Environmental Injustice in the Urban Southwest: A Case Study of Phoenix, Arizona - Design with the Desert: Conservation and Sustainable Development - page 311

TABLE 17.2
Mean Sociodemographic Characteristics and Difference of Means t-Tests for Census Tracts with
Zero and Nonzero Hazard Density Indices

Type of Hazard

Variable CERCLIS LQG TRI TSDF CHDI

White
(percent)
Nonzero 65.8 64.4 58.1 52.4 67.5

Zero 80.1 77.1 79.6 72.8 81.9

t (sig.) 6.6 (.00) 5.8 (.00) 9.6 (.00) 4.6 (.00) 6.3 (.00)

Latino/a
(percent)
Nonzero

25.5 26.2 30.9 33.1 24.0

Without 14.0 16.9 14.9 20.2 12.9

t (sig.) 6.3 (.00) 4.9 (.00) 8.1 (.00) 3.4 (.00) 5.7 (.00)

Black
(percent)
Nonzero

4.1 4.7 5.6 7.0 4.1

Zero 2.9 2.7 2.4 3.3 2.4

t (sig.) 2.2 (.03) 3.7 (.00) 5.4 (.00) 2.5 (.02) 3.4 (.00)

Native
(percent)
Nonzero

2.0 2.1 2.6 5.1 1.8

Zero 0.7 1.0 0.8 1.2 0.6

t (sig.) 3.4 (.01) 2.3 (.02) 3.1 (.00) 1.7 (.09) 3.9 (.00)

Income ($)
Nonzero

32,649 32,347 30,544 25,716 34,292

Zero 43,444 40,440 40,473 37,622 43,616

t (sig.) 5.8 (.00) 4.9 (.00) 6.1 (.00) 5.6 (.00) 4.5 (.00)

Source: Bolin, B. et al., Environ. Plan . A , 34, 317, 2002.
t-values significant with p < .05 in bold; n = 466.

tracts contain 41% of all industrially zoned land in Phoenix although they constitute less
than 10% of Phoenix's total urbanized area. Further, this region had been host to a 20% of all
metro area industrial expansion since 1970. The placement of Interstate Highways 10 and
17 through portions of South Phoenix and bracketing the CBD has worked to concentrate
more recent industrial development in these already burdened areas. A major railroad
corridor, new freeways, and an expanding central city airport have each contributed to
the production of a region with the highest concentrations of hazardous industries and
contamination sites in the metro area. 22,23
Zoning data illustrate the problem of industrial encroachment on residential portions
of the 20 tracts. In metropolitan Phoenix, 1% of residentially zoned areas directly border
industrial zoning, in contrast to the 35% of neighborhoods in the study area which do
so. The presence of unbuffered industrial activity in the midst of low-income minority
neighborhoods has been a persistent feature of South Phoenix since the early twentieth
century* and that pattern largely remains today. As Table 17.3 illustrates, the percentage
of metropolitan population in the study area dropped from 7% in 1970 to 2.1% in 2000,

* See Luckingham. 24,25