Appx A3 Construction Photos, Nov 2012-Jan 2013 compressed

CONSTRUCTION OF THE TAILINGS STORAGE FACILITY

02 Nov 12 DSC5557Detail of intersection of a runoff flow channel with the main flow channel in the base of the western side valley.

02 Nov 112 DSC5562Liner deployment on upstream slope of dividing embankment at the beginning of November. Note extents of liner in SE corner of TSF.

Akyem TSF Construction Report – Appendix A3 – Construction Photos – November 2012 to January 2013 1


05 Nov 12 DSC5634Progress of liner deployment and construction of flow channel FC6 in SE corner of TSF basin.

10 Nov 12 DSC5685LCRS drain being extended down the valley ahead of flow channel construction and liner deployment, with collector drain construction following.



09 Nov 12 DSC5673Soil liner, HDPE liner and drains construction in progress in western side valley.

13 Nov 12 DSC5709Soil liner processing in progress in soil liner area SL80 in east central section of TSF basin.



19 Nov 12 DSC5778First of 3 lines of LCRS drains in lower east side of TSF, under flow channel FC2, the main eastern drainage channel.

24 Nov 12 DSC5854Third LCRS drain under FC2 in lower east side of TSF.



24 Nov 12 DSC5829Eight rolls of liner deployed on embankment slope and adjacent section of valley floor, SL84, in SE corner of TSF.

28 Nov 12 DSC5899SE corner of TSF at the end of the month.



28 Nov 12 DSC5894Three rolls of liner deployed in western side valley to extend lining of flow channel C8 and to tie in flow channel WC2.

28 Nov 12 DSC5895Soil liner areas SL87, smooth rolled, and SL89, above, on eastern side of TSF basin.



03 Nov 12 DSC5599NE lake at the beginning of November, extensively flooded after a very wet month in October.

27 Nov 12 DSC5881Flooded extents of NE lake reduced by drainage through TSF W diversion, by pumping into water trucks and by filling the area with unsuitable material.



27 Nov 12 DSC5880NE embankment completed with wearing course and safety berms. The Group 5 pipeline crew is laying out and welding the decant return pipeline.

29 Nov 12 DSC5904Temporary decant tower established at TSF with 5 of the 7 precast sections set in place and with the Zone G rockfill aound the tower and the Zone E1 rockfill further out around the toe of the structure.



29 Nov 12 DSC5910Flow channel FC2 being cut to floor level for importation of soil liner in the lower east side of the TSF. The 3 LCRS drains are already installed under this section of the flow channel.

29 Nov 12 DSC5912West abutment of dividing embankment with ~30,000 m3 of fill placed in November.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, EMBANKMENTS

05 Dec 12 DSC6017West abutment fill well advanced at dividing embankment.

09 Jan 13 DSC6119W abutment fill nearing completion and E abutment fill raised as well.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, EMBANKMENTS

22 Jan 13 DSC6221Approx 80,000 m3 of fill remain to be placed to close the gap in the dividing embankment, of which ~15,000 m3 can be placed on the abutments to extend the completed length of the crest prior to closing the drainage gap.

23 Jan 13 DSC6227NW embankment crest prepared for excavation of anchor trench and deployment of HDPE liner.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, DECANT TOWERS

11 Jan 13 DSC6129Protective cover fill nearing completion on textured VLDPE liner for base of permanent decant tower, base RL175. The temporary decant tower, RL168 to RL175 is completed in the background.

18 Jan 13 DSC6189Base slab for permanent decant tower completed by Consar for WBHO. As the base is at ~RL172, above the minimum level for closure of the TSF basin, construction of the decant tower was deferred into February to concentrate on work in the low-lying areas of the TSF basin.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, UNSUITABLE MATERIAL

05 Dec 12 DSC6016Excavation of mud washed in on top of previous backfill in lower extents of western stream course.

09 Jan 13 DSC6120Removal of mud nearing completion in lower west side of TSF.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, UNSUITABLE MATERIAL

15 Jan 13 DSC6133Progress of infilling of NE lake with unsuitable material.

26 Jan 13 DSC6262At the close of measurement for payment Jan 22nd, the volume of unsuitable materials excavated from the TSF basin was ~325,000 m3, most of it placed in the NE lake.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, LCRS DRAINS

05 Jan 13 DSC6091Typical LCRS drain excavation and installation, excavated to constant depth into the floor of a flow channel with lower part of trench 1 m deep and 0.75 m wide, to be filled with F1 sand. Upper part of trench is 0.5 m deep and 2 m wide for safety in trench and for full size roller to do compacted clay capping.

