{"id":41629,"date":"2022-09-13T07:12:00","date_gmt":"2022-09-13T07:12:00","guid":{"rendered":"https:\/\/blogs.agu.org\/landslideblog\/?p=41629"},"modified":"2022-09-13T07:12:00","modified_gmt":"2022-09-13T07:12:00","slug":"jagersfontein-tailings-dam-2","status":"publish","type":"post","link":"https:\/\/blogs.agu.org\/landslideblog\/2022\/09\/13\/jagersfontein-tailings-dam-2\/","title":{"rendered":"Analysing the aerial and satellite imagery of the Jagersfontein tailings dam disaster"},"content":{"rendered":"<h4>Analysing the aerial and satellite imagery of the Jagersfontein tailings dam disaster<\/h4>\n<p>The impacts of the <a href=\"https:\/\/blogs.agu.org\/landslideblog\/2022\/09\/12\/jagersfontein\/\">catastrophic tailings dam failure at Jagersfontein<\/a> are slowly becoming apparent.\u00a0 The plume of slimes has devastated a large area and ruined many lives.\u00a0 Yesterday, <a href=\"https:\/\/www.youtube.com\/watch?v=XNcbLhwcI8A\">aerial footage emerged of the site of the disaster<\/a>, illustrating the scale of the clean up operation that will be needed:-<\/p>\n<iframe loading=\"lazy\" title=\"WATCH | Jagersfontein flooding as seen from the air\" width=\"800\" height=\"450\" src=\"https:\/\/www.youtube.com\/embed\/XNcbLhwcI8A?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen><\/iframe>\n<p>.<\/p>\n<p>From about 52 seconds this video shows the tailings facility itself, including the breach:-<\/p>\n<div id=\"attachment_41632\" style=\"width: 810px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-41632\" class=\"wp-image-41632\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-5.jpg\" alt=\"An aerial image of the site of the Jagersfontein tailings dam failure. \" width=\"800\" height=\"389\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-5.jpg 1181w, https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-5-300x146.jpg 300w, https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-5-1024x498.jpg 1024w, https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-5-768x373.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><p id=\"caption-attachment-41632\" class=\"wp-caption-text\"><em>An aerial image of the site of the Jagersfontein tailings dam failure. <a href=\"https:\/\/www.youtube.com\/watch?v=XNcbLhwcI8A\">Still from a video posted to Youtube by News24.<\/a><\/em><\/p><\/div>\n<p>.<\/p>\n<p>The image shows that the slimes in the eastern half of the facility have mobilised and escaped, but those on the western side appear to have been mostly retained by an internal structure.\u00a0 Ensuring that these do not mobilise must be a very high priority.<\/p>\n<p>The breach itself is heavily eroded, meaning that it is difficult to determine whether the failure was caused by overtopping, piping or slope instability.\u00a0 On both side of the breach, fresh slimes are coating the walls of the tailings dam, illustrating the high mobility of the mine waste.\u00a0 Note the width of the walls of the tailings dam here &#8211; much greater than in other parts of the facility.\u00a0 I wonder why?<\/p>\n<p>Whilst the main breach is clear, there are several other locations where there appears to have been substantial erosion of the dam walls.\u00a0 The image below shows these:-<\/p>\n<div id=\"attachment_41634\" style=\"width: 810px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-41634\" class=\"wp-image-41634\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-6.jpg\" alt=\"An aerial image of the site of the Jagersfontein tailings dam failure, showing other areas of erosion. \" width=\"800\" height=\"376\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-6.jpg 1210w, https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-6-300x141.jpg 300w, https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-6-1024x482.jpg 1024w, https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-6-768x361.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><p id=\"caption-attachment-41634\" class=\"wp-caption-text\"><em>An aerial image of the site of the Jagersfontein tailings dam failure, showing other areas of erosion. <a href=\"https:\/\/www.youtube.com\/watch?v=XNcbLhwcI8A\">Still from a video posted to Youtube by News24.<\/a><\/em><\/p><\/div>\n<p>.<\/p>\n<p>One of these is to the west of the main breach, on the left side of the image above.\u00a0 This appears to threaten the stability of the remaining tailings and needs very urgent attention.\u00a0 There are two more to the east side (on the right side of the image).\u00a0 I am unsure as to how these will have formed.\u00a0 Did the tailings develop waves within the pond that overtopped at other locations?\u00a0 The investigation will need to understand these features.<\/p>\n<p>Meanwhile, on the other side of the Jagersfontein tailings facility, another slope failure has occurred:-<\/p>\n<div id=\"attachment_41636\" style=\"width: 809px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-41636\" class=\" wp-image-41636\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-7.jpg\" alt=\"An aerial image of the site of the Jagersfontein tailing dam failure, showing a possible drawdown failure on the opposite side of the facility.\" width=\"799\" height=\"554\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-7.jpg 824w, https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-7-300x208.jpg 300w, https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-7-768x532.jpg 768w\" sizes=\"auto, (max-width: 799px) 100vw, 799px\" \/><p id=\"caption-attachment-41636\" class=\"wp-caption-text\"><em>An aerial image of the site of the Jagersfontein tailing dam failure, showing a possible drawdown failure on the opposite side of the facility. <a href=\"https:\/\/www.youtube.com\/watch?v=XNcbLhwcI8A\">Still from a video posted to Youtube by News24.<\/a><\/em><\/p><\/div>\n<p><em>.<\/em><\/p>\n<p>This appears to me to be a slump in the dam walls, possibly associated with the drawdown of the tailings.