HVO 2009 Annual Environmental Management Report - Final

More documents

Recommendations

Info

Coal & Allied – Hunter Valley Operations 3.18 METHANE DRAINAGE/VENTILATION 3.18.1 Environmental Management and Performance During 2009 there were no methane drainage/ventilation occurrences at HVO. HVO are currently investigating options to test the viability of draining coal seams of methane ahead of opencut mining operations. The mine was part of an Australian Coal Association Research Programme (ACARP) evaluating methane content during 2008. Refer to Table 55 for details of the amount of coal seam gas released from mining operations. During 2008 Coal & Allied commenced a $6.8 million pilot programme to investigate the capture and use of coal seam methane (CSM) in advance of mining operations. The project involved the construction of four test drill wells for the capture of methane from MTW (Mount Thorley Warkworth) coal seams. One of these wells was drilled using a new drilling technique which will allow horizontal drill shafts to be formed which should allow for increased gas collection from a single well. The project aims to capture gas from seams up to 350m in depth in an effort to reduce the green house impact of the mine by reducing the emission of fugitive methane from the open cut. In 2010 the programme will move into test-production and monitoring of CSM to determine future applications across MTW and other Rio Tinto Coal Australia sites. 3.19 ACID ROCK DRAINAGE 3.19.1 Environmental Management In November 2007 Coal & Allied implemented an Acid Rock Drainage (ARD) and Mineral Waste Management Plan to help manage any problem materials and ensure proper disposal of interburden and washery rejected materials that are potentially acid forming. The management plan was developed after an independent review in 2005 found that, while there is not a significant ARD problem in the Hunter Valley, HVO has some interburden in West Pit that is identified as potentially acid producing. This material is limited to the Archerfield Sandstone which represents only six percent of mineral waste generated in West Pit. The management plan sets out to control the placement of potentially acid forming spoil materials and coarse rejects. Fine coal wastes are deposited into specially designed and constructed tailings storage facilities. A groundwater monitoring programme is included in the management plan to monitor the geochemical behaviour of HVO spoil and coal waste. Training of Coal & Allied staff is also a focus of the management plan, ensuring effective prevention, detection and management of potentially acid forming materials. 3.19.2 Environmental Performance Acid forming overburden and interburden are strictly managed on site through a detailed mining material tracking sheet and the mining Dispatch system to ensure these materials are disposed of in low level dumps in West Pit. The planning and procedures for daily management of material wastes are the responsibility of the Superintendent of mine planning and are communicated to production crews whenever the Archerfield Sandstone is being extracted. To ensure these plans are executed training is provided by Environmental Services to educate mine staff on what ARD is, how it can be prevented, what their role in prevention is and what is done on site to identify potential acid forming material. ARD and Mineral Waste training sessions were conducted at HVO during February 2008. The ARD and Mineral Waste management systems at HVO were subject to a Rio Tinto HSE Standards audit in November 2009. There were no non-conformances identified during the audit however three observations related to ARD and mineral waste management made during the audit will be addressed in 2010. AEMR 2009 147
Coal & Allied – Hunter Valley Operations Geology Management The geochemical sampling programme detailed in the Acid Rock Drainage and Mineral Waste Management Plan, to better quantify the net acid generating potential in the HVO seams and interburdens, has continued during 2009. Sampling of coarse rejects and tailings from the two HVO CPPs has been undertaken while high sulphur coal is being processed. The results of this sampling programme will be utilised during a review of the ARD and Mineral Waste Management Plan planned for the second quarter of 2010. Prevention of geotechnical failures at HVO are factored into the design phase of individual pits. Monitoring is then conducted during the construction of each pit to ensure both compliance to design, and the engineering itself is sound. Any hazards identified during the construction phase, captured by daily inspections, are recorded in the Monthly Geotechnical Hazard report. The potential for environmental impact from a geotechnical failure is considered low. The key geotechnical risks at HVO are detailed in the Management Plan for Geotechnical Hazards. This document is currently undergoing an audit and update to include new dump and slope management plans. 3.20 PUBLIC SAFETY 3.20.1 Environmental Management Public safety at HVO is managed primarily through the implementation of Coal & Allied safety standards and procedures, with daily security inspections. Fencing, signposting, restricted access areas and locked external gates form part of the safety measures to ensure the safety of the public. In addition, there is no public access from the mine entrance to pit areas, as part of the constraint on public access. HVO has a security service contract covering the entire operation and surrounding areas. This service consists of nightly inspections of the mining lease area to ensure the safety of all persons in the mine vicinity, and to ensure there are no breaches of security. Security Inspections are undertaken in the Mine, Maintenance, CPP, magazine area, administration and all exterior gates of the mine lease area. 3.20.2 Environmental Performance During the reporting period, there were no incidents involving members of the general public being detected in vehicles on the HVO site. 3.21 REPORTABLE ENVIRONMENTAL INCIDENTS 3.21.1 Environmental Management All environmental incidents are now ranked using a qualitative risk assessment matrix, based on the maximum reasonable consequence and likelihood. 3.21.2 Environmental Performance Five incidents were required to be reported to governing authorities as a result of breaches to development consents or the HVO EPL. The details of these five incidents are outline below, with a summary of all incidents provided in Appendix 3. Incident 1000037320 On Friday 23 January 2009 at 10:00am a discharge of mine water was discovered at HVO Dam 17N. During a routine inspection of the area, a pump was found to be leaking into a collection sump, the sump in turn filled with mine water and was found to have flowed through an overflow pipe into the nearby Farrells Creek. The volume of water that entered Farrells Creek was estimated to be no more than 0.2ML. The water was found to extend no further than 0.5km downstream and was contained within Hunter Valley Operation’s EPL Boundary. Water samples taken after the event found that water downstream of the leak was similar to that of the stored water in the dam, but not dissimilar to levels found in Farrells Creek in the past, and as such determined to be of negligible environmental impact. This is not a licensed discharge point under the HRSTS so the leak was AEMR 2009 148
Page 1 and 2:
Annual Environmental Management Rep
Page 4 and 5:
Coal & Allied - Hunter Valley Opera
Page 6 and 7:
Page 8 and 9:
Page 10 and 11:
Page 12 and 13:
Page 14 and 15:
Page 16 and 17:
Page 18 and 19:
Page 20 and 21:
Page 22 and 23:
Page 24 and 25:
Page 26 and 27:
Page 28 and 29:
Page 30 and 31:
Page 32 and 33:
Page 34 and 35:
Page 36 and 37:
Page 38 and 39:
Page 40 and 41:
Page 42 and 43:
Page 44 and 45:
Page 46 and 47:
Page 48 and 49:
Page 50 and 51:
Page 52 and 53:
Page 54 and 55:
Page 56 and 57:
Page 58 and 59:
Page 60 and 61:
Page 62 and 63:
Page 64 and 65:
Page 66 and 67:
Page 68 and 69:
Page 70 and 71:
Page 72 and 73:
Page 74 and 75:
Page 76 and 77:
Page 78 and 79:
Page 80 and 81:
Page 82 and 83:
Page 84 and 85:
Page 86 and 87:
Page 88 and 89:
Page 90 and 91:
Page 92 and 93:
Page 94 and 95:
Page 96 and 97:
Page 98 and 99:
Page 100 and 101:
Page 102 and 103:
Page 104 and 105:
Page 106 and 107:
Page 108 and 109:
Page 110 and 111:
Page 112 and 113:
Page 114 and 115:
Page 116 and 117: Coal & Allied - Hunter Valley Opera
show all

HVO 2009 Annual Environmental Management Report - Final

Create successful ePaper yourself

Delete template?

Save as template?