Environmental Scoping Report for the proposed establishment of a New Coal-Fired Power Station in the Lephalale Area, Limpopo Province 6. WATER RESOURCES 6.1. Scope of Work The project aimed at assessing the surface and groundwater resources within an area of ± 245 km2 study area, based on the location of the eight candidate sites and the existing Matimba Power Station and infrastructure. The scope of work for the Environmental Scoping Study included: • A status quo study, regarding quality and quantity of water resources. • A site suitability assessment from a groundwater and surface water perspective. • An evaluation of all monitoring data, hydrochemical trend identification, and contamination assessment (coal stockyard, ash dams, etc.). • Consideration of stormwater controls. • Surface water availability and supply, • Groundwater resources. 6.2. Methodology A desktop study and limited fieldwork were undertaken in order to collate sufficient information to compile the water resources and candidate site assessments report. These data were assessed in order to address the hydrogeological and surface water aspects of the proposed project. 6.2.1. Desktop Study and Data Sources All available geological, surface water, and hydrogeological data for the study area was compiled from various sources and analysed. All relevant hydrogeological data, such as water levels, abstraction, hydrochemistry, and drilling records, was available from either Eskom or the Grootegeluk mine. The following data sources were used during the study: • du Toit, W.H., 2003. The hydrogeological map Polokwane 2326. Department of Water Affairs and Forestry • Geological Survey, 1993. 1:250 000 Geological series 2326 Ellisras geological map. • Johnstone, A. C., 1989; A hydrogeological investigation of the Grootegeluk Mine, Unpublished M.Sc thesis, Rhodes University. Water Resources 53 18/11/2005 Environmental Scoping Report for the proposed establishment of a New Coal-Fired Power Station in the Lephalale Area, Limpopo Province • Hodgson, F. and Vermeulen, D. 2004. Extension of the groundwater monitoring system at Matimba Power Station. Unpublished report no. 2004/12/FDIH, Institute for Groundwater Studies (IGS), University of the Free State • The Internal Strategic Perspective (ISP) of the Limpopo Water Management Area, Department of Water Affairs and Forestry (Ref No. P WMA 01/000/00/0101, July 200) • Roux L., 2001. Grootegeluk Coal Mine Geohydrological perspective. Unpublished report, Grootegeluk Coal Mine Geology Department • Roux L., 2003. Revised numerical groundwater modelling at Grootegeluk Coal Mine. Unpublished report, Grootegeluk Geohydrology Kumba Resources • Steenkamp, G., 2001. Numerical groundwater modelling at Grootegeluk Coal Mine. Internal report, Kumba Resources • The groundwater harvest potential of the Republic of South Africa. Department of Water Affairs and Forestry, 1996 • The groundwater resources of the Republic of South Africa, sheets 1 and 2. Water Research Commission and Department of Water Affairs and Forestry, 1995 • The national groundwater database, Department of Water Affairs and Forestry, Pretoria Discussions, regarding the geology and hydrogeology, with the Grootegeluk mine’s geologist, Mr. Leon Roux, were also conducted. 