20170359 Ver 3_More Info Received_20241017

April 18, 2024 Version 2.1
Grandfather Golf & Country Club Maintenance Dredging
Turbidity Management and Response Plan
Field Procedure:
1. Turbidity sampling (grab samples tested onsite via calibrated metering device) will be employed
beginning one week prior to and during in -water work —see Schedule.
2. One sample will be taken upstream of dredging operations where the Linville River crosses fairway
17 at sample station A (see map).
3. One sample will be taken from the outlet of a stormwater pipe that carries flows from offsite,
underneath Hwy 105, and into Loch Dornie at station B (see map).
4. One sample will be taken within Loch Dornie itself from the release valve platform at station C
(see map).
5. One sample will be taken downstream of Loch Dornie, downstream of the confluence of the
release pipe channel and the spillway overflow channel at station D (see map).
6. Date, time, turbidity reading, and weather conditions (e.g., temperature, precipitation), will be
recorded for each sampling. Construction activity and changes to flow diversion and turbidity
control measures will also be recorded. Values of turbidity and weather conditions will be tracked
and graphed.
Benchmark and Response Actions:
1. If the lake (station C) and downstream (station D) sample site turbidity is equal to or less than the
maximum allowable turbidity per the Section 401 Water Quality Certification, dredging may
continue.
2. If the lake and downstream turbidity is the same as or lower than the upstream turbidity (e.g., 25
NTU enters, 25 NTU leaves), dredging may continue.
Hazen and Sawyer Grandfather Golf & Country Club

April 18, 2024
Version 2.1
3. If downstream site measurements exceed conditions under #1 or #2 above, active dredging is to
cease immediately until condition #1 or #2 are met again; water flow diversion and turbidity
control measures (e.g., turbidity curtains) are to be examined and adjusted as needed for effective
operation.
Schedule:
1. Testing at locations A, B, C, and D shall be daily, on dredging operation days, defined as days when
machinery actively operates, moving soil or dredge material, below the pre-drawdown water
surface elevation. Turbidity sampling on dredging operation days will be performed
approximately two hours after in -water work commences.
2. Testing is to begin prior to in -water work by one week, minimum, to establish a "baseline;" see
#2 under "Benchmark and Response Actions" above.
3. If conditions #1 or #2 under "Benchmark and Response Actions" can be demonstrated for one
calendar week, then testing may be relaxed to three times a week (e.g., Monday, Wednesday,
Friday). If testing is relaxed to three times a week, turbidity will be visually monitored on non -
testing, dredging operation days.
4. Violations of #1 or #2, as applicable, under "Benchmark and Response Actions" during "relaxed"
timeframes will re -impose daily testing requirements.
5. After the dredging work has been initiated, if there are extended periods of time (one week or
longer) with no dredging activity for reasons other than violation, sampling may be relaxed to
three times per week (e.g., Monday, Wednesday, Friday).
Hazen and Sawyer Grandfather Golf & Country Club