Appendix D – Specialist Studies Appendix D1 – Terrestrial Ecological Assessment Report PROPOSED DUVHA ASH DAM SEEPAGE INTERCEPTION DRAINS Terrestrial Ecological Assessment Report July 2017 Prepared for: Eskom Holdings SOC Ltd MONTH YEAR i TERRESTRIAL ECOLOGICAL ASSESSMENT REPORT PROPOSED DUVHA ASH DAM SEEPAGE INTERCEPTION DRAINS Title and Approval Page Project Name: Proposed Duvha Ash Dam Seepage Interception Drains Report Title: Terrestrial Ecological Assessment Report Authority Reference: N/A Report Status: Draft Applicant: Eskom Holdings SOC Ltd Prepared By: Nemai Consulting +27 11 781 1730 147 Bram Fischer Drive, +27 11 781 1730 FERNDALE, 2194 [email protected] PO Box 1673, SUNNINGHILL, www.nemai.co.za 2157 Report Reference: 10628 R-PRO-REP|20150514 Authorisation Name Signature Date Avhafarei Ronald Author: 15/05/2017 Phamphe Reviewed By: Lauren Robson 02/06/2017 Professional Natural Scientist: South African Ecological Science Council for Natural Scientific Professions (400349/2) Professional Member of South African Institute of Ecologists and Author’s affiliations Environmental Scientists Professional Member: South African Association of Botanists. This Document is Confidential Intellectual Property of Nemai Consulting C.C. © copyright and all other rights reserved by Nemai Consulting C.C. This document may only be used for its intended purpose JULY 2017 Pg i TERRESTRIAL ECOLOGICAL ASSESSMENT REPORT PROPOSED DUVHA ASH DAM SEEPAGE INTERCEPTION DRAINS Executive Summary Eskom Holdings SOC (Ltd) has appointed Nemai Consulting as an Independent Environmental Assessment Practitioner to conduct an Environmental Authorisation Process for the proposed Duvha ash dam seepage interception drains. The ash dam, which receives wet ash from the Duvha Power Station, is contaminating groundwater and potentially the Witbank Dam due to seepage. Seepage interception drains have been proposed to mitigate seepage and prevent contamination of the Witbank Dam. A Terrestrial Ecological Assessment was undertaken as part of the Basic Assessment process in order to assess the impacts that the proposed construction activities will have on the receiving environment. The objective of this study was to identify sensitive species and their habitats on the four proposed sites. The current ecological status and conservation priority of vegetation on the four sites were assessed. Potential faunal habitats were investigated on each site and all mammals, birds, reptiles and amphibians known to occur on site or observed on site were recorded. Red Data species (both fauna and flora) that are known to occur on site were also inspected. The four proposed ash dam seepage interception drain sites fall within the grassland biome and have been categorised as Eastern Highveld Grassland and Rand Highveld Grassland vegetation units, of which both are listed as endangered. The Grassland biome has a high biodiversity, ranked only below the Fynbos biome in terms of biodiversity in South Africa. It is found mainly on the high central plateau of South Africa, and the inland areas of KwaZulu- Natal and the Eastern Cape. Grasslands are dominated by a single layer of grasses. Trees are absent, except in a few localised habitats and geophytes are often abundant. According to the data from South African National Biodiversity Institute (SANBI), Eastern Highveld Grassland and Rand Highveld Grassland threatened terrestrial ecosystems were recorded on the proposed sites and these ecosystem types have a vulnerable status. Even though the vegetation types and threatened ecosystems are listed as endangered and vulnerable respectively, the proposed sites have been highly transformed and disturbed due to ash dams, alien plant infestation and mining activities. According to the Mpumalanga Biodiversity Conservation Plan, the proposed development sites fall within the “CBA Optimal”, “Heavily modified” and “Moderately modified- Old lands”. JULY 2017 Pg ii TERRESTRIAL ECOLOGICAL ASSESSMENT REPORT PROPOSED DUVHA ASH DAM SEEPAGE INTERCEPTION DRAINS During the field survey, no threatened species were observed on sites but only one plant species of conservation concern was noted, namely Hypoxis hemerocallidea (Star flower/African potato) and this species is listed as Declining. It is therefore recommended that prior to construction, this species must be rescued and relocated to a safer place with suitable survival and growth-enabling conditions. Following construction activities, the species can be re-established at the sites. During the field assessment, mammal species diversity was very low and this could be attributed to anthropogenic disturbances observed on sites such as habitat transformation and mining activities. Only seven mammal species were recorded on sites during the