Mercury Spring Hill Modeling Report

ASSESSMENT OF PROPOSED CREMATORY EMISSIONS

SPRING HILL MEMORIAL PARK AND FUNERAL HOME 5239 MAIN STREET

SPRING HILL, TENNESSEE 37174

EnSafe Project Number

0888811171

Prepared for:

THE CITY OF SPRING HILL 199 TOWN CENTER PARKWAY

SPRING HILL, TENNESSEE 37174

Prepared by:

EnSafe Inc. 220 Athens Way, Suite 410

Nashville, Tennessee 37228 (615) 255-9300 (800) 588-7962

www.ensafe.com

November 2011

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Table of Contents

1.0 INTRODUCTION ............................................................................................................ 1

2.0 APPROACH ................................................................................................................... 4

3.0 DISPERSION MODELING ................................................................................................ 6 3.1 Methodology ...................................................................................................... 6

3.1.1 General Modeling Approach ...................................................................... 6 3.1.2 Emission Rate Calculation ......................................................................... 6 3.1.3 Meteorological Data ............................................................................... 11 3.1.4 Receptors and Terrain ............................................................................ 11 3.1.5 Emission Source .................................................................................... 11 3.1.6 Building Downwash ................................................................................ 15

3.2 Modeling Results .............................................................................................. 15

4.0 COMPARISON OF PREDICTED CONCENTRATIONS WITH SCREENING LEVELS .................. 16 4.1 Screening Level Selection .................................................................................. 16

4.1.1 Sources of Screening Levels Considered ................................................... 16 4.1.2 Discussion and Selection of Long-term Screening Levels ............................ 17 4.1.3 Discussion and Selection of Short-term Screening Levels ........................... 17

4.2 Comparison of Predicted Ambient Air Concentrations with Selected Screening Levels .............................................................................................................. 18

5.0 DISCUSSION OF RESULTS ........................................................................................... 23

6.0 CONCLUSIONS ............................................................................................................ 24

7.0 REFERENCES .............................................................................................................. 25

Figures

Figure 1 Facility Location — Topographic Map .................................................................... 2 Figure 2 Facility Location — Aerial View ............................................................................. 3 Figure 3 Receptor Grid ................................................................................................... 12 Figure 4 Receptor Grid — Near Facility ............................................................................ 13 Figure 5 Facility Layout .................................................................................................. 14

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Tables

Table 1 Crematory Emission Rates for Mercury, Dioxins and Furans Identified in the Scientific Literature ........................................................................................................... 7

Table 2 Facility Emission Rates and Source Parameters ................................................... 15 Table 3 Sources of Screening Levels Considered for Long-Term Exposure Analysis ............. 16 Table 4 Modeling Results and Comparisons to Risk-Based Screening Levels ....................... 19

Appendices

Appendix A Emission Rate Calculations Appendix B Modeling Files and Descriptions

Assessment of Proposed Crematory Emissions Spring Hill Memorial Park and Funeral Home

Spring Hill, Tennessee November 2011

1

1.0 INTRODUCTION

EnSafe was engaged by the City of Spring Hill, Tennessee to review and document relevant

scientific, engineering and public health information — including potential air quality impacts,

to facilitate the City’s evaluation of a crematory proposed for construction by Spring Hill Memorial

Park and Funeral Home (Spring Hill Memorial) located at 5239 Main Street, Spring Hill, Tennessee.

The proposed facility location is shown on Figure 1. An aerial view of the facility is shown on

Figure 2.

In Phase 1 of this project, EnSafe researched the published scientific literature and regulatory

studies related to crematories, gathered information regarding the cremation process, and

estimated the potential emissions from the proposed crematory. The findings of that first phase

were summarized in the EnSafe report issued to the City of Spring Hill titled, Air Emissions from

Potential Spring Hill Crematory, September 2011.

Subsequent to the issuance of the aforementioned report, the Spring Hill Board of Mayor and

Aldermen (BOMA) requested that EnSafe proceed with the second and third phases of the project

which were (Phase 2) to perform an air dispersion modeling analysis using an appropriate

U.S. Environmental Protection Agency (USEPA) air dispersion model and emission rates for

mercury, dioxins and furans to predict the ambient air quality impacts from crematory emissions,

and (Phase 3) to use the air dispersion modeling results from Phase 2 to evaluate the predicted

airborne pollutant concentrations regarding their potential public health effects. This report

summarizes the results of the Phase 2 and Phase 3 analyses.

The pollutants mercury, total dioxins and total furans were selected for this analysis for

two reasons. The first is that in order for the proposed crematory to begin construction, and

subsequently operation, Spring Hill Memorial must obtain an air quality permit from the Tennessee

Department of Environment and Conservation — Division of Air Pollution Control (TDAPC) and that

permit will limit emissions of particles (soot) and visible emissions (smoke) to levels considered by

TDAPC to meet ambient air quality standards. Primary and secondary ambient air quality standards

define levels of air quality that are believed to be adequate, with an appropriate margin of safety,

to protect public health and welfare. The second is that of the remaining pollutants likely to be

emitted from the crematory, based on discussions with the BOMA and comments by members of

the public during BOMA meetings, it is apparent that mercury, dioxins and furans are the primary

pollutants of public health concern. A full list of the potential air pollutants from the proposed

crematory are discussed in EnSafe’s September 2011 report.

