1

Technical Support Document

PUERTO RICO

Area Designations For the 

2008 Lead National Ambient Air Quality Standards

EPA has set the level of the primary (health-based) standard at 0.15 micrograms per cubic meter 

(μg/m3) measured as total suspended particles (TSP). EPA has set the secondary (welfarebased) standard to be identical in all respects to the primary standard.

Pursuant to section 107(d) of the Clean Air Act, EPA must designate as “nonattainment” 

those areas that violate the National Ambient Air Quality Standards (NAAQS) and those 

nearby areas that contribute to violations. The table below identifies the counties

1

or portions 

of counties in the Commonwealth of Puerto Rico that EPA is designating “nonattainment” for 

the 2008 lead national ambient air quality standard (2008 Lead NAAQS).

Table 1

Area

Puerto Rico Recommended 

Nonattainment County

EPA’s Designated 

Nonattainment County

Arecibo, Puerto Rico Arecibo, Puerto Rico (partial) Arecibo, Puerto Rico (partial)

Technical Analysis for Arecibo, Puerto Rico

Introduction 

This technical analysis for the Arecibo, Puerto Rico Area identifies a monitor in Arecibo County 

that violates the 2008 Lead NAAQS and evaluates nearby counties for contributions to lead

concentrations in the area. EPA has evaluated these counties based on the weight of evidence of 

the following factors recommended in previously issued EPA guidance: 

Air quality in potentially included versus excluded areas;

Emissions and emissions-related data in areas potentially included versus excluded from 

the nonattainment area, including population data, growth rates and patterns and 

emissions controls;

Meteorology (weather/transport patterns);

Geography/topography (mountain ranges or other air basin boundaries);

Jurisdictional boundaries (e.g., counties, air districts, reservations, etc.); and

Any other relevant information submitted to or collected by EPA.

 

1 For these purposes EPA considers the municipios of Puerto Rico to be equivalent to counties 

and for consistency and convenience will use the term “county.”
2

Figure 1: Sources in Arecibo County, Puerto Rico

Figure 1 is a map of the area analyzed showing the location of the air quality violating monitor in 

the area, Puerto Rico and EPA’s recommended “nonattainment” boundary, and the counties 

surrounding the violating air quality monitor. The violating monitor is located in Arecibo 

County in close proximity to The Battery Recycling Company, shown in Figure 1.

On October 14, 2009, Pedro J. Nieves Miranda, Chairman of Puerto Rico Environmental Quality 

Board, recommended that San Juan be designated as attainment, the Arecibo area be designated 

unclassifiable, and for the rest of Puerto Rico be designated unclassifiable/attainment for the 

2008 Lead NAAQS based on air quality data from 2006-2008. His recommendation was based 

on data from a Federal Reference Method (FRM) monitor located in the Commonwealth. EPA 

understands the recommendation for unclassifiable designation for the “Arecibo area” to refer to 

Arecibo County. Puerto Rico’s August 15, 2011 letter on Lead Designation for Arecibo revised

its recommendation based on recent 2010 data from a FRM monitor that had been operated by 

the Commonwealth showing a violation of the 2008 Lead NAAQS. The revised 

recommendation is for the area within the 4 km radius which surrounds The Battery Recycling 

Company facility in the Arecibo County to be designated nonattainment. 

Based on EPA's technical analysis described below, EPA is designating a portion of Arecibo 

County in Puerto Rico as nonattainment for the 2008 Lead NAAQS, based upon currently 

available information. This county is listed above in Table 1. Puerto Rico provided modeling 

results that showed a 4 km radius of The Battery Recycling Company in Arecibo County that 

could be impacted with daily high lead concentrations. In addition, Puerto Rico modeled 

monthly violations that extended up to 2 km from the source. In order to be conservative, based 
3

on the modeling, Puerto Rico recommended the nonattainment in Arecibo to include the area

within the 4 km radius of the source.

