TRAPPS™ for Small Arms Firing Range Remediation

Due to the nature of their operation, small arms firing ranges (SAFRs) are characterised by elevated levels of a range of heavy metals. SAFRs may either exhibit a concentrated (e.g. impact berm behind a fixed target) or a diffuse (trap and skeet range) pattern of metal release. Lead is the primary contaminant released, although metals such as antimony, copper, zinc and arsenic are also often present.

Discharged bullets which accumulate in soil or impact berms at the SAFR can be either intact or fragmented upon impact. Over time, weathering and corrosion can transform elemental lead to more soluble lead salts such as cerrusite (PbCO3) and hydrocerrusite (Pb3(CO3)2OH. These Pb corrosion products are not stable and can readily form water soluble Pb2+ ions. This can result in leaching and migration of Pb to surrounding groundwater and surface water.

TRAPPS™ is very effective for the stabilisation of SAFR soils as it offers the following key advantages;

Case Data

TRAPPS™ has been demonstrated to be very effective at stabilising Pb in soil obtained from a number of SAFR sites in the UK and USA. The data presented below is from a site in New York. Total soil metal was 46,000mg.kg-1.

Following treatment there were two possible options for the contaminated soil; disposal to landfill or retention and reuse on site.

TCLP data from the TRAPPS™ treated soil showed a 99.8% reduction in leachable lead when compared to the untreated soil (3.3mg.L-1 as opposed to 1400mg.L-1). The treated material passed the TCLP landfill criteria (5mg.L-1).

SPLP data was used to demonstrate the reduction of leachable Pb for material to be retained and reused on site. SPLP Pb in the unamended sample was 8mg.L-1 as opposed to 0.037mg.L-1 in the TRAPPS™ treated soil.

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