HomeMy WebLinkAboutNC0062413_Wasteload Allocation_19911002NPDES DOCUMENT SCANNING COVER SHEET
NPDES Permit:
NC0062413
Linville Ridge Country Club WWTP
Document Type:
Permit Issuance
asteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Engineering Alternatives (EAA)
Compliance
Instream Assessment (67b)
Speculative Limits
Environmental Assessment (EA)
Document Date:
October 2, 1991
This document is printed fart reuse paper - ignore any
can -teat on the reYerse side
DIVISION OF ENVIRONMENTAL MANAGEMENT
MEMORANDUM
TO: Dale Overcash
FROM:
THRU: Carla Sanderson
Jacquelyn M. Nowell
October 2, 1991
SUBJECT: UT West Fork Linville River Flows for Linville Ridge Development
NPDES No. NC0062413
Avery County
Per your comments on the May 10, 1991 memo to you concerning the subject
facility, attached are two USGS sites near the existing discharge point where pos-
itive 7Q10 flows have been estimated. I have also included a map of the sites so
that the distance from the current site can be seen.
If there are any questions, please contact me.
cc: WLA File
•
DATE 0/5/
REQUEST No. 9/9�
USGS Flow Data Request
Requested by: 7L6 �(
SITE No. 1 County AvRiver Basin efts
NRCD Sub Basin 0 3`'83`' Map No. or Name Cafe
l -
Station No. 6.2/ 38Z 3'S SJ Secondary or Primary Road No.
Stream Name
f
Data Requested: Drainage Area Av Frage low_k _ 30 Q 2
Winter 7 Q 10 ____— Summer 7 Q 10
submit ; request and map in duplicate.
Stream Name
SITE No. 2
NRCD Sub Basin
County A_;-
03o '30
River Basin
Map No. or Name C/fsf
Station No. 02 /312 Secondary or Rimary Road No.
„ir
Data Requested: Drainage Area Aver ge Flow ✓ 30 Q 2 ✓
Winter 7 Q 10 Summer 7 Q 10 ✓
when making a request for data, plPase
SITE No. 3
County River Basin
NRCD Sub Basin Map No. or Name
Station No. Secondary or Primary Road
Stream Name
Data Requested: Drainage Area Average Flow__.___ 30 Q 2 .—.._
Winter 7 Q 10 Summer 7 Q 10—.
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Golf Course
•
REQUEST NO: 9195 SITE NO: 1 DATE: 9/26/91
SOURCE: NRCD ACTION: EXISTING STREAMFLOW CONDITION:
STATION NUMBER: 0213828890 TYPE STATION: 20
STATION NAME: W F LINVILLE R TRIB NR LINVILLE, NC
LOCATION: AT HDWTRS AND 2.2 MI N OF LINVILLE, NC
LATITUDE: 360610 LONGITUDE: 815202
QUADRANGLE NUMBER: C11SE
COUNTY CODE: 011 STATE CODE: 37 DISTRICT CODE: 37
HYDROLOGIC UNIT CODE: 03050101 NRCD BASIN CODE: 030830
DRAINAGE AREA: 0.24
AVERAGE FLOW: 0.58 RANGE: cfs to cfs Percent [B]
7010 MIN FLOW: 0.09 RANGE: cfs to cfs Percent [B]
(SUMMER)
30Q2 MIN FLOW: 0.18 RANGE: cfs to cfs Percent [B]
7Q10 MIN FLOW: 0.12 RANGE: cfs to cfs Percent [B]
(WINTER)
7Q2 MIN FLOW: 0.14 RANGE: cfs to cfs Percent [B]
NOTES:
[A] Estimate is based on records collected at or near the site. The range
indicates approximate interval in which the actual value may lie
[B] Estimate is based entirely on runoff observed at nearby streams.
[C] Because of the probable degree of inaccuracy of the estimate only
a range is given.
[D] Approximately.
