NC0001899_Lagoon Closure Memo_20120622

Ani
NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Charles Wakild, P. E. Dee Freeman
Governor Director Secretary
MEMORANDUM
TO: Aquifer Protection Section Staff
Interested Parties
FROM: Ted L. Bush, Jr., Deputy Direct
Division of Water Quality
June 22,2012
1/42
SUBJECT: Guidelines for the Closure ofpeFmitted Wastewater Ponds and Lagoons
Purpose
The purpose of these guidelines is to provide a course of action for the closure of permitted Non -Discharge
wastewater treatment ponds, storage ponds, or lagoons. According to G.S. 143-215.1, construction and operation
of any sewer system, treatment works or disposal system within the state of North Carolina requires a permit. 15A
NCAC 2T .0105(j) requires that waste treatment systems (or parts thereof, such as lagoons, storage ponds, etc.)
authorized by a permit must be properly closed before that permit (or parts thereof) can become inactive. These
guidelines provide clarification as to what "properly closed" entails.
While each structure must be considered for its unique circumstances, the Aquifer Protection Section (APS) has
outlined general procedures (attached) to be used for closure of wastewater treatment ponds and lagoons permitted
by the Section. These guidelines are not intended to address lagoons used for animal waste and their associated
facilities, or ponds used for the storage of coal combustion by-products. However, it is the intent of APS to require
similar close out procedures for comparable scenarios in coordination with other permitting agencies such as the
Surface Water Protection, or other interested parties. These guidelines supersede Guidelines for the Closure of
Treatment Ponds and Lagoons implemented August 18, 2003.
Closure Approval
The closure of a Non -Discharge permitted wastewater treatment or storage pond or lagoon should begin with
notification by the permittee to the APS. This should include a request to close a specific permitted pond or lagoon,
and an indication whether the permit should be modified or rescinded. APS will make available the attached
closure checklist/ guidelines to the permittee, who should propose a closure plan based on the attached guidelines.
This closure plan should generally include or describe the following (see next page):
1617 Mail Service Center, Raleigh. North Carolina 27699-1617
Location: 512 N. Salisbury St. Raleigh, North Carolina 27604
Phone: [phone] FAX: [phone]
Internet: www.ncwateraualitv.orq
NorthCarolina
Naturally
An Equal Opportunity 1 Aflumative Action Employer

Guidelines for the Closure of Permitted Wastewater Treatment Storage Ponds and Lagoons
• Checklist with chosen options and requirements indicated (Attachment A, page A-1)
• Historical use of impoundment (include all waste streams) and current status
• Future plan for site
• Disposal options for wastewater
• Disposal options for sludge
• Sludge disposal location(s)
• Sampling plan for wastewater and/or sludge
Once the permittee submits their closure plan, a preliminary inspection will be conducted and an inspection report
with additional closure instructions (if needed) will be presented to the permittee. The permittee will then submit a
final closure report documenting their closure procedure. The final closure report may include the following:
• Sampling results
• Volume of sludge disposed and location
• Companies/Contractors involved
• Final Certifications
The Regional Office will conduct a final inspection and present the results of that inspection to the permittee, along
with their recommendation to the APS Central Office for approval or disapproval of a permit modification or
rescission.
Applicable Regulations
Regulations that may be applicable to the abandonment of Non -Discharge permitted ponds and lagoons are listed
below. These guidelines do not go into the detailed requirements of the regulation listed. However, each bullet
summarizes how the regulation may be applicable to the action requested.
• Title 15A NCAC 2L, Classifications and Water Quality Standards Applicable To The Groundwaters of
North Carolina. This regulation requires that groundwaters must be protected to a level of quality at least
as high as that required under standards established in Section .0202 of that Rule.
• Title 15A NCAC 2T, Waste Not Discharged to Surface Waters. This rule establishes requirements that are
protective of surface water and groundwater standards for systems that treat, store, transport, and dispose
of residuals and do not discharge waste to surface waters.
Other pertinent standards and regulations may be found in the Department of Environmental and Natural Resources
(DENR) Division of Land Resources (DLR) regulations pertaining to Sedimentation and Erosion Control and Dam
Safety, the DENR Division of Waste Management (DWM) regulations pertaining to the disposal of wastes and
sludge, and the Department of Transportation (DOT) regulations pertaining to transportation of materials on public
highways.
cc: Surface Water Protection (Matt Matthews)
Attachments
A. Checklist and Instruction Items
B. Flow Charts
Page 2

