Tamar Valley Power Station, Bell Bay for Aetv Power
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ANNUAL ENVIRONMENTAL REVIEW (1 April 2015 to 31 March 2016) TAMAR VALLEY POWER STATION, BELL BAY FOR AETV POWER 10 January 2017 - Final (Signed) - Project No: 2946.002 SEMF PTY LTD 5 / 40 Molle Street, Hobart Tasmania 7000 T (03) 6212 4400 E [email protected] W www.semf.com.au ACN 117 492 814 - ABN 24 117 492 814 | F100 04, Revision 22, 4 September 2014 DOCUMENT ISSUE AUTHORISATION PROJECT: Annual Environmental Review (1 April 2015 to 31 March 2016) PROJECT NO: 2946.002 AUTHOR: Catherine Ford (BAgSc) PEER REVIEW: Fiona Keserue-Ponte (BAppSc Hons), CEnvP DATE PURPOSE OF ISSUE/NATURE OF REVISION REV REVIEWED BY AUTHORISED BY 25/07/2016 Preliminary Draft for internal review 0 Fiona Keserue-Ponte Catherine Ford (SEMF) (SEMF) 29/07/2016 Preliminary Draft for Client review 1 Kathy Shanley (AETV) Catherine Ford (SEMF) 04/08/2016 Preliminary Draft for EPA information Preliminary Provided to EPA Catherine Ford (SEMF) Draft Full AETV review pending – Not endorsed for release/review For information only 04/08/2016 Full Draft for Client review 2 Chris Ashley (AETV) Catherine Ford (SEMF) 15/08/2016 Full Draft for EPA review 3 EPA Catherine Ford (SEMF) 22/09/2016 Final for Client and Director EPA Final Catherine Ford (SEMF) Catherine Ford (SEMF) 10/1/2017 Signed Final for Director EPA Final Catherine Ford (SEMF) Catherine Ford (SEMF) (Signed) This document has been prepared in accordance with the scope of services agreed upon between SEMF Pty Ltd (SEMF) and the Client. To the best of SEMF’s knowledge, the document presented herein represents the Client’s intentions at the time of printing of the document. However, the passage of time, manifestation of latent conditions or impacts of future events may result in the actual contents differing from that described in this document. In preparing this document SEMF has relied upon data, surveys, analysis, designs, plans and ot her information provided by the client, and other individuals and organisations referenced herein. Except as otherwise stated in this document, SEMF has not verified the accuracy or completeness of such data, surveys, analysis, designs, plans and other information. No responsibility is accepted for use of any part of this document in any other context or for any other purpose by third parties. This document does not purport to provide legal advice. Readers should engage professional legal advisers for this purpose. SEMF Pty Ltd ACN 117 492 814 ABN 24 117 492 814 Telephone: (61 3) 6212 4400 Facsimile: (61 3) 6212 4475 Email: [email protected] Authorisation & Foreword: Page 1 of 2 Project: 2946.002 – AER (2015 – 2016) FINAL (Signed) EXECUTIVE SUMMARY AETV Power (AETV) is committed to operating the Tamar Valley Power Station (TVPS) at Bell Bay in an environmentally responsible manner, and in accordance with the conditions of the current Environmental Protection Notice No. 7898/1 (EPA, 2012a), and associated amendments. This Annual Environmental Review (AER) has been prepared for the reporting period 1 April 2015 to 31 March 2016 and submission to the Director Environment Protection Authority (Director EPA) to satisfy Condition RP1 of the EPN. Temporary Operational Changes & Maintenance In June 2014, the Mitsubishi Combined-Cycle Gas Turbine (CCGT) Unit was put into lay-up as it was surplus to State power generation requirements at the time, and the potential sale of the unit was considered. The CCGT remained in lay-up until 19th January 2016 when it was brought back on-line to address a power generation shortfall which occurred in Tasmania. The power generation shortfall occurred due to: . Lower than expected dam volumes; and . Bass Link cable fault. To ramp up Tasmanian power generation, operations on the TVPS site were increased where possible. During the AER reporting period turbine operations at the TVPS underwent a number of changes as part of the variations in operational demands on each of the turbines, including : . The Mitsubishi CCGT (Unit 201) was in lay-up for part of the period, then was been brought back on line; . The Rolls Royce Trent OCGT (Unit 104) was also brought back on line (after overseas repair works and onsite maintenance works); . The FT8s (Pratt & Whitney OCGT units 101A, 101B, 102A, 102B, 103A and 103B) were operated with and without the synchronous condensers, as power demands permitted, and as directed by maintenance work (with units being progressively being taken off-line and recommissioned); Other activities during this AER reporting period included: . Planned maintenance works (that had been on hold) associated with the Cooling Tower and Wastewater Retention Pond (WWRP) were undertaken, prior to each of these being brought back on line as part of the CCGT operations; and . TVPS operational shifts reverted to the former 