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Basemap Source: USGS Godwin, Tennessee Quadrangle Topographic Maphttp://services.arcgisonline.com/arcgis/services/USA_Topo_Maps

© 2011 National Geographic Society, i-cubed

Figure 1Assessment of Proposed Crematory Emissions

Facilty Location - Topographic MapSpring Hill Memorial Park & Funeral Home

Spring Hill, Tennessee

0 850 1,700 2,550 3,400Feet

Date: 11/8/2011DRAWN BY:

J. AslingerREQUESTED BY:

0888811171PROJECT NO:

M. Senne(615) 255-9300

WWW.ENSAFE.COMNASHVILLE, TN

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Facilty Location - Aerial ViewSpring Hill Memorial Park & Funeral Home

Spring Hill, Tennessee

0 120 240 360 480Feet

Date: 11/8/2011DRAWN BY:

J. AslingerREQUESTED BY:

0888811171PROJECT NO:

M. Senne(615) 255-9300

WWW.ENSAFE.COMNASHVILLE, TN

Basemap Source: Esri World Imageryhttp://services.arcgisonline.com/arcgis/services/World_Imagery

© 2011 Esri, i-cubed, USDA FSA, USGS, AEX, GeoEye, AeroGRID, Getmapping, IGP

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4

2.0 APPROACH USEPA’s air dispersion model, AMS (American Meteorological Society) and EPA Regulatory MODel,

AERMOD (version 11103) was used to predict ambient air concentrations of mercury, dioxins and

furans in the area surrounding the proposed crematory.

AERMOD was used to predict both long-term (chronic) and short-term (acute) ambient air

concentrations of mercury, and the long-term ambient air concentrations of dioxins and furans.

No short-term ambient air concentration was predicted for dioxins and furans because there is

no short-term screening level available for comparison to the predicted concentrations.

The long-term concentrations were based on predicted maximum annual average ambient air

concentrations of each pollutant. Two types of short-term ambient air concentrations were

analyzed for mercury. These were based on the predicted maximum hourly concentration and

the predicted maximum 8-hour average concentration of each pollutant. In both the long-term and

short-term analysis, with regard to mercury, both the USEPA emission rates and the highest

reported mercury content emission rates were modeled.

For the purposes of predicting long-term ambient air concentrations, it was assumed that

the average cremation takes three hours (half hour for warm-up, two hours for the cremation, and

half hour cool-down) and that a cremation would occur at the proposed Spring Hill Memorial

crematory every three hours throughout the year. That is, that there would be approximately

2,920 cremations performed per year, which is roughly ten times the number of cremations

planned according to Ms. Pam Stephens of Spring Hill Memorial (Pam Stephens,

Personal Communication, August 31, 2011). This was done to provide an added level of

conservatism to the long-term impact analysis.

For the purposes of predicting short-term ambient air concentrations of mercury, it was assumed

that all the mercury in the body being cremated is emitted in only one of the three hours of

the cremation. This, too, was done to provide an added level of conservatism to the analysis and

because it has been reported, based on studies done in Japan, that most of the mercury in

the body is emitted in the first hour of the cremation process (Draft Report, Crematory Toxic

Emissions Inventories, Risk Assessments, and Risk Reduction Measures, David Craft, Monterey Bay

(California) Unified Air Pollution Control District, et al, July 2011, p. 11).



5

The predicted long-term ambient air concentrations of dioxins and furans as well as the long and

short-term ambient air concentrations of mercury in the vicinity of the proposed crematory were

then compared to published screening levels for each pollutant. In addition, at the request of

the BOMA, predicted ambient air concentrations of these pollutants at select locations in

the community, such as neighborhoods, parks, schools and churches, were also compared to

the same screening levels. These comparisons are shown in Table 4 and discussed in detail in

Section 4.0 of this report.



6

3.0 DISPERSION MODELING

3.1 Methodology

The following methodology was followed in accordance with general USEPA and TDAPC

modeling guidance.

3.1.1 General Modeling Approach

As stated earlier USEPA’s air dispersion model, AERMOD (version 11103) was used for this analysis

since it is the preferred model listed in USEPA’s Guideline on Air Quality Models. AERMOD handles

all types of terrain and also includes building downwash and cavity impact evaluations which were

judged to be important in this analysis. Default model options were used, including the rural

setting since the 3-kilometer area immediately surrounding the facility is predominately rural.

3.1.2 Emission Rate Calculation

There is a wide range of emission rates for mercury, dioxins and furans emissions from crematories

discussed in the scientific literature. Table 1 summarizes those emission rates identified by EnSafe

during Phase 1 of this project.

As discussed in EnSafe’s September 2011 report, USEPA maintains an extensive database of

recommended emission factors for a wide range of air pollutants from many types of air emission

sources. These emission factors are provided in USEPA’s Factor Information Retrieval System

(FIRE) database. These factors are used extensively by federal, state and local regulators for

estimating potential air quality impacts from new sources of air pollutants. As also discussed in

EnSafe’s September 2011 report, the most extensive regulatory guidance for permitting crematories

found by EnSafe is the Bay Area Air Quality Management District (BAAQMD) Permit Handbook,

which recommends the use of emission factors from the USEPA FIRE database in conducting

assessments of air quality impacts from crematories in the San Francisco Bay area of California.

For these reasons, the primary emission rates for mercury, dioxins and furans used in this

dispersion modeling analysis were developed from emission factors from the FIRE database.

In addition to these USEPA emission rates, and in order to provide the most conservative air quality

impact analysis possible, an emission rate for mercury was also developed from the highest

mercury body content found in the published literature search conducted by EnSafe during Phase 1

of this project. That emission rate indicated a mercury content of 8.6 grams per body (g/body)

(Summary of References on Mercury Emissions from Crematoria, John Reindl, November 2008,

p. 7). By comparison, the USEPA mercury emission factor is based on a mercury content of roughly

1.5 g/body. Assuming an average mercury content of 0.5 g/silver dental amalgam,

these two emission rates relate to an average of approximately 17 and 3 silver dental amalgams

per body, respectively.