6.2.2. Fieldwork The fieldwork conducted during the study included a site visit to the power station and the Grootegeluk colliery. A visit to each of the four initial candidate sites was conducted. The scope of work was expanded to include an additional four candidate sites, however, due to the abundance of geological and hydrogeological data, no additional fieldwork was conducted. 6.3. Overview of the Geology of the Area Sediments and volcanics of the Waterberg Group and Karoo Supergroup underlie the study area. Table 6.1 presents the lithostratigraphy of the area. Water Resources 54 18/11/2005 Environmental Scoping Report for the proposed establishment of a New Coal-Fired Power Station in the Lephalale Area, Limpopo Province Table 6.1: Lithostratigraphy Age Supergroup / Formation Alternative Lithology Group Name Jurassic Karoo Letaba Letaba Formation Basalt Triassic Clarens Clarens Fine-grained Formation cream-coloured sandstone Triassic Lisbon* Elliot Formation Red mudstone and siltstone Triassic Greenwich* Molteno Red sandstone Formation and conglomerate Triassic Eendragtpan* Beaufort Group Variegated shale Permian Grootegeluk* Upper Ecca Group Mudstone, carbonaceous shale, coal Permian Goedgedacht* Middle Ecca Gritty mudstone, Group mudstone, sandstone, coal Permian Swartrant* Lower Ecca Group Sandstone, gritstone, mudstone, coal Permian / Karoo / Dwyka Wellington* Dwyka Group Mudstone, Carboniferous siltstone, minor grit Carboniferous Waterkloof* Dwyka Group Diamictite, mudstone Mokolian Waterberg Mogalakwena Mogalakwena Fm Coarse-grained purplish brown sandstone *Not yet approved by the South African Committee on Stratigraphy (SACS) A veneer of quaternary (2 Ma) sandy soil covers the Waterberg Group sediments to the south of the study area. Figure 6.1, a portion of the 1:250 000 geological map 2326 Ellisras, illustrates the study area geology. Figure 6.2 presents the structural geology within the study area, as provided by Mr. Leon Roux, Grootegeluk Coal Mine. Water Resources 55 18/11/2005 Environmental Scoping Report for the proposed establishment of a New Coal-Fired Power Station in the Lephalale Area, Limpopo Province Legend Qs Sandy soil NORTH Jl Letaba basalt Ђ c Clarens sandstone Ђ l Lisbon mud stone Ђ g Greenwich red sandstone Ђ e Een dragtpan variegated shale Pgr Grootegeluk mudstone, coal Pgo Goedgedacht gritty mudstone Ps Swartrant sandstone, coal C- Pwe Wellington mudstone Cwa Waterkloof diamictite Mm M ogalakwena sandstone f I Faults - Study area Figure No: 2 Portion of the 1:250 000 Geological Map Scale: Not to 23 26 Ellisras P.O. Box 2597 Tel.: (011) 803 -5726 Rivonia Fax.: (011) 803 -5745 2128 jhb@gcs -sa.biz Project No: 2004.11 .5 3 5 Figure 6.1: A portion of the 1:250 000 geological map 2326 Ellisras, illustrating the study area geology Water Resources 56 18/11/2005 Environmental Scoping Report for the proposed establishment of a New Coal-Fired Power Station in the Lephalale Area, Limpopo Province Figure 6.2 – Structural geology within the study area Water Resources 57 18/11/2005 g ev2qiyvyq2srsx2 h2eie PU°QH9HH4 PU°QH9QH4 PU°QI9HH4 PU°QI9QH4 PU°QP9HH4 PU°QP9QH4 PU°QQ9HH4 PU°QQ9QH4 PU°QR9HH4 PU°QR9QH4 PU°QS9HH4 PU°QS9QH4 PU°QT9HH4 