20210330_Pump_OM_plan

OPERATION AND MAINTENANCE PLAN
SAND MINE DEWATERING AND WATER LEVEL CONTROL STRUCTURE
Operator: HOM Development, LLC,1002 Driftwood Drive, Manteo, NC 27954
Job Location: Foster Forbes Mine, 8180 Caratoke Hwy., Powells Point, NC 27966
County: Currituck County
Prepared by: Ken Elliott, consulting
Date: March 17, 2021
This plan defines responsibilities for operating, inspecting, and maintaining equipment and structures
used for constructing and dewatering the Foster Forbes Mine safely, and that dewatering will not
degrade or negatively impact any wetlands or waters of the state.
Description and Operation of the Foster Forbes Mine:
The Foster Forbes Mine is a proposed 6.23-acre sand mine excavation operated by HOM Development,
LLC, Jamie Basnight Hatchell, operator, in a 41-acre permit area located at 8180 Caratoke Highway,
Powells Point, NC, in Currituck County. The permit area is on high sandy land and is currently a
cultivated farm field owned by Mr. Foster Allen Forbes, 5104 Lunar Drive, Kitty Hawk, NC. At this time
HOM Development is applying for a mining permit with the NCDEQ Division of Energy, Mineral and Land
Resources to construct the sand mine and begin operation in June 2021. HOM Development is also
applying for a Use Permit from the Currituck County Planning Department for construction of this mine.
Sand Mine Dewatering:
It will be necessary to dewater the pond as it is being excavated to allow excavating equipment to enter
the area safely and efficiently remove the sand from the pond bottom. This will allow for full permitted
depth excavation of the pond and proper reclamation of the edges of the pond. It is the intention of
HOM Development to only dewater the excavation as needed, which will not entail full-time
dewatering.
For excavation purposes, dewatering will occur roughly every 30 days which will allow excavating
equipment to remove approximately 150 loads of sand up to ground level where it will be stockpiled for
later use. When the stockpile is depleted from usage, the excavation area will again be dewatered, and
another quantity of sand will be excavated.
Mine dewatering wastewater will be treated before release to the Waters of the State. Use of a
sedimentation pond separate from the excavated mine is a traditional and effective means to remove
sediment from wastewater generated during mine dewatering operations.
Sedimentation Pond Construction and Overflow Discharge:
HOM Development proposes to utilize an existing 0.51-acre excavation located 90 feet east of the
proposed 6.23-acre excavation as a sedimentation pond. The pond's sides will be enhanced with the
addition of 5-ft tall sand berms 30 feet wide at the base with 3:1 exterior slope and 2:1 interior slope.

All exposed slopes and peaks of the berms will have full ground cover. The pond berms will have a
minimum 1.5 feet of freeboard between the water surface and the top of the sediment pond bank.
Excavation of the main 6.23-acre pond will begin approximately 90 feet from the sediment pond and
work westward and southward. The edge of the sediment pond berm and main excavation will be 75
feet from the nearest wetland swamp. Use of the sediment pond will help forcibly hydrate the nearby
wetlands located north and west of the sediment pond and will minimize dehydration of the wetland
forest.
Sediment pond water level will be controlled by a half -pipe water height control device with a flash
board riser installed in the north edge of the sediment pond berm. This control structure will allow
water to flow across the flash boards into a 25ft long x 15" wide buried PVC pipe leading northward
through the berm 25 feet to a 6-ft wide lined discharge ditch running 195 feet northward until exiting
into the Foster Forbes Ditch blue -line stream. Overflow water will then travel westward and southward
1.12 miles through PFO1/2F (USFWS) semi -permanently flooded Palustrine wetland forest, then 0.17-
mile westward through E2EM1Pd (USFWS) partially flooded estuarine wetlands, and then 0.7-mile
westward through an unnamed tributary to Albemarle Sound.
Dewatering Procedure:
The operator will install an 8-inch diesel engine powered dewatering pump at the south end of the
sediment pond,1300 feet from the closest residence outside of the landowner's property and situated
behind sand berms or below natural ground level to reduce noise. Discharge from the dewatering pump
will flow northward 320 feet from the south end of the sediment pond to the flash board riser overflow
on the northeast end, then eastward 0.7-mile as described earlier to Currituck Sound.
Water will be pumped from the main pond to the sediment pond by the Bin gasoline -powered transfer
pump operating at idle speed. Estimated maximum flow from the pump will be 2,000 gallons/hour,
operating 12 hours per day, 0.024 mgd. The operator proposes to drop the water level in the main pond
approximately 20 - 25 feet below normal ground level when needed.
Time and distance will allow all sedimentation to occur to acceptable levels before the overflow water
reaches outfall and then the waters of the State. Water will have to travel a minimum of 270 feet to
reach the overflow point which will give enough surface area to allow sufficient sedimentation to occur.
Stormwater drainage will be unable to enter the sediment area and damage the sediment pond rates,
due to the height of the surrounding sediment pond berm.
Wetlands Protection:
To minimize wetland impacts, the operator will construct a 1260-foot long by 10-ft wide rim ditch
between the west side of the proposed excavation and the adjacent wetlands 75 feet westward. The
ditch will run along the westward edge of the 25-ft wide unexcavated buffer between the perimeter
berm and the 50-ft wide undisturbed buffer boundary. The ditch will be kept artificially full by having
water pumped into it from the excavated pond on a constant basis. Water will be allowed to overflow
along its length and spread in a sheet flow across the foliated undisturbed buffer into the adjacent

