Review of Trace Element Blank and Replicate Data Collected in Ground and Surface Water for the National Water-Quality Assessment Program, 1991–2002
By Lori E. Apodaca1, David K. Mueller2 and Michael T. Koterba3
Scientific Investigations Report 2006-5093, published 2006.
Table 6
Summary of trace-element environmental ground-water and surface-water data collected from 1991 to 2002.
[Ag, silver; As, arsenic; B, boron; Ba, barium; Be, beryllium; Cd, cadmium; Co, cobalt; Cr, chromium; Cu, copper; Fe, iron; Pb, lead; Li, lithium; mg/L, milligram per liter; Mn, manganese; Mo, molybdenum; Ni, nickel; Sb, antimony; Se, selenium; Sr, strontium; Tl, thallium; U, uranium; USEPA, U.S. Environmental Protection Agency; V, vanadium; Zn, zinc; µg/L, microgram per liter; <, less than; —, no data]
 AlSbAsBaBeBCdCrCoCuFePbLiMnMoNiSeAgSrTlUVZn
USEPA Drinking-Water Standard1²50–200³6³10³2,000³44600³5³1,00—      51,300²300515—      43004404100³50410044,000³2³30—      42,000
Common Reporting Level (mg/L)1.0    1.0    1.0    1.0    1.0    4.0    1.0    1.0    1.0    1.0    3.0    1.0    0.3    1.0    1.0    1.0    1.0    1.0    0.1    0.1    1.0    1.0    1.0    
 Ground Water
Number of samples2,927      3,016      3,308      3,129      3,032      1,120      3,132      3,144      3,033      3,182      4,066      3,128      895      5,036      3,070      3,083      3,063      2,995      1,310      542      3,548      835      3,092      
Median3.0    <1.0<1.054.3    <1.037.5    <1.01.1    <1.01.05   14      <1.06.74   7      <1.01.1    <1.0<1.0270      <0.1<1.01.4    4.89   
Maximum1,450      6.3    550      5,050      18      3,380      16      148      684      2,040      81,000      479      1,230      28,200      4,730      666      93.5    8      44,000      0.72   553      190      3,290      
Number equal to or greater than the USEPA drinking-water standard92      1      250      3      5      38      8      1      —      1      1,000      6      —      595      47      7      6      0      56      0      142      —      1      
Percent exceeding the USEPA drinking-water standard3.14   0.03   7.56   0.1    0.16   3.39   0.25   0.03   —      0.03   24.7    0.19   —      11.8    1.53   0.23   0.2    0      4.27   0      4.0    —      0.03   
 Surface Water
Number of samples3,171      2,471      2,441      3,445      3,030      1,853      3,612      3,158      2,468      3,473      4,929      3,388      665      2,170      2,773      3,250      3,094      3,329      1881      103      2,565      387      3,101      
Median13.0    <1.0<1.035      <1.054.3    <1.0<1.0<1.01.4    23.3    <1.013.9    7.77   <1.0<1.0<1.0<1.0140      <0.1<1.01.74   4.0    
Maximum20,600      16.9    284      410      11      4,200      18.2    89      53.2    871      54,100      39      230      1,460      157      216      150      8      3,490      2.22   74      54.8    4,450      
Number equal to or greater than the USEPA drinking-water standard492      15      126      0      1      61      88      0      —      0      227      9      —      23      8      3      13      0      0      1      27      —      52      
Percent exceeding the USEPA drinking-water standard15.5    0.61   5.16   0      0.03   3.29   2.44   0      —      0      4.61   0.2    —      1.06   0.29   0.09   0.42   0      0      0.97   1.05   —      1.68   
1U.S. Environmental Protection Agency, 2004. 2Secondary Drinking Water Regulation (SDWR): is a non-enforceable Federal guideline to address cosmetic or aesthetic effects of drinking water. 3Maximum Contaminant Level (MCL): the highest level of contaminant that is allowed in drinking water. 4Health Advisory (HA): is an acceptable drinking-water level for a chemical substance that is based on health effects information. HAs are not legally enforceable, but is a standard that serves as a guidance to assist Federal, state, and local officials. 5Action Level (AL): concentration of a contaminant that triggers treatment or other requirements that a water system must follow. For lead and copper, the action level is the level where 10 percent of the homes tested exceed the standard.