Licence conditions for pollution studies and reduction program


  

Licence conditions for pollution studies and reduction programs

Summary
 
Licence number: 828
Title: PRP 33 - Implementation of Low pH Remediation Actions
Start date: 27 Aug 2012
 
Licence Condition
The licensee must remediate the low pH groundwater plume in the vicinity of the No. 1 Nitric Acid Plant (“NAP1”). The low pH plume is defined as groundwater at the premises in the vicinity and downgradient of the NAP1 Air Lift System that has a pH level of less than 6. The remediation may be guided by the report titled “Low-pH Groundwater, Nitric Acid Plant 1, Orica Kooragang Island, Remediation Action Plan (Revised)” prepared by Golder Associates and dated 29 June 2012 (“the Revised RAP”), but the licensee must include the following actions as part of the remediation:   (a)   By 1 October 2012 undertake further monitoring between MWNAP20 and MWNAP18S, as identified in the Revised RAP, to delineate the extent of the low pH groundwater plume.   (b)   Mass Reduction - By 1 January 2013 the licensee must commence extracting groundwater from the core of the low pH groundwater plume to reduce the mass of acidity in the aquifer to supplement natural attenuation processes. The extracted groundwater must be lawfully disposed. The licensee must continue to extract groundwater until the extracted water achieves the following remediation goals: (i)                  Removal of one pore volume of low pH groundwater (of the order of 750m3); or (ii)                Extracted groundwater exceeds pH 6 for a period of more than five (5) days of extraction after 50% of one pore volume has been extracted.   (c)   Monitored Natural Attenuation (i)      From 1 October 2012 undertake monthly monitoring of groundwater at monitoring wells identified in the Revised RAP for the following parameters: depth to water, pH, electrical conductivity, redox, dissolved oxygen and temperature. (ii)                From 1 October 2012 undertake six monthly monitoring of groundwater of at least one monitoring well upgradient of the low pH groundwater plume; at least one monitoring well within the core of the low pH groundwater plume; and at least two monitoring wells downgradient of the low pH groundwater plume for the following parameters: dissolved metals, major ions, nitrate and ammonia. (iii)               From 1 October 2012, provide a report to the EPA’s Regional Manager – Hunter every six months that provides the results and interpretation of monitoring undertaken as required by this Pollution Reduction Program; reviews the adequacy of the existing remediation strategy and recommends whether contingency remediation strategies are required to be implemented to prevent the migration of the low pH groundwater plume beyond the boundary of the premises and protect the environment. (iv)              Provide a Remediation Validation Report to the EPA’s Regional Manager – Hunter upon achieving the remediation objective of groundwater in the vicinity and downgradient of the NAP1 Air Lift System having been remediated to pH levels greater than pH 6.