Newcastle Validation Consultant

⁠⁠⁠The Principal wishes to have the Clyde Street Remediation project carried out for the purposes of environmental protection, in order to address Contamination identified at the Site, subject to necessary approvals, Remediation Works and other management activities.

The former Newcastle Gasworks Site is located at 1 Chatham Road, Hamilton North, NSW (the “Site”) approximately 165 km north-east of Sydney. The Newcastle Gas Company (now Jemena) operated the Site as a gasworks from 1913 to 1985. The gasworks produced ‘town gas’ via the coal carbonisation process. This process involved heating crushed bituminous coal in a sealed, oxygen-deficient chamber (the retort) to generate gas, with the by-products of coke, tar and ammonia. Naphtha replaced coal as the feedstock material in the late 1960s, and coal gasification was phased out at that time. Historical gasworks-related operations and waste disposal activities have contaminated the soil and groundwater at the Site.

The Site has been vacant since production of town gas ceased, although the southern portion of the Site was occupied by Elgas until mid-2014 for gas storage and bottling purposes.

The NSW EPA has declared the Site as being significantly contaminated under Section 11 of the Contaminated Land Management Act 1997. Jemena are currently managing the Contamination through implementation of a Management Order (MO), which required a RAP to be prepared for the site. This RAP was developed to meet the requirements of the MO and to present a remediation strategy suitable to address the potential risks to human health and the environment posed by the Contamination, to allow ongoing commercial/industrial use of the site under the current land use zoning, and to prevent (to the extent practicable) the migration of contaminants to Styx Creek, which runs parallel to the Site’s eastern boundary.

The remediation, in general will involve implementation of a cap and contain remedial strategy, involving construction of a subterranean low permeability barrier wall and placement of a capping system across the extent of the Site. Residual Contamination remaining at the Site will be managed implementation of a Long-term Environmental Management Plan (LTEMP) for the Site post Remediation.

Recent Site investigations have identified elevated concentrations of:
Investigations at the Site indicated that separated phase gasworks waste and tar (SPGWT) contamination within the soil and groundwater is one of the key drivers for remediation. The investigations at the Site have also identified contaminants of potential concern (CoPC), which exceed the adopted relevant health and/or ecological assessment criteria. These CoPC’s are detailed in Section 4.2.3 of the RAP and include:
Petroleum hydrocarbons, monocyclic aromatic hydrocarbons (benzene, ethylbenzene, toluene and xylenes, collectively referred to as BTEX), polycyclic aromatic hydrocarbons (PAHs) and cyanides in soils;
* Ammonia, zinc, cyanides (generally present as complexed cyanides), thiocyanate, phenols, BTEX, naphthalene and petroleum hydrocarbons in groundwater;
* BTEX, naphthalene and petroleum hydrocarbons in soil vapour;
* Low concentrations of the phenolic compound 2,4-dimethylphenol, naphthalene, ammonia, nitrate and in Styx Creek surface water; and
* Asbestos, generally occurring as fibre cement sheet fragments mixed with soils.

A detailed site history, extent of Contamination, proposed Remediation approach, etc. are detailed in the RAP. The appointed-Site Auditor has reviewed the RAP and “considers that the RAP is appropriate in relation to the contamination issues outlined in the Management Order”.

The Remediation Works described in this document is the design and construct of the preferred remediation option as outlined in the Remedial Action Plan (RAP) prepared by JBS&G Australia Pty Ltd (JBS&G), dated 21 November 2017.