2014

7/24/2014

EJ Screening Report for Primary Aluminum
Contents	

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

About the Data........................................................................................................................................................................6

    Demographic Data...............................................................................................................................................................7

Statistical Summary.................................................................................................................................................................8

    Category Totals, Wilcoxon Signed-Rank and Binomial Tests................................................................................................9

Near Source Data ..................................................................................................................................................................15

Map and Charts.....................................................................................................................................................................17

Meaningful Involvement Summary.......................................................................................................................................23

Risk and Technology Review ‐ Analysis of Socio‐Economic Factors for Populations Living Near Primary Aluminum Facilities

...............................................................................................................................................................................................27

   

2
U.S. Environmental Protection Agency 

Environmental Justice Screening Report 

National Emissions Standards for 

Hazardous Air Pollutants From 

Primary Aluminum 

Docket: EPA‐HQ‐OAR‐2011‐0797

Office of Air and Radiation, 

Office of Air Quality Planning and Standards 

Research Triangle Park, NC 27711 

3
Executive Summary

The EPA is finalizing amendments to national emission standards for hazardous air pollutants (NESHAP) for primary

aluminum production. Under section 112 of the Clean Air Act, “the Administrator shall review, and revise as necessary

(taking into account developments in practices, processes, and control technologies), emission standards promulgated

under this section no less often than every 8 years.”  

To gain a better understanding of the primary aluminum source category and near‐source populations, the EPA

conducted a proximity analysis at a study area of 3 miles of the source category for this rulemaking. This analysis

identifies, on a limited basis, the subpopulations that may be exposed to air pollution from the regulated sources and

thus are expected to benefit most from this regulation. This analysis does not identify the demographic characteristics of

the most highly affected individuals or communities, nor does it quantify the level of risk faced by those individuals or

communities. To the extent that any minority, low‐income or indigenous subpopulation is disproportionately impacted

by hazardous air emissions due to the proximity of their homes to sources of these emissions, that subpopulation also

stands to see increased environmental and health benefit from the emission reductions called for by this rule.  

EPA has determined that this final rule will not have disproportionately high and adverse human health or

environmental effects on minority or low‐income populations because it increases the level of environmental protection

for all affected populations without having any disproportionately high and adverse human health or environmental

effects on any population, including any minority or low‐income population.

Background

Executive Order (EO) 12898 (59 FR 7629 (Feb. 16, 1994)) establishes federal executive policy on environmental justice.  

Its main provision directs federal agencies, to the greatest extent practicable and permitted by law, to make

environmental justice part of their mission by identifying and addressing, as appropriate, disproportionately high and

adverse human health or environmental effects of their programs, policies, and activities on minority populations and

low‐income populations in the United States.  E.O. 12898 informed the development and implementation of the EPA’s

Environmental Justice (EJ) program and EJ policies. Consistent with the E.O. and the Presidential Memorandum that

accompanies the E.O., the agency’s EJ policies promote environmental protection by focusing attention and agency

efforts on addressing the types of environmental harms and risks that are prevalent among minority, low‐income and

indigenous populations. E.O. 12898 and the agency’s EJ policies do not mandate particular outcomes for an action, but

they demand that decisions involving the action be informed by a consideration of EJ issues. Where feasible, actions

should prevent or address and mitigate EJ concerns.

A key element of environmental justice is ensuring that all people have an opportunity for meaningful involvement in

the decision‐making process. Certain groups may not have participated in the decision‐making process historically

because of economic (e.g., income), social (e.g., language barriers, education levels, distrust of government) and

structural reasons. A critical concern is whether, and the extent to which, communities have the ability to influence the

types and number of regulated activities taking place in their community, as well as the requirements, conditions and

parameters by which such regulated activities must operate (e.g., permit conditions).

The EPA aims to notify and engage the public in a variety of ways. Each rule is reviewed to identify appropriate

mechanisms to promote meaningful involvement, which may include notices on the EJAir website, community call

discussions, fact sheets, community meetings and/or webinars. Additionally, when reliable source location data is

available, the EPA strives to provide a screening report of near source populations. It is important to note that while the

EPA provides near‐source data, whether or not a facility‐level analysis is appropriate depends on the Clean Air Act’s

4
(CAA) authority for the subject rule. For example, CAA sections 112 (d) and 112(f), which address hazardous air

pollutants, require the EPA to establish emission standards that apply to all sources in specified categories or

subcategories. In the case of the CAA 112(f), the EPA sets standards based on the maximum exposed individual risk

(MIR) or the facility in the source category that poses the highest risks to the public, and must consider specific statutory

factors, including costs, energy and safety.

