EHS Support assisted Neilly Group to assess sediments and soils associated with the Magazine Creek stormwater detention ponds to facilitate draining, desilting, and drying of selected ponds at the site.
Test pitting was used to collect soil samples above and within the proposed depths of disturbance to assess if acid sulfate soils were present and determine the contamination status and associated waste classification. The investigation identified the presence of potential acid sulfate soils (PASS) within saturated soils beneath the wetland, but also identified that the soils contained sufficient acid neutralising capacity from shell grit to neutralise any acid generated from oxidation.
During execution of the project, EHS Support were asked if we could also assess sediments within the first detention pond to facility dredging and disposal. We were able to incorporate sampling of the pond sediments into the approved work scope with a variation only required for additional laboratory analysis. The sediments were assessed to comply with low-level contaminated waste due to elevated hydrocarbons and detectable concentrations of per- and poly-fluoroalkyl substances (PFAS).