Streamflow Condition Codes [R] Regulated [N] Natural
****** These data are provisional pending approval by the Director,USGS ""***
REMARKS:
REQUESTOR--NOWELL
Data Index -- Entered by: AF
REQUEST NO: 9195 SITE NO: 2 DATE: 9/26/91
SOURCE: NRCD ACTION: EXISTING STREAMFLOW CONDITION:
STATION NUMBER: 0213828895 TYPE STATION: 20
STATION NAME: W F LINVILLE R TRIB AT MTH NR LINVILLE, NC
LOCATION: AT MTH AND 1.8 MI N OF LINVILLE, NC
LATITUDE: 360548 LONGITUDE: 815248
QUADRANGLE NUMBER: C11SW
COUNTY CODE: 011 STATE CODE: 37 DISTRICT CODE: 37
HYDROLOGIC UNIT CODE: 03050101 NRCD BASIN CODE: 030830
DRAINAGE AREA: 0.76
AVERAGE FLOW: 1.8 RANGE: cfs to cfs Percent [B]
7Q10 MIN FLOW: 0.28 RANGE: cfs to cfs Percent [ ]
(SUMMER)
30Q2 MIN FLOW: 0.63 RANGE: cfs to cfs Percent [ ]
7Q10 MIN FLOW: 0.46 RANGE: cfs to cfs Percent [ ]
(WINTER)
7Q2 MIN FLOW: 0.51 RANGE: cfs to cfs Percent [ ]
NOTES:
[A] Estimate is based on records collected at or near the site. The range
indicates approximate interval in which the actual value may lie
[B] Estimate is based entirely on runoff observed at nearby streams.
[C] Because of the probable degree of inaccuracy of the estimate only
a range is given.
[D] Approximately.
Streamflow Condition Codes [R] Regulated [N] Natural
****** These data are provisional pending approval by the Director,USGS ******
REMARKS:
REQUESTOR--NOWELL
Data Index -- Entered by: AF
State of North Carolina
Department of Environment, Health, and Natural Resources
Asheville Regional Office
James G. Martin, Governor
William W. Cobey, Jr., Secretary
DIVISION OF ENVIRONMENTAL: MANAGEMENT
WATER QUALITY SECTION
MEMORANDUM
TO:
THROUGH:
FROM:
SUBJECT:
May 21, 1991
Dale Overca. h , �uperv=. sor
NPDES Group
Forrest R. Wes
Water Quality R-': " `la:. Supei:v:i4Jor
Paul R. White, I. . E.
PR
Environmental En;.ineer
Ann B. Orr
Regional Manager
•
L CEIVED
MAY 3 1 1991
`EChNi`;.L SUPPORT BRA.
Linville Ridge Development_.
Permit No. NCOO624a3
Engineering Report: on Discharge Alternatives
Avery County
We have reviewed the engin-:ring report on Linville Ridge and
feel that it is a reasonably complete evaluation of the alternatives
as required by their permit. The permi. tee should be reminded that
the stricter limits pertaining to POD-5 and dissolved oxygen take
effect at the existing discharge point beginning July 1, 1993. If a
permit modification is desired reflecti.rv; a relocated discharge point,
this request should be made as soon as possible to allow ample time to
process the waste load allocation request for the proposed discharge
point, to process the permit modification, and to design, obtain
approval, and construct the required facilities.
If the permittee desires to construct. the required facilities to
meet the stricter effluent limitations at the existing discharge
point, it is likewise recommended that the process be initiated
immediately so that the necessary modificat'.ons will be in place well
ahead of time to assure proper operation pi-: or to the effective date
of the stricter limits.
If you would like to/discus<< th_.s fi,.rth-�r please call.
xc: Trevor Clements
Interchange Building. 59 Woodfin Place. A \heville, N.C. 28801 • Telephone 704251-tQ08
An Equal Opportunity Affirmative Action Entplovcr
DIVISION OF ENVIRONMENTAL MANAGEMENT
MEMORANDUM
May 10, 1991
TO: Dale Overcash
!L-/
THRU: Trevor Clements
Ruth Swanek i:[-
Carla Sanderson
FROM: Jacquelyn M. Nowellam
SUBJECT: Review of Discharge Alternatives Study for
Ridge Development Company
NPDES Permit No. NC0062413
Avery County
Linville
The Technical Support Branch has completed its review of the
discharge alternative study for the subject facility. The engineer-
ing report was an evaluation of the four nondischarge alternatives
listed in Condition G of the NPDES permit.
