2022-02-08_REVISION - M2008078

• Permit No: M2008078
• IBM Index Class Name: Revision
• Doc Date: 2/8/2022
• Doc Name: Adequacy Review Response
• From: Brannan Sand and Gravel Company, LLC
• To: DRMS
• Type & Sequence: SO4
• Email Name: SMS
• Email Name: AME
• Email Name: MAC
• Media Type: D
• Archive: No

minimum required MLRB safety factors for critical structures. The proposed setback of
85 feet from the edge of the ditch bank is satisfactory.
Case 3-2 - The resulting safety factors of 1.47 (static) and 1.24 (pseudo-static) during a
rapid drawdown condition exceed the minimum required MLRB safety factors of 1.3
(static) and 1.15 (pseudo-static)for non-critical structures. The resulting safety factors of
2.82 (static) and 2.14 (pseudo-static) during a full reservoir condition also exceed the
minimum required MLRB safety factors for non-critical structures. The proposed setback
of 75 feet from the edge of the highway parcel is satisfactory.
Case 3-3 - The resulting safety factors of 1.37 (static) and 1.16 (pseudo-static) during a
rapid drawdown condition exceed the minimum required MLRB safety factors of 1.3
(static) and 1.15 (pseudo-static) for non-critical structures. The resulting safety factors of
2.62 (static) and 1.99 (pseudo-static) during a full reservoir condition also exceed the
minimum required MLRB safety factors for non-critical structures. The proposed setback
of 65 feet from the edge of the highway parcel is satisfactory.
Case 4-1 - The resulting safety factors of 1.73 (static) and 1.42 (pseudo-static) during a
rapid drawdown condition exceed the minimum required MLRB safety factors of 1.5
(static) and 1.3 (pseudo-static) for critical structures. The resulting safety factors of 3.15
(static) and 2.32 (pseudo-static) during a full reservoir condition also exceed the
minimum required MLRB safety factors for critical structures. The proposed setback of
75 feet from the electric line/poles is satisfactory.
Case 4-2 -The resulting safety factors of 1.66 (static) and 1.38 (pseudo-static) during a
rapid drawdown condition exceed the minimum required MLRB safety factors of 1.5
(static) and 1.3 (pseudo-static) for critical structures. The resulting safety factors of 3.11
(static) and 2.31 (pseudo-static) during a full reservoir condition also exceed the
minimum required MLRB safety factors for critical structures. The proposed setback of
85 feet from the edge of the ditch bank is satisfactory.
Case 5-1 -The resulting safety factors of 1.39 (static) and 1.17 (pseudo-static) during a
rapid drawdown condition exceed the minimum required MLRB safety factors of 1.3
(static) and 1.15 (pseudo-static) for non-critical structures. The resulting safety factors of
2.55 (static) and 1.92 (pseudo-static) during a full reservoir condition also exceed the
minimum required MLRB safety factors for non-critical structures. The proposed setback
of 55 feet from the edge of the conservation easement is satisfactory.
Case 5-2 - The resulting safety factors of 2.69 (static) and 2.00 (pseudo-static) during a
rapid drawdown condition exceed the minimum required MLRB safety factors of 1.5
(static) and 1.3 (pseudo-static) for critical structures. The resulting safety factors of 4.13
(static) and 2.72 (pseudo-static) during a full reservoir condition also exceed the
minimum required MLRB safety factors for critical structures. The proposed setback of
75 feet from the edge of the canal bank is satisfactory.
Case 5-3 -The resulting safety factors of 1.64 (static) and 1.36 (pseudo-static) during a
rapid drawdown condition exceed the minimum required MLRB safety factors of 1.5
West Farm Gravel Pit Expansion
Slope Stability Analysis
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