ATTACHMENT A

ATTACHMENT A CLOSURE OF PERMITTED WASTEWATER PONDS AND LAGOONS
Checklist and Instruction Items
The purpose of the following checklist and instruction items is to aid in the development of a closure plan for
a permitted Non -Discharge wastewater pond or lagoon to be submitted to the appropriate APS Regional
office for approval.
The following checklist allows the applicant to identify the type of lagoon to be closed, and the preferred closure
and disposal options. The selected options include references to instruction items (e.g. Item A) found on
subsequent pages of this attachment. The instruction items describe what steps are expected to be complete prior to
approval of the closure plan, including expected sampling and monitoring, and final certifications of complete
closure. Note that the following steps are not all inclusive, as each site is unique and may have varying site
conditions. In addition, flowcharts (Attachment B) have been provided as an alternate to the instructional Items A-
H. These charts contain the same information, but give a visual representation of the closure process. For
questions, contact the approving APS Regional Supervisor. Please check all items below that apply and submit a
completed copy with the lagoon closure plan.
Type of Pond or Lagoon System
a. Primary and Secondary Biological Wastewater Lagoon Systems (examples: food processing treatment
lagoons, municipal treatment systems without pretreatment programs, neighborhood treatment systems).
b. Primary and Secondary Industrial Wastewater Lagoon Systems(examples: non-food type industrial
treatment systems, municipal treatment systems with pretreatment program).
c. Tertiary Wastewater Pond Systems ( examples: wastewater biological treatment systems with tertiary
treatment to include infiltration disposal pond systems, effluent polishing pond systems).
II. Closure Options — Structure
a. Conversion to Non -Wastewater Pond — Change of Use (Item B)
b. Complete or partial removal of structure (Items G)
c. Site Reclamation (Item F and H)
III. Final Liquid and Solid Content Disposal Options
a. Wastewater Disposal to Onsite Permitted Field (Item A)
b. Wastewater Disposal through Pump and Haul (Item A)
c. Sludge Disposal to Permitted Site (Items C and D)
d. Sludge Left in Place (Items C and E)
IV. Sampling and Monitoring Requirements
a. Wastewater Sampling Required (Items A and B)
b. Soil and Sludge Sampling Required (Items C and F)
c. Groundwater Monitoring Required (Item G)
V. Final Certification Required for Closure Activities, as required in Item I.
a. Structural Deconstruction (Professional Engineer or Hydrogeologist)
b. Wastewater Disposal (Facility ORC)
c. Sludge Disposal (ORC / Licensed Sludge Land Application Contractor)
d. Other (Explain: )
A-1
Attachment A June 22, 2012

