Experts want probe into Mwadui plant by independent body

Dar es Salaam. Experts have advised the commissioning of the Independent Tailings Review Board (ITRB) as a compliance to the international standard on tailings management in the wake of Williamson Diamond’s Tailings Storage Facility (TSF) problems. ITRB is necessary for TSF under the Global Industry Standard on Tailings Management (GISTM), as it will identify and evaluate engineering and decision-related reasons that contributed to the failure.
Ms Lindsay Bowker, an executive director for the US-based watchdog World Mine Tailings Failures (WMTF), stated that the review committee needs to look closely at the choices and engineering that led to the failure condition.
“The Williamson’s TSF failure comes months after the firm had expanded its operations, thus the government and Petra should have commissioned one (ITRB),” she said.
According to her, there has been no reduction in tailings dam failures recorded over the past two decades, and that the Mwadui incident is the 19th catastrophic tailings failure since 2015 with only 18 predicted on an actuarial basis.
“WMTF has classified this Mwadui incident as ‘very serious’ (catastrophic), in fact, Tanzania has four TSFs, all at diamond mines listed in the CoE disclosures, all rated High Hazard potential,” she noted. The CoE disclosures, refers to when the Church of England (CoE) on behalf of 112 investors, representing $14 trillion in assets under management, wrote to the Board Chairs and CEOs of listed extractive companies and requested specific disclosure on tailings facilities.
“To our knowledge neither Petra, who just boasted their commitment to the Global Standards nor the government who owns 37 percent of the facility, have commissioned an independent cause of failure analysis,” she explained.
According to her, the commissioning of ITRB would reflect on the range of issues relevant to the facility, and its context and the complexity of the matter, including providing independent technical review of the design, construction, operation, closure, and management of the tailings facility.
It is said that ITRB members are third parties who are not, and have not been, directly involved with the design or operation of the particular tailings facility. Moreover, information available at Petra Diamonds shows that the company is committed to implementing the GISTM as of June this year, its board of directors approved and adopted a tailings Management Policy.
“The Williamson diamond mine in Tanzania does not require a COP by law, but since 2016, in line with best practice Petra developed and implemented operating practices, set out in an operating manual, similar to a COP for the mine’s tailings deposits,” the company’s tailings management disclosure reads  partly.
COP includes and refers to the design, management instructions, recommended standards and procedures required to manage and monitor the operation of the facilities. The business asserts that there are two Fine Residue Deposits (FRDs), one of which is operational, at the Williamson mine in Shinyanga.
For his part, Eng Peter Kaheshi, currently pursuing a doctorate related to Tailing Dams and Mine wastes management in Canada, said: “This is inevitable, the company need to clean as well as assess the stability of its TSF and implement technical interventions deemed necessary to avoid such undesired events in future.”
Adding: “This shouldn’t be taken rightly regardless of minimal effects it may have caused; rather, it should be seen as a wakeup call to mining operators and government by assessing geotechnical aspects for the existing TSFs for possible monitoring measures.