7

Table 1 Crematory Emission Rates for Mercury, Dioxins and Furans Identified in the Scientific Literature

Long-Term Mercury

Emission Rate1

(grams/sec)

1-Hour Mercury

Emission Rate2

(grams/sec)

8-Hour Mercury Emission Rate3

(grams/sec)

Long-Term Dioxin

Emission Rate1

(grams/sec)

Long-Term Furan

Emission Rate1

(grams/sec) Reference

1.38E-044 4.15E-04 1.55E-04 9.87E-10 1.48E-09 Based on EPA FIRE Database

7.50E-05 1.50E-04 2.81E-05 Based on CANA/EPA Test at Woodlawn Mortuary in 1999 — average of 3 runs made with cremation unit operating at 1400O F



1.03E-13 Based on Dioxins and Furans in Australia: Air Emissions, May 2002, Page 38, Chapter 6.1.9, Crematoria

1.03E-13 Based on Dioxins and Furans in Australia: Air Emissions, May 2002, Page 38, Chapter 6.1.9, Crematoria

8.71E-07 2.61E-06 9.79E-07 Based on low end of range of mercury per body (0.0094 grams) as reported in unpublished draft report Summary of References on Mercury Emissions from Crematoria, November 3, 2008

7.96E-04 2.39E-03 8.96E-04 Based on high end of range of mercury per body (8.6 grams) as reported in unpublished draft report Summary of References on Mercury Emissions from Crematoria, November 3, 2008

5.18E-09

Based on Characterizing the Emissions of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans from Crematories and Their Impacts to the Surrounding Environment, Environmental Science & Technology, 2003, 37, pp 62-67

5.18E-09

Based on Characterizing the Emissions of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans from Crematories and Their Impacts to the Surrounding Environment, Environmental Science & Technology, 2003, 37, pp 62-67

4.62E-05 1.39E-04 5.20E-05

Based on 0.0011 lbs of mercury per body burned from

Amendment to County General Ordinance Code Sections 6.20.30 and 17.52.580 RE: Crematoria, County of Alameda CA, August 2010

2.94E-04 8.82E-04 3.31E-04 Proposed emission rate for Colorado based on a study done by Tetra Tech, Pollution Prevention Crematoria Project Final Report, June 2007



8


Long-Term Mercury

Emission Rate1

(grams/sec)

1-Hour Mercury

Emission Rate2

(grams/sec)


(grams/sec)

Long-Term Dioxin

Emission Rate1

(grams/sec)

Long-Term Furan

Emission Rate1


1.09E-04 3.28E-04 1.23E-04

Proposed emission factor from Emission Factor Development For Mercury Emissions from Crematoria for Application to Facilities in Minneapolis, Minnesota prepared by Barr Engineering Company, March 14, 2008 based on EPA/CANA Test at Woodlawn Crematorium

3.33E-04 1.00E-03 3.75E-04

Low end of range of emission factors from Sweden based on numbers of dental amalgams per body cremated as reported in Emission Factor Development For Mercury Emissions from Crematoria for Application to Facilities in Minneapolis, Minnesota prepared by Barr Engineering Company, March 14, 2008

5.46E-04 1.64E-03 6.14E-04

High end of range of emission factors from Sweden based on numbers of dental amalgams per body cremated as reported in Emission Factor Development For Mercury Emissions from Crematoria for Application to Facilities in Minneapolis, Minnesota prepared by Barr Engineering Company, March 14, 2008

4.62E-04 1.39E-03 5.20E-04

Emission factor from Swedish EPA based on numbers of dental amalgams per body cremated as reported in Emission Factor Development For Mercury Emissions from Crematoria for Application to Facilities in Minneapolis, Minnesota prepared by Barr Engineering Company, March 14, 2008

1.85E-04 5.54E-04 2.08E-04

Low end of range of emission factors from Norway based on numbers of dental amalgams per body cremated as reported in Emission Factor Development For Mercury Emissions from Crematoria for Application to Facilities in Minneapolis, Minnesota prepared by Barr Engineering Company, March 14, 2008



9


Long-Term Mercury

Emission Rate1

(grams/sec)

1-Hour Mercury

Emission Rate2

(grams/sec)


(grams/sec)

Long-Term Dioxin

Emission Rate1

(grams/sec)

Long-Term Furan

Emission Rate1


4.54E-04 1.36E-03 5.10E-04

High end of range of emission factors from Norway based on numbers of dental amalgams per body cremated as reported in Emission Factor Development For Mercury Emissions from Crematoria for Application to Facilities in Minneapolis, Minnesota prepared by Barr Engineering Company, March 14, 2008

2.15E-04 6.45E-04 2.42E-04

Low end of range of emission factors from Switzerland based on numbers of dental amalgams per body cremated as reported in Emission Factor Development For Mercury Emissions from Crematoria for Application to Facilities in Minneapolis, Minnesota prepared by Barr Engineering Company, March 14, 2008

4.12E-04 1.23E-03 4.63E-04

High end of range of emission factors from Switzerland based on numbers of dental amalgams per body cremated as reported in Emission Factor Development For Mercury Emissions from Crematoria for Application to Facilities in Minneapolis, Minnesota prepared by Barr Engineering Company, March 14, 2008

2.68E-04 8.05E-04 3.02E-04

Average emission factor from Canada based on numbers of dental amalgams per body cremated as reported in Emission Factor Development For Mercury Emissions from Crematoria for Application to Facilities in Minneapolis, Minnesota prepared by Barr Engineering Company, March 14, 2008

4.54E-05 1.36E-04 5.10E-05

Low end of range of emission factors from UK based on numbers of dental amalgams per body cremated as reported in Emission Factor Development For Mercury Emissions from Crematoria for Application to Facilities in Minneapolis, Minnesota prepared by Barr Engineering Company, March 14, 2008



10


Long-Term Mercury

Emission Rate1

(grams/sec)

1-Hour Mercury

Emission Rate2

(grams/sec)


(grams/sec)

Long-Term Dioxin

Emission Rate1

(grams/sec)

Long-Term Furan

Emission Rate1


2.77E-04 8.32E-04 3.12E-04

High end of range of emission factors from UK based on numbers of dental amalgams per body cremated as reported in Emission Factor Development For Mercury Emissions from Crematoria for Application to Facilities in Minneapolis, Minnesota prepared by Barr Engineering Company, March 14, 2008

Notes: 1 Based on a 3-hour cremation process — 0.5 hour warm-up, 2-hour cremation, and 0.5 hour cool down. 2 Based on all the mercury in the body being emitted in the first of the three hours of the cremation process. 3 Based on all the mercury in the body being emitted in the first hour of the cremation process and cremations occurring consecutively every three hours.