5
About the Data

6
Demographic Indicators		

Percent Minority

% minority as fraction of population, where minority is defined as all but Non‐Hispanic White Alone (Source: Census

ACS

2006‐2010).

Percent Low Income

% low income (under 2 times the poverty threshold) as fraction of individualsfor whom ratio was determined

(Source: Census ACS 2006‐2010).

Percent Less than High School

% with less than high school degree (as fraction of those age 25+) (Source: Census ACS 2006‐2010).

Percent Linguistic Isolation

% linguistically isolated (as fraction of households) (Source: Census ACS 2006‐2010).

Percent Under Age 5

% under age 5 as fraction of population (Source: Census ACS 2006‐2010).

Percent Over Age 64

% over age 64 as fraction of population (Source: Census ACS 2006‐2010).

7
Statistical Summary

8
Category Totals, Wilcoxon Signed-Rank and Binomial Tests 

The EPA compares aggregated study area demographics to U.S. demographics in three tables within this section: 

 Table 1 – Demographic totals for the entire source category and U.S. demographic totals

 Table 2 – Median demographics across study areas vs. U.S. average demographics

 Table 3 – Proportion of study areas with populations exceeding U.S. average demographics

Table 1 is simply calculated by summing the demographic data in the study areas; however, urban study areas can often skew 

the data. Therefore, Tables 2 and 3 use statistical inference to answer two additional and specific questions: 

1. On average, how much do the demographics within the study areas differ from the U.S. population?

2. How often do the demographic proportions within the study areas exceed the U.S. average?

Table 2 – Hypothesis Test for Question 1 (Wilcoxon Signed-Rank test for population median)1

 Null Hypothesis (H0): The proportion of the population in demographic category X within a given study area is a

random variable with median EQUAL TO the U.S. average.

 Alternative Hypothesis (H1): The proportion of the population in demographic category X within a given study area is a

random variable with median NOT EQUAL TO the U.S. average.

 Test Statistic: The Wilcoxon Signed-Rank statistic (W) is the sum of the signed ranks of the study areas where the

study area demographics exceed the U.S. average. If there are N study areas, W has range 0 to N*(N+1)/2. The pvalue is the probability that H0 is true given the value of W calculated from the demographic data.

 Statistical Conclusions:

o If the p-value is large (≥ 0.05): The median proportion of the study area population in demographic category

X is not significantly different from the U.S. average.

o If the p-value is small (< 0.05) and W > N*(N+1)/4: The median proportion of the study area population in

demographic category X is significantly greater than the U.S. average.

o If the p-value is small (< 0.05) and W < N*(N+1)/4: The median proportion of the study area population in

demographic category X is significantly less than the U.S. average.

 Study areas with fewer than 100 total residents are ignored.

Table 3 – Hypothesis Test for Question 2 (Binomial test for occurrence)1 

 Null Hypothesis (H0): The probability of a given study area having population in demographic category X greater than

the U.S. average is EQUAL TO 50%.

 Alternative Hypothesis (H1): The probability of a given study area having population in demographic category X

greater than the U.S. average is NOT EQUAL TO 50%.

 Test statistic: B = # of study areas with population greater than the U.S. average

 If H0 is true and there are N study areas, then B/N has a Binomial distribution with mean = 50%. The p-value is the

probability that H0 is true given the value of B calculated from the demographic data.

 Statistical Conclusions:

o If the p-value is large (≥ 0.05): The probability of a given study area having population in demographic

category X exceeding the U.S. average is not significantly different from 50%.

o If the p-value is small (< 0.05) and B > N/2: The probability of a given study area having population in

demographic category X exceeding the U.S. average is significantly greater than 50%.

o If the p-value is small (< 0.05) and B < N/2: The probability of a given study area having population in

demographic category X exceeding the U.S. average is significantly less than 50%.

