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Fundão Tailings Dam Review Panel
Report on the Immediate Causes of the Failure of the Fundão DamAppendix E - Samarco Field Monitoring Data
August 25, 2016
ATTACHMENT E5 Flow Data
Fundão Tailings Dam Review Panel Report on the Immediate Causes of the Failure of the Fundão Dam Appendix E - Samarco Field Monitoring Data
August 25, 2016 Page E.E5-i
Attachment E5 Flow Data
TABLE OF CONTENTS
E.E5-1 GENERAL ................................................................................................................................. 1 E.E5-2 FLOW MEASUREMENT MONITORING STATION DETAILS ....................................................... 2
List of Figures
Figure E.E5-1 Dike 1 flow monitoring locations ............................................................................................... 1
Fundão Tailings Dam Review Panel Report on the Immediate Causes of the Failure of the Fundão DamAppendix E - Attachment E5 – Flow Data
August 25, 2016 Page E.E5-1
E.E5-1 GENERAL
This attachment presents flow monitoring data from six locations at the Fundão Dam. Data was compiled from Samarco’s instrumentation reports, weekly reports, and MDGEO’s Hydrogeological Study on the 940 m Raise[7]. The locations are shown in Figure E.E5-1 and are numbered according to the numbering system used in Samarco’s weekly reports. The locations were estimated based on site photos and aerial images. Coordinates for the flow monitoring stations are not available. Details on the individual locations and their period on record are presented in Section E.E5-2.
Figure E.E5-1 Dike 1 flow monitoring locations
Fundão Tailings Dam Review Panel Report on the Immediate Causes of the Failure of the Fundão DamAppendix E - Attachment E5 – Flow Data
August 25, 2016 Page E.E5-2
E.E5-2 FLOW MEASUREMENT MONITORING STATION DETAILS
The factsheets below provide details on each of the flow monitoring locations.
Location 1: Fundão Toe Drain Description
Data Collection Method Measured flow through Parshall flume (pictured below).
Period on Record and Data Sources March, 2013 – October, 2015 (instrumentation reports) February, 2015 – October, 2015 (weekly reports) March, 2013 – May, 2015 (MDGEO)
Additional Information
Parshall flume located at the outlet of the Principal Foundation Drain. It is unknown why there are no records prior to 2012. From photographs it appears that the flow was measured using both a pressure transducer and a staff gauge.
Photo and Location
Approximate location. October 1, 2015 Samarco aerial image
shown.
Photo from weekly report, week of October 25, 2015,
showing Parshall flume.
July, 2014 VOGBR site inspection photo showing Parshall
flume.
July, 2014 VOGBR site inspection photo showing Parshall
flume.
Fundão Tailings Dam Review Panel Report on the Immediate Causes of the Failure of the Fundão DamAppendix E - Attachment E5 – Flow Data
August 25, 2016 Page E.E5-3
Data
Measurements from Samarco instrumentation report, MDGEO’s Hydrogeological Study on the 940 m Raise[7], and Samarco
weekly operations reports. Note that not every weekly report in the given interval provides a flow measurement at this location.
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0
2
4
6
8
10
12
14
16
Flow
(L/s
)
Flow
(m3 /
h)
Fundão Toe Drain Instrumentation Report MDGEO Report Weekly Reports
Fundão Tailings Dam Review Panel Report on the Immediate Causes of the Failure of the Fundão DamAppendix E - Attachment E5 – Flow Data
August 25, 2016 Page E.E5-4
Location 2: El. 826 m Drain (“Kananets®”) Description
Data Collection Method Total flows given in weekly reports measured using Parshall flume. No information is available on how the individual flows in each pipe were measured.
Period on Record and Data Sources December, 2013 – October, 2015 (instrumentation reports, total flow) February, 2015 – October, 2015 (weekly reports, total flow) April, 2011 – July, 2015 (MDGEO, measurements from individual Kananets)
Additional Information
27 Kananet® pipes were installed in the El. 826 m blanket drain and discharged to a concrete channel on the El. 820 m bench. Samarco’s drainage plan[57] and a 2011 ITRB report state that drainage from the Kananets® was towards both the right and left abutments. However, measurements are only available from a flume near the right abutment. Sections taken along the El. 820 m berm show that the topography was sloped towards the right abutment over the majority of the berm, with less than 50 m length sloped toward the left abutment. The last 4 to 5 Kananets® may have drained to the left abutment. However, the sum of individual Kananet® flows[7] is very similar to the total flow measured on the right abutment (reported in weekly reports). Any drainage to the left abutment was likely a small percentage of the total flow.
Photo and Location
Photo from weekly report, week of October 25, 2015,
showing Parshall fume. Actual photo date unknown. Photo looking towards center of dam and left abutment.
Photo from MDGEO Hydrogeological Study on the 940 m Raise[7], taken June 23, 2015. Photo looking towards right
abutment showing concrete channel and Kananets®.
Approximate location. October 1, 2015 Samarco aerial image shown.
Fundão Tailings Dam Review Panel Report on the Immediate Causes of the Failure of the Fundão DamAppendix E - Attachment E5 – Flow Data
August 25, 2016 Page E.E5-5
Location 2: El. 826 m Drain (“Kananets®”)
Figure 6.1 from MDGEO’s Hydrogeological Study on the 940 m Raise[7], showing Kananets® numbered 1 to 27 from the right
abutment to the left abutment.
Fundão Tailings Dam Review Panel Report on the Immediate Causes of the Failure of the Fundão DamAppendix E - Attachment E5 – Flow Data
August 25, 2016 Page E.E5-6
Location 2: El. 826 m Drain (“Kananets®”) Data
Total measurements (sum of flow in 27 pipes) from Samarco instrumentation report, MDGEO’s Hydrogeological Study on the
940 m Raise[7], and Samarco weekly operations reports. Note that not every weekly report in the given interval provides a flow measurement at this location.
