Licence conditions for pollution studies and reduction program

Licence conditions for pollution studies and reduction programs

Summary

Licence number:

555

Title:

Feasibility Assessment of Cooling Water System Modifications

Start date:

01 Apr 2015

Licence Condition
Environmental Improvement Program Background The Tallawarra Power Station does not use traditional antifouling chemicals to control biological growth in the primary water handling infrastructure. There are environmental benefits in not using these chemicals. Instead the site uses a Thermoshock process where cooling water is periodically heated and recirculated through the equipment at temperatures above 40 degrees. Rotating screens and fixed screens are used to remove fish and invertebrates from the cooling water system to a fish return channel during Thermoshock and at other times. Mortality rates for animals captured on the screens during the Thermoshock process are much higher than rates during normal power station operations. The Thermoshock Fish Mortality Investigation required under this licence reported that the Thermoshock process increased mortality in both fish and invertebrates by up to 33 and 21 per cent respectively. EPA has responded to two incidents of dead fish in the outlet channel in 2010 and 2014. Aim The EPA requires that Thermoshock procedures and engineering solutions be investigated and assessed for their effectiveness and feasibility to reduce mortality and damage to lake fish and invertebrates.
Requirements By 1 October 2015, the licensee must submit a Feasibility Assessment Report on options for revised operating procedures and cooling water system modifications to minimise the impacts of the Thermoshock process on Lake Illawarra fish and invertebrates. That is by excluding them, facilitating their passage away from the intake or through the system, and reducing heat shock. The assessment must make a summary evaluation of each option on a range of factors, including but not limited to, anticipated effectiveness, limitations, feasibility, and cost. Modifications must also be considered for adoption during routine operations (as well as during Thermoshock). These assessed modifications must include, but may not be limited to: i. applying turbulence (only) at the start of the Thermoshock process to allow fish time to escape before the introduction of heat, ii. introduction of ambient water to the beginning of the fish return channel to reduce thermal shock, iii. immersing the end of the fish return chute underwater to reduce predation, iv. removing jellyfish from the inlet canal, v. drum screens, chain screens, or other screening process in the inlet canal, vi. drum or rolling screens on the attemporation pump screen to remove animals; and vii. bubble, sound, light, and electrical screens on the attemporation pump inlet, penstocks, and inlet canal. Complete: EPA document DOC15/387908
By 3 months following EPA acknowledgement that the Report satisfies the above requirements, the licensee must submit a peer review report. The report must have been prepared by a suitably qualified and experienced professional approved in advance by the EPA. Note: EPA may add further requirements or conditions which require further assessment, implementation, or mortality studies. Due Date: 1 October 2015 (Part 1) and to be determined (Part 2)
By 21 October 2015, the licensee must nominate in writing to the EPA, two suitably qualified and experienced professionals to undertake a peer review of the Feasibility Assessment Report. The nominated practitioners must have experience in implementing flora and fauna management systems at power stations. The nominations must include the names of the actual professionals who will undertake the peer review, their qualifications, experience, professional association memberships, mailing address and contact phone number. If the EPA considers that neither of the practitioners nominated by the licensee are appropriate, suitably qualified, or experienced to carry out the work, and so notifies the licensee in writing, the licensee is required to nominate other more suitably qualified and experienced professionals. Complete: EPA document DOC15/417037