Zastron Sandstone

Report on the ecological assessment and wetland delineation of the proposed sandstone quarry in Zastron, Free State Province. March 2018 Prepared by: Prepared for: Environmental Management Group P.O. Box 28242 Danhof 9310 1 DECLARATION OF INDEPENDENCE DPR Ecologists and Environmental Services is an independent company and has no financial, personal or other interest in the proposed project, apart from fair remuneration for work performed in the delivery of ecological services. There are no circumstances that compromise the objectivity of the study. Report Version Final 1.0 Report on the ecological assessment and wetland delineation of the proposed sandstone quarry in Zastron, Free State Province. Title Author DP van Rensburg Mar’18 (Pr.Sci.Nat) 2 Executive Summary According to Mucina & Rutherford (2006) the area consists of Zastron Moist Grassland (Gm 1). This vegetation type is currently listed as being of Least Concern (LC) under the National List of Threatened Ecosystems (Notice 1477 of 2009) (National Environmental Management Biodiversity Act, 2004) (Map 2). The vegetation type is not currently subjected to any pronounced transformation pressures. The site is listed as an Ecological Support Area 2 under the Free State Province Biodiversity Management Plan (2015) (Map 3). Although this is not a Critical Biodiversity Area it still functions in ecological support of surrounding natural areas. It is therefore not considered to have a high conservation value. The site also does not contain any rare or endangered species which could significantly increase the conservation value. One protected species were observed on the site. P, sidoides is listed as a protected species under the List of Species that area Threatened or Protected (TOPS) (National Environmental Management: Biodiversity Act, 2004 (Act No. 10 of 2004)). This is a widespread and common species but is being exploited as a medicinal plant and permits will therefore have to be obtained to remove it. The proposed sandstone quarry will be developed on the eastern outskirts of the town of Zastron, adjacent to the settlement of Matlakeng (Map 1 & 2). The site consists almost entirely of natural vegetation (Map 1). The site is currently being utilised as communal grazing and consequently the vegetation is subjected to significant overgrazing and trampling. Furthermore, the adjacent urban area also contributes to disturbance of the site. This includes notable littering, impacts such as hunting/herding dogs on the faunal population and notable degradation of the Gryskopspruit including sewage effluent into the stream. The above listed impacts have caused significant degradation of the vegetation on the site which is notably stunted. The vegetation on the site is still largely natural although significantly degraded by the current land use. Overgrazing and -browsing as a result of the site being utilised as communal grazing area has significantly degraded the vegetation structure and species composition. Furthermore, the proximity of the urban area also causes significant disturbance of the site. This is evident in large amounts of littering and rubbish dumping on the site. The proposed mining of the site is therefore not anticipated to have a high impact. However, several unique and sensitive habitats occur around the site. A small cliff and associated seasonal pools occur adjacent and to the south of the site (Map 1). They are susceptible to erosion and form unique habitats. They are however excluded from the mining area and will not be affected as long as mining activities are kept within the site boundary. The Gryskopspruit, a highly sensitive watercourse, occurs approximately 100 meters to the south of the site (Map 1). It is also unlikely to be affected as long as a 100 meter buffer is kept from this watercourse. In addition, the preservation of the above mentioned sensitive areas around the site is dependent on adequate storm water management which should include diverting storm water around the site, separation of clean and dirty storm water, erosion control and berms and cut-off trenches along the mining boundaries. Obligate wetland vegetation was utilised to determine the presence as well as the border of wetland conditions along the Gryskopspruit as well as surrounding areas. Soil samples indicate the absence of wetland conditions on the site as well as the surrounding slopes. The soil samples taken along the Gryskopspruit, although not very distinct, does have clear indications of the presence of wetland conditions. These conditions are however clearly confined to the main channel and adjacent marginal and lower zones. Several obligate wetland species also 3 occur along the stream banks. This means that these species are confined to wetlands and cannot occur in conditions outside of these systems. As a result, where they occur, wetland conditions can be considered to occur. The Gryskopspruit occurring to the south of the site can be categorised as a channel wetland system (SANBI 2009). The