Presented by Moustafa Gouda, P.E., D. GE, F.ACSE Director of Geotechnical & Environmental Engineering Services
Maser Consulting P.A. Planning Board Meeting, May 21, 2013
Second Presentation Geotechnical, Hydrological and
Environmental Assessment
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Comparison of Excavation
Phase I
• Hospital Engineer’s calculation 2010 excavation
• 173,090 CY of soil
• 2565 CY of rock
• Village Council Geotechnical Engineer’s calculation
2010 excavation
• 331,160 CY of soil
• 2519 CY of rock.
• Hospital Engineer’s calculation 2013 excavations
• 122,719 CY of soil
• 200 CY of rock 3
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Comparison of Excavation
Phase I
SOILS EXCAVATION PHASE I
2010
NORTH
BUILDING
CENTRAL
PLANT
PHILLIPS
GARAGE
ATRIUM
UTILITY TUNNEL
EARTH
EXCAVATION
TOTALS FOR
PROJECT
EARTH
EXCAVATION
TRUCK LOADS
TOTALS
REQUIRED FOR
PROJECT
82,227 CY
36,003 CY
44,431 CY
5,416 CY
5,013 CY
173,090 CY
11,539
PROPOSED 2013
41,261 CY
34,320 CY
44,431 CY
2,707 CY
0 CY
122,719 CY
8,181
DIFFERENCE
(40,966 CY)
(1,683 CY)
0
(2,709 CY)
(5,013 CY)
(50,371 CY)
(3,358)
REPRESENTS
APPROX. 50%
REDUCTION
FOR THE
NORTH
BUILDING
REPRESENTS
APPROX. 5%
REDUCTION
FOR THE
CENTRAL
PLANT
NO
CHANGE
REPRESENTS
APPROX.
50% REDUCTION
FOR ATRIUM
REPRESENTS 100%
REDUCTION
FOR THE UTILITY
TUNNEL. SERVICES
TO BE RUN WITHIN
THE BOILER
PLANT. BOILER
PLANT VALUES
ARE BLENDED
WITH CP
REPRESENTS
APPROX. 29%
REDUCTION
FOR EARTH
EXCAVATION
FOR THE
ENTIRE
PROJECT
REPRESENTS
APPROX. 29%
REDUCTION
FOR TRUCK
LOADS OF
EARTH
EXCAVATION
FOR THE
ENTIRE
PROJECT
Comparison of Excavation Phase I
ROCK EXCAVATION PHASE I
2010
NORTH
BUILDING
CENTRAL
PLANT
PHILLIPS
GARAGE
ATRIUM
UTILITY TUNNEL
ROCK
EXCAVATION
TOTALS FOR
PROJECT
ROCK
EXCAVATION
TRUCK LOADS
TOTALS
REQUIRED
FOR PROJECT
566 CY 1812 CY 187 CY ZERO ZERO 2,565 CY 171
PROPOSED 2013 ZERO 50 CY 150 CY ZERO ZERO 200 CY 12
DIFFERENCE (566 CY) (1,762 CY) (37 CY) ZERO ZERO (2,378 CY) (159)
REPRESENTS
APPROX. 100%
REDUCTION
FOR THE
NORTH
BUILDING
REPRESENTS
APPROX. 97%
REDUCTION
FOR THE
CENTRAL
PLANT
REPRESENTS
APPROX. 20%
REDUCTION
FOR THE
PHILLIPS
GARAGE
NO
CHANGE
NO
CHANGE
REPRESENTS
APPROX. 92%
REDUCTION FOR
ROCK
EXCAVATION
FOR THE ENTIRE
PROJECT
REPRESENTS
APPROX. 92%
REDUCTION
FOR TRUCK
LOADS OF
ROCK
EXCAVATION
FOR THE
ENTIRE
PROJECT
Excavation - Phase II
Hospital Engineer’s calculation for 2013 excavation
South Building
– 14,524 CY of soil and 0 CY of rock
West Building
– 31,674 CY of soil and 0 CY of rock
Total Phase II excavations
– 46,198 CY of soil and 0 CY Rock
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The Valley Upgrade
Excavation Quantity – Phase II
Proposed South Building Proposed West Building
44,000 SF gross area Proposed Finished floor 89 MSL Assume 6 inch slab at grade and 6 inch crushed stone Bottom of excavations 88 MSL Approximately 25,000 SF is within existing Bergen FF of
Bergen is 93 MSL depth of excavations 5 feet
Approximately 19,000 SF at existing parking area with
existing grade at 99 MSL depth of excavations 11 feet
45,600 SF Existing Grade 104 MSL Proposed Finished floor 89 MSL Assume 6 inch slab at grade and 6 inch crushed stone Bottom of excavations 88 MSL Depth of excavations 16 feet
Estimated Excavation Quantities @ 14.524 CY Estimated Excavations Quantities @ 31,674 CY
Methods of
Dewatering Disposal
Maximum amount of GPD dewatered
– 300,000 GPD
Average daily GPD flow
– 200,000 GPD
Three methods of disposal are available:
– Village Sanitary Sewer System
– Village Stormwater Sewer System
– Injection into bedrock
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Village Sanitary
Village Sewer System
• We have confirmed that Village System can
accommodate the maximum GPD –
300,000 GPD – to be dewatered
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Village Sanitary
Sewer System
Waste Water Plant located in Glen
Rock has enough capacity to handle flow
Plant was never overwhelmed during hurricanes/storms.
