.02 73%

12-Oct-12 0.029

18-Oct-12 0.010

24-Oct-12 0.024

30-Oct-12 x

November 

2012

5-Nov-12 0.011

0.0127 60%

11-Nov-12 0.016

17-Nov-12 0.011

23-Nov-12 x

29-Nov-12 x

December 

2012

5-Dec-12 0.011

0.0160 80%

11-Dec-12 x

17-Dec-12 0.011

23-Dec-12 0.031

29-Dec-12 0.011

Note: “x” indicates that no valid data was captured on that day.

The incomplete November 2011 and December 2012 3-month mean values were both below 

the level of the 2008 Pb NAAQS. To determine whether these two 3-month means are valid for 

determining compliance with the 2008 lead NAAQS, EPA applied the below-NAAQS-level data 

substitution test to the incomplete 3-month periods from the Lyons Boro monitor. 

Data substitution calculation for Lyons Boro’s incomplete data for the November 

2011 3-month period

As shown in table 4, below, the 3-month mean concentration for September 2011 

through November 2011 is 0.03 g/m3(see table 2) with missing Pb daily 

samples on 9/12/2011, 10/30/2011, 11/17/2011, and 11/23/2011. The highest 

reported daily values for these particular incomplete months (i.e., September, 

October, and November) over the 38-month period of November 2010 to 

December 2013 were used to fill in for the missing data during each month of the

incomplete 3-month period. The following highest values were used: 0.324 

g/m3for September, 0.096 g/m3for October, and 0.060 g/m3for November. 

The “test” or recalculated 3-month mean for the Lyons Boro incomplete 
12

November 2011 period is 0.06 g/m3after using the month-specific maximums as 

replacement values for the four missing samples.

Table 4. Data Substitution for Lyons Boro Monitoring Site Incomplete Data, September to 

November 2011

Month/Year Sample 

Date

Daily 

Value

(μg/m3)

Substituted 

Data

(μg/m3) 

Recalculated 

Monthly 

Mean

(μg/m3)

Monthly 

Capture 

Rate

“Test” 

3-month 

Mean

(μg/m3)

3-month 

Capture 

Rate

September 

2011

6-Sept-11 0.011 -

0.091 100%

0.06 100%

12-Sept-11 x 0.324

18-Sept-11 0.011 -

24-Sept-11 0.035 -

30-Sept-11 0.076 -

October 2011

6-Oct-11 0.038 -

0.056 100%

12-Oct-11 0.011 -

18-Oct-11 0.047 -

24-Oct-11 0.089 -

30-Oct-11 x 0.096

November 

2011

5-Nov-11 0.012 -

0.036 100%

11-Nov-11 0.037 -

17-Nov-11 x 0.060

23-Nov-11 x 0.060

29-Nov-11 0.011 -

Note: “x” indicates that no valid data was captured on that day; “-” indicates that no substitution 

data applies.

Data substitution calculation for Lyons Boro’s incomplete data for the December 

2012 3-month period

As shown in table 5, below, the 3-month mean concentration for October 2012 

through December 2012 is 0.02 g/m3(see table 3) with missing Pb daily samples

on 10/30/2012, 11/23/2012, 11/29/2012, and 12/11/2012. The highest reported 

daily values for these particular incomplete months (i.e., October, November, and 

December) over the 38-month period of November 2010 to December 2013 were 

used to fill in for the missing data during each the incomplete 3-month period. 

The following highest values were used: 0.096 g/m3for October, 0.060 g/m3

for November, and 0.107 g/m3for December. The “test” 3-month mean for

Lyons Boro incomplete December 2012 period is 0.03 g/m3after using the 

month-specific maximums as replacement values for the four missing samples.
13

Table 5. Data Substitution for Lyons Boro Monitoring Site Incomplete Data, September to 

November 2011

Month/Year Sample 

Date

Daily 

Value

(μg/m3)

Substituted 

Data

Recalculated 

Monthly 

Mean

(μg/m3)

Monthly 

Capture 

Rate

“Test” 

3-month 

Mean 

(μg/m3)

3-month 

Capture 

Rate

October 

2012

6-Oct-12 0.022 -

0.036 100%

0.03

100%

12-Oct-12 0.029 -

18-Oct-12 0.010 -

24-Oct-12 0.024 -

30-Oct-12 x 0.096

November 

2012

5-Nov-12 0.011 -

0.032 100%

11-Nov-12 0.016 -

17-Nov-12 0.011 -

23-Nov-12 x 0.060

29-Nov-12 x 0.060

December 

2012

5-Dec-12 0.011 -

0.034 100%

11-Dec-12 x 0.107

17-Dec-12 0.011 -

23-Dec-12 0.031 -

29-Dec-12 0.011 -

After making the data substitutions, the re-calculated 3-month means for November 2011

(0.06 g/m3), and December 2012 (0.03 g/m3) are below the level of the 2008 Pb standard (0.15 

g/m3). This indicates that the three 3-month means have “passed” the substitution test and that 

the level of the standard is deemed not to have been exceeded during each of these 3-month 

periods. The recalculated 3-month means from the data substitution test are not considered the 

actual 3-month mean and were not used in the determination of design values. The 3-month

means of the data actually reported, even if incomplete, were used to determine the site-specific 

design values. Thus, the 3-month means actually reported during September to November 2011

(0.03 g/m3) and October to December 2012 (0.02 g/m3), which were calculated using 

incomplete data, are considered valid, and were used in calculating the 2011-2013 design value 

for the Lyons Area. 
14

3. Lyons Area’s 2013 Design Values for the 2008 Pb NAAQS

The design values for the Lyons Boro and Lyons Parks monitors, based on certified, qualitycontrolled monitoring data from 2011 through 2013 can be found in table 6. As shown in table 6

below, the highest site specific design value for the Lyons Area is 0.05 μg/m3, based on data for 

Lyons Boro monitoring site. Thus, in accordance with 40 CFR 50 and based on valid data, the 

Lyons Area’s design value for 2011-2013 is 0.05 μg/m3, which is well below the level of the 

2008 lead NAAQS of 0.15 μg/m3. 

Table 6. Lyons Area’s 2011-2013 Design Values for the 2008 Pb NAAQS 

Site Name AQS Site ID 2011-2013

Design Values (μg/m3)

Lyons Boro 42-011-0021 0.05

Lyons Park 42-011-0022 0.04

D. CONCLUSIONS AND RECOMMENDED AGENCY ACTIONS

Consistent with the requirements in 40 CFR part 50, EPA has reviewed the Lyons Area 

ambient air monitoring data for Pb, and found that the highest 3-month mean concentration for 

2011-2013, that is the 2011-2013 design value for the Area, is less than 0.15 μg/m3. Thus, this 

finding supports EPA’s proposed determination that the Lyons nonattainment area has attained 

the 2008 Pb NAAQS, based on the most recent quality-assured, quality-controlled, and certified 

monitoring data for 2011-2013.