 Study areas with fewer than 100 total residents are ignored.

A qualitative summary on the statistical significance immediately follows the tabular data in this section. 

1

 Wilcoxon Signed-Rank and Binomial tests are designed for use when the number of study areas is small. Other tests may be used in place of these tests for Tables 2 

and 3 when there are more than 20 study areas. 

9
Statistical Data

Category Totals, Wilcoxon Signed-Rank and Binomial Tests

Table 1 - Category-wide Total

Population Minority

Linguistically 

Isolated Age 0 - 4 Age 65+

Without a HS 

Diploma Low Income

NEAR SOURCE TOTAL 68,201 17% 1% 7% 13% 13% 31%

NATIONAL TOTAL 307,727,594 36% 5% 7% 13% 15% 32%

Table 2 - Hypothesis Test 1 (Wilcoxon Signed-Rank Test for Median Near-Source Population)

H0: Median % of Population Near Sources in Category X = National % in Category X # of Study Areas >= 100 total population (N) 13

H1: Median % of Population Near Sources in Category X ≠ National % in Category X

Minority

Linguistically 

Isolated Age 0 - 4 Age 65+

Without a HS 

Diploma Low Income

9 1 41 57 41 48

0.0071 0.0004 0.7611 0.4346 0.7611 0.8660

Table 3 - Hypothesis Test 2 (Binomial Test for Occurrence)

H0: Prob. (Study area with Nearby Population in Category X is above National Average) = 50%

H1: Prob. (Study area with Nearby Population in Category X is above National Average) ≠ 50%

Minority

Linguistically 

Isolated Age 0 - 4 Age 65+

Without a HS 

Diploma Low Income

2 1 8 7 5 7

0.0129 0.0018 0.4240 0.7905 0.4240 0.7905

STATISTICAL SIGNIFICANCE LEVEL

No Significance (P >= 0.05)

Significant (P < 0.05 and W > N*(N+1)/4 or B > N/2)

Significantly Less (P < 0.05 and W < N*(N+1)/4 or B < N/2)

STATISTIC

# STUDY AREAS > NATIONAL AVG (B)

P-VALUE

STATISTIC

WILCOXON STATISTIC (W)

P-VALUE

Demographic Summary

10
Statistical Summary (Category Totals, Wilcoxon Signed-Rank and Binomial Tests)

Demographic Category Minority

Summary of the data:

Demographic Category Linguistically Isolated

Summary of the data:

Table 3 indicates that 1 study areas have a greater Linguistically Isolated population than the national average. 

This is significantly less from the 50% we would expect if the study areas were randomly distributed across the 

U.S.

The national proportion (Table 1) and median proportion (Table 2) of Linguistically Isolated populations living in 

the study areas are both less than the national average. Furthermore, 1 study areas have Linguistically Isolated 

populations greater than the national average (Table 3). This suggests that the proportion of Linguistically 

Isolated populations living in the study areas is significantly less than the national average.

Table 1 indicates that nationally, 17% of the people living within 3.0 miles of the study areas are Minority. This is 

-19 point(s), or -52.8%, compared to the national average of 36% in 2010.

Table 2 indicates that the Wilcoxon Signed-Rank statistic for Minority populations is 9. The value of 9 is 

significantly less when compared to the national average.

Table 3 indicates that 2 study areas have a greater Minority population than the national average. This is 

significantly less from the 50% we would expect if the study areas were randomly distributed across the U.S.

The national proportion (Table 1) and median proportion (Table 2) of Minority populations living in the study 

areas are both less than the national average. Furthermore, 2 study areas have Minority populations greater 

than the national average (Table 3). This suggests that the proportion of Minority populations living in the study 

areas is significantly less than the national average.

Table 1 indicates that nationally, 1% of the people living within 3.0 miles of the study areas are Linguistically 

Isolated. This is -4 point(s), or -80%, compared to the national average of 5% in 2010.

Table 2 indicates that the Wilcoxon Signed-Rank statistic for Linguistically Isolated populations is 1. The value of 

1 is significantly less when compared to the national average.

