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Spencer Harrison
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1 C R LUBBE 6 Athlone Street Tel: SWELLENDAM Cell: macquarrie@vodamail.co.za Attention: Louise Mari van Zyl Cape EA Prac 1 June 2018 P O Box 2070 GEORGE 6530 Dear Ms van Zyl AGRICULTURAL IMPACT STATEMENT FOR THE AGRICULTURAL SOLAR POWERED DESALINATION PLANT NEAR WITSAND The Hessequa Municipality received an S30A Emergency Directive from the Department of Environmental Affairs to implement various water supply projects as part of the drought disaster scheme for the Western Cape. The Municipality is planning to construct a small desalination plant at one of their existing abstraction points on the Breede River. This plant will have a product capacity of 300kl/day. The plant will be erected within the existing fenced municipal water supply area and the solar plant will be erected next to it. The total area for the desalination plant and solar plant will not exceed 900 square meters. The solar plant will take up ±500 square meters and the desalination plant with associated intake and discharge infrastructure the remainder. The main focus of this study is to identity potential agricultural impacts and provide details on the mitigation measures and management requirements that should be implemented. Physical description of site Locality: The site is situated on the farm Rhenosterfontein Estate, Portion 1 and accessible from the R324 near Witsand. Permission for entry can be obtained from Mr A Gunter cell no

Figure 1: Locality Access to the site from the R324 is with a dirt road. The road is well maintained.

required. Figure 2: Access road and site photos The existing pump house is fenced and located in the corner of the cultivated land.

The reason is that the slope does not require such structures but mainly because No-Till planting is executed on the land.

2 Figure 1: Locality Access to the site from the R324 is with a dirt road. The road is well maintained. Depending on the bulk size of material and equipment that will be used during the construction phase of the project, an alternative road may be required. Figure 2: Access road and site photos The existing pump house is fenced and located in the corner of the cultivated land. There is no contour banks on the land. The reason is that the slope does not require such structures but mainly because No-Till planting is executed on the land. The planters are fitted with knife edge point openers and press wheels. Cultivation takes place simultaneously with the planting process but less than 20% of the soil is disturbed. Topography The topography is level plains with some relief. Traveling along the R324, the topography is perceived as continuous rolling land with grain lands and grazing fields. 2

3 Vegetation According to Acocks, the vegetation expected is Temperate and Transitional Forest and shrubs. The vegetation type is Fynbos and Renosterveld. Vegetation is an indicator of the climate and soil potential of the region. Fynbos is confined to an area with poor soils with low quantities of phosphorus and nitrogen. Renosterveld grows in more nutrient rich soils formed on Shale parent material. The site lies on the transition between the Limestone Fynbos Districts of Bredasdorp and Mossel Bay and Eastern Rûens Shale Renosterveld. Therefore, the soil characteristics may be either of the two. Climate The site is in the winter rain fall area where winter grain is produced. Temperatures are the lowest during this season, meaning the lowest evapotranspiration takes place. Although the quantity of rain is low, the quality (distribution over time) effects the yield of the crop. Soils Figure 3: Witsand temperatures (Source: Google) The land type map 3420 Riversdale of the Department of Agriculture and its inventory was used in the desktop study for this project. A copy of the landtype map appears in Figure 4. 3

Figure 4: Land Type map 3420 Riversdale According to the Land type map, the soils in the region will fall in the Fa - Fc group. Soils in these groups accommodate pedologically young landscapes.

4 Figure 4: Land Type map 3420 Riversdale According to the Land type map, the soils in the region will fall in the Fa - Fc group. Soils in these groups accommodate pedologically young landscapes. Soil forming processes have been rock weathering, the forming of orthic horizons (top soil) and the subsoil with clay illuviation into weathering rock (Lithocutanic Horizon). The pedological form for a soil with such a profile is Glenrosa. The soil forming process did not advance to the lithocutanic stage and the top soil is on hard rock (Mispah). The site specifically, falls in the Fc27 group. This means that 40% will be Glenrosa, 20% Mispah, 20% Swartland and 20% coarse deposits can be expected. With the field visit this prediction was confirmed. The site was visited on 16 May Figure 5 shows the location of the observation points and the soil characteristics of these points are set out in Table 1. The soil survey was done on a random basis. This means that features such as changes in vegetation and topography were used as observation points. 4

Figure 5: Soil survey observation points Table 1: Soil field observations Glenrosa InverdoornOBS: 24 & 22 OBS 24 COMMENT: LAT 34.40166 SLOPE GRAD 1 LONG 20.

5YR5/6 30 f 3 wb 40 TERR_POS 1 LTN so PHOTO y 3 C 1200 L.

5 Figure 5: Soil survey observation points Table 1: Soil field observations Glenrosa InverdoornOBS: 24 & 22 OBS 24 COMMENT: LAT SLOPE GRAD 1 LONG SLOPE SHAPE FORM Gs TSD 40 WET 0 HOR TYPE DEPTH COL CLAY S-GR CONS STRUC STONE FAM 2112 ESD 30 C l 1 A YR4/4 15 f 4 wc 40 ROUGH 1 ASD GEO S1 2 B YR5/6 30 f 3 wb 40 TERR_POS 1 LTN so PHOTO y 3 C 1200 L.COVER/USE: Cultivated 4 R MOISTURE EROSION L L Soil Properties A Horizon Topsoil B Horizon Sub-soil C-Horizon Sub-strata Texture fine loam sand fine sand clay loam Consistency Crumbly to very crumbly Slightly solid and hard Saprolite Structure Weak crumbly Weak blocky Colour Brown (W) Strong brown (W) Horizon Depth 300mm 500mm >500mm 5

Depth limitation Saprolite Effective Depth 300 Terrain position Crestline Geology Shale Slope shape Strait Slope gradient 2% Moisture availability Low Erosion potential Low Soil Form Glenrosa Soil

78791 SLOPE SHAPE R EROSION L FORM Ms TSD 30 WET 0 HOR TYPE DEPTH COL CLAY S-GR CONS STRUC STONE FAM 2200 ESD 30 C l 1 A 30 7.