Detailed Assessment

Air Quality Data 

This factor considers the lead design values (in μg/m3) for air quality monitors in Arecibo 

County and the surrounding area based on data for the 2010 period. A monitor’s design value 

indicates whether that monitor attains a specified air quality standard. The 2008 Lead NAAQS 

are met at a monitoring site when the identified design value is valid and less than or equal to 

0.15 μg/m3. A design value is only valid if minimum data completeness criteria are met. A lead 

design value that meets the NAAQS is generally considered valid if it encompasses 36 

consecutive valid 3-month site means (specifically for a 3-year calendar period and the two 

previous months). For this purpose, a 3-month site mean is valid if valid data were obtained for 

at least 75 percent of the scheduled monitoring days in the 3-month period. A lead design value 

that does not meet the NAAQS is considered valid if at least one 3-month mean that meets the 

same 75 percent requirement is above the NAAQS. That is, a site does not have to monitor for 

three full calendar years in order to have a valid violating design value; a site could monitor just 

three months and still produce a valid (violating) design value.

The 2008 Lead NAAQS design values for Arecibo County and surrounding area are shown in 

Table 2.

Table 2. Air Quality Data

County Puerto Rico 

Recommended

Nonattainment?

Monitor 

Name

Monitor Air 

Quality 

System ID

Monitor 

Location

Lead Design 

Value, 

2007 – 2009

2

(μg/m3)

Lead Design 

Value, 

2008 – 20102

(μg/m3)

Arecibo 

County, 

PR

Yes Arecibo 720130001

Victor

Santoni 

Cordero

N/A 0.245

Arecibo County shows a violation of the 2008 Lead NAAQS. Therefore some area in Arecibo 

County and possibly additional areas in surrounding counties must be designated nonattainment. 

The absence of a violating monitor alone is not a sufficient reason to eliminate nearby counties 

as candidates for nonattainment status. Each area has been evaluated based on the weight of 

evidence of the eight factors collectively combined into five like groupings and other relevant 

information.

The violating monitor located in Arecibo County is located in close proximity to The Battery 

Recycling Company, Road No. 2 km 72.2 Barrio Cambalache in Arecibo, Puerto Rico. The 

monitoring objective, according to the EPA monitor locator report is “source-oriented”. The 

 

2

 Note: Monitoring did not start at this site until January 1, 2010.
4

emissions from The Battery Recycling Company will be discussed in the corresponding section 

below.

Emissions and Emissions-Related Data

Evidence of lead emissions sources in the vicinity of a violating monitor are an important factor 

for determining whether a nearby area is contributing to a monitored violation. For this factor, 

EPA evaluated county level emission data for lead and any growth in lead emitting activities.

Emissions

Emissions data for lead sources were derived from the 2008 National Emissions Inventory. See 

http://www.epa.gov/ttn/chief/net/2008inventory.html#inventorydoc. Some States and 

Commonwealth provided updated information on emissions and emission controls in their 

comments to EPA. Puerto Rico has provided updated 2009 emissions inventory information for 

the industrial sources. These data are provided in Table 3. The data provided by Puerto Rico 

was the most current emission information available at the time of their submittal. EPA 

recognizes that we have no information on any emissions increases that may have occurred since 

2009. For example, certain large sources of emissions in or near this area may have installed 

emission controls or otherwise significantly reduced emissions since 2009. 

Table 3 shows total emissions of lead sources emitting greater than 0.1 tons per year for the 

violating county according to the Puerto Rico 2009 Emissions Inventory. The airport located in 

Arecibo County emits less than 0.1 tons per year of lead based on 2008 NEI emissions inventory, 

and therefore, is not included in this table. Potentially contributing counties in and around the 

Arecibo area were also evaluated. However, there are no sources that can potentially emit 

greater than 0.1 ton per year of lead in neighboring counties. 

Table 3. Lead Emissions [Puerto Rico 2009 Supplied]

County Facility 

Located in 

Puerto Rico

Recommended 

Nonattainment 

Area?

Facility – Total 

Air Emissions 

[Information 

Source] (tons per 

year)

Facility 

Location

Distance 

from 

monitoring 

site

Total County 

Lead 

Emissions 

(tons per year)

Arecibo 

County, 

PR

Yes

The Battery 

Recycling 

Company 

1.22 tpy

Road No. 2, 

km 72.2, 

Barrio 

Cambalache, 

Arecibo

388 meters

1.385 tpy PREPA 

Cambalache 

Combustion 

Turbine Plant

0.165 tpy

PR 681, km 

0.5, Arecibo

1.5 

kilometers
5

Population Data, Growth Rates, and Patterns 

Table 4 shows the 2008 population for the county being evaluated. These data help assess the 

extent to which the concentration of human activities in the area and concentration of populationoriented commercial development may indicate emissions-based activity contributing to elevated 

ambient lead levels. This may include ambient lead contributions from activities that would 

disturb lead that has been deposited on the ground or on other surfaces. Re-entrainment of 

historically deposited lead typically is not reflected in the emissions inventory. 