We concur with the engineering firm that the best alternative
for the Linville Ridge Development Company is "to pipe the discharge
:downstream to a location of positive 7Q10 flow" and to add a ter-
tiary sand filter to the plant. Our flow data indicate an old USGS
station (June 1984) on the UT West Fork Linville River with a summer
7Q10 flow of 0.1 cfs. However, because this station is nearly seven
years old, the flow information would need to be updated with a cur-
rent estimate when the facility requested relocation of the dis-
charge.
Please contact me if there are additional questions concerning
this matter.
CC: Roy Davis
Central Files
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J. CRAIG CRANSTON. P.E.
THOMAS H. ROBERTSON. P.E.
ELDRIDGE A. WHITEHURST, JR.. P.E.
Cranston, Robertson & Whitehurst, P.C.
ENGINEERS PLANNERS SURVEYORS
OLD ENGINE COMPANY NO. l POST OFFICE BOX
452 ELLIS STREET AUGUSTA. GEORGIA
TELEPHONE (404) 722.1588
TELECOPIER (404) 722-8379
April 3, 1991
Citul --.)" 4 AP0 Tsio
72-1- 6.1- As PAL.
RECE!VEDNT.AAWAY
oAMES B. CRANFORD. JR.. P.E.
APR ri GODEFROY. P.E.
LMAXWELL,111
BARBARA L PHIFER. P.E.
RANK PURNELL
PERMITS & ENGINE M. swANN. LS.
North Carolina Department of Environment,
Health & Natural Resources
Division of Environmental Management
512 North Salisbury Street
Raleigh, North Carolina 27611
RE: Linville Ridge Waste Water
Treatment Plant
Avery County, N.C.
Our File No. 90-268
Permit No. NC0062413
Gentlemen:
On July 2, 1990, you issued a new NPDES permit for the waste
water treatment facility which serves the clubhouse at the
Linville Ridge Development in Avery County, North Carolina.
Pursuant to Part III, Item D, we are submitting herewith
an Engineering Report evaluating non -discharge alternatives. On
behalf of the owner of the development, Linville Ridge
Development Company, we are transmitting two (2) copies of this
report in keeping with the requirement that such a report be pre-
pared and submitted within twelve months of the issue date of the
new permit.
We believe that the report is self-explanatory. However, if
you have any questions or wish to discuss the information
further, please do not hesitate to contact us.
Sincerely,
CRANSTON, ROBERTSON & WHITEHURST, P.C.
Eldridge A. Whitehurst, Jr. , P.E.
EAW/jk
cc: Mr. Michael H. Dilley, Vice President (3)
r
r
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L/NVILLE RIDGE DEVELOPMENT
WASTE WATER TREATMENT PLANT
DISCHARGE A L TERNA TI VES STUDY
AVERY COUNTY NORTH CAROUNA
An Engineering Report RECEav7
APR
PmITS & FNGINFFRIN(;
PREPARED FOR
LINVILLE RIDGE DEVELOPMENT COMPANY
`,`ttti11111/t!/r'f
,\`` C /.
SEAL •'
PREPARED BY
Cranston, Robertson & Whitehurst, P.C.
452 ELLIS STREET -- P.O. DRAWER 2546 -- AUGUSTA, GEORGIA 30901
Engineers --- Planners --- Surveyors
w
.afiiiMars
MMUILCINCN
MARCH 1991
J
LINV
ILLE RIDGE WASTE WATER TREATMENT PLANT DISCHARGE
ALTERNATIVES STUDY
1-V i1. 1 ;.) 1991
?PERMITS F FNaINFFRINC
PURPOSE
This repor
t has been prepared to present the results of a
study evaluating
nondischarge alternatives for the effluent from
the existing wast
e water treatment plant at Linville Ridge
ur ose of this study has been to determine
Development; The p p of the
whether
there is a feasible alternative to disposing
effluent from the treatment facility which is now discharged into
the West Fork of
the Linville River immediately adjacent to the
plant.