11
Statistical Summary (Category Totals, Wilcoxon Signed-Rank and Binomial Tests)

Demographic Category Age 0 - 4

Summary of the data:

Demographic Category Age 65+

Summary of the data:

Table 2 indicates that the Wilcoxon Signed-Rank statistic for Age 65+ populations is 57. The value of 57 is not 

significant when compared to the national average.

Table 3 indicates that 7 study areas have a greater Age 65+ population than the national average. This is not 

significant from the 50% we would expect if the study areas were randomly distributed across the U.S.

The national proportion (Table 1) and median proportion (Table 2) of Age 65+ populations living in the study 

areas are not significantly different than the national average. Furthermore, 7 study areas have Age 65+ 

populations greater than the national average (Table 3). This suggests that the median proportion of Age 65+ 

populations living in the study areas is not significantly different than the national average, and there is a large 

amount of variability among the study areas.

Table 1 indicates that nationally, 7% of the people living within 3.0 miles of the study areas are Age 0 - 4. This is 

approximately equal to the national average of 7% in 2010.

Table 2 indicates that the Wilcoxon Signed-Rank statistic for Age 0 - 4 populations is 41. The value of 41 is not 

significant when compared to the national average.

Table 3 indicates that 8 study areas have a greater Age 0 - 4 population than the national average. This is not 

significant from the 50% we would expect if the study areas were randomly distributed across the U.S.

The national proportion (Table 1) and median proportion (Table 2) of Age 0 - 4 populations living in the study 

areas are not significantly different than the national average. Furthermore, 8 study areas have Age 0 - 4 

populations greater than the national average (Table 3). This suggests that the median proportion of Age 0 - 4 

populations living in the study areas is not significantly different than the national average, and there is a large 

amount of variability among the study areas.

Table 1 indicates that nationally, 13% of the people living within 3.0 miles of the study areas are Age 65+. This is 

approximately equal to the national average of 13% in 2010.

12
Statistical Summary (Category Totals, Wilcoxon Signed-Rank and Binomial Tests)

Demographic Category Without a HS Diploma

Summary of the data:

Demographic Category Low Income

Summary of the data:

The national proportion (Table 1) of Low Income populations living in the study areas is less than the national 

average; however, the median proportion (Table 2) is not significantly different than the national average. 

Furthermore, 7 study areas have Low Income populations greater than the national average (Table 3). This 

suggests that the median proportion of Low Income populations living in the study areas is not significantly 

different than the national average, and there is a large amount of variability among the study areas.

Table 3 indicates that 5 study areas have a greater Without a HS Diploma population than the national average. 

This is not significant from the 50% we would expect if the study areas were randomly distributed across the 

U.S.

The national proportion (Table 1) of Without a HS Diploma populations living in the study areas is less than the 

national average; however, the median proportion (Table 2) is not significantly different than the national 

average. Furthermore, 5 study areas have Without a HS Diploma populations greater than the national average 

(Table 3). This suggests that the median proportion of Without a HS Diploma populations living in the study 

areas is not significantly different than the national average, and there is a large amount of variability among the 

study areas.

Table 1 indicates that nationally, 31% of the people living within 3.0 miles of the study areas are Low Income. 

This is -1 point(s), or -3.1%, compared to the national average of 32% in 2010.

Table 2 indicates that the Wilcoxon Signed-Rank statistic for Low Income populations is 48. The value of 48 is 

not significant when compared to the national average.

Table 3 indicates that 7 study areas have a greater Low Income population than the national average. This is not 

significant from the 50% we would expect if the study areas were randomly distributed across the U.S.

Table 1 indicates that nationally, 13% of the people living within 3.0 miles of the study areas are Without a HS 

Diploma. This is -2 point(s), or -13.3%, compared to the national average of 15% in 2010.

Table 2 indicates that the Wilcoxon Signed-Rank statistic for Without a HS Diploma populations is 41. The value 

of 41 is not significant when compared to the national average.