6 Depth limitation Saprolite Effective Depth 300 Terrain position Crestline Geology Shale Slope shape Strait Slope gradient 2% Moisture availability Low Erosion potential Low Soil Form Glenrosa Soil Family Inverdoorn Mispah Steinkopf &26 OBS 23 COMMENT: LAT SLOPE GRAD 1 MOISTURE L LONG SLOPE SHAPE R EROSION L FORM Ms TSD 30 WET 0 HOR TYPE DEPTH COL CLAY S-GR CONS STRUC STONE FAM 2200 ESD 30 C l 1 A YR4/4 15 f 4 wc 40 ROUGH 1 ASD GEO S1 2 C 1200 TERR_POS 1 LTN rr PHOTO y 3 L.COVER/USE: Cultivated 4 Soil Properties Texture Consistency Structure Colour A Horizon Topsoil fine loam sand Crumbly to very crumbly Weak crumbly Brown (W) C-Horizon Sub-strata Horizon Depth 300mm >300mm Depth limitation Hard rock Shale Effective Depth 300 Terrain position Midslope Geology Shale Slope shape Convex Slope gradient 5% Moisture availability Low Erosion potential Medium Soil Form Mispah Soil Family Steinkopf Rock 6

7 INFLUENCE OF THE PROPOSED DEVELOPMENT ON THE AGRICULTURAL ENVIRONMENT When land is assessed for its agricultural potential, all soil physical properties and climatic conditions are considered to determine its inherent ability to give a certain yield within the limits of its soil properties and climatic conditions. From Figure 6, it is clear that soil on site has restrictive physical properties. 0 Loam sand ( 15% clay) Water holding capacity : 127 mm/m Plant available 300mm =38mm Soil volume available 50 % Effective root depth 300mm 500mm Sand clay (40% clay) Water holding capacity : 177mm/m Plant available 250 mm=35.4mm Soil volume available 50% Limiting layers Weathered rock Figure 6: Soil Profile Any plant needs three basic elements to grow successfully, namely air, moisture and nutrients. Normally, a 1.2m deep soil profile is adequate to provide the required air and moisture for growth, with plant nutrition added as required. However, some layers in the soil prevent plant root development. These include wetness, stone layers, compaction, abrupt change in soil texture or structure, as in this case. The nearer to the top this restrictive layer occurs, the more negative the effect on the plant. To calculate the possible yield, climatic information plays an important role. The following sources were used: ARC Small Grain Institute for production of small grain in the Eastern Rûens ( 2014 Report). Rainfall data from local reports of the South African Weather Service for the farm Rolhoek, Witsand (Doc 4137). Crop factors and Evaporation values from the Irrigation design manual of the ARC. The methodology followed was to calculate what the water requirement for production through the growing season was and test the yield obtained against the precipitation during the growing stages. Table 2: Rainfall figures and yield Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual Yield t/h Et/mth Crop factor Allowable loss of evaporation

8 Table 2 shows that 2011 had the highest yield although the precipitation was the lowest. The distribution played the important role. With the unpredictable rain, a buffer is needed when moisture shortages occur. The buffer would be the soil. With a shallow soil as in this case, drought and waterlogging is possible in the same season. This places the proposed development area in Land Capability Class VI. Land in class VI has severe limitations that make it generally unsuited for cultivation and limit its use to pasture and rangeland. These limitations include the following: Stoniness Shallow rooting zone Low water holding capacity Severe climate Possible Impacts The establishment of the Solar Farm will be done at the expense of agricultural land. Impacts during construction phase Possible erosion to access road with transport of building material. Interference with cultivation operations. The placement of spoil material accumulated from excavations of foundations. Construction machinery and building materials used in the development of the solar farm may pollute the soil during the construction phase with contaminants such as spillages of hydrocarbon (fuel oil) and cement leaving an unproductive growing medium. Loss of agricultural land although it is of low significance. The total area is 0.1 ha (1000m²) Mitigation measures Maintain road and install berms to regulate the flow speed. Respect all existing conservation and agricultural practices. Maintain all structures and prevent interference with normal farming activities as far as possible. Schedule construction phase in off season (Summer). Place rubble at a temporary stockpile area, from where licenced contractors can haul it to a licenced land fill area. Rehabilitate the foundation site used for infrastructure and landscape to previous condition. Refuelling must take place in a designated area. This area must have an impervious floor with low wall that will keep the spillage inside. This area should be cleaned with absorbent material on a regular basis. When spillage accidently takes place, it should be removed and replaced with unpolluted soil. 8

9 Conclusion and Recommendation It is my considered opinion that constructing a small desalination plant and solar plant will have an insignificant influence on the agricultural activities and productivity of the farm. The land capability is generally unsuited for cultivation and limit its use to pasture and rangeland. These continuing limitations cannot be corrected because they include: Stoniness Shallow rooting zone Low water holding capacity Severe climate Furthermore, the area lost to agricultural production is only 0.1 ha. C R LUBBE 9

SOIL SURVEY FOR PROPOSED WET ASH DISPOSAL FACILITY, HENDRINA POWER STATION, MPUMALANGA PROVINCE

REPORT for Lidwala Environmental and Planning Servives by the INSTITUTE FOR SOIL CLIMATE AND WATER AGRICULTURAL RESEARCH COUNCIL SOIL SURVEY FOR PROPOSED WET ASH DISPOSAL FACILITY, HENDRINA POWER STATION,