Table 4. Population Data

County State 

Recommended 

Nonattainment?

2008 

Population

2008

Population 

Density 

(pop/sq mi)

Population 

Change 

2000-2008

Population 

% Change 

2000-2008

Arecibo 

County, 

Puerto 

Rico

Yes 102,643 801 2,273 2

Source of data: U.S. Census Bureau estimates for 2008 (http://www.census.gov/popest/datasets.html) and estimation 

of the area of U.S. Counties.

EPA has considered the population growth rate for this area and determined it does not affect the

nonattainment boundary.

Emissions Controls

Under this factor, the existing level of control of emission sources is taken into consideration. 

The emissions data used by EPA in this technical analysis and provided in Table 3 represent 

emissions levels taking into account any control strategies implemented on stationary sources in 

the Arecibo area before 2008. EPA has not received any additional information on emissions 

reductions resulting from controls put into place since 2008. The Battery Recycling Company is 

currently using one baghouse with an efficiency of 99.5% for its lead smelting furnace and five

molten lead refining kettle burners. The PREPA Cambalache facility is currently not using any 

control equipment for lead emissions for its three gas turbines.

Meteorology (weather/transport patterns)

For this factor, EPA considered data from National Weather Service instruments and other 

meteorological monitoring sites in the area. Wind speed and direction were analyzed from 

August 1992 to August 1993 for a meteorological site located in Cambalache, PR. 
6

Figure 2: Historic Wind Direction Frequency in each of Four Seasons for Arecibo County, 

Puerto Rico

As seen in Figure 2 above, on months with the highest observed lead levels, the prevailing 

surface winds were predominantly from the Northeast/Southeast.

Geography/topography (mountain ranges or other air basin boundaries)

The geography/topography analysis evaluates the physical features of the area that might have an 

effect on the air shed and, therefore, on the distribution of lead over the Arecibo Area. The 

terrain area that surrounds the Battery Recycling Company is a flat rural area with some elevated 

terrain at approximately 4 km to the southwest/southeast. 

Jurisdictional boundaries 

Existing jurisdictional boundaries may be helpful in articulating a boundary for purposes of 

nonattainment designations, and for purposes of carrying out the governmental responsibilities of 

planning for attainment of the lead NAAQS and implementing control measures. These existing 

boundaries may include an existing nonattainment or maintenance area boundary, a county or 

township boundary, a metropolitan area boundary, an air management district, or an urban 

planning boundary established for coordinating business development or transportation activities. 

The entire recommended nonattainment area is within Arecibo County. 
7

Other Relevant Information

On August 15, 2011, Puerto Rico conducted air dispersion modeling using the EPA 

recommended model AERMOD for the significant lead emission sources (Battery Recycling 

Company and PREPA Cambalache). Based on preliminary modeling, Puerto Rico found that the 

concentrations from PREPA Cambalache were negligible. This modeling showed a maximum 3 

month rolling average concentration from PREPA Cambalache of 0.000003 ug/m3. This value 

was so much below the standard that this facility was not included in the final modeling (See 

Table 3 for lead emissions for the facility). Accordingly, the final modeling only used the lead 

emissions from the Battery Recycling Company.

Modeling combines two of the factors discussed above, meteorology and emissions data, to 

estimate the area that would be above the standard. The lead emissions used in the modeling 

were recently submitted by the Battery Recycling during the permit process and were reviewed 

by the PREQB permit personnel.

Two types of emission sources were used to model the fugitive emissions, volume and area. The 

volume source option was used to model the fugitive emissions inside the main process building 

that the control equipment does not capture. The building was modeled as a volume source 

because it is not open completely like an area source. The initial lateral and vertical dimensions 

of the building and the center coordinates were determined through GPS. The area source was 

used to model the emissions generated from the vehicle movement between the carbon, scrap 

and soda ash storages. A fourteen-vertex polygon was created covering the area that the facility 

vehicles transit daily between these storages, approximately 4742 m2. This is a conservative 

scenario but it was the best modeling approximation of these fugitive emissions that could be 

used at this moment, with the available data. 

