Use of controlled release herbicides in waste burial sites

Conference · Wed Jul 01 00:00:00 EDT 1981

OSTI ID:5562121

Burton, F G; Cataldo, D A; Cline, J F; Skiens, W E

Controlled-release formulations of herbicides have been applied to the soil in the manner traditional for herbicides: on the surface or mixed into the top few inches of soil. The controlled-release formulation allows another option that we propose to use: to place herbicides, contained in controlled-release formulations, in a layer at least a foot below the surface of the soil, in order to prevent root penetration below that level. Ideally, the herbicide will prevent root tip cell division but will not translocate within the plant, thus assuring that the plant will survive, preserving the ground cover. Trifluralin is one of the herbicides which does not translocate and was chosen for use in this study. A number of applications for this technology are possible; particularly in waste management. In the present studies, we used two different forms of polymeric carrier/delivery (PCD) systems to investigate the controlled release of herbicides. In the initial study, a sheet was made of homogeneous mixtures of an individual polymer and trifluralin. We made several of these sheets, using a different polymer each time (with trifluralin) to compare release rates from the various polymers. We also fabricated cylindrical pellets in two sizes from mixtures of Profax/sup a/ PS-1600 polypropylene and trifluralin, formulated to determine the interaction of PCD systems with soil. Also developed is a trifluralin-releasing device with a theoretical effective lifetime approaching 100 years. The system was designed specifically to protect the asphalt layer or clay/aggregate barriers on uranium mill tailings piles. PCD devices composed of pellets could also be implanted over burial sites for radioactive and/or toxic materials, preventing translocation of those materials to plant shoots, and thence into the biosphere.

• Research Organization: Pacific Northwest Lab., Richland, WA (USA)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 5562121
• Report Number(s): PNL-SA-9503; CONF-810765-2; ON: DE82006167; TRN: 82-007833
• Resource Relation: Conference: 8. international symposium on controlled release of bioactive materials, Fort Lauderdale, FL, USA, 26 Jul 1981
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
60 APPLIED LIFE SCIENCES
HERBICIDES
USES
MILL TAILINGS
ENGINEERED SAFETY SYSTEMS
RADIOACTIVE WASTE DISPOSAL
ASPHALTS
INHIBITION
POLYMERS
REVEGETATION
ROOTS
SOILS
STABILIZATION
BITUMENS
MANAGEMENT
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
PESTICIDES
SOLID WASTES
TAILINGS
TAR
WASTE DISPOSAL
WASTE MANAGEMENT
WASTES
053000* - Nuclear Fuels- Environmental Aspects
553000 - Agriculture & Food Technology