wetlands. This will help forcibly hydrate and enhance groundwater level between the excavation and
adjacent wetlands. This sheet flow will be in addition to the regular overflow water entering the same
wetlands from the sediment pond.
Groundwater Control:
Groundwater level can be controlled by a planned program of dewatering. Mine dewatering typically
provides more efficient working conditions, better diggability and trafficking, improves slope stability
and safety, and maintains or increases safety factors.
The top edge of the southeastern corner of the proposed excavation is located 850 feet from the closest
residence at 8200 Caratoke Highway. There are seven homes and businesses with water supply wells
within 1500 feet of excavation edge. The operator proposes to address possible groundwater impacts
through two methods:
• The operator will install two groundwater level monitoring wells along the eastern permit
boundary adjacent to Caratoke Highway, exact location to be determined by recommendation
from engineers with Currituck Planning and Community Development. Once permits are issued
and wells installed, wells will be monitored and measured monthly during the life of the permit.
Baseline water level measurements will be taken as soon as wells are installed and before
dewatering operations begin, then monthly thereafter. Monthly groundwater level
measurements will indicate abnormal groundwater depletion if it starts to occur, and measures
can be taken to adjust dewatering procedures before reaching damaging levels.
• In response to requirements of the Currituck County Unified Development Ordinance for mine
dewatering activities, the operator will establish and maintain a performance bond of $3000 for
each in -use water well within 1500 feet of the proposed excavation. The bond will be used to
repair or replace any groundwater wells or pumps damaged by dewatering at the proposed
excavation. The bond will be in the form of an irrevocable letter of credit held by Currituck
County Planning, estimated at this time to be $21,000. Exact number of wells to be covered and
total bond amount will be determined before permit is issued.
Sedimentation and Erosion Control:
The wetland swamp west of the proposed excavation, located 75 feet from the excavation edge, runs
parallel to the western permit area boundary. The operator will establish a SO-ft wide undisturbed
buffer (no disturbance of any kind) as a visual screen of existing woodland which is part of the Currituck
County required property line setback. This buffer will be adjacent to, and inside of, the permit
boundary. This buffer will be maintained by the operator as grass and pine tree ground cover.
In addition, there will be a 25ft unexcavated buffer (may contain roadways, stockpiles, and sediment &
erosion control devices) around the entire excavation area, between the excavation and the
undisturbed buffer.

Sediment pond overflow will drain into an operator -maintained 6ft wide feeder ditch that leads 185 feet
to the Foster Forbes Ditch blue -line stream, then two miles to the Albemarle Sound. Overflow into the
feeder ditch will be stabilized by riprap installed in the feeder ditch at the overflow (see diagram) to
prevent erosion of the ditch.
All erosion and sedimentation will remain inside of the permit area. The operator will construct and
maintain an 8-ft wide x 2-ft tall grass -covered sand berm around the perimeter of the current affected
area of the excavation during all phases of operation. During mining operations and dewatering, most
of the water leaving the excavation will remain inside of the permit area and will only overflow through
the sediment pond occasionally. The sediment pond will be approximately 5 feet deep, and there is a
sand layer below the bottom of the area. The porosity of the soil under the sediment pond will allow
most of the water pumped into the pond from dewatering to seep back into the ground naturally. Any
excess water overflowing from the sediment pond will flow downstream two miles to Albemarle Sound.
Maintaining the Sediment Pond Overflow Control Structure, Sedimentation Pond and Ditches:
Inspections and maintenance are required to obtain the intended function of safely dewatering the sand
mine, and to maintain the life of any adjacent wetlands or waters of the State. Items to inspect and
maintain during the anticipated 6-year life of the mine dewatering permit are:
• Inspect the water control structures regularly, especially following heavy rains and runoff, or
during periods of operation of the structure.
• Remove accumulated debris from the overflow control structure.
• Inspect the structure for excessive settlement or seepage.
• Inspect all components of the structure, including appurtenances, and repair or replace any
damaged items as needed.
• Inspect embankments, berms and appurtenant structures, and repair as needed.
• Repair any damage to vegetated areas or berms with compacted earth fill, reshaping, sodding,
reseeding, and mulching as needed.
• Inspect riprap outlet stabilization structures in ditches regularly, replace dislodged rock as
necessary.
• Promptly repair all leaks in delivery facilities by replacing valves, fittings, gaskets, and worn or
damaged parts.
• Maintain all screens, filters, valves, timers, and other electrical and mechanical equipment in
good operating condition, following manufacturer's recommendations
Monitoring the Dewatering Process and Effects of Dewatering:
Analytical and qualitative monitoring of mine dewatering wastewater will be in accordance with the
NCG020000 permit, as follows:
• All ponds in the Foster Forbes Mine permit area will be inspected daily by the operator to
identify any abnormal conditions.