13
Aggregated Data Statisical Summary

Hypothesis 1 Hypothesis 2

Median Near-Source Population

Wilcoxon Signed-Rank Test

(Table 2)

Occurrence

Binomial Test

(Table 3)

Population 307,727,594 68,201

Minority 36% 17% -53% Significantly Less Significantly Less

Linguistically Isolated 5% 1% -80% Significantly Less Significantly Less

Age 0 - 4 7% 7% 0% Not Significant Not Significant

Age 65+ 13% 13% 0% Not Significant Not Significant

Without a HS Diploma 15% 13% -13% Not Significant Not Significant

Low Income 32% 31% -3% Not Significant Not Significant

Demographic National Near Source

(Table 1)

% Difference

Near vs. National

14
Near Source Data

15
Raw Data

Region State Name ID Population Minority Low Income Linguistically 

Isolated

Less than HS 

Education

Under Age 5 Over Age 64

2 NY ALCOA - MASSENA WEST 110000582735 12,425 6.7% 40.4% 0.8% 11.8% 7.0% 18.2%

ALCOA - MASSENA EAST 110000326111 1,154 64.1% 28.4% 4.5% 19.4% 5.2% 15.4%

3 WV CENTURY ALUMINUM OF 1,169

WEST VIRGINIA INC

110032631267 0.2% 34.2% 0.0% 17.3% 3.7% 20.0%

4 KY CENTURY ALUMINUM OF 8,894

KENTUCKY LLC

110000380917 1.7% 32.2% 0.0% 15.3% 5.1% 18.9%

Century Aluminum-Sebree 110038162118 888 11.0% 30.9% 0.8% 13.4% 7.7% 10.9%

SC ALUMAX OF SOUTH 26,857

CAROLINA

110002329454 29.3% 27.0% 0.7% 12.1% 7.4% 7.4%

5 IN ALCOA INC. - WARRICK 1,120

OPERATIONS

110000602045 3.6% 8.9% 0.0% 14.4% 7.0% 14.6%

OH ORMET PRIMARY 3,491

ALUMINUM CORP.

110000384888 1.6% 35.8% 0.0% 14.8% 5.4% 22.2%

6 LA ALCOA - LAKE CHARLES 3,690

CARBON COMPANY

110000449499 13.4% 19.1% 0.0% 13.4% 6.8% 8.9%

TX Alcoa Inc.--Rockdale 110008144025 58 17.5% 40.3% 0.3% 12.4% 8.1% 16.1%

7 MO NORANDA ALUMINUM INC 487

NEW MADRID

110017980639 9.3% 59.7% 0.0% 25.6% 9.4% 4.5%

8 MT COLUMBIA FALLS 4,024

ALUMINUM

110011868354 12.4% 37.3% 0.0% 9.2% 8.0% 11.5%

10 WA Alcoa Primary Metals Intalco 2,124

Works

110040947820 11.0% 21.4% 0.5% 7.4% 5.2% 16.5%

Aluminum Co of America 1,820

Wenatchee Works

110000491156 38.1% 49.3% 6.4% 27.6% 7.8% 12.0%

16
Map	and	Charts

17
18
Category Total % is calculated by summing all of the study area demographic data.

Category Average % is calculated by averaging the demographic data by the number of study areas where the total population >= 100.