0
10
20
30
40
50
60
70
80
90
0
50
100
150
200
250
300
350
Flow
(L/s
)
Flow
(m3 /
h)
El. 826 m Drain ("Kananets®")Instrumentation Report MDGEO Report Weekly Reports
Fundão Tailings Dam Review Panel Report on the Immediate Causes of the Failure of the Fundão DamAppendix E - Attachment E5 – Flow Data
August 25, 2016 Page E.E5-7
Location 3: Grota da Vale Description
Data Collection Method Data collection prior to October 2014 unknown. Measurements assumed to be taken at flume after October 2014.
Period on Record and Data Sources February, 2013 – October, 2015 (instrumentation reports) February, 2015 – October, 2015 (weekly reports)
Additional Information
Prior to October, 2014, it appears that data was collected from the pump barge in Grota da Vale (“Location A”). It is not clear whether the values are the pump rate or the discharge rate from an outlet pipe. It is possible that the flow was being measured in the concrete channel at the outlet of the Secondary Gallery (See below, “Alternative Location A”). After the construction of the left abutment concrete channel in October, 2014[58], flows appear to be measured using a flume at this location (“Location B”).
Photo and Location
Approximate Location A. October 1, 2015 Samarco aerial
image shown.
Alternative Location A. September 26, 2014 Samarco aerial
image shown.
Photo from weekly report, week of October 25, 2015,
showing Parshall flume (Location B).
Approximate Location B. October 1, 2015 Samarco aerial
image shown.
Fundão Tailings Dam Review Panel Report on the Immediate Causes of the Failure of the Fundão DamAppendix E - Attachment E5 – Flow Data
August 25, 2016 Page E.E5-8
Location 3: Grota da Vale Data
Measurements from Samarco instrumentation report and Samarco weekly operations reports. Note that not every weekly
report in the given interval provides a flow measurement at this location.
0
2
4
6
8
10
12
0
5
10
15
20
25
30
35
40
45
Flow
(L/s
)
Flow
(m3 /
h)
Grota da ValeInstrumentation Report Weekly Reports
Fundão Tailings Dam Review Panel Report on the Immediate Causes of the Failure of the Fundão DamAppendix E - Attachment E5 – Flow Data
August 25, 2016 Page E.E5-9
Location 4: El. 855 m Drain Description
Data Collection Method Data collection method unknown.
Period on Record and Data Sources November, 2014 – October, 2015 (instrumentation reports) February, 2015 – October, 2015 (weekly reports)
Additional Information The El. 855 m drain was constructed in response to the seepage incident at the right abutment in 2014 (see Appendix B Attachment B1 and Attachment B8).
Photo and Location
Photo from weekly report, week of October 25, 2015,
showing concrete channel and drainage pipes leading from the El. 855 m drain.
Approximate location. October 1, 2015 Samarco aerial image
shown.
Data
Measurements from Samarco instrumentation report and Samarco weekly operations reports. Note that not every weekly
report in the given interval provides a flow measurement at this location.
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
0.45
Flow
(L/s
)
Flow
(m3 /
h)
El. 855 m DrainInstrumentation Report Weekly Reports
Fundão Tailings Dam Review Panel Report on the Immediate Causes of the Failure of the Fundão DamAppendix E - Attachment E5 – Flow Data
August 25, 2016 Page E.E5-10
Location 5: El. 860 m Drain Description
Data Collection Method Data collection method unknown.
Period on Record and Data Sources January, 2015 – July, 2015 (instrumentation reports) February, 2015 – October, 2015 (weekly reports)
Additional Information
The El. 860 m drain was constructed in response to the seepage incident at the right abutment in 2015 (see Appendix B Attachment B1 and Attachment B8). According to weekly reports, flows were not reported from July, 2015 to the end of October, 2015 due to on-going work in the area.
Photo and Location
Photo from weekly report, week of October 25, 2015,
showing El. 860 m Drain.
Approximate location. October 1, 2015 Samarco aerial image
shown. Data
Measurements from Samarco instrumentation report and Samarco weekly operations reports. Note that not every weekly
report in the given interval provides a flow measurement at this location.
0.00
0.02
0.04
0.06
0.08
0.10
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.40
Flow
(L/s
)
Flow
(m3 /
h)
El. 860 m DrainInstrumentation Report Weekly Reports
Fundão Tailings Dam Review Panel Report on the Immediate Causes of the Failure of the Fundão DamAppendix E - Attachment E5 – Flow Data
August 25, 2016 Page E.E5-11
Location 6: Borehole Description
Data Collection Method Measurements recorded from weir (pictured below).
Period on Record and Data Sources December, 2014 – October, 2015 (instrumentation reports) February, 2015 – October, 2015 (weekly reports)
Additional Information
Flow monitoring station located downstream of the remnants of the Principal Foundation Drain. This is in the same area as the “Toe” piezometer group. Piezometers and this flow monitoring station were installed in March, 2015.
Photo and Location
Photo from weekly report, week of October 25, 2015,
showing weir.
Approximate location. October 1, 2015 Samarco aerial image
shown. Data
Measurements from Samarco instrumentation report and Samarco weekly operations reports. Note that not every weekly
report in the given interval provides a flow measurement at this location.
0.00
0.05
0.10
0.15
0.20
0.25
0.30
0.35
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
Flow
(L/s
)
Flow
(m3 /
h)
BoreholeInstrumentation Report Weekly Reports