Laboratory studies were conducted to determine the effects of waste‐activated carbon (WAC), digested municipal sewage sludge (DMS), and animal manure (AM) on the sorption and leaching of alachlor [2‐chloro‐2′,6′‐diethyl‐N‐(methoxymethyl)acetanilide] in a Plainfield sandy soil (Typic Udipsamment). A total of 7500 mL of simulated rain water was applied to soil columns under three flow regimes with or without the waste amendments. The WAC most effectively reduced the mobility of alachlor, DMS was superior to AM. Amounts of alachlor recovered in the leachates, which ranged from <0.1% (2.1 t C ha−1 of WAC amended soil) to 74% (unamended soil) of that applied, depended upon the C loading rate of the wastes and upon the source of C‐containing species. The dissipation of alachlor from soil was greater when soil was amended with DMS and AM than when amended with WAC. Sorption of alachlor, which was determined by batch equilibration, was generally inversely related to its leaching in the amended soil, this observation suggested that sorption by soil organic matter controlled the mobility of alachlor. Application of C‐rich wastes to sandy coarse‐textured soils may be useful for reducing pesticide leaching to groundwater.

The potential for movement of sewage sludge‐borne trace metals beyond the zone of soil incorporation poses a real concern for society. To address this concern, we sampled an Aeric Ochraqualf (Blount Series) after 14 yr of massive, sludge additions (765 Mg ha−1 cumulative sludge applications, dry wt. basis). Cadmium, Zn, and Cu concentrations in each genetic horizon to a depth of 1.0 m were determined by atomic absorption spectroscopic analyses of 4.0 M HNO3 extracts. In addition, ped surfaces (cutans) and intra‐ped material (s‐matrix) from prismatic structural units of the lower B and upper C horizons were analyzed to determine the partitioning of trace metals in this highly structured profile. Cadmium concentrations in the subsoil of sludge‐treated areas were consistently and significantly higher (∼0.4 mg kg−1) than levels present in the control areas. Similarly, Zn concentrations in the 0.32 to 0.51 m region (Bt1) were increased (∼12 mg kg−1) with sludge applications; no increases in Cu levels were observed. Significantly more Cd (0.08 mg kg−1) was present in cutans removed from ped surfaces in the upper B horizon than was observed in the s‐matrix for sludge‐treated areas. Cutans also contained more sludge‐borne Zn than the associated s‐matrix. The evidence suggests that small amounts of sludge‐borne Cd and Zn moved out of the tillage zone into the subsoil of this highly structured agricultural soil over a 14‐yr period of massive sludge additions.

A sample of anaerobically digested Chicago municipal sewage sludge has been examined for mutagenicity by using a variety of biological assays with different genetic end points. The sludge clearly contains components that induce mutagenic responses in all of the species employed. Acetone extracts from the equivalent of 155 pL of neat sludge induced a doubling in the number of revertant colonies of the Ames Salmonella typhimurium strain TA98 after activation with mammalian microsomes. In situ and laboratory studies indicate the induction of point mutations in the germ cells of Zea mays. Cytogenetic damage was demonstrated by the increased frequency of micronuclei observed in meiotic cells of Tradescantia paludosa.

The relation between soil moisture and the effectiveness of preemergence herbicides for control of giant foxtail (Setaria faberii Herrm.) was studied under greenhouse conditions using surface soil from Drummer silty clay loam with 25, 31, and 37% moisture. Herbicides used were 2-chloro-4-ethylamino-6-isopropylamino-s-triazine (atrazine), ethyl N,N-dipropylthiocarbamate (EPTC), 3-amino-2,5-dichlorobenzoic acid (amiben), α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine (trifluralin), 2-chloro-N-isopropylacetanilide (propachlor), and 2-chloro-N-(methoxymethyl)-2',6'-diethyl-acetanilide (hereinafter referred to as CP 50144). The effectiveness of atrazine and EPTC was increased when soil moisture was raised from 25 to 31%, but no further increase was obtained at 37% moisture. Response to amiben increased linearly and response to trifluralin decreased linearly with increasing moisture. Increasing moisture within this range had little effect on propachlor or CP 50144.