The first of four boreholes drilled in the Jonkershoek Nature Reserve right next to the Eerste River two weeks ago (Water at what price?, Bolander February 7), is to be capped and permanently sealed after the borehole casing fractured and vented a significant quantity of drilling sludge onto the drilling site and into the Eerste River.
The decision to permanently cap and seal the borehole came about after CapeNature, which has environmental jurisdiction over the land, was notified of the spill by the environmental control officer for the programme on Wednesday January 31.
In a subsequent media statement to Bolander, CapeNature spokesperson Marietjie Engelbrecht said: “Upon inspection it was observed that a considerable plume of sediment had been washed into the Eerste River. This was apparently caused by a failure of the borehole casing and the drilling equipment. No containment structures were in place to contain the spill.
“The borehole had stopped spilling water and sediment by Thursday February 1. Monitoring of the site is required to assess impacts, particularly to the river.
“On Saturday February 3, a River Health: South African Scoring System (SASS) and water quality assessment was done and results so far indicate some immediate impact in terms of the invertebrates in the Eerste River. CapeNature scientists will be going back to the three sites to collect the physico-chemical variables (temperature, conductivity, dissolved oxygen and pH) data.
“CapeNature observed that clean-up operations at the drill site commenced over the weekend. CapeNature expects and trusts that the borehole will be permanently capped and that this site will be promptly and effectively rehabilitated, both the effects on the river and the sediment accumulation around the borehole site.
“Follow up inspections will be conducted by CapeNature scientists to continue to monitor the impact on the river health.”
The boreholes are being sunk as part of the Stellenbosch Municipality’s groundwater exploration drilling programme as part of its drought response plan to augment Stellenbosch’s water supply.
According to an annotated map in the site specific method statement, prepared in terms of the environmental management plan (EMP) for the drilling programme, the remaining three boreholes will be drilled in the vicinity of the Sirkel Pad south-east and north-west of the first drilling site, but not adjacent to the Eerste River.
In response to a detailed list of questions Bolander submitted to the Stellenbosch Municipality about its drilling programme, municipal manager Geraldine Mettler said: “The sinking of boreholes is part of the Stellenbosch Municipality’s drought management plan. We follow all prescribed processes required by legislation.
“The final number of boreholes will be determined by the yield of the boreholes. The locations are spread over the WC024 area according to the position of the water demand.”
According to Ms Mettler, the Department of Environmental Affairs and Development Planning (DEADP) issued a directive in terms of Section 30A (Emergency Situations) of the National Environmental Management Act, No. 107 of 1998, which exempts the municipality from obtaining an environmental authorisation, and hence the need to undertake environmental impact assessments in respect of its exploratory drilling programme.
She added that an environmental specialist and an environmental control officer had been appointed to assist in minimising potential impacts pertaining to groundwater development.
Although an environmental authorisation is not required, according to CapeNature a signed environmental management plan (EMP) for each site is still required.
In her media statement, Ms Engelbrecht added: “The siting of the boreholes and the manner in which they and their associated infrastructure are constructed must be done with due consideration of ecological impacts, as these are placed in sensitive ecosystems.
“This includes siting the boreholes away from populations of threatened species, threatened habitats and sensitive ecosystems.
“All efforts must be made to firstly avoid any onsite damage to the ecosystem and mitigate any unavoidable impacts. This includes taking all reasonable proactive measures to minimise impact footprint and avoid and contain any spillages from the borehole or associated equipment.
“In the case of any accidental spills or other damage the contractors are expected to remedy the situation by prompt and effective rehabilitation.
“CapeNature is most concerned at the recent reports of drill sites where there have been failures to employ sufficient duty of care and calls for much more rigour, proactive planning, communication and professional execution of drilling operations.”
In response to Bolander’s question about why no attenuation dam was built to contain spills, Ms Mettler responded: “The (site specific) method statement does not make provision for an attenuation dam for such an emergency situation, since the possibility of such an incident occurring, according to the drilling contractors, is low. The impact associated with clearing of natural vegetation to construct an attenuation dam, specifically in Jonkershoek, would have been very significant and not justifiable.”
In response to a follow-up enquiry, CapeNature’s Ms Engelbrecht said: “CapeNature was involved with site visits and discussions prior to the drilling at Jonkershoek and provided a list of key issues that need to be addressed, that could potentially limit environmental impact on the site.
“Today, Friday February 9, CapeNature and the Stellenbosch Municipality had a productive meeting where it was agreed that we will work together to rehabilitate and mitigate impacts that occurred at this specific site and work much closer together to mitigate against other environmental impacts that accompany water augmentation activities.”
On the question of licensing, Ms Mettler pointed out that a licence is not required from the Department of Water and Sanitation (DWS) to drill a borehole, but that dependent upon the final volume of water abstracted, a licence may be required, but that DWS has granted a two-year period to acquire such licences.
Jonkershoek resident Andrew Hagen, who with his wife, Hayley, first drew Bolander’s attention to the drilling operations next to the Eerste River and the subsequent sludge spill, visited the area on Thursday evening and took photographs to determine the extent of cleaning up and rehabilitation.
“Cleaning up of the drilling site has proceeded and the river water downstream is much cleaner than it was, probably due to natural settling out of the sediment, but nothing has yet been done to remove the sludge from the river bed,” said Mr Hagen.
Bolander will be submitting follow-up questions to Stellenbosch Municipality to establish when the clean-up and rehabilitation work of the sludge spill will be completed.