Winter Maintenance Wash-Water Heavy Metal Removal Pilot Scale Evaluation

Table 1

Metal concentrations from the 3-hour oil/water separator study that was conducted at the Stark County garage on April 3, 2013. All samples below the detection limit have been identified with the less than sign and the detection limit. For the computation of the average, standard deviation, and median, all values below the detection limit were replaced with half the detection limit. Arsenic, cobalt, and selenium values are not shown below because more than half of the samples were below the detection limit. All units are µg/L (ppb).

Time	Al	B	Be	Cd	Cr	Cu	Fe	Li	Mn	Mo	Ni	Pb	V	Zn
7:00	4463	206	0.3	1	79	100	16828	13	1283	15	59	45	13	929
7:15	4106	170	0.4	1	132	93	19733	10	1185	14	69	44	14	1095
7:30	4940	182	0.5	3	158	324	23329	13	1366	15	112	140	16	2278
7:45	3322	168	0.3	1	145	111	17741	14	1056	12	57	33	11	1579
8:00	3114	175	0.3	2	152	142	21929	6	944	10	63	60	11	2105
8:15	546	134	<0.1	1	22	57	3752	6	288	7	28	<21	<1	423
8:30	2768	181	0.2	1	103	120	18571	11	711	11	54	42	10	913
8:45	2058	169	0.2	<0.9	70	108	12740	12	529	9	45	32	5	460
9:00	4723	205	0.3	2	125	269	26345	5	863	11	64	62	14	756
9:15	3784	185	0.3	2	106	257	18805	11	886	11	68	76	10	591
9:30	3418	201	0.2	2	118	179	27431	11	861	10	65	41	10	699
9:45	2749	190	0.2	1	90	136	18547	10	667	8	62	30	8	771
10:00	1358	178	0.1	<0.9	41	64	8667	9	400	6	37	<21	4	307
Average ± std. dev.	3181 ± 1250	180 ± 18	0.2 ± 0.1	1 ± 1	103 ± 40	151 ± 80	18032 ± 6360	10 ± 3	849 ± 315	11 ± 3	60 ± 19	48 ± 32	10 ± 4	993 ± 600
Median	3322	181	0.3	1	106	120	18571	11	863	11	62	42	10	771