Bench-Scale Flushing Experiments for Remediation of Hg-Contaminated Groundwater

Table 1

Characteristics of aquifer materials.

Sample	Perched aquifer (PA)	Lower aquifer (LA)	Detection limit
pH (1 : 2 soil : water)	4.24	6.35	0.01
Particle size
% gravel (>2 mm)	8.97	5.78	0.10
% sand (2.00 mm–1.00 mm)	18.3	14.8	0.10
% sand (1.00 mm–0.50 mm)	21.9	18.3	0.10
% sand (0.50 mm–0.25 mm)	11.2	9.76	0.10
% sand (0.25 mm–0.125 mm)	10.7	10.7	0.10
% sand (0.125 mm–0.063 mm)	5.23	6.86	0.10
% silt (0.063 mm–0.0312 mm)	7.17	8.37	0.10
% silt (0.0312 mm–0.004 mm)	10.6	14.8	0.10
% clay (<4 μm)	6.04	10.7	0.10
Texture	Sandy loam/loamy sand	Sandy loam
Organic/inorganic carbon
CaCO3 equivalent (%)	<0.80	<0.80	0.80
Inorganic carbon (%)	<0.10	<0.10	0.10
Total carbon (%)	0.1	<0.1	0.1
Total organic carbon (%)	0.10	<0.10	0.10
Metals
Aluminum (Al) (mg/kg)	31900	54100	50
Antimony (Sb) (mg/kg)	2.48	1.91	0.10
Arsenic (As) (mg/kg)	282	178	0.050
Barium (Ba) (mg/kg)	157	146	0.50
Beryllium (Be) (mg/kg)	0.61	1.34	0.20
Bismuth (Bi) (mg/kg)	<0.20	0.26	0.20
Cadmium (Cd) (mg/kg)	2.07	0.227	0.050
Calcium (Ca) (mg/kg)	1060	2430	50
Chromium (Cr) (mg/kg)	8.77	11.3	0.50
Cobalt (Co) (mg/kg)	50.1	12.8	0.10
Copper (Cu) (mg/kg)	85.9	52.9	0.50
Iron (Fe) (mg/kg)	35000	33900	50
Lead (Pb) (mg/kg)	47.1	27.1	0.50
Lithium (Li) (mg/kg)	55.6	25.6	5.0
Magnesium (Mg) (mg/kg)	2610	3010	20
Manganese (Mn) (mg/kg)	7790	2330	1.0
Mercury (Hg) (mg/kg)	0.196	0.0287	0.0050
Molybdenum (Mo) (mg/kg)	2.00	2.16	0.50
Nickel (Ni) (mg/kg)	13.9	8.70	0.50
Phosphorus (P) (mg/kg)	537	509	50
Potassium (K) (mg/kg)	1370	1520	100
Selenium (Se) (mg/kg)	<0.20	<0.20	0.20
Silver (Ag) (mg/kg)	0.38	0.18	0.10
Sodium (Na) (mg/kg)	270	250	100
Strontium (Sr) (mg/kg)	80.1	133	0.50
Sulfur (S), total (mg/kg)	1100	1400	500
Thallium (Tl) (mg/kg)	2.61	0.830	0.050
Tin (Sn) (mg/kg)	<2.0	<2.0	2.0
Titanium (Ti) (mg/kg)	774	787	1.0
Uranium (U) (mg/kg)	0.543	1.18	0.050
Vanadium (V) (mg/kg)	70.6	90.7	0.20
Zinc (Zn) (mg/kg)	358	407	1.0