Commonwealth of Puerto Rico 

Puerto Rico Environmental Quality Board 

Puerto Rico Area Designation for the Revised Lead 

National Ambient Air Quality Standard

October 14, 2009
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TABLE OF CONTENTS

Table of Contents....................................................................................................... 2 

Acronyms and Abbreviations ..................................................................................... 3 

Executive Summary................................................................................................... 4 

AREA DESIGNATION ............................................................................................... 5 

1) San Juan Area ................................................................................................ 5 

Procedure and results from San Juan Area........................................................ 6 

2) Arecibo Designations ...................................................................................... 7 

3) Other Areas Designations ............................................................................... 7 

Conclusion ................................................................................................................. 7 

Appendix I: Design Value calculations 3 month Rolling Average............................... 8 
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ACRONYMS AND ABBREVIATIONS

AIRS: Aerometric Information Retrieval System 

CAA: Clean Air Act 

CFR: Code Federal Register 

CPR: Commonwealth of Puerto Rico 

EPA: Environmental Protection Agency 

EQB: Environmental Quality Board 

FRM: Federal Reference Method 

NAAQS: National Air Ambient Quality Standards 

PB: Lead 

PR: Puerto Rico 

PREQB: Puerto Rico Environmental Quality Board 

TSP: Total Suspended Particulate 

μg/m3: unit, micrograms per cubic meter 
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EXECUTIVE SUMMARY

Section 109(d)(1) of the Clean Air Act (CAA) requires the Environmental Protection 

Agency (EPA) to complete through review of the National Ambient Air Quality 

Standards (NAAQS) on 5 year intervals using the criteria published on section 108 

of the CAA. In accordance with such requirements on October 15, 2009, EPA 

revised the Lead NAAQS. The new primary lead standard was lowered from the 1.5 

micrograms per cubic meter (μg/m3) level set in 1978, to a level of 0.15 μg/m3 based 

on a quarterly averaging time. The reason for the change was to provide increased 

protection against lead-related welfare effects. 

Section 107(d) (1) (A) of the Clean Air Act (CAA) establish the process for area 

designations following the establishment of a new revised NAAQS. Under this 

section, States are required to submit recommendations to EPA not later than one 

year after the promulgation of a new or revised standard. The areas must be 

classify as attainment, nonattainment, or unclassifiable with respect to the new or 

revised standard. The recommendations must be submitted to EPA by October 15, 

2009. 

The Environmental Quality Board (EQB) is responsible for developing and 

implementing emission control programs for attaining and maintaining the NAAQS. 

As required by section 107(d), the Commonwealth of Puerto Rico (CPR) is 

submitting the designations and recommendations for the new revised lead standard

for EPA approval. In this document EQB is providing the list of designations 

recommendations for all areas in CPR base on available information on existing 

monitoring data and will be waiting for designation of the newly lead monitoring 

station are available. 
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AREA DESIGNATION 

1) San Juan Area 

The designation of the San Juan area is base on available monitoring data from 

monitoring station located at the Baldorioty Avenue, which is identified with the AIRS 

Number 72-127-0003. The lead and its compounds are measured as elemental lead 

in total suspended particulate (Pb-TSP), sampled and analyzed by a Federal 

Reference Method (FRM) in 40 Code of Federal Regulations Part 50 Appendix G – 

High Volume TSP. 

The site was designed to account for geographic size, population density, complexity 

of terrain, meteorology, and to measured air quality to compare with the primary 

NAAQS for lead and to record the highest concentration in the area. The San Juan 

municipality has the Luis Muñoz Marin International Airport and EQB already has a 

lead monitor in the area. The EQB evaluated the quality assured, certified air quality 

data for the most recent three consecutive year period that includes the years 2005 

to 2008, and determined that the data obtained do not exceed the revised lead 

NAAQS. 

Figure 1 – Actual Lead Monitoring Network- San Juan
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Procedure and results from San Juan Area 

The Pb NAAQS is met at a monitoring site when the identified design value is valid 

and less than or equal to 0.15 micrograms per cubic meter (μg/m3). In accordance 

with 40 CFR Part 50 final version of Appendix R provides that the 3-month averages 

which include either of the two months prior to a three-calendar-year period will be 

associated with that 3-year period, and that the 3-month averages which include 

either of the two months after the three calendar year period will not be associated 

with it. The latter two months would be within the next 3-year period and their data 

would affect compliance during that next 3-year period. 

