Uncle Sam Side Slope I I Lateral Movement - Update 9 Presenter: Mosaic Fertilizer Date: February 11 2019 9? AGENDA l. Slope Observations ll. Water Management a. Stormwater b. Process Water Near-term Remedial Steps a. Stability Berm b. Factor of Safety IV. Contingency Planning V. Next Steps HEAVE OF THE GROUND IN FIELD NORTH OF STACK NO. 4 r' I NORTH SIDE-SLOPE sfQIENALTCRACKS . LNGLI I Fr . 7 (It LATERAL MOVEMENT OF CREST GYPSUM DIKE .- -WITH HIGHEST WERN. MOVEMENT GYPSUM STACK NO. 4 STAKES CREST . - - non CREST OF GYPSUM DIKE v. .. EAST GYPSUM BIKE CUMULATIVE LATERAL MOVEMENT (IN) 20.00 18.00 16.00 14.00 12.00 10.00 8.00 6.00 4.00 2.00 0.00 CUMULATIVE LATERAL MOVEMENT ALONG THE NORTH EARTHEN PERIMETER DIKE AS OF FEBRUARY 9, 2019 SINCE SURVEY STAKE INSTALLATION ON JANUARY 11, 2019 100 110 120 130 140 150 160 170 180 SURVEY STAKE ID 02/9/2019 CUMULATIVE LATERL MOVEMENT (IN) 12.00 10.00 8.00 6.00 4.00 2.00 0.00 195 CUMULATIVE LATERAL MOVEMENT ALONG THE CREST OF NORTH GYPSUM DIKE AS OF FEBRUARY 9, 2019 SINCE SURVEY STAKE INSTALLATION ON JANUARY 11, 2019 200 205 210 215 220 SURVEY STAKE ID 225 230 235 240 I 2/9/2019 CUMULATIVE LATERAL MOVEMENT (INCUMULATIVE LATERAL MOVEMENT ALONG THE MID-NORTH SLOPE AS FEBRUARY 9, 2019 SINCE SURVEY STAKE INSTALLATION ON JANUARY 28, 2019 .0 700 705 710 715 720 725 730 SURVEY STAKE ID 02/9/2019 BS was FEET DEPTH FROM TOP OF CASING LATERAL DISPLACEMENT (INCHES) 3007805040720 00 20 40 60 86100 LATERAL DISPLACEM ENT (INCHES) 4306C ?DISPLACEMENT PROFILES MEASURED ON 0207?? 9 SUMMARY OF LATERAL DISPLACEMENTS AT NORTH PERIMETER DIKE OF STACK NO. 4 (INCLINOMETER SI-N1) 0100 Ardaman Associates, Inc. Geotechnicai, Environmemal Materials Consultants CLAVEY SO TLS and MOSAIC FERTILIZER, LLC. UNCLE SAM PLANT Uncle Sam, Louisiana FILEND 1 8 ?3 043701 DFAWNEY KJ mimraav nrmavm av OZIDBHS mung PM:an Js?ianmn'Ewlg wasnam was ugmumomumsx LATERAL DISPLACEMENT (INCHES) LATERAL DISPLACEMENT (INCHES) 3100 75.0 00 5C 103 7100 50 00 5.0 ?00 CLAYFY SOILS 14: DEPTH FROM TOP OF CASING No?n??-i DISPLACEMENT PROFILES MEASURED ON 0126/19 Ardaman Associates, Inc. SUMMARY OF LATERAL DISPLACEMENTS Wm] AT NORTH BENCH OF STACK N0. 4 MOSAIC (INCLINOMETER SI-N2) UlirilceLgaim?oT?la KJ liftth 0.128119 r?u: NO A 18?90-3701 unsaamw LATERAL DISPLACEMENT (INCHES) LATERAL DISPLACEMENT 730 720 40 00 FEET DEPTH FROM TOP OF CASING DISPLACEMENT PROFILES MEASURED ON 02710719 SUMMARY OF LATERAL DISPLACEMENTS AT NORTH BENCH 0F STACK N0. 4 (SHAPEACCELARRAY SAA-N) 1C 20 ISO GYPSUM CLAYEY SOILS Ardaman Associates, Inc. Geotechnicai, Environmemal and Materials Consultants MOSAIC FERTILIZER, LLC. UNCLE SAM PLANT Uncle Sam, Louisiana DRAWN KJ CHECKED BY DATE 02f11i19 FILEND 1830?3701 nrpwavm av 10 unsaamw LATERAL DISPLACEMENT (INCHES) LATERAL DISPLACEMENT 730 720 40 00 FEET DEPTH FROM TOP OF CASING DISPLACEMENT PROFILES MEASURED ON 0271019 SUMMARY OF LATERAL DISPLACEMENTS AT WEST SIDE OF NORTH LOWER SLOPE OF STACK NO. 4 (SHAPEACCELARRAY SAA-NW) 20 ISO GYPSUM CLAYEY 50 LE Ardaman Associates, Inc. Geotechnicai, Environmemal and