GENERAL
Linville Ridge Development is a second home, recreational
development locat
ed in Avery County, North Carolina. The
development is comprised of some 1,500 acres of land situated
approximately two
miles north of Linville, North Carolina on the
west side of Highway hwa 105 at its intersection with Highway 184.
The location is mo
re clearly shown on Figure 1. Amenities to the
degolf course, swimming pool complex, tennis
development inclu a 9
courts and cl
ubhouse facilities. While there are few, if any,
year round resident
sthere will be some 450 homes and/or multi-
,
family units upon full build out. Waste water for all
residential units
is accomplished by means of septic tank and
ground absorption systems.
grill 1983 a and pro shop facility was constructed at
the golf course.
Waste water from this facility was handled by
1
I
1
1
1
i
1
1
1
I
1
means of a septic tank and ground absorption system permitted by
the Avery County Health Department. Then, in 1985 the clubhouse
was constructed to house dining rooms, lounges, locker room
facilities, golf carts, and sales and accounting offices. This
facility has some 35,000 square feet of space. The estimated
waste production from the facility when fully utilized is some
12,600 gallons per day.
WASTE WATER TREATMENT PLANT
On August 21, 1985 the North Carolina Department of Natural
Resources and Community Development issued an National Pollutant
Discharge Elimination System (NPDES) permit for a 15,000 gallon
per day discharge into the West Fork of the Linville River for a
plant to serve the clubhouse. Cranston, Robertson & Whitehurst,
P.C. prepared plans for a 0.015 MGD plant at the proposed site on
the Linville Ridge property, and an "authorization to construct"
the plant was issued by NRCD on April 28, 1986. On May 21, 1986,
a 0.015 MGD Modular Extended Aeration Waste Water Treatment Plant
was put into service. This plant has operated since that time
with effluent discharges ranging from 1,000 gallons per day in
the winter to 8,000 gallons per day in the summer months.
ALTERNATIVE STUDY REQUIREMENTS
When Linville Ridge Development Company applied for a
renewal to its NPDES Discharge Permit, a new permit was issued on
July 2, 1990. As part of this new permit a requirement was added
stating that "within 12 months of the issue date of this permit,
the permit holder shall submit an engineering report evaluating
nondischarge alternatives. As a minimum, the following
i
alternatives should be addressed: (1) moving discharge point to a
positive 7Q10 flow stream, (2) subsurface disposal, (3) spray
irrigation, and (4) connecting to an existing or imminent
sewerage system."
It should be noted that the permit also now places stricter
limits on effluent quality after 1993. If no alternative to the
current discharge can be shown to be a viable alternative, a
modification will still have to be made to the plant to improve
effluent quality.
ALTERNATIVES
1. Relocating Discharge Point:
The nearest gauging station on the Linville River is
located in the Community of Linville, North Carolina, some
two miles south of the Development. The seven day, ten year
(7Q10) flow at this location is 2.1 cfs as reported by the
United States Geologic Survey (USGS) office in Raleigh,
North Carolina. The 7Q10 flow is a statistical calculation
of the lowest average flow at a location for any seven days
during a ten year period. Since the station is located
just upstream from the confluence of the West Fork of the
Linville River and the main branch of the Linville River,
the low flow based upon measurements at the gauging station
actually does not account for the West Fork. However, if
one assumes that the characteristics of the drainage basin
of the West Fork
a 7Q10 can be
drainage areas.
treatment plant
are similiar to those for the main channel,
extrapolated based upon a comparison of
By doing this the 7Q10 at the current
site behind the 18th green is 0.015 cfs.
1
1
1
1
1
1
i
The USGS considers any flow rate below 0.05 to be 0 flow.
In order to determine at what point downstream from the
current treatment plant discharge site on the West Fork that
the drainage basin would be large enough to provide a
positive 7Q10 flow, a trial and error study was done
utilizing an existing 1" = 200' topographic map of Linville
Ridge with a five foot contour interval. Points along the
stream were selected and each drainage basin area
calculated. Each was then compared to the drainage basin
in
for the gauging station in Linville on a prorated basis. It
was determined that the closest location downstream which
would provide a positive 7Q10 flow of 0.055 is just
downstream from the #10 green. This location is a distance
of some 2,000' from the current discharge point as shown on
Figure 2.
