2011) generated environmental cleanup regulations, including the Comprehensive
Environmental Response, Compensation, and Liability Act (CERCLA) for abandoned sites and corrective action of the Resource Conservation and Recovery Act
(RCRA) for active sites and generated remediation engineering (Applegate and
Laitos 2006; US EPA 2018a). Progressively, hundreds of thousands of sites with
different degrees of contamination have been identified in the US. Table 2.1 summarizes prevalent contaminants of concern (COCs) at National Priorities List (NPL)
sites. In 2018, the NPL featured 1566 contaminated sites. 381 of them have been
sufficiently restored, posing a minimal risk, and proposed for site deletion (US EPA
2018b). Nevertheless, over the next decades, cleanup research and business will still
be active in restoring the remainder as well as newly spilled sites. The US EPA
Table 2.1 Prevalent contaminants of concern (COC) at National Priorities List (NPL) sites
(adapted from Siegrist et al. 2011 with permission)
Contaminant of
concern (COC)
Priority as a COC at US
hazardous waste sites
(ATSDR
a ranking)
Prevalence at US NPL sites
US
drinking
water
standard
(μg/L)
Number of
NPL sites
with COC
present
Sites with COC
present as a % of
total NPL sites
Arsenic
1
1149
68
10
Lead
2
1272
76
15
Mercury
3
714
49
2
Vinyl chloride
4
616
37
2
Polychlorinated
biphenyls
5
500
31
0.5
Benzene
6
1000
59
5
Cadmium
7
1014
61
5
Polycyclic aromatic
hydrocarbons
8
600
42
–
Benzo(a)pyrene
9
–
–
0.2
Chloroform
11
717
50
100
Trichloroethene
16
852
60
5
Chromium
18
1127
68
100
Tetrachloroethene 33
771
54
5
Pentachlorophenol 45
313
20
1
Carbon
tetrachloride
47
425
26
5
Xylene (total)
58
840
51
10,000
Toluene
71
959
60
1000
Methylene
chloride
80
882
56
5
1,1,1trichloroethane
97
823
50
200
Ethylbenzene
99
829
49
700
a ATSDR Agency for Toxic Substances and Disease Registry
2 Nanoscale Zero-Valent Iron Particles for Water Treatment: From Basic. . .
21
Environmental Response, Compensation, and Liability Act (CERCLA) for abandoned sites and corrective action of the Resource Conservation and Recovery Act
(RCRA) for active sites and generated remediation engineering (Applegate and
Laitos 2006; US EPA 2018a). Progressively, hundreds of thousands of sites with
different degrees of contamination have been identified in the US. Table 2.1 summarizes prevalent contaminants of concern (COCs) at National Priorities List (NPL)
sites. In 2018, the NPL featured 1566 contaminated sites. 381 of them have been
sufficiently restored, posing a minimal risk, and proposed for site deletion (US EPA
2018b). Nevertheless, over the next decades, cleanup research and business will still
be active in restoring the remainder as well as newly spilled sites. The US EPA
Table 2.1 Prevalent contaminants of concern (COC) at National Priorities List (NPL) sites
(adapted from Siegrist et al. 2011 with permission)
Contaminant of
concern (COC)
Priority as a COC at US
hazardous waste sites
(ATSDR
a ranking)
Prevalence at US NPL sites
US
drinking
water
standard
(μg/L)
Number of
NPL sites
with COC
present
Sites with COC
present as a % of
total NPL sites
Arsenic
1
1149
68
10
Lead
2
1272
76
15
Mercury
3
714
49
2
Vinyl chloride
4
616
37
2
Polychlorinated
biphenyls
5
500
31
0.5
Benzene
6
1000
59
5
Cadmium
7
1014
61
5
Polycyclic aromatic
hydrocarbons
8
600
42
–
Benzo(a)pyrene
9
–
–
0.2
Chloroform
11
717
50
100
Trichloroethene
16
852
60
5
Chromium
18
1127
68
100
Tetrachloroethene 33
771
54
5
Pentachlorophenol 45
313
20
1
Carbon
tetrachloride
47
425
26
5
Xylene (total)
58
840
51
10,000
Toluene
71
959
60
1000
Methylene
chloride
80
882
56
5
1,1,1trichloroethane
97
823
50
200
Ethylbenzene
99
829
49
700
a ATSDR Agency for Toxic Substances and Disease Registry
2 Nanoscale Zero-Valent Iron Particles for Water Treatment: From Basic. . .
21