Effect of liquid municipal biosolid application method on tile and ground water quality.
This study examined bacteria and nutrient quality in tile drainage and shallow ground water resulting from a fall land application of liquid municipal biosolids (LMB), at field application rates of 93,500 L ha(-1), to silt-clay loam agricultural field plots using two different land application approaches. The land application methods were a one-pass AerWay SSD approach (A), and surface spreading plus subsequent incorporation (SS). For both treatments, it took between 3 and 39 min for LMB to reach tile drains after land application. The A treatment significantly (p < 0.1) reduced application-induced LMB contamination of tile drains relative to the SS treatment, as shown by mass loads of total Kjeldahl N (TKN), NH(4)-N, Total P (TP), PO(4)-P, E. coli., and Clostridium perfringens. E. coli contamination resulting from application occurred to at least 2.0-m depth in ground water, but was more notable in ground water immediately beneath tile depth (1.2 m). Treatment ground water concentrations of selected nutrients and bacteria for the study period ( approximately 46 d) at 1.2-m depth were significantly higher in the treatment plots, relative to control plots. The TKN and TP ground water concentrations at 1.2-m depth were significantly (p < 0.1) higher for the SS treatment, relative to the A treatment, but there were no significant (p > 0.1) treatment differences for the bacteria. For the macroporous field conditions observed, pre-tillage by equipment such as the AerWay SSD, will reduce LMB-induced tile and shallow ground water contamination compared to surface spreading over non-tilled soil, followed by incorporation.
Lapen
D R
DR
Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada. lapend@agr.gc.ca
Topp
E
E
Edwards
M
M
Sabourin
L
L
Curnoe
W
W
Gottschall
N
N
Bolton
P
P
Rahman
S
S
Ball-Coelho
B
B
Payne
M
M
Kleywegt
S
S
McLaughlin
N
N
D003625:Data Collection; D008685:Meteorological Concepts; D012722:Sewage; D012987:Soil; D014867:Water; D014871:Water Microbiology
D012722:Sewage; D012987:Soil; D014867:Water