Sibanye Stillwater : Environmental incidents 2020

O U R M I N I N G I M P R OV E S L I V E S
JSE: SSW	NYSE: SBSW

LEVEL 3 ENVIRONMENTAL INCIDENTS IN 2020

No level 4 or 5 environmental incidents occurred during 2020.

No

Incident date

Incident level Operation/site

Description

Remedial action taken

Current status

SA PGM operations

1	24 April 2020	3	Kroondal - K150	Excessive rainfall of some 100mm between 1 and 21 April 2020
			return water	caused an uncontrolled decant from the K150 return water dam.
			dam	This incident was exacerbated by plant-related stoppages due to
				COVID-19.

No negative environmental consequences were observed.

• Plant operations were resumed to reduce water flow to the return Incident closed on 11 June 2020 water dam via the tailings storage facilities

• The return water dam was desilted and reeds were removed to increase storage capacity

2	24 April 2020	3	Rustenburg	An excessive rainfall event that occurred between
			- UG2	1 and 21 April 2020 caused an uncontrolled decant of some
			concentrator	30,000kl from the Klipgat return water dam. This incident was
				exacerbated by plant-related stoppages due to COVID-19.

No negative environmental consequences were observed.

• Plant operations were resumed to reduce water to the return water dam via the tailings storage facilities
• The return water dam to be desilted and reeds were removed to increase storage capacity

Desilting and reed removal to be completed by mid-2021

SA gold operations

3	3 July 2020	3	Kloof	Failure of the Leeudoorn tailings storage facility slurry pipeline	• The spilled tailings was contained and cleaned up	The incident was closed on
				due to the substandard welding of the pipe at the flange. Some	• Improved quality checks on the pipelines	21 October 2020
				1,179m3 of tailings spilt via a stormwater canal to the Loopspruit	• Increased security patrols on the pipeline route
				causing some tailings material to enter the water course. It was,
				however, a short-term spill lasting two hours.
				No negative environmental impacts were observed.
4	3 September 2020	3	Rand Uranium	Sabotage of the Cooke Plant slurry pipeline by illegal miners caused	• Clearance of the spillage on the road	The incident was closed on
			surface operation	Dump 20 to fail. The failure resulted in some 1,159m3 of tailings	• Containment of spilt slurry into the soil with	25 September 2020
				spilling next to the pipeline and onto a road. However, no tailings	constructed berms
				material entered the water course.
				• Cleaning of contained slurry when dried
				It was a short-term spill of a few hours. No negative environmental	• Increase of security patrols on the pipeline route
				impact was observed.

No	Incident date	Incident level	Operation/site	Description
US PGM operations
5	23 November 2020	3	Stillwater	High winds resulted in wind-blown tailings that exceeded air permit
				standard of 20% opacity at Hertzler tailings facility. This was a self-
				reported violation to Air Quality Bureau.

Remedial action taken	Current status
• Additional mine water was added in an effort to submerse	Closed - 30 November 2020
tailings, as an interim measure

• Magnesium chloride solution was applied as dust suppressant to exposed tailings
• Weekly opacity readings conducted to show corrective action effectiveness
• Ongoing weekly monitoring to monitor the need for additional magnesium chloride application

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O U R M I N I N G I M P R OV E S L I V E S
JSE: SSW	NYSE: SBSW

LEVEL 3 ENVIRONMENTAL INCIDENTS IN 2020 CONTINUED

An update on the 2019 level 3 incidents reported that were not closed during the previous reporting period:

Date	Place	Description and remedial action
SA PGM operations
13 November 2019	Marikana	On 13 November 2019 the Rowland corner dam discharged into a tributary of the Klein Blesbokspruit for some 36 hours.
		This unplanned discharge incident impacted clean surface water and ground water. The incident was reported to the relevant
		regulatory authority.

Subsequent detailed root cause analysis identified the inadequate flexibility to transfer the water to other operations as the main deficiency.

Actions taken included stopping the plant feeding the Rowland corner dam to reduce the water volumes to the corner dam.

Progress/Status update

• Additional mine water was added in an effort to submerse tailings, as an interim measure
• Magnesium chloride solution was applied as dust suppressant to exposed tailings
• Weekly capacity readings conducted to show corrective action effectiveness
• Ongoing weekly monitoring to monitor the need for additional magnesium chloride application

11 December 2019 Rustenburg During an environmental inspection, Naude dam at Thembelani 1 shaft was found overflowing into the natural environment. The overflow occurred for approximately three days, and the volume was estimated to be some 5,000m3. Water samples for water quality analysis were taken.

Subsequent detailed root cause analysis identified deficiencies:

• Heavy rainfall
• Accumulation of upstream flows (first flush)
• Klipfontein diversion was not closed
• Dam wall at the Naude dam is damaged

Actions:

• Proceed with the Section 21(c) and river crossing stabilisation project
• Identify and implement proper measures to ensure the effective operation of the Klipfonteinspruit diversion around the Naudé Dam
• Remove litter from the watercourse

Sibanye-Stillwater plans to implement adequate measures to effectively divert the Klipfonteinspruit around the Naudé dam after all authorisations are in place. Due to the time it could take to obtain the necessary authorisations, the Department of Water and Sanitation (DWS) should be requested to give a 'directive' to implement measures in the interim, awaiting the authorisations.

A process to repair the Naude dam is underway

For more information on our actions to minimise our environmental impact, please refer to the full 2020 Integrated report available at https://www.sibanyestillwater.com/news-investors/reports/annual.

OUR VISION: Superior value creation for all our stakeholders through the responsible mining of our mineral resources

FOR MORE INFORMATION, CONTACT:

James Wellsted	Email:	[e-mail]
Senior Vice President: Investor Relations	Website: www.sibanyestillwater.com

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