36%

5%

7%

13%

15%

32%

17%

1%

7%

13% 13%

31%

16%

1%

7%

14%

15%

33%

0%

5%

10%

15%

20%

25%

30%

35%

40%

MINORITY LINGUISTICALLY ISOLATED AGE 0 - 4 AGE 65+ NO HIGH SCHOOL DIPLOMA LOW INCOME

Percentage Comparisons to National Averages

NATIONAL AVERAGE % CATEGORY TOTAL % CATEGORY AVERAGE %

19
The national average = 36%

Frequency

The national average = 5%

0-10% 10-20% 20-30% 30-40% 40-50% 50-60% More

Frequency 6 5 1 1 0 0 1

0

1

2

3

4

5

6

7

Frequency

Minority Demographic Histogram

0-2% 2-4% 4-6% 6-8% 8-10% 10-12% More

Frequency 12 0 1 1 0 0 0

0

2

4

6

8

10

12

14

Frequency

Linguistically Isolated Demographic Histogram

20
Frequency

The national average = 7%

The national average = 13%

0-2% 2-4% 4-6% 6-8% 8-10% 10-12% More

Frequency 0 1 4 6 3 0 0

0

1

2

3

4

5

6

7

Frequency

Age 0 - 4 Demographic Histogram

0-4% 4-8% 8-12% 12-16% 16-20% 20-24% More

Frequency 0 2 3 3 5 1 0

0

1

2

3

4

5

6

Frequency

Age 65+ Demographic Histogram

21
The national average = 15%

The national average = 32%

0-4% 4-8% 8-12% 12-16% 16-20% 20-24% More

Frequency 0 1 2 7 2 0 2

0

1

2

3

4

5

6

7

8

Frequency

No High School Diploma Demographic Histogram

0-10% 10-20% 20-30% 30-40% 40-50% 50-60% More

Frequency 1 1 3 5 3 1 0

0

1

2

3

4

5

6

Frequency

Low Income Demographic Histogram

22
Meaningful	Involvement	Summary

23
Meaningful Involvement

Outreach and Materials

 Updated and published rulemaking fact sheet.

o http://www.epa.gov/ttn/atw/alum/alumpg.html

 Broadcast rulemaking notices to various tribal contacts and the EJ listserv, in addition to listing on the publically

available websites Regulations.gov, Reginfo.gov and the Action Initiation List (AIL).

o EJ Listserv: https://lists.epa.gov/read/all_forums/subscribe?name=epa‐ej

 Will hold a 30 day public comment period on the rulemaking.

How to Comment

 EPA will accept comment on the proposal for 45 days after publication in the Federal Register. Comments,

identified by Docket ID No. EPA‐HQ‐OAR‐2011‐0797, may be submitted by one of the following methods:

o www.regulations.gov: Follow the on‐line instructions for submitting comments.

o E‐mail: Comments may be sent by electronic mail (e‐mail) to a‐and‐r‐Docket@epa.gov.

o Fax: Fax your comments to: 202‐566‐9744.

o Mail: Send your comments to:

U.S. Environmental Protection Agency  

EPA Docket Center

Mail Code: 28221T 1200 Pennsylvania Ave., NW  

Washington, DC, 20460

o Express Mail, Commercial Delivery, Hand Delivery or Courier: Such deliveries are only accepted during

the Docket’s normal hours of operation, and special arrangements should be made for deliveries of

boxed information. Deliver your comments to:  

EPA Docket Center

WJC West Building, Room 3334

1301 Constitution Ave., NW

Additional Information

 The Basics of the Regulatory Process

o http://www2.epa.gov/laws‐regulations/basics‐regulatory‐process

 Search for Regulations

o http://www.regulations.gov

 Get Involved with EPA Regulations

o http://www2.epa.gov/laws‐regulations/get‐involved‐epa‐regulations

 Frequent Questions about Dockets

o http://www.epa.gov/docket11/faqs.htm

 Follow the Action Initiation List (AIL)

o http://www2.epa.gov/laws‐regulations/actions‐initiated‐month#notification

24
 Where You Live

o http://www.epa.gov/epahome/whereyoulive.htm

 Air Pollution Training

o http://www.apti‐learn.net

 Air Quality Planning and Standards

o http://www.epa.gov/airquality/

 National Ambient Air Quality Standards

o http://www.epa.gov/air/criteria.html

o http://www.epa.gov/ttn/naaqs/

 Community Air Screening How‐To Manual

o http://www.epa.gov/oppt/cahp/pubs/howto.htm

 Risk Assessment and Modeling – Air Toxics Risk Assessment Reference Library

o http://www2.epa.gov/fera/risk‐assessment‐and‐modeling‐air‐toxics‐risk‐assessment‐reference‐library

 Technology Transfer Network

o Rules and Implementation: http://www.epa.gov/ttn/atw/eparules.html

o Evaluating Exposures to Toxic Air Pollutants – A Citizen's Guide:

http://www.epa.gov/ttn/atw/3_90_023.html

o Risk Assessment for Toxics – A Citizen’s Guide: http://www.epa.gov/ttn/atw/3_90_024.html

o Taking Toxics out of the Air: http://www.epa.gov/airquality/takingtoxics/

o Air Pollution and Health Risk: http://www.epa.gov/ttn/atw/3_90_022.html

Health Effects Notebook for HAPs: http://www.epa.gov/ttn/atw/hlthef/hapindex.html

25