ATTACHMENT A CLOSURE OF PERMITTED WASTEWATER PONDS AND LAGOONS
Item A. Wastewater Sampline, Analysis, and Disposal
1. Pond samples require a composite sampling technique. Samples should be composited from several
locations. An adequate number of representative and composite samples should be taken and developed
respectively.
2. For permitted disposal sites, sample and analyze wastewater in accordance with permit conditions. In the
absence of permit specified monitoring, sample for the following parameters:
a. Fecal coliform bacteria, chlorine residuals (if used as disinfectant), total nitrogen, BODS, TSS, pH.
b. Other parameters may be required based on waste streams, as directed by the APS Regional
Supervisor.
3. All wastewater samples must be analyzed by a DWQ-certified laboratory.
4. Once the wastewater is sampled, the pond/lagoon can be dewatered to a permitted disposal site (uniform
application of wastewater) or through a pump and haul permit.
5. Remove or plug all inflow and outflow piping, etc to the pond/lagoon
Item B. Conversion to Non -Wastewater Pond (Tertiary Treatment Ponds Only)
6. Determine pond liquid volume (if water accumulates after complete disposal per Item A, Wastewater
Sampling, Analysis, and Disposal).
7. If some sludge remains, sludge can be left in place, in accordance with Item E#23 below. Otherwise,
remove all residuals and dispose of properly per Item D, Sludge and Soil Disposal.
8. Disinfect and/or treat pond to meet Item B#11 requirements below.
9. Sample pond (see Item A, Wastewater Sampling, Analysis, and Disposal)
10. No pond discharge is allowed to surface water without prior approval from an appropriate Surface Water
Section Regional Office. Note that pond discharge to class SA waters is not allowable.
11. All discharges must meet water quality standards applicable to receiving stream classification or per limits
provided by DWQ when water quality stream standards for monitored parameters are not defined.
Item C. Soil and Sludge Analysis
12. All soil and sludge samples require a composite sampling technique. An adequate number of
representative and composite samples should be taken and developed respectively. Thickness of sludge or
soil and surface acreage should be considered. Example: one composite sample per acre foot.
13. All soil and sludge samples must be analyzed by a DWQ-certified laboratory.
14. For biological wastewater lagoons systems and tertiary wastewater pond systems, soil or sludge shall be
sampled for:
a. Pathogen and Vector Attraction Reductions. Testing should be done per 15A NCAC 02T .1100. If
project concerns only a tertiary pond, and pond sediments/sludge meets Class A pathogen
reduction requirements (maximum of 1000 fecal coliform bacteria colonies per gram of total
solids), additional characterization for pH, metals, nutrients, and solids as stated in 14.b and 14.c
(below) may not be required, as determined on a case by case basis.
b. Arsenic, cadmium, chromium, copper, lead, mercury, molybdenum, nickel, selenium, zinc, TKN,
ammonia nitrogen, nitrate/nitrite, nitrogen, phosphorus, sodium, calcium, magnesium (mg/kg dry
wt basis), percent total solids and pH.
c. Other parameters may be required based on waste streams, as directed by the APS Regional
Supervisor.
A-2
Attachment A June 22, 2012

ATTACHMENT A CLOSURE OF PERMITTED WASTEWATER PONDS AND LAGOONS
15. For industrial wastewater lagoon systems, this should be the same as biological wastewater lagoon system
sampling plus site -specific parameters and hazardous characterization to include, but not limited to, TCLP,
ignitability, corrosivity and reactivity.
16. If the sludge or soil samples are:
a. Required to be analyzed for hazardous characteristics and results exceed hazardous characteristics
regulatory limits, the material needs to be removed and reported to and managed in accordance
with the Hazardous Waste Section in the Division of Waste Management.
b. Not required to be analyzed for hazardous characteristics or results do not exceed the hazardous
characteristics regulatory limits, the soil can be left in place if the following conditions are met :
i. Total concentrations of contaminants in soil do not exceed protection of groundwater soil
concentrations for North Carolina based on 2L standards, as calculated using theTransport
Model for Calculation of Soil -to -Groundwater Concentrations from the USEPA 1996 Soil
Screening Guidance document. (The EPA Transport model can be found in the "Soil
Remediation Goals Table" at http://portal.ncdenr.org/web/wm/sf/ihs/ihsguide or the "2L,
MCL, and Soil Screening Levels Table" at
http://portal.ncdenr.org/web/wm/hw/technical/guidance.)
ii. Total concentrations of contaminants in the soil exceed protection of groundwater soil
concentrations for North Carolina, but results do not exceed naturally -occurring
background concentrations,
iii. A more stringent soil clean-up level is not necessary due to site specific conditions as
determined by the Division.
For sludge left in place, see Item E, Sludge Left in Place. For sludge disposal, see Item D, Sludge
and Soil Disposal.
c. Not required to be analyzed for hazardous characteristics or results do not exceed hazardous
characteristics regulatory limits, but total concentration results exceed corresponding protection of
groundwater soil concentrations for North Carolina as calculated using the Transport Model from
the USEPA 1996 Soil Screening Guidance document described in 16(b)(i), soil and sludge must be
disposed of according to Item D, Sludge and Soil Disposal. For soils that exceed protection of
groundwater levels, Item G, Groundwater Post Closure Monitoring, must also be considered.
17. For ponds or lagoon bottoms that intercept groundwater, Regional Offices will determine what type of
sampling is required for the remaining contents on a case by case basis.
Item D. Sludge and Soil Disposal
18. Measure surface area and depth of sludge and soil (if required) to determine disposal volume
19. Sample sludge and soil (if required) for permitted disposal option including pathogen and vector attraction
reduction verification (see Item C, Soil and Sludge Analysis)
20. If a tertiary pond and sludge/sediments meet Class A pathogen and vector attraction reduction
requirements, sludge/sediments can be land applied uniformly on site without sludge permitting action
(additional sludge or soil characterization may not be required, as determined on a case by case basis).
21. If sludge or soil does not meet Class A pathogen and vector attraction reduction requirements,
sludge/sediments may require a permit modification to land apply.
22. Pathogen and vector attraction reduction testing will not be required if sludge or soil is taken to a permitted
compost or another treatment facility for further stabilization.
A-3
Attachment A June 22, 2012