Thus in an 8-hour period the maximum possible number of hours in which mercury emissions occur is three. 4 Scientific notation (e.g., 2.2E-06) is used extensively in this report.



11

The description of the development of the specific emission rates used in the analysis along

with emission rate calculations for the proposed facility are provided in detail in Appendix A of

this report.

3.1.3 Meteorological Data

USEPA recommends the use of five years of meteorological data from a nearby, representative

National Weather Service (NWS) site or at least one year of on-site collected data for use in

dispersion modeling studies. Since there is no on-site data available, the nearest NWS site with

appropriate data collected is at the Nashville International Airport.

Five years of surface and upper air meteorological data from Nashville, Tennessee were obtained

and processed with the USEPA program AERMET (version 11059). The data set for years 2006

through 2010 were evaluated but did not have enough complete data for use in dispersion

modeling. Thus, the five most recent meteorological data years for the analysis are 2001 through

2005. Surface parameters required for AERMET were calculated using the USEPA program

AERSURFACE (version 08009) by evaluating land use in the 1 kilometer area surrounding

the Nashville NWS site. A profile base of 600 feet is used in the analysis.

3.1.4 Receptors and Terrain

The receptor grid was developed following modeling guidelines. A 25-meter spaced grid was used

along the facility property line. A 50-meter spaced grid was used out to 500 meters from

the facility, 100-meter spacing out to 2.5 kilometers, 500-meter spacing out to 5 kilometers, and

1-kilometer spacing out to 10 kilometers. In addition to this grid, discrete receptors were added to

represent several locations of special interest to the community, including nearby neighborhoods,

parks, churches, and schools. The receptor grid, in UTM NAD27, is shown on Figures 3 and 4.

All receptor elevations and critical hill heights were calculated from a seamless, 1/3 arc second NED

data file using the USEPA program AERMAP (version 11103).

3.1.5 Emission Source

The modeling analysis evaluated emissions from the proposed crematorium stack. The source base

elevation was set to the same as the building base elevation as extracted by AERMAP. The facility

source location, in UTM NAD27, is shown on Figure 5. The stack diameter, stack temperature,

stack exit velocity and stack height above the roof line were provided by the cremation unit vendor,

Matthews Cremation, and are based on actual measurements made under operating conditions

during stack testing of the same cremation unit model Spring Hill Memorial plans to purchase

(email from Eduardo Romero to John Shipp, October 20, 2011). The source parameters and

emission rates are summarized in Table 2.



12

Figure 3 Receptor Grid

496000 498000 500000 502000 504000 506000 508000 510000 512000 514000 5160003946000

3948000

3950000

3952000

3954000

3956000

3958000

3960000

3962000

3964000

3966000



13

Figure 4 Receptor Grid — Near Facility

UTM meters NAD27

505600 505800 506000 506200 506400 506600 506800 507000 507200 5074003955800

3956000

3956200

3956400

3956600

3956800

3957000

3957200

3957400

3957600

Nearby Neighborhood

First Baptist

Harvey Park

Presbyterian Church Children's Home

Elementary School

Evens Park



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Figure 5 Facility Layout

UTM NAD27

506350 506400 506450 506500 506550 506600 506650 506700 5067503956550

3956600

3956650

3956700

3956750

3956800

3956850

3956900

Existing Building

Proposed Building

Stack



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Table 2 Facility Emission Rates and Source Parameters

Parameter Values

Stack Height 8.84 m (29 ft)

Stack Diameter 0.51 m (1.67 ft)

Stack Temperature 922 K (1200 °F)

Stack Exit Velocity 6.1 m/s (20 ft/s)

UTM Coordinates NAD27

Horizontal (E) 506,556.1 m

Vertical (N) 3,956,695.8 m

Stack Base Elevation Above MSL b (m) 228.69 m

Mercury: USEPA Emission Rate — 1-hour/Acute 4.15E-04 g/s

Mercury: Max Emission Rate — 1-hour/Acute 2.39E-03 g/s

Mercury: USEPA Emission Rate — 8-hour/Acute 1.55E-04 g/s

Mercury: Max Emission Rate — 8-hour/Acute 8.96E-04 g/s

Mercury: USEPA Emission Rate — Annual/Chronic 1.38E-04 g/s

Mercury: Max Emission Rate — Annual/Chronic 7.96E-04 g/s

Total Dioxins USEPA Emission Rate 9.87E-10 g/s

Total Furans USEPA Emission Rate 1.48E-09 g/s

Notes: a Stack height above ground level. b MSL = mean sea level. c Scientific notation (e.g., 2.2E-06) is used extensively in this report.

Due to the extremely low emission rates for dioxins and furans, the modeling for these pollutants

was evaluated using a single run with a “unitized” emission rate of 1 gram per second.

The resulting unitized concentrations were then multiplied by the emission rate to produce the final

results for each compound.

3.1.6 Building Downwash

The facility’s existing and proposed buildings and emission source were entered into

the BPIP-PRIME model (version 04274) in order to include building downwash in the modeling

analysis. The facility layout, in UTM NAD27, is shown on Figure 5. The proposed building and

stack base elevations were set to the same as the existing building base elevation as extracted

by AERMAP.

3.2 Modeling Results

The results of the modeling analysis are discussed in detail in Section 4.0 and summarized in

Table 4 along with comparisons of the results with selected screening levels. A listing of

the modeling files and their descriptions are included in Appendix B.