The Pb sampling for San Juan has a schedule to take a sample every sixth day. The 

procedure approach to demonstrate attainment and calculate the design value is as 

follow: 

1. Is average all scheduled, make-up, and extra samples taken on a given 

scheduled sample, typically, there will be up to five such 6-day averages in a 

month; there can be fewer 6-day averages if one or more of the 6-day periods 

yielded no valid data. 

2. Is average these 6-day averages together to calculate the monthly average. 

This approach has the effect of giving equal weight to each 6-day period 

during a month regardless of how many samples were actually obtained 

during the 6 days, which mitigates the potential for the monthly average to be 

distorted. 3. 

3. Calculating the 3-month average would be to average the three monthly 

averages giving equal weight to each month, as described above in the 

standard 2-step approach to calculating the 3-month mean. 

4. Also, Puerto Rico applies the 75 percent completeness requirement at the 3-

month level by averaging the three monthly completeness values to get the 3-

month completeness value. This reduces the likelihood of an incompleteness 

situation for an entire 3-year evaluation period due to as few as two missed 

samples in a single month. The data substitution was applied in some 

individual month that has incomplete data relative to the 75 percent 

requirement. The data are still substituted within the individual month (i.e., if a 

day of concentration data is missing from January in one of the three years, 

the missing concentration is substituted with the highest available measured 

Pb concentration from other days in the three Januarys). Finally the 

comparison of the substituted average concentration to the level of the 

NAAQS is done for the 3-month average concentration not the monthly 

average concentration since a 3-month averaging time has been selected. 

5. Comparison the identified design value with the 0.15 μg/m3 to determine if 

meets the NAAQS. 
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According with the results, San Juan meets the primary Pb standards. The highest 

valid 3-month site-level mean over the most recent 38-month period concentration1

is 0.049 μg/m3 that is less than 0.15 μg/m3. The average percent of days within the 

required monitoring with valid ambient monitoring data is greater than 75 % data 

completeness. Therefore the data completeness requirement is also met. 

2) Arecibo Designations 

According with the Pb emissions inventory the Arecibo area was identified with the 

potential to emit 1 ton of lead a year. EQB recommend establishing a newly 

monitoring station as part of the lead air quality monitoring network 2009. On 

January 1, 2010 should be installed and operational. The EQB intend to make 

designation when the necessary from the newly station is available. 

3) Other Areas Designations 

The Pb emissions inventory for Puerto Rico demonstrate that the rest areas in 

Puerto Rico do not have industries with the potential to emit 1 ton of lead a year or 

have more than 500,000 people. According with that the rest of Puerto Rico should 

be designated as unclassified/attainment. 

CONCLUSION

Based on the technical documents and to the most recent data the following are the 

designations and recommendations for the new revised lead NAAQS in Puerto Rico: 

- attainment for the San Juan area base on existing monitoring data; 

- unclassified for the Arecibo area until sufficient air quality data from the newly 

lead monitoring station are available to take final action. 

- unclassified/attainment for the rest of the areas in Puerto Rico because 

sufficient monitoring data is not available to make a determination and the 

emissions sources located at this areas are below one (1) ton/yr.

 

1

 See Table1 - 3-month site
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APPENDIX I: DESIGN VALUE CALCULATIONS 3 MONTH ROLLING AVERAGE 

Oct 2005 to Sept. 2008 

AIRS Number 72-127-0003 

Baldorioty Ave. at San Juan, Puerto Rico 

Month Period Design Value by 

3-month 

Oct/ 2005 0.006 

Nov/ 2005 0.008 

Dec/ 2005 0.007 

Jan / 2006 0.006 

Feb / 2006 0.004 

Mar / 2006 0.000 

Apr / 2006 0.000

May / 2006 0.000

Jun / 2006 0.000

Jul / 2006 0.000

Aug / 2006 0.000

Sep / 2006 0.000

Oct / 2006 0.000 

Nov/ 2006 0.003 

Dec/ 2006 0.006 

Jan / 2007 0.010 

Feb / 2007 0.007 

Mar / 2007 0.004 

Apr / 2007 0.000 

May / 2007 0.000

Jun / 2007 0.000

Jul / 2007 0.000

Aug / 2007 0.005 

Sep / 2007 0.009 

Oct / 2007 0.011 

Nov/ 2007 0.011 

Dec/ 2007 0.017 

Jan / 2008 0.033 

Feb / 2008 0.044 

Mar / 2008 0.049 

Apr / 2008 0.036 

May / 2008 0.022 

Jun / 2008 0.011 

Jul / 2008 0.010 

Aug / 2008 0.010 

Sep / 2008 0.010 

Max Rolling Ave. 0.049 
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