OIL & GAS Human Health Risk Assessment Gas Terminal, UK
Project Summary
Human Health Risk Assessment Industrial Site, UK Heavy Metals Concentrations (mg/kg) Concentration (mg/kg)
5000 4000 3000 2000 1000 0 SS1
SS2
SS3
SS4
SS5
SS6
SS7
SS8
Surface Sample Location
C PM10 = (C/Q) × Q × (1 − V) × (
Key Project Elements •
Collection of Soil Samples
•
Identification of Contaminants of Concern
•
Assessment of Risk Posed to Human Health
•
Identification of Recommended Remedial Actions
Um 3 ) × F(x) × 10 3 Ut
CRA undertook an investigation at an industrial site to determine the chemical composition of a dust deposit covering an area of gravel hardstanding. The investigation included sampling of the surface gravels for laboratory analysis of metals and organic parameters. The investigation also comprised of trial pit excavation for the collection of soil samples to a depth of 3 metres. The analytical results indicated that the dust staining the gravels contained elevated concentrations of heavy metals including lead, and that the contamination was present in surface samples only. Due to the potential risk posed to human health from the inhalation of the metals contaminated dust deposit, CRA undertook a human health risk assessment, involving the derivation of site specific criteria for heavy metals. The risk assessment took into account the operational nature of the industrial site to determine exposure scenarios and adult worker receptors. This comprised assessment of the shift patterns, operational hours of the site and the amount of time spent working outside in the contaminated area. The main exposure scenarios assessed included inhalation of the dust and dermal contact. The known concentrations of heavy metals in the surface samples were screened against the CRA derived site specific criteria to identify the requirement for remedial action. This assessment identified that there was no current unacceptable risk to the human health of an industrial worker posed by the heavy metals concentrations recorded in the deposits. However, CRA recommended a number of remedial measures that were considered to be protective of the health of the site workers. These recommendations included the ongoing, regular monitoring of the heavy metal concentrations in the deposits to ensure concentrations remain below the site specific criteria. As a precautionary measure, remediation recommendations were made to identify the scale and extent of remedial actions in the event of the concentrations increasing to an unacceptable level.
Ref: PS0025a