16

4.0 COMPARISON OF PREDICTED CONCENTRATIONS WITH SCREENING LEVELS

4.1 Screening Level Selection

The purpose of the risk screening process is to determine whether the emissions of mercury,

dioxins and furans from the proposed crematory pose a risk to human health by comparing

predicted ambient air concentrations to appropriate screening levels for air. Since the proposed

crematory is located near residential areas, residential land use was assumed when selecting

the appropriate screening levels. Therefore, potential exposure was evaluated by selecting

screening levels that consider the inhalation of contaminants through air in a residential setting and

assuming exposure would occur over a lifetime.

4.1.1 Sources of Screening Levels Considered

Many sources of screening levels were considered for this analysis, including the Agency for

Toxic Substances and Disease Registry (ATSDR) minimal risk levels (MRLs), USEPA Average Daily

Intake (ADI) from their Dioxin Reassessment report, USEPA Regional Screening Levels (RSLs),

World Health Organization (WHO) Time-Weighted Averages, California Office of Environmental

Health Hazard Assessment (OEHHA) Reference Exposure Levels (RELs), the U.S. Code of Federal

Regulations (CFR), and others (see Section 7.0 for summary of references).

Environmental screening levels are available for dioxins and mercury in the sources above, but

none are available for furans. Some furans are toxicologically similar to dioxins, so many guidance

documents recommend using the same screening levels for dioxins and furans. Therefore, for

the purposes of this analysis, the predicted ambient air concentrations of furans were compared to

the screening levels for dioxins. Screening levels considered for long-term exposure are

summarized in Table 3.

Table 3 Sources of Screening Levels Considered for Long-Term Exposure Analysis

Sources Considered

Potential Contaminants

Dioxin/Furans (µg/m3)3,4 Mercury (µg/m3)4

ATSDR MRL — 2.0E-01

40 CFR 61.52(a) 1 — 2.3E09

40 CFR 61.52(b) 2 — 3.2E09

USEPA ADI 2.2E-06 —

WHO Ambient Air 1.0E-07 5.0E-03 — 1.0E-02

WHO Time-Weighted Average — 1.0

OEHHA Chronic REL 4.0E-05 3.0E-02

USEPA RSL mercury salts — 3.1E-02

USEPA RSL 6.4E-08 3.1E-01

Notes: 1 Mercury ore facilities may not exceed 2300 grams mercury emissions per 24-hour period 2 Sludge incineration and drying facilities may not exceed 3200 grams mercury emissions per 24-hour period 3 µg/m3 — micrograms per cubic meter 4 Scientific notation (e.g., 2.2E-06) is used extensively in this report.



17

4.1.2 Discussion and Selection of Long-term Screening Levels

USEPA developed RSLs to determine if further evaluation or some other action is warranted based

on reported or modeled concentrations of pollutants. The USEPA User’s Guide for RSLs indicates

that these screening levels should not be used as cleanup “standards” until other options have been

evaluated and considered. RSLs are not regulations. RSLs are guidelines based on USEPA toxicity

values and exposure models that reflect a residential scenario. USEPA calculated the screening

levels using the methods outlined in their Risk Assessment Guidance for Superfund (RAGS) and

Soil Screening Guidance documents, which indicate that long-term exposure occurs for a duration

of seven years or more, and that screening levels based on residential land use represent exposure

over a lifetime (Risk Assessment Guidance for Superfund. Volume I: Human Health Evaluation

Manual (Part A). Interim Final, Office of Emergency and Remedial Response,

USEPA/540/1-89/002USEPA). USEPA’s RSL’s are screening levels that consider the inhalation of

contaminants through air in a residential setting, assuming exposure over a lifetime.

USEPA’s screening levels for ambient air based on a residential scenario would, therefore, be

a conservative selection, would be protective of the public, and are well-known and established

risk-based screening tools. Consequently, USEPA’s RSLs for residential air were selected as

the primary screening levels for comparison to the maximum annual average air concentrations

that were predicted using AERMOD. As previously discussed, the screening level for dioxins was

used as the screening level for furans. Additionally, the screening level for elemental mercury was

used for comparison with the predicted ambient air concentrations of mercury, as opposed to

screening levels for mercury salts or organic mercury compounds, because the emission factors

used to estimate emissions from the crematory are for mercury vapor and this is most likely

the form in which almost all the mercury is emitted.

4.1.3 Discussion and Selection of Short-term Screening Levels

As indicated above, USEPA RSLs were used, assuming long-term exposure occurs over a lifetime.

However, short-term, or acute exposure, could also occur in the vicinity of the proposed

crematorium, so the scientific and regulatory literature was also searched for short-term screening

levels. No short-term screening level is available from USEPA for dioxin, furan, or mercury;

however, 1-hour and 8-hour RELs are available from the California OEHHA for mercury. The 1-hour

REL available from OEHHA is 0.6 µg/m3, and the 8-hour REL is 0.06 µg/m3.

Although the California OEHHA RELs were identified in the literature, there are some uncertainties

associated with using them in this analysis, including the following:



18

The predicted ambient air concentrations were for elemental mercury vapor only, but

the REL is based on a group of compounds including mercury salts. This could result in

an overstatement of the risk considering that mercury salts are generally considered

more toxic than elemental mercury.

Short-term health effects are possible if sufficient exposure occurs, but short-term toxicity

thresholds have not been well documented by the scientific community.

Mercury accumulates in the body, so short-term repeated exposures could result in

toxic effects that are unanticipated by the OEHHA short-term REL which could result in

an understatement of risks.

OEHHA RELs are based on various health effects compiled in December 2008, which could

under- or over-state exposure and risk for children or other sensitive populations.