• All berms and erosion control and sedimentation control structures will be inspected for
damages monthly and within 24 hours after every storm event greater than 1.5 inches, and all
structures will be repaired immediately.
• Special inspections will be conducted immediately following severe storms, vandalism, and
other significant events.
• Dewatering process will be inspected daily during periods of dewatering the excavation.
• Overflow of wastewater process will be inspected daily during periods of dewatering the
excavation.
• Outflow of dewatering wastewater will be monitored quarterly at the overflow exit stabilization
structure for chlorides, pH, suspended solids, settleable solids, turbidity, and total flow.
Samples will be collected and tested onsite for pH, and the remainder will be tested for the
remaining parameters by a North Carolina certified lab.
• Rain gauge data will be collected by monitoring rain gauge data monthly and after each rain
event.
Wetlands Monitoring:
Wetlands are located westward and northward of the proposed Foster Forbes Mine site. Level 1
wetlands landscape assessment by US Fish & Wildlife Service indicate two types of wetlands on the
Foster Forbes Parcel parcel:
• Seasonally flooded, partially drained, Palustrine scrub/shrub wetlands, and
• Irregularly flooded, partially drained, emergent estuarine wetlands.
Level 2 wetlands assessment was performed in January 2021 by Quible and Associates and the
delineated wetland line will be confirmed in late March 2021 by USACE. Delineation places the edge of
wetlands 75 feet from the closest edge of proposed excavation.
During mine dewatering activities wastewater will be treated in a sediment pond to allow settlement of
suspended solids and reduction of turbidity. Wastewater overflow will then be discharged into an
existing ditch east of the sediment pond running westward into the wetlands, helping to recharge
wetland water levels that may be affected by dewatering. Quality of water entering the discharge ditch
and wetlands will be monitored at the discharge point for total suspended solids, settleable solids,
turbidity, pH, chlorides, and flow rate. Ditch flowing into the wetlands will be monitored weekly for
evidence of sedimentation or erosion,
Records
Data will be collected as follows:
• Data will be collected from samples taken from the wastewater point source discharge in
operation at the time.

• Point source discharge data: data from the site taken quarterly, date & time, general weather
conditions, pH of sample, status of process at point source, inlet, or outlet, other DWQ required
data.
• Visual monitoring of adjacent wetlands and farmland for potential dehydration during mining or
dewatering activities will take place weekly. Solutions to any degradation caused by any mining
activity will include alteration of dewatering process. DWQwill be consulted as needed;
alterations to process will be recorded.
• Elliott Consulting will maintain the following records in a permanent file at the Elliott Consulting
office at PO Box 112, 202 Elliott Road, Aydlett, NC 27916: a record of all significant actions
taken; as -built drawings; permits; analytical results from sampling; and related material. Copies
of all inspections, monitoring reports and lab analyses shall be provided to NCDWQ on a regular
basis and as requested.
BMP Conditions
• The permittee will utilize best management practices to ensure that dewatering the Foster
Forbes Mine will not degrade or negatively impact any wetlands or waters of the State. BMP's
will include:
o Sediment pond outlet structure with flashboard riser located at edge of pond for ease of
maintenance.
o All berms and erosion control and sedimentation control structures will be inspected for
damages monthly and within 24 hours after every storm event greater than 1.5 inches,
and all structures will be repaired immediately.
o Sediment pond outlet ditch will have rock lining or riprap stone layer to prevent erosion,
scour or sloughing of embankment.
• The permittee shall obtain authorization from the Director of the NCDEMLR and the Stormwater
Program chief prior to utilizing any chemical flocculants at the Foster Forbes Mine.
Signed,
Ken Elliott
for HOM Development, LLC, Jamie Basnight Hatchell, Manager
March 19, 2021