Pump station failure took place during hurricanes/storms
However, pipe carrying water/waste from hospital is a
gravity line that bypasses all pump stations.
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Village
Stormwater Sewer System
– Dewatering into the Village’s Stormwater Sewer
system will require a permit from the NJDEP
– Stormwater report confirms capacity to handle
anticipated flow:
• Existing 36” stormwater pipe down Meadowbrook Ave
• Full Capacity : 17,700,000 GPD
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Injection Wells for
Dewatered Water
• The hospital could effectively use deep
injection wells located on its campus to
dewater the maximum GPD
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Injection of Dewatering Water
• One of the Hospital’s current deep irrigation wells
yields 135 GPM, i.e. 194,000 GPD.
• New wells will be installed prior to dewatering to accommodate anticipated flow /300,000 GPD
• The wells:
• will extend to a minimum of 150-300 feet deep
• be cased to a minimum of 50 feet into the bed rock
• and the casing will be sealed with cement grout
• Injection of water 150 to 300 feet deep into bedrock will not affect the groundwater or raise the area groundwater table
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Injection Well Details
Graphic depiction of Injection Wells
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Dewatering Plan
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Cone of Depression
Perspectives
Two Perspectives
– Contour Map
– Cross Section Diagram
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Effect of Hospital Dewatering
-Existing Structures/Facilities
Settlement in sand/gravel due to stress change
(loss of buoyancy) is fast, happens quickly and
has already taken place due to past water
fluctuations
Once settlement takes place it causes soils to
over consolidate.
Soils will not settle anymore due to dewatering,
as past water fluctuations are greater than
fluctuations to be caused by dewatering
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Effect of Hospital Dewatering
-Existing Structures/Facilities
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Effect of Hospital Dewatering
-Existing Structures/Facilities
A Settlement Analysis was performed
to evaluate the effect of dewatering
Actual soil condition in the area based on available information is Medium to Dense state of density.
However, we performed the settlement analysis assuming three state of density conditions:
– Dense soil
– Medium soil
– Loose soil
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Effect of Hospital Dewatering
- Existing Structures/Facilities
– Using a widely used method developed by Dr.
Schmertmann of Florida, past settlement as a result
of lowering the water table by 10 feet ranges from
a negligible .06 to .04 inches.
– The soils under the homes are now consolidated and will
not settle again during dewatering, as lowering of the water
table will be less than what has occurred over the last
two years due to natural groundwater fluctuation.
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Effect Of Hospital
Dewatering - Allocation
Water Allocation
• The hospital’s project and need for dewatering
will not count toward the Village’s allocation of
water from the NJDEP
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Effect Of Hospital
Dewatering - Allocation
– Village allocation is not charged
when another Village party is pumping water
– To obtain NJDEP Pumping Permit, Hospital
must demonstrate that wells in the area are
not affected
– All Village wells are located outside the three
cones of depression. Therefore, hospital
dewatering will not impact the wells
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Effect Of Hospital Dewatering - Well Inventory
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Effect Of Hospital Dewatering - Central Plant
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Effect Of Hospital Dewatering - North Building
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Effect Of Hospital Dewatering - Garage
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Liquefaction Analysis
Soil liquefaction describes a phenomenon
where by a saturated loose soil substantially
loses strength in response to an applied shaking,
usually earthquake, causing it to behave like a liquid,
e.g. Quicksand.
Liquefaction Analysis, using the Harry Seed and M. Idris
method and several boring tests, determined that
liquefaction will not take place
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Confirmation of Seismic Class
2010 Geotechnical Report recommendation:
– Seismic Class B for North Building/Central Plant because building foundations were within 10 feet of Bedrock.
The International Building Code (IBC) allows the use
of Seismic Class B.)
2013 Amended Master Plan recommendation:
– Seismic Class D for North Building/Central Plant because building foundations will be more than 10 feet above the bedrock.
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