No other short-term screening levels were identified in the literature; therefore the OEHHA RELs

were used as screening levels, notwithstanding the uncertainties outlined above in order to provide

some context for the short-term ambient air concentrations of mercury predicted by

the AERMOD modeling.

4.2 Comparison of Predicted Ambient Air Concentrations with Selected Screening

Levels

Table 4 provides a detailed comparison of both the long-term and short-term predicted ambient air

concentrations of mercury and the long-term ambient air concentrations of dioxins and furans with

the corresponding screening levels.



Notes: * Screening Levels were obtained from USEPA and OEHHA as described in Section 4.1.2. No screening level was identified for furans. The dioxin screening level is used as a surrogate for the furans.

19

Table 4 Modeling Results and Comparisons to Risk-Based Screening Levels

Chemical/Emission Rate Time Frame Emission Rate

(g/s)

Max Unit Predicted Concentration (µg/m3/g/s)

Max Predicted Concentration

(µg/m3)

Screening Level

(µg/m3)*

Percent of

Screening Level (%) Above?

Entire Modeling Domain

Mercury — USEPA Emission Rate 1-hr/ Acute

4.15E-04 n/a 0.14 0.6 23 NO

Mercury — Max Emission Rate 2.39E-03 n/a 0.80 0.6 133 YES

Mercury — USEPA Emission Rate 8-hr/Acute

1.55E-04 n/a 0.038 0.06 63 NO


Mercury - USEPA Emission Rate Annual/Chronic

1.38E-04 n/a 0.005 0.03 17 NO

Mercury — Max Emission Rate 7.96E-04 n/a 0.026 0.03 87 NO

Dioxins — Total Annual/Chronic 9.87E-10 32.9 3.25E-08 6.40E-08 51 NO

Furans — Total Annual/Chronic 1.48E-09 32.9 4.88E-08 6.40E-08 76 NO

Special Receptor — Nearby Neighborhood to the North


4.15E-04 n/a 0.14 0.6 23 NO



1.55E-04 n/a 0.029 0.06 48 NO


Mercury — USEPA Emission Rate Annual/Chronic

1.38E-04 n/a 0.0031 0.03 10 NO







20



(g/s)



(µg/m3)

Screening Level

(µg/m3)*

Percent of


Special Receptor — Harvey Park — 4001 Miles Johnson Parkway


4.15E-04 n/a 0.037 0.6 6 NO



1.55E-04 n/a 0.0051 0.06 9 NO



1.38E-04 n/a 0.00017 0.03 1 NO




Special Receptor — Evens Park — 575 Maury Hill Street

Mercury - USEPA Emission Rate 1-hr/ Acute

4.15E-04 n/a 0.013 0.6 2 NO

Mercury - Max Emission Rate 2.39E-03 n/a 0.072 0.6 12 NO

Mercury - USEPA Emission Rate 8-hr/Acute

1.55E-04 n/a 0.0019 0.06 3 NO


Mercury - USEPA Emission Rate Annual/Chronic

1.38E-04 n/a 0.00005 0.03 0 NO


Dioxins – Total Annual/Chronic 9.87E-10 0.33 3.26E-10 6.40E-08 1 NO

Furans – Total Annual/Chronic 1.48E-09 0.33 4.89E-10 6.40E-08 1 NO




21



(g/s)



(µg/m3)

Screening Level

(µg/m3)*

Percent of


Special Receptor — First Baptist — 5219 Main Street


4.15E-04 n/a 0.11 0.6 18 NO



1.55E-04 n/a 0.022 0.06 37 NO



1.38E-04 n/a 0.00092 0.03 3 NO




Special Receptor — Spring Hill Presbyterian — 5344 Main Street


4.15E-04 n/a 0.012 0.6 2 NO



1.55E-04 n/a 0.0022 0.06 4 NO



1.38E-04 n/a 0.00008 0.03 0 NO







22



(g/s)



(µg/m3)

Screening Level

(µg/m3)*

Percent of


Special Receptor — Elementary School — 5359 Main Street


4.15E-04 n/a 0.012 0.6 2 NO



1.55E-04 n/a 0.0023 0.06 4 NO



1.38E-04 n/a 0.00006 0.03 0 NO




Special Receptor — Children’s Home — 804 Branham Hughes Circle


4.15E-04 n/a 0.034 0.6 6 NO



1.55E-04 n/a 0.0039 0.06 7 NO



1.38E-04 n/a 0.00015 0.03 1 NO






23

5.0 DISCUSSION OF RESULTS

Based on the results of the dispersion modeling analysis of emissions from the proposed

crematorium performed using emissions estimated from USEPA emission factors, no predicted

long-term ambient air concentrations of mercury, total dioxins, or total furans exceeded the selected

EPA long-term screening levels at any location in the vicinity of the proposed crematorium.

Based on the results of the dispersion modeling analysis of emissions from the proposed

crematorium performed using emissions estimated from the highest mercury body content found in

the published literature (8.6 g/body), the maximum 1-hour and 8-hour ambient air concentrations

of mercury exceeded the short-term California OEHHA screening levels at some locations in

the vicinity of the proposed crematory.

It should be noted, in the case of the maximum 1-hr emissions, that in the dispersion modeling

analysis it was assumed that all the mercury in the cremated body was emitted in one hour.

That 1-hour emission rate was then assumed to occur every hour of the 5 years that was modeled

(See Section 3.1.3 for a discussion of the meteorological data used in the analysis.) This is

the most conservative assumption that could be made. This approach ensured that the highest

mercury emission rate coincided with the one hour during those 5 years when the meteorological

conditions would result in the maximum concentration in each receptor grid in the modeling

domain, including the special receptors modeled at the request of the BOMA.