Materials Consultants MOSAIC FERTILIZER, LLC. UNCLE SAM PLANT Uncle Sam, Louisiana DRAWN BY KJ mimo BY DATE 02f11i19 FILEND 1830?3701 nrpwavm av 11 wasnam we DEPTH FROM TOP OF CASING SUMMARY OF LATERAL DISPLACEMENTS AT WEST SIDE OF MID-NORTH SLOPE LATERAL (INCHES) LATERAL DISPLACEM ENT 630 720 71C CLAVEY SOLE 100 i was-r EAST 190 . EL i SOUTH . i . A 200 DISPLACEMENT PROFILES MEASURED ON OZTO *9 OF STACK NO. 4 (INCLINOMETER SI-6B) Ardaman Associates, Inc. Geolechnicai, Envilonmemal and Materials Co nsultanls MOSAIC FERTTLIZER, LLC. UNCLE SAM PLANT Uncle Sam, Louisiana mm KJ EHFCKED av UHF BZI11I19 FILEND Ill-306701 nrmavm rcuRE 12 unmamw Mm- LATERAL DISPLACEMENT (INCHES) LATERAL DISPLACEMENT (INCHESFFET GYPSUM CLAVEY SOILS DEPTH FROM TOP OF CASING X- DIRECTION Y-DIRECTION DISPLACEMENT PROFILES MEASURED ON 02-10-19 SUMMARY OF LATERAL DISPLACEMENTS AT EAST SIDE OF NORTH LOWER SLOPEOFSTACKNO.4 (SHAPEACCELARRAY SAA-NE) Ardaman Associates, Inc. GeotechnicaI, Environmemal and II I II Materials Co n5ultanls MOSAIC FERTILIZER, LLC. UNCLE SAM PLANT Uncle Sam, Louisiana mm KJ av ms 02mm; nrmavm cung ??06701 13 Stormwater Management 4' - - 9 Proposal for routing storm-water from Let'dQW? p'pe 004 pipe Closed Slopes to 004 Duncan Existing Stormwater Conveyance (110 Acre Reservoir Diversion) New Pump I. .v W. New HDPE Pipe A New Berm Completed Berm Recently Completed Berm Phase 2 Ea?hen Berm .. "Lit - - Phase 1 berm could provide up to 14 acre I ft. of surge capacity and can utilize existing 004 pumps and piping Reduces pumps and blockages on southern portion of stack. Eanhen Berm Phase 2 berm could provide approx. 60 acre ft. of storm water retention J. Google Earth Mosaic" 15 Water Balance as of 2/10/19 Current Remaining Pond Volume Capacity Pond 4 615.0 - West Cell (Phase 1) 165.5 6.5 Surge Pond 31.3 3.6 Return Ditch 11.4 0.5 110 Acre Reservoir 156.9 212.? East Cell (Phase 2) - - Updated: 2110/19 4:00 AM 3/1/2019 Note: East Cell lining expected completion date wave? 15 Process Water Transfer Data and Timeline Approx. Approx. Pond Current Remaining Volume Capacity [MM?all Pond 4 605.0 - West Cell {Phase 1} 165.5 6.5 Surge Pond 31.3 3.6 Return Ditch 11.4 0.5 110 Acre Reservoir 168.0 191.6 East Cell {Phase 2} - - Updated: 2f11f19 4:00 AM Note: East Cell lining expected completion date 3/1/2019 2/9/2019 2/10/2019 3 2/11/2019 2/12/2019 5 2/13/2019 I 2/14/2019 1" 2/15/2019 2/16/2019 2/17/2019 3 2/18/2019 2/19/2019 5 2/20/2019 3' 2/21/2019 2/22/2019 2/23/2019 2/24/2019 5 2/25/2019 2/26/2019 5 2/27/2019 I 2/28/2019 1? 3/1/2019 3/2/2019 3/3/2019 3 3/4/2019 3/5/2019 5 3/6/2019 I 3/7/2019 3/3/2019 _l _l 110-AR Stormwater Diversion to 004 Pond 4 to 110 Acre water transfer* Expansion East Cell Liner Stability Berm Assuming average transfer of approximate 10 MMgal/Day 250 MMgal up to water el. +10. Remaining 3 ft of desgin F8 to account for 3 months of storm?water. 350 MMgal up to water el. +13. (Design Freeboard No additional storm-water capacity) Note: 110 Acre Reservoir Design Freeboard El. +13.0 ft. - Mosaic? 4? 