ATTACHMENT A CLOSURE OF PERMITTED WASTEWATER PONDS AND LAGOONS
Item E. Sludge Left in Place
23. For closure purposes, the Division of Water Quality considers it practical to remove sludge content from
structures. The Division will evaluate the applicability of leaving any remaining volume of sludge content
in the structure on a case by case basis. Sufficient technical justification shall be provided to support such
recommendation.
Item F. Liner Demolition/Disposal
24. If a synthetic liner is present, remove synthetic liner, scarify/rip/disk underlying material in cases where
there is no potential benefit for reuse of the structure based on projected future site use.
a. If there are no historical problems with the lagoon (documented seepage, etc.) and the liner is intact
after dewatering with no visible indications of seepage, soil sampling may still be required on a
case -by -case basis.
b. If liner and/or lagoon issues are documented, the soil material under the synthetic liner should be
sampled according to Item C, Soil and Sludge Analysis.
25. If clay liner is present, scarify/rip/disk and/or remove and reuse as cap if filling. If the liner is natural clay,
sampling may be required on a case by case basis if the following conditions are not met:
a. Based on existing groundwater monitoring data, no groundwater violations are present,
b. Domestic wastewater systems only,
c. Surficial layer of earthen material (top 6" — 12") removed , and
d. All sludge removed and the remaining material is only soil and not co -mingled soil/sludge.
26. If the clay liner does not meet the conditions in 425 above, the clay liner should be sampled according to
Item C, Soil and Sludge Analysis.
27. If a pond or lagoon does not have a liner, the underlying soil should be sampled according to Item C, Soil
and Sludge Analysis.
Item G. Groundwater Post Closure Monitoring
28. For facilities with no historic groundwater monitoring, monitoring may be required based on post closure
soil sample results. Contact Regional Office for directions. If groundwater monitoring is not required,
permittee can petition the Division for rescission once the site is reclaimed.
29. For ponds or lagoons with historic groundwater monitoring and no groundwater violations were detected,
no further groundwater monitoring will be required, as recommended by the Regional Office based on
existing data.
30. For ponds or lagoons with historic groundwater monitoring and/or 15A NCAC 2L standards were
exceeded, the following actions would be required:
a. Maintain permit with limited actions as recommended by the Regional Office (e.g. annual
groundwater monitoring and reporting).
b. Continue groundwater monitoring as permitted for a minimum of three sampling events.
i. If there are no further groundwater exceedances detected or exceedances show a trend of
lowering toward groundwater standards, the permittee could petition the Division for
permit rescission.
ii. If groundwater exceedances continue at the same level, continued monitoring and or site
evaluation would be required at the Regional Office Supervisor's discretion.
c. In lieu of groundwater monitoring, the Permittee may provide predictive calculations, acceptable to
the Director, to demonstrate groundwater standards can be met at the property boundary.
A-4
Attachment A June 22, 2012

