OVERVIEW

Polygons in the Environmental Justice (EJ) Populations layer represent neighborhoods across the state with high minority, non-English speaking, low-income, and foreign-born populations. Data in this layer were derived from Summary File 3 at the blockgroup level (Summary Level 150) from 2000 U.S. Census data). Such areas are the focus of EOEA's EJ Policy, which was developed to use state resources to ensure that EJ populations receive a strong voice in environmental decision-making. For more information please visit EOEA's Environmental Justice Web page, which includes a detailed fact sheet as well as text of the full policy.

The layer is named EJ_POLY.

To view EJ maps in .PDF format or to access our Online EJ Viewer, see the EJ Maps page.

The layer was produced by identifying polygons from the Census 2000 Block Groups layer which met the following four criteria (items in parentheses beginning with "P00" are field names from the SF3 table):

1. % Minority

Non-minority = white alone, not Hispanic or latino (P007003)

Total population (P007001) (this is the sampled population headcounts, not actual)

% Minority = { [ (P007001 – P007003) / P007001 ] } * 100

Any blockgroup with a %Minority >= %25 was selected as an EJ population.

2. Income

•  Statewide median household income in 2000 (Dept. of Economic Development):  $46,947
•  65% of this value is $30,515. This is the number that was used for the criteria.

Any blockgroup that had a median household income in 1999 (P053001) less than this value was selected as an EJ population.

3.  English Proficiency

Linguistic isolation was used as the determining criteria here. It is defined in SF3 as follows:

Linguistic isolation. A household in which no person 14 years old and over speaks only English and no person 14 years old and over who speaks a language other than English speaks English ‘‘Very well’’ is classified as ‘‘linguistically isolated.’’ In other words, a household in which all members 14 years old and over speak a non-English language and also speak English less than ‘‘Very well’’ (have difficulty with English) is ‘‘linguistically isolated.’’ All the members of a linguistically isolated household are tabulated as linguistically isolated, including members under 14 years old who may speak only English.

Table P20 was used to establish this criteria.

• Total number of households in a given blockgroup (P020001)
• Linguistically Isolated Spanish speaking households (P020004)
• Linguistically Isolated Indo-European speaking households (P020007)
• Linguistically Isolated Asian and Pacific Island language speaking households (P020010)
• Linguistically Isolated “Other language” speaking households (P020013)

Total # of linguistically isolated households = S [ (P020004) + (P020007) + (P020010) + (P020013) ]
% of English Proficient households =  [ (P020001 - # of linguistically isolated households) /  P020001] * 100

Any value less than or equal to 75% was selected as an EJ population.

4.  Foreign-Born

• Total population (P007001)
• Number of foreign-born members of population (P021013)

% of population that is foreign-born = { 1 - [ (P007001 – P021013) / P007001 ] }* 100

Any blockgroup with a value of 25% or more was selected as an EJ population.

The resulting set of blockgroups was narrowed down by refining the query to remove the following:

• blockgroups with zero population.
• blockgroups which might have been selected erroneously due to the presence of a higher education institution (college student populations)
• blockgroups which might have been selected erroneously due to the presence of a correctional institution  (inmate populations)

Any time that one of the following schools or correctional facilities was found to be inside an EJ population polygon, the polygon was removed from the EJ selection.  (EXCEPTION:  polygons containing institutions located within Boston itself were not removed so as to not unfairly remove potential urban EJ populations)

These public educational institutions were geocoded and converted to point locations:
 

Berkshire Community College Bridgewater State College Bristol Community College Bunker Hill Community College Cape Cod Community College Fitchburg State College Framingham State College Greenfield Community College Holyoke Community College Massachusetts Bay Community College

Massachusetts College of Art Massachusetts College of Liberal Arts Massachusetts Maritime Academy Massasoit Community College Middlesex Community College Mt. Wachusett Community College North Shore Community College Northern Essex Community College Quinsigamond Community College Roxbury Community College

Salem State College Springfield Technical Community College University of Massachusetts Amherst University of Massachusetts Boston University of Massachusetts Dartmouth University of Massachusetts Lowell University of Massachusetts Medical Center Westfield State College Worcester State College

 
These private educational institutions were geocoded and converted to point locations:
 

American International College Amherst College Anna Maria College The Art Institute of Boston at Lesley University Assumption College Atlantic Union College Babson College Bay Path College Becker College Bentley College Berklee College of Music Boston College Brandeis University Clark University College of Our Lady of the Elms College of the Holy Cross Curry College Dean College