16 Benefits of Continued Operation new 2 (MSL) ELEVATION IMPACT OF HYDROSTATIC PRESSURE ON GLOBAL GYPSUM STACK SLOPE STABILITY Fw1 2.59MM FW2 2.35MM 300 - . 24o - 240 150 ?750- - 760 -120 - 1 3 I I I I 200 +00 600 500 1000 1200 I 400 1500 1300 2000 2200 2400 2500 2500 3000 3200 3400 3500 3300 +000 4200 (MSL) FEET (MSL) ELEVATION OPERATION OF THE SOUTH WALL OF STACK No.4 PROTECTI FREEBOAR 30 FEET 60 FEET BERN. (TYP) POTATO A ROW mm? 25-30 FEET Fresh gypsum is placed in rim ditch 300 - 240- m- 120- _60_ ?120? ?180 FEET (MSL) ELEVATION Example of A New Lift NEW PROTECTI BERM (TYP) NEW POTATO POND WATER ROW LEVEL RIM DITCH 25-30 FEET Have? 23 Water Balance Impact of Idling Operations Continued operation of the - - Uncle Sam Process Water Balance Approximate Million Gallons PerYear Inputs From Operation 34.6 Outputs From Operation 404.6 Inventory Change I Rock Moisture Phosphoric Acid Moisture pd Fresh Water Inputs 52.6 Gypsum Pore Water 593.0 . Sulfuric Acid Moisture 9.6 Gypsum Hydration Water 168.0 be Process Reaction Water 19.0 Subtotal 115.8 1, 165.6 I Inputs Ongoing 906.8 Outputs Ongoing 700.0 Rainfall Injection Wells Phreatic Water Consolidation 341.6 Evaporation 434.0 Stacks 1?3 Drains 70.0 - Water tied up In gypsum slurry Subtotal 1,318.5 ?1.134.o Total lncludingOperation 1,434.3 2,299.6 (865.3) i Total Excluding Operation 1,318.5 1,134.0 184.5 Net Volume Change Operating Versus Down (1,049.8) million gallons per year - Water IS chemically bound In Note: Rainfall Input IS based on 62" per year formation of gypsum law's 24 - Operation of the gypsum stack system is beneficial from an overall water balance perspective due to about 2.7M gallons/day being removed as a result of production - Placement of gypsum on south dike does not increase forces on the north dike due to nature of gypsum placement and lateral distance between the two dikes Imam? 25 Stability Berm Construction as of 2/9/19 Total Fill Placed JTD: 79,500 :6de END OF SHIFT: 2l'Sf19 Section 2: Depth 2-4 (Approx: 15.500 cyd) 2? . .. .. [mimic WATER ELEVATION (FEET, MSL) WATER LEVEL ELEVATION ON STACK No.4 COM PARTM ENT VERSUS APPROXIMATE FACTOR OF SAFETY 194 1.02 1.04 1.06 1.08 APPROXIMATE FACTOR OF SAFETY .Without Stability Berm With Stability Berm 1.1 19 lnundation Scenario 185? to 180? Pond Elevation Change Key modeling assumptions - Release volume is worse case scenario with pond at elevation 185? at beginning of gailure and 180? at the en OVERVIEW mva-n-n - The initial elevation reflects level after 110 acre reservoir receives 200M gallons - Release volume is 159M gallons - Failure mode is unlikely to occur as rapidly as model estimates - Simulation reflects completion of El. 9? dike . . . . between perimeter dike and Lena-ml A, 1 5 nummou a VELOCITY WWINFEH - . mew-mm D- 5 SD DD grEE' - E24 - '1 H8 Geosyntecb Flame u5-1 Dal. - 10-20 ml: mm MMA mnm?mo?mm consde ASSLMEBM Fm ?Tim Mlh? Fm ma? WLCEHWLEENVETKR mom ?mm I 1? 1n All Runoff Water Monitoring pH and conductivity probe location Alarm text at: 3.0 pH 2,500 conductivity . i Iggigi?a??a' 26