The work required to pipe the effluent discharge from
the treatment plant to a new location downstream below the
loth green would involve installing 6" PVC pipe along the
edge of the 18th and then loth fairways. It is anticipated
that no manholes would be used and that cleanouts located at
bend points and at 400' intervals would be installed. The
estimated cost to install such a line is $20,000.00.
It should be noted here that an additional cost which
would be incurred with this alternative involves the
addition of a tertiary filter at the existing treatment
plant. The use of the piping alternative would mean that
the additional, more restrictive limits on the quality of
the effluent would come into play as previously noted. The
modification of the existing plant to incorporate a tertiary
sand filter would cost in the neighborhood of $20,000.00.
2. Subsurface Disposal:
During the early planning for the clubhouse and
studying of possible methods by which to treat the waste
generated by the facilities, consideration was given to
handling the waste by means of a septic tank and absorption
field. Based on the type of soils generally found on the
property of Linville Ridge and the amount of flow estimated
per day, it was preliminarily determined that an absorption
field
There
golf
of approximately 17,000 S. F.
was
would be required.
no location in the vicinity of the clubhouse
course which could provide the required area but
and
was
not too close to streams, wells or other facilities not
suitable for close proximity to an absorption field or that
was not thought to have shallow rock and/or marginal soils
present. Consideration was given to piping the sewage down
the face of the steep escarpment below the clubhouse to
other undeveloped property. However no areas were found
below the clubhouse which appeared to be flat enough, devoid
of rock, or far enough away from water courses to satisfy
the requirements for such a large system.
With the current development of virtually the entire
area of Flat Top Mountain above the escarpment in the
vicinity of the clubhouse, and the development of a good
deal of the lands below the escarpment, there is even less
chance of finding an adequate site now. A field
reconnaissance of the the property and review of existing
topographic maps has failed to yield any promising sites.
This does not even consider the fact that in most cases for
marginal soils, a backup site is also required.
In summary, there does not appear to be an appropriate
location on undeveloped Linville Ridge property for a large
enough absorption field for subsurface disposal of the plant
effluent which would meet current North Carolina criteria
•
for such facilities.
3. Spray Irrigation:
Spray irrigation is a method of disposal which involves
the collection of the effluent leaving the treatment plant
and the spraying of this effluent upon suitable vegetated
lands. In many locations, spray irrigation is well suited
for use with a golf course facility because the existing
irrigation lines can be utilized for the operations, and the
materials in the effluent are good for promoting the growth
of grass and other vegetation.
The requirements to be met in utilizing spray
irrigiation to dispose of treatment plant effluent are
enforced by the North Carolina Department of Environment,
Health & Natural Resources, Division of Environmental
Management. In order to comply with the regulations the
Linville system would need the following additional
facilities:
a. An aerated flow equalization facility at the existing
plant with a capacity of 25% of the plant design flow.
b. Modification of the existing plant so as to provide
duplicate treatment units in the plant such that in the
event that one set of units fails the other one will be
able to continue operation.
c. The installation of a tertiary sand filter to reduce
the total suspended solids to meet more stringent
requirements required for spray irrigation.
d. A five day lined detention pond in which the effluent
• would be stored before spray application.
e. A pumping facility to pump the effluent from the five
day pond into the golf course irrigation system and
through the sprinkler system.
f. An automatically activited standby power source such as
a disel operated generator to provide power in the
event of a power outage and to prevent improperly
treated waste water from entering the five day
detention pond.
Other considerations in utilizing spray irrigation
include a requirement that spraying only occur between 11:00
p.m.
and 3 hours prior to the daily opening of the course;
a 100' vegetative buffer zone between the edge of spray
influence and the nearest dwelling; signs posted at the pro
shop stating the course is irrigated with treated waste
water; a certified operator on call 24 hours per day; and a
rate of application not exceeding 1 and 3/4 inch per week
on the area being sprayed.
