The Pikes Point Refuse Transfer Station has a Resource Consent to authorize the discharge of contaminants onto or into land from an industrial and trade process (Refuse Transfer Station). This consent requires a stormwater treatment device to be installed to treat the transfer station forecourt area.
Following discussions with Auckland Council and a detailed evaluation of alternative treatment systems, PPTS decided to install a treatment device called “Drainfix Clean”, which comprises a “treatment drain” partially filled with a proprietary treatment media providing both treatment and conveyance of stormwater. This technology was considered to be the best practical treatment option for the site, as it requires minimum space and shallow construction, can be retrofitted along the alignment of an existing drainage channel, and can achieve the desired treatment performance, including for dissolved heavy metals, based on overseas data from Drainfix installations, provided by the supplier.
Given this is new technology to New Zealand, PPTS decided to implement a treatment trial to test the performance, operation and maintenance requirements of this device before committing to larger scale implementation. Monitoring requirements were discussed and agreed with Auckland Council. This trial has recently been completed.
This paper provides an overview of the proposed treatment drain technology, a description of the trial, associated testing regime and trial results, and comments on potential applications of this new technology in New Zealand.