Emerson College Emmanuel College Endicott College Fisher College Gordon College Hampshire College Harvard University Hebrew College Labouré College Lasell College Lesley University Massachusetts College of Pharmacy & Health Sciences Massachusetts Institute of Technology Merrimack College Mount Holyoke College Mount Ida College New England College of Optometry New England Conservatory of Music

Newbury College Nichols College Northeastern University Pine Manor College Regis College Simmons College Smith College Springfield College Stonehill College Suffolk University Tufts University Wellesley College Wentworth Institute of Technology Western New England College Wheaton College Wheelock College Williams College Worcester Polytechnic Institute

 
These correctional facilities were geocoded and converted to point locations:
 

Boston Pre-Release Center Bridgewater State Hospital Massachusetts Boot Camp Massachusetts Treatment Center Old Colony Correctional Center Southeastern Correctional Center (closed 7/1/02) MCI- Concord

MCI- Framingham MCI-Cedar Junction MCI-Lancaster (closed 7/1/02) Bay State Correctional Center MCI-Norfolk Pondville Correctional Center MCI-Plymouth

MCI-Shirley (Medium) MCI-Shirley (Minimum) (closed 7/1/02) Souza Baranowski Correctional Center North Central Correctional Institution Northeastern Correctional Center Shattuck Hospital Correctional Unit South Middlesex Correctional Center

Finally, a few other polygons were arbitrarily removed due to an understanding of the population characteristics in a given blockgroup not agreeing with the conceptual idea of an “EJ population”.

The polygon attributes (EJ_POLY.dbf) for the shapefile distributed by MassGIS contain the following items:
 

ITEM NAME		TYPE / WIDTH		DESCRIPTION
AREA		F / 21		Area of polygon(s) in square meters
PERIMETER		F / 21		Perimeter of polygon(s) in meters
ACRES		F / 18		Area of polygon(s) in acres
BG_ID		C / 20		Blockgroup ID number, composed of a concatenation of 3-digit county FIPS ID + census tract # + blockgroup #
LOGRECNO		C / 8		Unique identifier of blockgroup within SF3. Can be linked to MassGIS Census 2000 Blockgroup index shapefile.
TOTAL_POP		N / 6		Actual headcount population of blockgroup
SAMP_POP		N / 6		Sampled headcount population of blockgroup. This value should be used because it is derived from SF3, where the rest of the demographic information was extracted from.
FOREIGN_BORN		F / 7		Percentage of blockgroup population that is foreign born
INCOME		N / 6		Median household income of the blockgroup in 1999 dollars
MINORITY		F / 7		Percentage of blockgroup population composed of minorities
ENGLISH		F / 7		Percentage of blockgroup population with English proficiency (all values of 75% or less meet EJ criteria)
FOR_FLAG		C / 1		Receives a value of “F” if it meets the EJ criteria foreign-born percentage
INC_FLAG		C / 1		Receives a value of “I” if it meets the EJ criteria for income
MIN_FLAG		C / 1		Receives a value of “M” if it meets the EJ criteria for minority percentage
ENG_FLAG		C / 1		Receives a value of “E” if it meets the EJ criteria for English proficiency percentage
EJ_SYM		C / 4		Concatenation of flag codes to aid in mapping symbolization of all EJ criteria combinations

The Area, Perimeter, and Acres fields were calculated by XTools for ArcMap 8.1 Version 3.0. The Sq_Mi field was calculated by multiplying the Acres field by 0.0015625.

MassGIS has prepared the following tables containing summary statistics:

• EJ_POLY_STATECRITSUM.dbf - statewide summary of the number of block groups, EJ acres, and EJ population for each unique combination of EJ criteria (based on the EJ_SYM item from the layer's attribute table)
• EJ_POLY_TOWNCRITSUM.dbf - for each town with EJ polygons, the unique combinations of EJ criteria (based on the EJ_SYM item from the layer's attribute table), the number of block groups, EJ acres, and EJ population
• EJ_POLY_TOWNSUM.dbf - for each town with EJ polygons, the number of block groups, EJ acres, and EJ population

MassGIS is maintaining this layer. Questions may be directed to Daniel Marrier at (617) 626-1237 or daniel.marrier@state.ma.us.

• OVERVIEW
• WHAT MASSGIS PROVIDES
• Census 2000 Blocks
• Census 2000 Block Groups
• Census 2000 Tracts
• Census 2000 TIGER Linework
• Census 2000 TIGER Water Bodies
• Census 2000 TIGER Towns
• Environmental Justice Populations
• CONSIDERATIONS WHEN USING TIGER DATA
• OTHER RESOURCES

 

Last Updated 5/30/2007
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