ATTACHMENT A CLOSURE OF PERMITTED WASTEWATER PONDS AND LAGOONS
Item H. Berms/Laaoon Walls and Site Reclamation*
31. In cases where retention of municipal structures provides no value based on projected future site use, it is
recommended that minimal demolition be performed to breach or remove sidewalls (dependent on the size)
when the liner is demolished. Minimal demolition may be considered feasible in cases where retention of
the structure or a portion thereof poses minimal risks based on conditions such as low population densities
of surrounding areas, low hazard environment, low probability of encroaching development, etc.
32. For privately owned and higher risk municipal structures, more extensive structure demolition is
recommended to include, but not be limited to, removal of berms/dike walls and general grading of project
site.
33. If structure is completely constructed at or below grade, fill with clean material (partial or complete,
depending on size) and/or grade site to minimize any hazards posed by existing conditions.
34. If structure is finished in the groundwater table, see Item C # 17.
35. Stabilize the site with vegetation. Establishment of trees, grasses, and other viable cover crops should be
considered to assist site stabilization and with removing any remaining nutrients.
*Recognize the added value of planned reclamation efforts. Reclamation activities incorporating created artificial
wetland systems, planted trees, and other pro -active actions viewed as either mitigation efforts or secondary
environmental protection measures may assist with enabling the closure project to qualify for recognition and
benefit from other environmental programs, such as those offered through conservation easements.
Item I. Final Certifications
36. For deconstruction including berm removal, berm breaching, or liner destruction, submit a letter certified
by the overseeing professional engineer that action was taken according to the approved plan, as well as all
local and state regulations.
37. For wastewater disposal, submit a copy of the monitoring report that documents lagoon wastewater disposal
activities, certified by the facility ORC.
38. For sludge disposal, submit a copy of the records documenting lagoon sludge disposal, certified by the
licensed sludge land application contractor if land applied. If sludge was disposed of in a landfill, records
from the receiving facility shall be provided.
39. Sampling results from any post -closure sampling conducted at the facility to document proper removal of
sludge in accordance with the approved closure plan shall be submitted.
40. Photos of closure activities documenting conditions prior to initiating closure, closure activities, and post -
closure conditions are recommended, but not required.
41. Other.
A-5
Attachment A June 22, 2012

ATTACHMENT B
The following flowcharts are a visual alternate to the information provided in Instructional
Items A-H in Attachment A. The checklist provided in Attachment A must still be
completed, whether the Instruction Items or flowcharts are used. Final certification
requirements are only found in Item I in Attachment A.

Attachment B — Closure of Permitted Wastewater Ponds and Lagoons
Flow Chart 1 — Wastewater Sampling and Disposals
START HERE
Does the site
have permit
specific
monitoring?
NO
YES
[Using an adequate number Jr-
representative composite
samples, test for fecal coliform
bacteria, chlorine residuals (if
used as disinfectant), total
nitrogen, BOD5, TSS, and pH.
Other parameters may be
required by Regional Office
based on waste streams.
Samples should be
composited from several
locations. All samples must
be analyzed by a DWQ-
certified laboratory.
•
y
Dewater po d/lagoon to
permitted disposal site or
through a pump and haul permit
issued by DWQ.
Remove or plug all inflow and
outflow piping.
If you ave a
tertiary pond,
do you want to
convert to non -
wastewater?
NO
Does sludge
remain?
NO
4
Sample lagoon wastewater in
accordance with the permit
conditions.
•
1
Proceed to Flow Chart 3 — Liner
Demolition and Disposal.
YES
YES
iIf water accumulates after disposal,
determine pond liquid volume and
disinfect/treat pond (if necessary) to meet
water quality standards applicable to
receiving stream classification or per limits
provided by DWQ when water quality
stream standards for monitored remetsrs are not defined. Sample as in
previous step. END If sludge remains,
proceed to Flow Chart 2 — Sludge
Analysis and Disposal.
4 Proceed to Flow Chart 2 — Sludge Analysis
and Disposal.
'No pond discharge is allowed to surface water without prior approval from an appropriate Surface Water Section Regional Office. All discharges
must meet water quality standards applicable to receiving stream classification or per limits provided by the Division of Water Quality when water
quality standards for monitored parameters are not defined. Pond discharges to class SA waters is NOT allowable.
Attachment B1 June 22, 2012

