Application of municipal sludge (biosolids) for agricultural purposes and groundwater nitrate concentrations

Conference · Mon Mar 01 04:00:00 EST 1993 · Geological Society of America, Abstracts with Programs; (United States)

OSTI ID:5582072

Welby, C W ^[1]

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1. North Carolina State Univ., Raleigh, NC (United States). Dept. of Marine, Earth and Atmospheric Sciences

One of the more popular means of handling sewage sludge from municipalities is its application to agricultural lands. A variety of crops are grown with the expectation that plants will utilize the nitrogen. However, a complex scenario allows some of the nitrate to move below root depth and eventually to the water table at depths of up to 30 ft. The City of Raleigh, NC injects sewage sludge ( residuals'', biosolids'') into soils derived largely from the Rolesville Granite in an area of typical rolling Piedmont topography. A 1975 background study of part of the site demonstrated differences in groundwater quality between areas farmed over a period of years and areas dominated by second-growth pine and harwood forests. Groundwater quality data collected semiannually between 1982 and 1988 show gradual buildup of nitrate in some fields; in others groundwater quality apparently remains unaffected by nitrate from the sludge. Monitoring well placement may play a role in these differences. Minimum time from the sludge application to an increase in groundwater nitrate is from 9 to 12 months. An ongoing study of a 12-acre field which lay fallow for a number of years prior to sludge application in 1990 demonstrates that some nitrate does move downward fairly rapidly, its movement being recorded in both the saprolite and groundwater. Comparison of nitrate content of groundwater from monitoring wells at a nearby dairy farm shows that normal agricultural practices may also increase the nitrate content of the shallow groundwater.

• OSTI ID: 5582072
• Report Number(s): CONF-9303211--
• Conference Information: Journal Name: Geological Society of America, Abstracts with Programs; (United States) Journal Volume: 25:2
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540220* -- Environment
Terrestrial-- Chemicals Monitoring & Transport-- (1990-)
540320 -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (1990-)
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
DEVELOPED COUNTRIES
ENVIRONMENTAL EFFECTS
ENVIRONMENTAL TRANSPORT
FARMS
GROUND DISPOSAL
GROUND WATER
HYDROGEN COMPOUNDS
LAND USE
MANAGEMENT
MASS TRANSFER
MATERIALS
MUNICIPAL WASTES
NITRATES
NITROGEN COMPOUNDS
NORTH AMERICA
NORTH CAROLINA
OXYGEN COMPOUNDS
POLLUTION
SEWAGE
SEWAGE SLUDGE
SLUDGES
USA
WASTE DISPOSAL
WASTE MANAGEMENT
WASTE PRODUCT UTILIZATION
WASTES
WATER
WATER POLLUTION