\u00a0 This will have left transient high pore water pressures in the dam wall, allowing failure to develop.<\/p>\n<p>This is all captured rather nicely in <a href=\"https:\/\/www.planet.com\/\">Planet Labs<\/a> latest imagery from the site, collected on 12 September:-<\/p>\n<div id=\"attachment_41638\" style=\"width: 810px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-41638\" class=\"wp-image-41638 \" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-8.jpg\" alt=\"Satellite image showing the aftermath of the 11 September 2022 Jagersfontein tailings dam failure in South Africa. This image shows the tailings facility itself, including the multiple locations in which the walls have been compromised.\" width=\"800\" height=\"528\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-8.jpg 1173w, https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-8-300x198.jpg 300w, https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-8-1024x676.jpg 1024w, https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-8-768x507.jpg 768w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><p id=\"caption-attachment-41638\" class=\"wp-caption-text\"><em>Satellite image showing the aftermath of the 11 September 2022 Jagersfontein tailings dam failure in South Africa. This image shows the tailings facility itself, including the multiple locations in which the walls have been compromised. Image copyright <a href=\"https:\/\/www.planet.com\/\">Planet Labs<\/a>, used with permission.<\/em><\/p><\/div>\n<p>.<\/p>\n<p>The main breach is clear in the lower centre right of the image, but the other locations of substantial erosion, and the drawdown failure, can also be seen.\u00a0 As noted above, this image highlights the very urgent need to ensure that no further release of tailings occurs.<\/p>\n<p>Yesterday I noted that the slimes had managed to reach the main channel, but it was unclear as to how mobile they had become.\u00a0 The <a href=\"https:\/\/www.planet.com\/\">Planet Labs<\/a> satellite image below answers the question:-<\/p>\n<div id=\"attachment_41639\" style=\"width: 580px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-41639\" class=\"size-full wp-image-41639\" src=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-9.jpg\" alt=\"Satellite image showing the aftermath of the 11 September 2022 Jagersfontein tailings dam failure in South Africa. This image shows the slimes in the channel heading north from the mine site.\" width=\"570\" height=\"824\" srcset=\"https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-9.jpg 570w, https:\/\/blogs.agu.org\/landslideblog\/files\/2022\/09\/22_09-Jagersfontien-9-208x300.jpg 208w\" sizes=\"auto, (max-width: 570px) 100vw, 570px\" \/><p id=\"caption-attachment-41639\" class=\"wp-caption-text\">Satellite image showing the aftermath of the 11 September 2022 Jagersfontein tailings dam failure in South Africa. This image shows the slimes in the channel heading north from the mine site. Image copyright <a href=\"https:\/\/www.planet.com\/\">Planet Labs<\/a>, used with permission.<\/p><\/div>\n<p>.<\/p>\n<p>It is clear that the tailings have travelled down the main channel, extending many kilometres from the main site.\u00a0 Another priorty now must be to ensure that the slimes being retaining by the small dam at the bottom of this image do not mobilise again.<\/p>\n<p>Finally, <a href=\"https:\/\/www.news24.com\/fin24\/companies\/jagersfontein-disaster-dubai-based-owner-says-survey-showed-dam-was-safe-secure-20220912\">it now appears that the ownership of this facility changed earlier this year<\/a>, and that at the time of failure it was owned by Jagersfontein Developments, part of the Dubai-based Stargems Group.\u00a0 <a href=\"https:\/\/www.reuters.com\/world\/africa\/troubled-south-african-tailings-dam-had-history-high-water-levels-2022-09-12\/\">Reuters reports that the approach has been to reprocess the tailings to recover diamonds that have been accidentally dumped<\/a>.\u00a0 It also reports that operations were stopped in 2020 due to high water levels, but that they resumed in 2021.<\/p>\n<p>.<\/p>\n<h4>Reference and acknowledgement<\/h4>\n<p>Planet Team (2022). Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA. https:\/\/www.planet.com\/<\/p>\n<!-- AddThis Advanced Settings generic via filter on the_content --><!-- AddThis Share Buttons generic via filter on the_content -->","protected":false},"excerpt":{"rendered":"<p>Aerial and satellite imagery of the Jagersfontein tailings dam disaster highlights a complex failure event and high mobility of the slimes.<!-- AddThis Advanced Settings generic via filter on wp_trim_excerpt --><!-- AddThis Share Buttons generic via filter on wp_trim_excerpt --><\/p>\n","protected":false},"author":22,"featured_media":41638,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_members_access_role":[],"_members_access_error":""},"categories":[27393],"tags":[85,469,299,205,1205,8,114,230,1022],"class_list":["post-41629","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-mining","tag-africa","tag-featured","tag-mine","tag-mining","tag-planet-labs","tag-satellite-imagery","tag-south-africa","tag-tailings","tag-tailings-dam"],"_links":{"self":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/41629","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/users\/22"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/comments?post=41629"}],"version-history":[{"count":0,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/posts\/41629\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media\/41638"}],"wp:attachment":[{"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/media?parent=41629"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/categories?post=41629"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.agu.org\/landslideblog\/wp-json\/wp\/v2\/tags?post=41629"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}