The facility is under construction and some changes have been made to the main process 

building and the storage areas that are not seen in the current aerial photos. 
8

Figure 3: Puerto Rico’s Lead Monthly Modeling Concentrations, Stack/Volume & Area Source

Puerto Rico provided modeling results that showed a 4 km radius of The Battery Recycling 

Company in Arecibo County that could be impacted with daily high lead concentrations. In 

addition, Puerto Rico modeled monthly violations that extended up to 2 km from the source. 

Accordingly, based on the modeling, Puerto Rico recommended the nonattainment in Arecibo to 

include the area within the 4 km radius of the source.

The modeling analysis submitted by Puerto Rico can be found in the docket for the designations, 

PR lead modeling analysis.pdf.

Conclusion

After considering the factors described above, EPA has determined that it is appropriate to 

include a portion of Arecibo County in Puerto Rico as nonattainment for the 2008 Lead NAAQS, 

specifically the area within four kilometers of the boundaries of the Battery Recycling Company 

facility.

EPA based this nonattainment designation determination and boundary on the fact that Arecibo 

County contains an air quality monitor that shows a violation of the 2008 Lead NAAQS, based 

on 2010 air quality data, and Puerto Rico’s August 15, 2011 letter on Lead Designation for 

Arecibo. The Battery Recycling Company facility is the largest emissions source located upwind 

of the violating monitor, and EPA and Puerto Rico believe this facility caused and/or contributed 

to the violating monitor during the period.

Based on its considerations of all the relevant, available information, as described above, EPA 

believes that the boundaries described herein encompass the entire area that does not meet (or 

that contributes to ambient air quality in a nearby area that does not meet) the 2008 Lead 

NAAQS.
9

Definition of important terms used in this document:

1) Designated “nonattainment” area – an area which EPA has determined, based on a State 

recommendation and/or on the technical analysis included in this document, has violated the 

2008 Lead NAAQS, based on the most recent three years of quality assured air quality 

monitoring data from 2008-2010 including at least one valid three-month site mean above the 

level of the 2008 Lead NAAQS, or that contributes to a violation in a nearby area. 

2) Designated “unclassifiable/attainment” area – an area which EPA has determined does not 

contribute to a violation of the 2008 Lead NAAQS in a nearby area and either: (1) meets the 

2008 Lead NAAQS, based on the most recent three years of quality assured air quality 

monitoring data from 2008-2010 including 36 consecutive valid three-month site means 

(including the last two months of 2007), or (2) has no monitors or has incomplete air quality 

monitoring data for 2008-2010 but has no violations of the 2008 Lead NAAQS.

3) Designated “unclassifiable” area – an area which EPA has determined cannot be classified 

on the basis of available information as meeting or violating the 2008 Lead NAAQS, based on 

the most recent three years of quality assured air quality monitoring data from 2008-2010, but for 

which available monitoring data from the same or a recent period indicate a significant 

likelihood that the area may be violating the 2008 Lead NAAQS.

4) Prior nonattainment area – an area that was previously designated as nonattainment for the 

1978 Lead Standard (including both current nonattainment areas and maintenance areas).

5) Recommended nonattainment area – an area a State or Tribe has recommended to EPA be 

designated as nonattainment.

6) Violating monitor – an ambient air monitor whose valid design value exceeds 0.15 

micrograms per cubic meter (ug/m3). As described in Appendix R of part 50, a violation can be 

based on either Lead-TSP or Lead-PM10 data and only three months of data are necessary to 

produce a valid violating design value. 

7) 1978 Lead NAAQS – 1.5 μg/m3, National Ambient Air Quality Standard for lead 

promulgated in 1978. Based on Lead-TSP indicator and averaged over a calendar quarter.

8) 2008 Lead NAAQS - 0.15 μg/m3, National Ambient Air Quality Standard for lead 

promulgated in 2008. Based on Lead-TSP indicator and a three-month rolling average. LeadPM10 data may be used in limited instances, including to show nonattainment.