Section Four
WASTE MANAGEMENT
B. LANDFILLS AND LAND APPLICATION
23    CLOSURE OF A RCRA SURFACE IMPOUNDMENT AS A
LANDFILL BY IN-SITU STABILIZATION
Neil A. Leipzig, Environmental & Safety Manager
Solvay Animal Health, Incorporated
Charles City, Iowa 50616
INTRODUCTION
Solvay Animal Health, Incorporated (SAH) is a privately owned manufacturing facility located
in Charles City, Iowa. Operations began at the facility in 1951. SAH formerly utilized a surface
impoundment (hereinafter, Impoundment) as a storage/equalization basin for chemical production
wastewater from organic and organo-arsenic compounds production activities. The Impoundment
ceased operation during November, 1986 in accordance with the Resource Conservation Recovery
Act's regulatory timetable for hazardous waste surface impoundments.
The Impoundment was approximately 100 feet wide by 300 feet long with a maximum capacity of
approximately 1,000,000 gallons. The unit was constructed in 1965 directly atop the surface of an
underlying weathered limestone formation. It is lined with a continuous layer of compacted clay
averaging 26 inches in thickness with an average coefficient of permeability of less than 1 x 10"8 cm/
sec. Over the years the unit had received a RCRA hazardous D004 (arsenic) wastewater which
subsequently had deposited a D004 characteristic sludge within the Impoundment. Table I presents a
EP Toxicity metals characterization of the Impoundment's native sludge. At the commencement of
closure activities the Impoundment contained in excess of 2100 yd3 of sludge with an average total
Table I.    Surface Impoundment Native Sludge Characterization
Sample 1
Sample 2
Sample 3
EP Toxicity
Total          EP
Total          EP
Total          EP
Maximum Allowable
Parameter
(mg/kg)     (mg/L)
(mg/kg)     (mg/L)
(mg/kg)     (mg/L)
Concentration
Arsenic
1,170        14.2
1,860        13.8
2,000        24.8
5.0
Barium
2,680         0.065
2,610         0.164
2,760         0.55
100.0
Cadmium
4.04    0.0034
4.73     0.0005
3.51     0.024
1.0
Chromium
135       <0.10
190      <0.10
105       <0.10
5.0
Lead
94.5    < 0.001
205      < 0.001
168         0.004
5.0
Selenium
<0.20 < 0.002
<0.20 < 0.002
<0.20 < 0.002
1.0
Silver
8.3    <0.06
10.2   <0.06
11.3    <0.06
5.0
Mercury
38.9      0.0002
35.4   < 0.0002
16.6   < 0.0002
0.2
Total Solids
(105°C)
15.3
18.9%
32.5%
Total Solids
(550°C)
2.8%
4.7%
8.2%
Density
(g/mL)
1.09
1.09
1.229
PH
8.44
8.53
9.04
Composite samples of the sludge were collected at three
areas across the Impoundment using a
Wilco Hand Corer.
49th Purdue Industrial Waste Conference Proceedings, 1994 Lewis Publishers, Chelsea, Michigan 48118. Printed in
U.S.A.
215