In the case of the maximum 8-hr emissions, in the dispersion modeling analysis it was assumed

that there would be three consecutive cremations occurring (that is, there would three consecutive

cremation cycles of three hours each – half hour for warm-up, two hours for the cremation and half

hour cool-down) and that all the mercury was emitted in the first hour of each cremation. Thus it

was assumed that there would be three maximum 1-hr emissions every 8 hours. This, too, is the

most conservative assumption that could be made. This approach, like that of the 1-hr approach

discussed above, ensured that the maximum mercury emission rate modeled coincided with the

eight hour period when the meteorological conditions resulted in the maximum concentration in

each receptor grid in the modeling domain.

These very conservative assumptions were made to address the uncertainty related to both the

emission rates and screening levels selected for the analysis. Given that (1) the number of

cremations per year is expected to be much lower than assumed in the analysis, (2) the short-term

screening levels selected were conservative (see Section 4.1.3), and (3) the short-term screening

level exceedances resulted from an emission rate based on the highest mercury body content found

in the literature at the time when the meteorological conditions resulted in the highest

concentrations in each receptor grid, it is unlikely that the predicted emissions would result in

adverse health effects.



24

6.0 CONCLUSIONS

Based on the results of dispersion modeling of emissions from the crematory performed using

emissions estimated from USEPA emission factors, no predicted short-term or long-term ambient air

concentrations of mercury or long-term ambient air concentrations of total dioxins or total furans

exceeded the selected screening levels at any location in the vicinity of the proposed crematorium.

This indicates that the risk of adverse public health impacts resulting from emissions of these

pollutants is low.



25

7.0 REFERENCES

Agency for Toxic Substances and Disease Registry. Minimal Risk Levels. Downloaded

October 2011 from : http://www.atsdr.cdc.gov/mrls/index.asp.

California Office of Environmental Health Hazard Assessment Toxic Air Contaminant Program.

September 2008 Mercury Reference Exposure Level Technical Support Document.

Downloaded October 2011 from:

http://oehha.ca.gov/air/hot_spots/2008/AppendixD1_final.pdf#page=214.

California Office of Environmental Health Hazard Assessment Toxic Air Contaminant Program.

September 2000 Chlorinated Dibenzo-p-Dioxins and Chlorinated Dibenzofurans. Reference

Exposure Level Technical Support Document. Downloaded October 2011 from:

http://www.oehha.ca.gov/air/hot_spots/2008/AppendixD3_final.pdf#page=90.

U.S. USEPA 1989. Risk assessment guidance for Superfund. Volume I: Human health evaluation

manual (Part A). Interim Final. Office of Emergency and Remedial Response.

USEPA/540/1-89/002.

U.S. USEPA 1991a. Human health evaluation manual, supplemental guidance: "Standard default

exposure factors". OSWER Directive 9285.6-03.

U.S. USEPA 1991b. Risk Assessment Guidance for Superfund, Volume I: Human Health Evaluation

Manual (Part B, Development of Risk-Based Preliminary Remediation Goals). Office of

Emergency and Remedial Response. USEPA/540/R-92/003. December 1991.

U.S. USEPA. 1994. USEPA Dioxin Reassessment. Vol. 1, p. 37 (Figure II-5).

U.S. USEPA. 1997a. Exposure Factors Handbook. Office of Research and Development, Washington,

DC. USEPA/600/P-95/002Fa.

U.S. USEPA 2000. Exposure and Human Health Reassessment of 2,3,7,8-Tetrachlorodibenzo-p-Dioxin

(TCDD) and Related Compounds. Part I: Estimating Exposure to Dioxin-Like Compounds.

Volume 3--Properties, Environmental Levels, and Background Exposures. Draft Final Report.

USEPA/600/P- 00/001. Office of Research and Development, Washington, DC. September.

http://epa-prgs.ornl.gov/chemicals/help/documents/EFH_Final_1997_EPA600P95002Fa.pdf



26

U.S. USEPA, 2001. WATER9. Version 1.0.0. Office of Air Quality Planning and Standards, Research

Triangle Park, NC. Web site at http://www.USEPA.gov/ttn/chief/software/water/index.html.

U.S. USEPA 2002. Supplemental Guidance for Developing Soil Screening Levels for Superfund Sites.

OSWER 9355.4-24. December 2002.

http://www.USEPA.gov/superfund/health/conmedia/soil/index.htm.

U.S. USEPA 2009. Risk Assessment Guidance for Superfund Volume I: Human Health Evaluation

Manual (Part F, Supplemental Guidance for Inhalation Risk Assessment) Final. OSWER

9285.7-82. January 2009. Document, memo and website

http://www.USEPA.gov/oswer/riskassessment/ragsf/index.htm.

U.S. USEPA 2011. Regional Screening Levels and User’s Guide. May 2011. website

http://www.USEPA.gov/reg3hwmd/risk/human/rb-concentration_table/usersguide.htm.

U.S. Food and Drug Administration. Cumulative Estimated Daily Intake. Website

http://www.accessdata.fda.gov/scripts/sda/sdNavigation.cfm?sd=edisrev.

World Health Organization 2000. Air Quality Guidelines. Downloaded October 2011 from:

http://www.euro.who.int/__data/assets/pdf_file/0005/74732/E71922.pdf.

