Table 2.

Hazard quotients (HQs) calculated using USEPA Office of Water National Recommended Water Quality Criteria Chronic Concentrations (CCCs).

CAS RN	Analyte	RL	N	EC	N Exceed	Avg HQ	Med HQ	Max HQ
7440-50-8	Copper	1000	25	Table 1	3–22*	0.52– 75*	0.21–6.2*	3.1–589*
7429-90-5	Aluminum	4000	25	87,000	13	1.5	1.1	11
7439-89-6	Iron	1000	25	1E6	2	0.33	0.19	1.7
7439-92-1	Lead	65	22	Table 1	1	0.23	0.16	1.7
7440-47-3	Chromium	1000	25	Table 1	0	0.041	0.011	0.56
7782-49-2	Selenium	1000	22	5000	0	0.21	0.20	0.31
16,887-00-6	Chloride	NA	23	2.3E08	0	0.096	0.077	0.23
7440-66-6	Zinc	500	25	120,000	0	0.033	0.028	0.19
7440-38-2	Arsenic	4000	25	150,000	0	0.057	0.032	0.17
84,852-15-3	Para- nonylphenol	1000	21	6600	0	0.15	0.15	0.15
7664-41-7	Ammonia (NH3)	12,159	25	1,900,000†	0	0.034	0.026	0.15
7440-02-0	Nickel	1000	25	52,000	0	0.024	0.019	0.042

Concentrations in ng/L. Method is the analytical method. RL is the reporting limit. N is the number of measurements passing quality control. EC is the effect concentration, which is set to the CCC in this table. NExceed is the number of measurements above the EC. Avg HQ is the ratio of the average (across N samples) concentration to the EC. Med HQ is the ratio of median (of N samples) concentration to the EC. Max HQ is the ratio of the maximum measured concentration to the EC.

^*Pairs of values listed for copper reflect use of Cu CCC Lo vs. Cu CCC Hi (see Table 1).

^†CCC for pH 7 at 20 °C.