Gryskopspruit to the south of the site is affected by several impacts. The most significant impacts on the stream will be the release of treated effluent from the adjacent WWTW as well as inflow of untreated sewage from the adjacent urban area. The described impacts will undoubtedly have a significant impact on the stream and it is therefore considered unlikely to have a PES of Category B: Largely Natural, at least in this section of the stream. Despite the somewhat degraded condition of the stream near the site it must still be regarded as being highly sensitive. Not least as a result of its important function in terms of water transportation but also as it is listed as a National Freshwater Ecosystems Priority Area (NFEPA). However, the site will not be located closer than 100 meters to the stream and as long as this buffer is maintained the impact should remain negligible. In addition, the mining operation should implement adequate storm water management which should include diverting storm water around the site, separation of clean and dirty storm water, erosion control and berms and cut- off trenches along the mining boundaries. The site is situated on a low plateau with moderate slopes and a small cliff surrounding it. Furthermore, a large erosion gulley is present along the southern border of the site. The above should indicate the high erosion potential that the site and proposed mining will result in. Unmitigated, it is clear that the mining activities will result in extensive erosion. However, this can be easily mitigated with standard mining procedures. Firstly, the mining site will be confined to the plateau and will not include the small cliff and associated moderate slopes which will considerably reduce the erosion potential. Secondly, standard storm water measures for small scale mining should be implemented and should significantly reduce the erosion potential. These should include diverting storm water around the site, separation of clean and dirty storm water, erosion control and berms and cut-off trenches along the mining boundaries. The impact significance has been determined and has indicated that before mitigation impacts will be mostly moderate with erosion having a potentially moderate-high impact. However, adequate mitigation will decrease impacts considerably to mostly low-moderate. 4 Table of contents Ecological assessment and wetland delineation. Declaration of Independence Executive Summary 1. Introduction 6 1.1 Background 1.2 The value of biodiversity 2. Scope and limitations 8 2.1 Vegetation 2.2 Fauna 2.2 Watercourses 2.3 Limitations 3. Methodology 10 3.1 Desktop study 3.2 Survey 3.3 Criteria used to assess sites 3.4 Biodiversity sensitivity rating (BSR) 4. Ecological overview of the site 14 4.1 Overview of ecology and vegetation types 4.2 Overview of fauna 4.3 Wetland delineation 4.4 Buffer zone determination 5. Anticipated impacts 21 6. Site specific results 23 7. Biodiversity sensitivity rating (BSR) interpretation 25 8. Discussion and conclusions 26 9. Recommendations 29 10. References 31 Annexure A: Maps and Site photos 34 Annexure B: Species list 42 Annexure C: Likely invader weed species 44 Annexure D: Soil samples 46 Annexure F: Impact methodology 49 5 Ecological assessment and wetland delineation. 1. INTRODUCTION 1.1 Background Natural vegetation is an important component of ecosystems. Some of the vegetation units in a region can be more sensitive than others, usually as a result of a variety of environmental factors and species composition. These units are often associated with water bodies, water transferring bodies or moisture sinks. These systems are always connected to each other through a complex pattern. Degradation of a link in this larger system, e.g. tributary, pan, wetland, usually leads to the degradation of the larger system. Therefore, degradation of such a water related system should be prevented. Though vegetation may seem to be uniform and low in diversity it may still contain species that are rare and endangered. The occurrence of such a species may render the development unviable. Should such a species be encountered the development should be moved to another location or cease altogether. South Africa has a large amount of endemic species and in terms of plant diversity ranks third in the world. This has the result that many of the species are rare, highly localised and consequently endangered. It is our duty to protect our diverse natural resources. South Africa’s water resources have become a major concern in recent times. As a water scarce country, we need to manage our water resources sustainably in order to maintain a viable resource for the community as well as to preserve the biodiversity of the system. Thus, it should be clear that we need to protect our water resources so that we may be able to utilise this renewable resource sustainably. Areas that are regarded as crucial to maintain healthy water resources include wetlands, streams as well as the overall catchment of a river system.

Load more