Animal Burrowing Attributes Affecting Hazardous Waste Management

Abstract

/ Animal burrowing is critical to the formation of soils and contributes to the interface between geological materials and organic life. It also influences the management of hazardous materials at nuclear waste facilities and elsewhere. For example, residues and waste products from the production of nuclear weapons are released onto the ground surface and within engineered burial structures. Soil bioturbation has exposed radionuclides and other hazardous materials to wind and rain, thereby risking inhalation and injury to humans and wildlife on and off site. Soil bioturbation can expand soil depths and spatial distributions of the source term of hazardous waste, potentially increasing chronic exposures to wildlife and humans over the long term. Ample evidence indicates that some of the large quantities of hazardous materials around the world have been released from soil repositories, where they have also contaminated and harmed biota. Key burrowing parameters influencing these outcomes include the catalog of resident species, and their abundance, typical burrow volumes (void space created by soil displacement), burrow depth profiles, maximum depth of excavation, constituents and structural qualities of excavated soil mounds, and proportion of the ground covered by excavated soil. Other important parameters include rate of mound construction, depth of den chambers, and volume of burrow backfill. Soil bioturbation compromised the integrity of some hazardous waste management systems using soil, but the environmental impact remains largely unknown. Designers and operators of waste management facilities, as well as risk assessors, need to understand how burrowing animals influence hazardous waste storage.KEY WORDS: Burrowing; Environmental impact; Radioactivity; Risk; Soil bioturbation; Hazardous waste

Compliance Assessment Document for the Transuranic Wastes in the Greater Confinement Disposal Boreholes at the Nevada Test Site, Volume 2: Performance Assessment

“…Much of the information provided here was taken from three summaries of animal burrowing activities Winkel et al, 1995;Smallwood et al, 1998]. Two of these studies Winkel et al, 1995] specifically address the potential impact of animals on waste disposed at the NTS.…”

Factors influencing burrow length and depth of ground-dwelling squirrels

“…Burrowing activities also are important for land managers. Soil excavation can expose buried hazardous waste (Smallwood et al 1998), remove the protective earth covering from ammunition bunkers at military installations (Loredo-Prendeville et al 1994), and disturb archaeological sites (Brocek 1986), and the existence of burrows can threaten the integrity of earthen dams and levees (Bayoumi and Meguid 2011). Burrow dimensions of ground squirrels have not been summarized, and factors that influence the length and depth of ground squirrel burrows are poorly understood.…”

Micromorphological investigations into root penetration in a landfill mineral cap, Hertfordshire, UK

“…Modern containment landfills are usually capped with a combination of mineral (generally clay) and artificial layers to restrict water ingress from the atmosphere into the wastes, and landfill gases from the wastes into the atmosphere. To ensure the maximum longevity of the landfill cap, it is usually covered by a soil cover, of sufficient thickness to prevent exposure to frost damage (Zimmie and La Plante, 1990; Office of Solid Waste and Emergency Response, 1993), animal burrowing (Smallwood et al, 1998;Butt et al, 2004) and plant root penetration, particularly from trees (Fang, 1995;Rawlinson et al, 2004). In order for trees to be successfully grown on landfill sites, and to minimise the risk of consequent pollution, it is vital to ensure that roots do not penetrate, and subsequently weaken, clay materials used to cap the underlying landfilled wastes (Dobson and Moffat, 1993;Handel et al, 1997).…”