CONTAINMENT OF LEAD MATERIAL
This guidance addresses the appropriate use and the key design elements of onsite engineered containment systems, where this is an option for lead-bearing material collected during the process of remediating lead contaminated sites.
a. Many lead remediation projects have faced serious challenges in achieving an acceptable long term solution for disposal of contaminated material which cannot be recycled. Agreement on the final disposal solution is often the most long drawn out aspect of the process.
b. For material which cannot be reprocessed, reused or managed adequately in-situ, secure containment is normally the preferred option. Containment involves engineered structures which isolate the waste securely and reduce risk to an acceptable level over the long term. Containment may be in an purpose built facility or may involve transport to an existing engineered landfill or hazardous waste facility, if feasible.
c. The primary objective of containment is to prevent direct contact with or distribution across the environment of the lead material. Protection of ground water is a key priority.
d. The waste material is broadly homogeneous because lead is the main contaminant and this allows the material to be managed in a “mono-landfill” designed specifically for this waste or in a similar “mono-cell” within a larger landfill. Regulations in the USA and the UK, among other countries, allow for and even encourage this approach.
e. A key issue is the selection of the site for the containment, with the most important aspects usually being local acceptance and protection of groundwater. On-site containment should always be considered and has an inherent attraction by linking the containment to the local problem.
f. A plausible long-term use for land where lead waste is buried under a secure cap is for playing fields or similar public open space. This is consistent with the increasing use of closed municipal landfills for such purposes. In some cases, sites may be developed for commercial or industrial uses such as parking areas.
g. There are a number of key practical design details that should be taken into account. This Guidance sets out some of these but does not address them in detail: qualified technical advice should be sought.
h. The level of effort and cost put into the remediation project should be proportional to the overall objectives of the remediation and to the levels of risk reduction to be achieved by carrying it out. Determination of remediation clean-up targets and selection of options must be carried out by experienced and competent personnel, in consultation with the local community and the appropriate regulatory authorities.
Download as pdf: GUIDANCE on Onsite containment of lead Jan 2014