24/7 basis. The State’s power shortfall was also met through the progressive establishment and operation of temporary diesel power generators at various locations within Tasmania, including on the neighbouring Hydro former Bell Bay Power Station (BBPS) site. In addition to maintenance which occurred on the TVPS turbines: . The Wastewater Retention Pond (WWRP) was taken off-line to enable desludging to be undertaken; . Accumulated sludge was removed from the WWRP (15 to 18 December 2015) in accordance with a methodology that had been approved by the EPA; Executive Summary: Page 1 of 2 Project: 2946.002 – AER (2015 – 2016) FINAL (Signed) . The sludge was tested for chemicals of potential concern, and was spread on a concrete pad on the neighbouring Hydro site for dewatering and later reuse on-site; and . While offline, the integrity of the WWRP liner was also checked for possible weaknesses that could be the source of undetermined water leaks that had been observed during the last reporting period. Monitoring of Potential Impacts Monitoring potential impacts of the operation was undertaken during the AER reporting period in accordance with the conditions of the EPN. The monitoring program included temporary variations to the frequency and parameters for wastewater and Donovans Bay. These variations were authorised based on the lower potential impact of the TVPS operation during the period when the CCGT unit was in lay-up (i.e. 4th June 2014 to January 2016). Monitoring reverted to that described in the EPN once the CCGT unit was back on line. Information regarding the operation of equipment, water supply utilisation, and the timing of monthly and quarterly monitoring (including wastewater, stormwater, Donovans Bay, near-shore water quality, stack testing and noise) during the AER reporting period is summarised in the timeline of operational and monitoring issues (Table 2). Water quality analysis of inline and grab samples showed general compliance of the operation with EPN regulatory limits, with only one exception; an exceedances of the EPN limit was recorded for Total Suspended Solids (TSS) in wastewater discharge upon start-up of the CCGT and WWRP after a prolonged period without discharge on 4 April 2015. Start-up of the CCGT was followed by a period of inconsistent operations, variable operational flows, and re- stabilisation of the WWRP after desludging. Monitoring results collected for March 2015 show the concentration of TSS in wastewater discharge returned to acceptable levels during the next monitoring event. The elevation has been attributed to ‘abnormal’ operations related to start-up, and is not therefore considered to be an exceedence of the limit set in the EPN, which are applicable to normal flow and operational conditions. TSS concentrations returned to levels within the EPN limit in the subsequent monitoring event for April. Two other parameters were recorded above their typical levels on the same first discharge occasion on 4 April 2015 and identified for further investigation by AETV; Total Petroleum Hydrocarbons (TPH) and Trihalomethanes (THM). In the absence of a prescribed EPN limit for these parameters, comparison with limits set for stormwater discharge (500 µg/L) shows them to be present at an acceptable level. AETV has observed the concentrations of TPH and THM over three monthly sampling events (February to April 2016) to be above previously recorded (typical) levels. AETV is taking a precautionary approach, and is continuing to monitor the potential correlation of TPH and THM, and their likely source investigated to improve understanding and management of operations. Conclusion AETV has been diligent in managing the power generation operations to ensure its compliance with EPN conditions, while also responding to State power shortfalls and co-ordinating planned equipment maintenance during this highly changeable AER reporting period (Refer to Table 2 for a summary of environmental monitoring and reporting compliance). Executive Summary: Page 2 of 2 Project: 2946.002 – AER (2015 – 2016) FINAL (Signed) CONTENTS 1. INTRODUCTION ............................................................................................................................ 1 1.1 OBJECTIVES AND SCOPE OF THE AER ................................................................................ 1 1.2 STRUCTURE OF THE AER.................................................................................................... 1 1.3 ACKNOWLEDGEMENTS ....................................................................................................... 2 2. ENVIRONMENTAL MONITORING ................................................................................................... 3 2.1 GENERAL ...........................................................................................................................