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Attachment B — Closure of Permitted Wastewater Ponds and Lagoons
Flow Chart 3 — Liner Demolition and Disposals
CONTINUED FROM FLOW CHART 1 — WASTEWATER SAMPLING, ANALYSIS, AND DISPOSAL OR
FLOW CHART 2 — SLUDGE ANALYSIS AND DISPOSAL
l
Scary/rip/ disk and/or
remove and reuse as
cap if filling.
Are all of the
following true?
a. Groundwater
sampling has been
documented and no
groundwater
violations are
present.
b. The system is
domestic waste -
water only.
c. The surficial layer of
earthen material
was removed.
d. No residuals
remain.
YES
Proceed to Flow Chart 6 —
Site Reclamation.
Soil sampling is
required.
Proceed to Flow
Chart 4.
l
e
NO
Soil sampling is required.
Proceed to Flow Chart 4 —
Soil Analysis and
Disposal.
Remo e liner,
scarify/ 'p/ disk
underlying material in
cases where there is no
potential benefit for
reuse of the structure
based on projected
future site use.
Historical
problems or
damaged
liner?
Soil sampling may be required
on a case -by -case basis.
Proceed to Flow Chart 5 —
Groundwater Post Closure
Monitoring.
For closure purposes, the DWQ considers it practical to remove sludge content from structures. DWQ will evaluate the applicability of leaving any
remaining volume of sludge content in the structure on a case -by -case basis. Sufficient technical justification shall be provided to support
recommendation.
Attachment 83
June 22, 2012

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naturally occurring soil background concentrations, then they are not considered an exceetlance.

Attachment B — Closure of Permitted Wastewater Ponds and Lagoons
Flow Chart 5 — Groundwater Post Closure Monitoring
CONTINUED FROM
FLOW CHART 2 — SLUDGE ANALYSIS AND DISPOSAL,
FLOW CHART 3 — LINER DEMOLITION AND DISPOSAL, OR
FLOW CHART 4 — SOIL ANALYSIS AND DISPOSAL
f
Has there
been historic
groun water
monit ring?
YES
Sampling of
wells indicate
groundwater
violations?
YES
V
Maintain permit with limited actions.
Continue groundwater monitoring as
permitted for m'nimum of three
sampling events.
J
After minimum of
three sampling
events, are
groundwater
violations detected
or exceedances
not showing a
lowering trend?
YES
1
Continue monitonng on a schedule
set by DWQ Regional Office
Supervisor.
NO
NO
0
Is grou dwater
moni oring
required?
YES
V
Contact DWQ Regional Office to
approve well locations before
installation.
No further groundwater monitoring
is required . Proceed to Flow
Chart 6 — Site Reclamation.
NO
Proceed to Flow Chart 6 —
Site Reclamation.
V
•
In lieu of groundwater monitor ng, predictive calculations,
acceptable to the Director, can be submitted to demonstrate
groundwater standards can be met at the property
boundary. Proceed to Flow Chart 6 — Site Reclamation.
Proceed to Flow Chart 6 — Site
Reclamation.
Attachment B5
June 22, 2012

Attachment B — Closure of Permitted Wastewater Ponds and Lagoons
Flow Chart 6 — Site Reclamation)
CONTINUED FROM FLOW CHART 3 — LINER DEMOLITION AND DISPOSAL OR
FLOW CHART 5 — GROUNDWATER POST CLOSURE MONITORING
YES
Berms/Lagoon Walls'
Is the structure
privately owned
or high risk
municipal?
NO
Is the s ructure
comp etely
constructed at or
below rade?
NO
Is the s ructure
finished in the
groundwater
table?
YES
l
Contact DWQ Regional Office to
determine what type of sampling
will be required. Then, proceed
` to appropriate Flow Chart .
YES
/ Fill with clean material and/or
_1(\\grade site. Stabilize the site
with vegetation. END
NO
Recommended more extensive structure demolition
(e.g. removal of berms/dike walls, general grading,
etc.). Stabilize the site with vegetation. END /
Recognize the added value of planned reclamation efforts. Reclamation activities incorporating created artificial wetland systems, planted trees, and other pro-
active actions viewed as either mitigation efforts or secondary environmental protection measures may assist with enabling the closure project to qualify for
recognition and benefit from other environmental programs, such as those offered through conservation easements.
z In cases where retention of municipal structures provides no value based on projected future site use, it is recommended that minimal demolition be performed to
breach or remove sidewalls (dependent on the size) when the liner is demolished. Minimal demolition may be considered feasible in cases where retention of the
structure or a portion thereof poses minimal risks based on conditions such os low population densities of surrounding areas, low hazard environment low
probability of encroaching development, etc.
Attachment B6 June 22, 2012