field assessment. The species recorded have a wide distribution range. Mammals are sensitive to disturbances and as such few were expected to occur on sites. No Red Data mammal species were recorded on site. The proposed development sites will have an insignificant impact on mammal conservation in the region. Species such as Blesbok were recorded in abundance on site. Conservation and planning tools were reviewed for relevancy in terms of the project area, and it was found that the study area did not contain or form part of any Important Bird & Biodiversity areas (IBAs). The unprotected IBA closest to the study area is situated approximately 40km away, namely Amersfoort-Bethal-Carolina IBA. An avifaunal study indicated that large stands of Eucalyptus trees and grasslands should provide natural habitats for bird species, however no Red Data bird species were observed on the study sites. Previous studies conducted near the study sites indicated that Red data birds species such as Southern Bald Ibis has been recorded near the High level dam servitude. Many avifaunal species are adaptable as they are habitat generalists and can therefore accommodate a certain degree of habitat degradation and transformation. Other species are extremely habitat specific and have to rely on certain habitat units for breeding, hunting or foraging and roosting. Habitat-specific species are sensitive to environmental change, with destruction of habitat being the leading cause of species decline worldwide. Due to high levels of habitat transformation, the site offers limited suitable habitat for any larger terrestrial birds as well as certain smaller raptor species. Large areas surrounding the study sites have resulted in increased habitat modification and transformation and are all causal factors in the alteration and disappearance of reptile diversity in the area. Only one reptile species was noted on site, this being the Montane Speckled Skink (Trachylepis punctatissima). This species is found in a variety of habitats, wet and dry, from JULY 2017 Pg iii TERRESTRIAL ECOLOGICAL ASSESSMENT REPORT PROPOSED DUVHA ASH DAM SEEPAGE INTERCEPTION DRAINS grassland and savanna to shrubland, including rock outcrops. It is not considered to be of significant importance from a conservation perspective. The non-perennial river on the proposed Low level dam servitude site holds water on a temporary basis and is likely an important breeding habitat for most of the frog species which occur in the region. During the field assessment, only one frog species was recorded, namely Queckett's River Frog (Amietia quecketti). It is a common species found on the banks of slow- flowing streams or other permanent bodies of water in a wide range of wetland habitats in grassland, savannah and forest fringe. It frequently inhabits garden ponds and water features. From a broad and preliminary evaluation of the study sites, it is evident that the proposed development will have minimal impacts on the receiving environment. The study sites are not unique and do not contain any rare habitats or species, and therefote it is unlikely that any species that potentially occurs will experience a large or disproportionate negative impact as a direct result of the proposed construction of seepage interception drains. The proposed development should proceed subject to the above, and mitigation measures must be employed to minimise potential impacts from the project activities. JULY 2017 Pg iv TERRESTRIAL ECOLOGICAL ASSESSMENT REPORT PROPOSED DUVHA ASH DAM SEEPAGE INTERCEPTION DRAINS Contents 1 BACKGROUND AND INTRODUCTION ________________________ 1 1.1 Objectives of the survey 1 2 RELEVANT LEGISLATION AND GUIDELINES ____________________ 2 3 STUDY AREA ________________________________________ 2 4 MPUMALANGA BIODIVERSITY SECTOR PLAN-TERRESTRIAL CRITICAL BIODIVERSITY AREAS ____________________________ 6 5 LIMITATIONS AND GAPS ________________________________ 8 6 REGIONAL VEGETATION ________________________________ 8 6.1 Eastern Highveld Grassland 10 6.2 Rand Highveld Grassland 10 7 TERRESTRIAL THREATENED ECOSYSTEMS ____________________ 11 8 METHODOLOGY _____________________________________ 13 8.1 Flora 13 8.2 Mammals 15 8.3 Avifauna 15 8.4 Reptiles 15 8.5 Amphibians 16 9 RESULTS AND DISCUSSION______________________________ 16 9.1 Flora 16 9.1.1 Desktop study results _____________________________________________ 16 9.1.2 Plant species recorded in the four proposed ash dam seepage interception drains sites _____________________________________________________ 18 9.1.3 Alien invasive species recorded in the proposed development sites _________ 20 9.1.4 Threatened Species and Species of Conservation Concern and medicinal plants recorded in the proposed development sites______________________