We have looked at the driving range irrigation system
and believe that the effluent could be disposed of by
utilizing only this area. Several valves would need to be
installed to isolate the irrigation lines in the driving
range from the rest of the system. The cost of modifying
the existing plant as required to utilize spray irrigation
is very site specific but a preliminary cost of $100,000.00
is estimated.
4. Connecting to Existing or Imminent Sewage System:
The utilization of an existing system for the effluent
from' the Linville Ridge plant has been considered by
identifying the closest plants to Linville Ridge and by
contacting the owner and/or operator to determine whether
there is sufficient capacity and whether the plant would be
willing to take on additional flow. Furthermore an estimate
of costs to get the effluent to the plant has been made
where applicable.
Existing plants are located at Sugar Mountain
Development north of Linville Ridge, at Grandfather Mountain
Development across Highway 105 to the east of Linville Ridge
and the Community of Linville south of Linville Ridge. No
imminent plants are known at this time.
The Sugar Mountain waste water facility is located
approximately 2 miles by road measurement from the Linville
Ridge Treatment Plant. The plant has a current capacity of
0.5 MGD (as of August 1, 1990), and it is operating at
approximately 3/4 capacity. We understand that the owner
also has plans to request an increase in the discharge
permit to increase the plant capacity an additional 0.5
MGD.
This plant would probably take the Linville Ridge
discharge if it could be piped to the plant. This would
require a pumping station, a holding pond, emergency backup
power source, and the installation of a force main over the
crest of Flat Top Mountain into the Sugar Mountain Valley.
Furthermore, the installation of the force main could
require the obtaining of easements from private individuals
as well as the developer of Sugar Mountain in order to reach
the system flowing into the plant.
could be obtained, this scheme would cost
estimate of some $125,000.00 or more.
The Grandfather Mountain treatment plant is located
approximately one mile from the Linville Ridge plant and has
a capacity of 0.07 MGD (as of August 1, 1990). The plant is
currently operating at over 90% capacity, and it is expected
that continued growth at the Grandfather Mountain
Development will take up this remaining capacity. Thus, it
is believed that the Grandfather Mountain treatment facility
is not a viable alternative to handling the Linville Ridge
clubhouse effluent.
The Community of Linville has a waste water treatment
facility very near the gauging station on the Linville
River. This plant has the capacity of 0.5 MGD and is
currently operating at near capacity (as of August 1, 1990).
The plant is located some 2.8 miles from the Linville Ridge
facility
Even if
the
easement
a preliminary
and the cost of transporting the effluent to this
plant would be very high even if excess capacity was
available.
SUMMARY:
It is apparent that the utilization of an existing off -site
facility for the treatment and disposal of the Linville Ridge
Clubhouse Plant effluent is not a viable alternative because the
lack of capacity or the expense in accomplishing the
transportation of the effluent. Furthermore for the one plant
which might be utilized there are no guarantees that necessary
easements could be obtained. Unfortunately Linville Ridge does
not have'the right of condemnation which municipalities enjoy to
solve such problems.
The option of utilizing subsurface disposal is not
considered a viable alternative because of the marginal nature of
the soils for use in absorption fields; the large amount of land
required for the primary field and an alternate field given the
number of small streams and springs on the property, especially
in the undeveloped areas; and the lack of any relatively flat
areas in the remainder of undeveloped property which lend
themselves to such a large absorption field.
It would appear that the use of spray irrigation or the
piping of the effluent downstream to a point of positive 7Q10
flow would be workable alternatives. However, spray irrigation
cannot always be accomplished on frozen grounds or in periods of
high rains, both of which are likely in this locality. Such
conditions would cause an effluence discharge into the West Fork
of the Linville River anyway. Thus, the best alternative appears
to be to pipe the discharge downstream to a location of positive
7Q10 flow. It is of note that the requirement to add a tertiary
sand filter to the plant would be necessary for both the spray
irrigation scheme and the downstream piping scheme.
In order to meet the requirements of the NPDES Permit in
1993, the planning and design of a tertiary filter and piping
downstream are recommended.