12 Jan 13 DSC6148Groundwater flows from one of the 3 LCRS drains in the east side of the TSF, easily 1 litre per second.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, BRANCH DRAINS

05 Jan 13 DSC6088A branch drain in the SE corner of the TSF showing good construction details w wrapped draincoil, F1 sand screeded to required dimensions with a template and sewing of non-woven geotextile in progress, to be followed by sewing of woven, black, geotextile.

CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, COLLECTOR DRAINS

11 Jan 13 DSC6142Cross connection for 160 dia draincoil in triple collector drain on E side of flow channel FC2, spaced at 50 m on alternating sides of central draincoil.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, COLLECTOR DRAINS

12 Jan 13 DSC6147Start of F1 sand placement on triple collector drain on E side of FC2.

14 Jan 13 DSC6159Connection of a branch drain to the main collector drain along the E side of flow channel FC2.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, FLOW CHANNELS

09 Jan 13 DSC6116Flow channel EC4 in central E side of TSF shaped and rolled, ready for HDPE liner deployment.

09 Jan 13 DSC6117Flow channel FC2 under construction, looking downstream from the permanent decant tower.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, FLOW CHANNELS

09 Jan 13 DSC6118Flow channel FC1 in the western stream course, cut to grade ready for LCRS drain excavation, side slopes being cut in preparation for later soil liner construction.

23 Jan 13 DSC6225Both sides of flow channel FC2 lined for ~500 m extent downstream of decant towers with drain installation in progress, followed by HDPE lining of channel floor and extension both u/s and d/s of the liner and drain sequence.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, SOIL LINER

05 Jan 13 DSC6089Grader and water truck processing in situ soil liner in east side of TSF basin.

11 Jan 13 DSC6139Start of soil liner construction on W side of western stream course, being done to a temporary upper limit at RL172 to allow a soil liner and general fill borrow to be developed in the SW corner of the TSF.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, SOIL LINER

25 Jan 13 DSC6237Soil liner construction advancing upstream in the western flow channel.

25 Jan 13 DSC6238The SW borrow area provided laterite for soil liner in the valley bottoms in January.


CONSTRUCTION OF THE TAILINGS STORAGE FACILITY, HDPE LINER DEPLOYMENT

04 Dec12 DSC6000Record day’s production for HDPE liner deployment of 16 rolls of liner, ~17,600 m2, on soil liner area SL100 in central E side of TSF basin.

05 Dec 12 DSC6012Status of liner deployment on W side of TSF basin, large gap in W stream course. Note also the outline of the abutments of the dividing embankment, both to be raised to stage 1 crest height, in progress.



09 Dec 12 DSC6034Lower east side of TSF coated in mud after drainage overnight of runoff from 60 mm rain event. Note high water mark on sand piles and also the steps remaining in the SE borrow area, graded off prior to the Christmas break.

04 Jan 13 DSC6087Start of liner deployment in the New Year on soil liner area SL98 on the slopes of the former SE borrow area. The graders are working on SL100 further north along the slope. Liner deployment averaged 9 rolls, ~9900 m2, per day for the 12 working days from Jan 4th to Jan 17th.



16 Jan 13 DSC6172Liner deployment advance in east side of TSF to Jan 15th.

16 Jan 13 DSC6171Liner deployment Jan 16th and 17th covered all of the area shown to the left edge of the photo, including 4 branch drains constructed concurrently with liner deployment.



25 Jan 13 DSC6236Status of liner deployment in the eastern half of the TSF at the start of the January payday weekend. Lining of the flow channel floors is awaiting placement of sand in the main collector drains, delayed by a shortage of sand at the end of the week.

24 Jan 13 DSC6229Trial welds being done on strips of liner prior to start of welding each morning and afternoon to confirm correct settings of welding machines. Coupons are cut from the trial welds and pulled to failure in the yellow-legged apparatus at left to confirm film tear bond, eg failure through the liner sheet rather than the weld itself.


BACKFILLING OF PRIMARY CRUSHER VAULT

09 Jan 13 DSC6113Resumption of mine waste backfill placement against sand surround from RL204 to final level at RL214.25.

17 Jan 12 DSC6179Cement stabilised sand poured under rock breaker cantilever on N side of crusher dump pocket.


Appx A3 Construction Photos, Nov 2012-Jan 2013 compressed

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