J:\Nashville\A-L\Henry Henry Underwood\Spring Hill Modeling Report 1108 FINAL DRAFT.docx

http://epa-prgs.ornl.gov/chemicals/help/documents/iwairuxb.pdf

http://www.epa.gov/ttn/chief/software/water/index.html

Appendix A

Emission Rate Calculations

MERCURY

CHRONIC EXPOSURE

USEPA Emission Rate

Based on USEPA FIRE Database emission factor of 3.29E-03 lbs mercury per body and 3 hours

per cremation

((3.29E-03 lbs/body) X (453.59 g/lb) / (3 hrs/body))/ (3600 sec/hr) = 1.38E-04 g/sec

Maximum Mercury Emission Rate

Based on high end of range of mercury per body (8.6 g/body) as reported in unpublished

draft report Summary of References on Mercury Emissions from Crematoria, John Riendl,

November 3, 2008, and 3 hours per cremation

(8.6 g/body) / (3 hrs/body) / (3600 sec/hr) = 7.96E-04 g/sec

ACUTE EXPOSURE

1-Hour Maximum Emission Rate

USEPA Emission Rate

Based on USEPA FIRE Database emission factor of 3.29E-03 lbs mercury per body and all mercury

emitted in one hour

((3.29E-03 lbs/body) X (453.59 g/lb) / (1 hr/body))/ (3600 sec/hr) = 4.15E-04 g/sec



draft report Summary of References on Mercury Emissions from Crematoria, John Riendl,

November 3, 2008, and all mercury emitted in one hour

(8.6 g/body) / (1 hr/body) / (3600 sec/hr) = 2.39E-03 g/sec

8-Hr Average Emission Rate

USEPA Emission Rate

Based on USEPA FIRE Database emission factor of 3.29E-03 lbs mercury per body and a maximum

of three 1-hour emissions per 8-hour period

(4.15E-04 g/sec) X 3/8 = 1.55E-04 g/sec



draft report Summary of References on Mercury Emissions from Crematoria, November 3, 2008,

and a maximum of three 1-hour emissions per 8-hour period

(2.39E-03 g/sec) X 3/8 = 8.96E-04 g/sec

TOTAL PCDD (DIOXINS)

CHRONIC EXPOSURE

Based on USEPA FIRE Database emission rate of 2.35E-08 lbs/body burned and an average

cremation time of 3 hours per cremation

(2.35E-08 lbs/body) X (453.59 g/lb) / (3hrs/body) / (3600 sec/hr) = 9.87E-10 g/sec

TOTAL PCDF (FURANS)

CHRONIC EXPOSURE

Based on USEPA FIRE Database emission rate of 3.53E-08 lbs/body burned and an average

cremation time of 3 hours per cremation

(3.53E-08 lbs/body) X (453.59 g/lb) / (3hrs/body) / (3600 sec/hr) = 1.48 E-09 g/sec

Appendix B Modeling Files and Descriptions

Modeling Files and Descriptions

File Description

AERMET files.zip

13897-01.ISH Raw Nashville, TN surface met data file, 2001





BNA2001.fsl Raw Nashville, TN upper air met data file, 2001





BNA01_S1 [.INP, .RPT, .SUM] AERMET Stage 1 [input, report, summary] file, 2001















AERSURFACE files.zip

BNA land use.zip Land use data for Nashville, TN Airport

BNA_1km.log AERSURFACE log file

BNA_1km.out AERSURFACE output file

Met data files.zip

BNABNA5Y.sfc AERMOD surface met data file, combined five year file: 2001 — 2005

BNABNA5Y.pfl AERMOD profile met data file, combined five year file: 2001 — 2005

BPIP-PRIME Files.zip

Spring_Hill.pip BPIP-PRIME input file

Spring_Hill.so BPIP-PRIME output file

Spring_Hill.sum BPIP-PRIME output file

Spring_Hill.tab BPIP-PRIME output file

AERMAP Files.zip

Spring_Hill.map AERMAP input file

Spring_Hill.mot AERMAP output file

Spring_Hill.rcf AERMAP receptor output file

Spring_Hill.srf AERMAP sources, buildings output file

AERMOD Files.zip

Spring_Hill_HG-01.dta AERMOD input file: Mercury — USEPA emission rate, 1-hour/Acute

Spring_Hill_HGm-01.dta AERMOD input file: Mercury — Max emission rate, 1-hour/Acute

Spring_Hill_HG-08.dta AERMOD input file: Mercury — USEPA emission rate, 8-hour/Acute

Spring_Hill_HGm-08.dta AERMOD input file: Mercury — Max emission rate, 8-hour/Acute

Spring_Hill_HG-AN.dta AERMOD input file: Mercury — USEPA emission rate, Annual/Chronic

Spring_Hill_HGm-AN.dta AERMOD input file: Mercury — Max emission rate, Annual/Chronic

Spring_Hill_D-F.dta AERMOD input file: Dioxins/Furans, unit emission rate, Annual/Chronic

Spring_Hill_HG-01.grf AERMOD plot file: Mercury — USEPA emission rate, 1-hour/Acute

Spring_Hill_HGm-01.grf AERMOD plot file: Mercury — Max emission rate, 1-hour/Acute

File Description

Spring_Hill_HG-08.grf AERMOD plot file: Mercury — USEPA emission rate, 8-hour/Acute

Spring_Hill_HGm-08.grf AERMOD plot file: Mercury — Max emission rate, 8-hour/Acute

Spring_Hill_HG-AN.grf AERMOD plot file: Mercury — USEPA emission rate, Annual/Chronic

Spring_Hill_HGm-AN.grf AERMOD plot file: Mercury — Max emission rate, Annual/Chronic

Spring_Hill_D-F.grf AERMOD plot file: Dioxins/Furans, unit emission rate, Annual/Chronic

Spring_Hill_HG-01.out AERMOD output file: Mercury — USEPA emission rate, 1-hour/Acute

Spring_Hill_HGm-01.out AERMOD output file: Mercury — Max emission rate, 1-hour/Acute

Spring_Hill_HG-08.out AERMOD output file: Mercury — USEPA emission rate, 8-hour/Acute

Spring_Hill_HGm-08.out AERMOD output file: Mercury — Max emission rate, 8-hour/Acute

Spring_Hill_HG-AN.out AERMOD output file: Mercury — USEPA emission rate, Annual/Chronic

Spring_Hill_HGm-AN.out AERMOD output file: Mercury — Max emission rate, Annual/Chronic

Spring_Hill_D-F.out AERMOD output file: Dioxins/Furans, unit emission rate, Annual/Chronic

Documents

Mercury Spring Hill Modeling Report