PU°QT9QH4 PU°QU9HH4 PU°QU9QH4 PU°QV9HH4 PU°QV9QH4 PU°QW9HH4 PU°QW9QH4 PU°RH9HH4 PU°RH9QH4 PU°RI9HH4 PQ°QT9HH4 viqixhX PQ°QT9HH4 PQ°QT9QH4 7 fQI PQPUheHHITT eI PQPUheHHITS PQ°QT9QH4 PQPUheHHITV PQPUheHHITU 7 PQPUheHHITW 55 5 5 55 5 PQ°QU9HH4 5 PQPUheHHITR PQPUheHHITQ PQPUheHHHPT PQ°QU9HH4 PQPUheHHITP PQPUheHHITI 7 uf PQ°QU9QH4 PQPUheHHIIR 7 fV PQ°QU9QH4 fW PQPUheHHIHQ 5 7 PQPUheHHIHR PQ°QV9HH4 5 PQPUheHHIIS PQPUheHHIHS 5 PQPUheHHIIU 5 fSI PQPUheHHIUV 5 PQPUheHHIIW 7 fIH fQ 7 ev PQ°QV9HH4 7 7 PQPUheHHQSH fIT 5 fTI 7 fPR PQ°QV9QH4 7 fTP fIRI 5 PQPUheHHISP fIS 75 fIRP 7 fR 7 fU 5 PQPUheHHIHP PQ°QV9QH4 fIRQ 7 fPS 75 7 fQP yfIH 7 7 PQ°QW9HH4 fIQ 7 yfQ 77 fPV pvI PQPUheHHHHU PQPUheHHHHV fSH 7 7 5 PQPUheHHQIP IR PQ°QW9HH4 fQR fQS ³5 7 IQ 7 fQQ 7 fRV fP fQV ³5 IS vIR fQT 7 75 fRU ³5 PQ°QW9QH4 7 fRW 7 vII 7 7 7 fPS ³5 PS ³5 W 7 ³5 V vIU 7 PQ°QW9QH4 7 yfP fQI 7 U 7 vIQ fIV fQV fSI T qruPT fIWf fRQ ³5 ³5 5 vIS 7 7 fIWI 7 fRS PQ°RH9HH4 775 7 S IU 7 5 5 7 7 7 iiTH fIWP 75 fRT ³5 qruIU 75 vIT vW 7 fQH IT ³5 75 fRH R II ³5 7 7 quUW 75 5 PQ°RH9HH4 7 ³5 PT ³ 5 IH 5 7 quWQ quWS 7 7 ³5 PU quUV fPT ³5 7 ³5 ³5 IW PQ°RH9QH4 7 7 fRI 7 IV fIU fRP fQT PV ³5 ³5 quWP quUS 7 PQ°RH9QH4 7 7 quQU fQW fPPP iTT quWI quUR 7 7 quVW fW iWH 7 quWR 7 7 7 PQ°RI9HH4 7 7 7 iVW 7 qrootegeluk2oreholes2 quVS 7 rPU 7 quVU quUP quTI iUH PQ°RI9HH4 7 7 75 7 quUI rQQ 7 7 7 rPT iVV 7 7 ³5 wtim2oreholes2 7 7 7 xxII rQP xxIQ PQ°RI9QH4 rRH 7 rRT rRR xxIP 7 5 xqhf2oreholes2on2V2frms2 rRU 7 7 7 7 fQR 7 fQS PQ°RI9QH4 7 Q rRI ³5 PQ°RP9HH4 pults2derived2from2oreholes2 fQU PH fQUe I ³5 5 ³5 PP PQPUheHHHIQ 7 eeromgnetis2vinements2 PQ°RP9HH4 PQPUheHHHIW PQPUheHHHIPPQPUheHHHII PQPUheHHHIR P PI ³5 PQPUheHHIPH PQPUheHHHIS ³5 ³5 PQPUheHHHIT PQ°RP9QH4 PQPUheHHIPI PQPUheHHHIU PQPUheHHIPP PQPUheHHHIV prm2oundries2@qA2 PQPUheHHHHW 5 PQPUheHHIPQ 55 5 555 PQPUheHHHIH PQ°RP9QH4 555 55 22smge gsPQPUdIWVIFtif PQ PQ°RQ9HH4 PQPUheHHHPW ³5 PQPUheHHHQH PQ°RQ9HH4 PQPUheHHHQI 5 PQPUheHHHQP PR PQPUheHHHRP PQPUheHHHQQ ³5 PQ°RQ9QH4 PQPUheHHHRQ PQPUheHHQHI PQPUheHHHQS 5 HFS H HFS I IFS P PFS uilometers PQPUheHHHRS PQPUheHHQHP 5 PQ°RQ9QH4 PQPUheHHHRU PQPUheHHQHQ PQ°RR9HH4 55 PQ°RR9HH4 PQ°RR9QH4 x qs el2@HIIA2VHQESUPT rojetX222PHHRFIIFSQS PQ°RR9QH4 imilX2 jhdgsEsFiz wtimf PQ°RS9HH4 wwwFgsEsFiz ©2gopyright2qgF hte2rintedX2222UGTGPHHS PQ°RS9HH4 PU°QH9HH4 PU°QH9QH4 PU°QI9HH4 PU°QI9QH4 PU°QP9HH4 PU°QP9QH4 PU°QQ9HH4 PU°QQ9QH4 PU°QR9HH4 PU°QR9QH4 PU°QS9HH4 PU°QS9QH4 PU°QT9HH4 PU°QT9QH4 PU°QU9HH4 PU°QU9QH4 PU°QV9HH4 PU°QV9QH4 PU°QW9HH4 PU°QW9QH4 PU°RH9HH4 PU°RH9QH4 PU°RI9HH4 pigure2Q Environmental Scoping Report for the proposed establishment of a New Coal-Fired Power Station in the Lephalale Area, Limpopo Province 6.3.1. Structural Geology The study area falls within the Waterberg Coalfield, which comprises a graben structure with the Eenzaamheid fault forming the southern boundary and the northern boundary is delineated by the Zoetfontein fault. Archaean granite rocks outcrop to the north of the Zoetfontein fault and sediments of the Waterberg Group outcrop to the south of the Eenzaamheid fault. The study area is further subdivided by the Daarby fault, a major northeast then northwest trending fault. The Daarby fault has a down throw of 360 m to the north, at an angle of 50° to 60°.