WQ0022810_More Information (Requested)_20220912

ROY COOPER
Governor
ELIZABETH S. BISER
Secretary
RICHARD E. ROGERS,]R.
Director
NORTH CAROLINA
Environmental Quality
September 13, 2022
ANTHONY AND ALLISON LAMPURI — OWNERS
808 MODENA DRIVE
CARY, NORTH CAROLINA 27513
Subject: Application No. WQ0022810
Additional Information Request
166 Decmocracy Pl. SFR
Single -Family Residence
Wastewater Irrigation System
Chatham County
Dear Mr. and Mrs. Lampuri:
Division of Water Resources' Central and Regional staff has reviewed the application package
received June 23, 2022. However, additional information is required before the review may be completed.
Please address the items on the attached pages no later than the close of business on October 13, 2022.
Please be aware that you are responsible for meeting all requirements set forth in North Carolina
rules and regulations. Any oversights that occurred in the review of the subject application package are
still the Applicant's responsibility. In addition, any omissions made in responding to the outstanding items
in Sections A through Q, or failure to provide the additional information on or before the above requested
date may result in your application being returned as incomplete pursuant to 15A NCAC 02T .0107(e)(2).
Please reference the subject application number when providing the requested information. All
revised and/or additional documentation shall be signed, sealed and dated (where needed), with an
electronic response submitted to my attention at: https://edocs.deq.nc.gov/Forms/NonDischarge-Branch-
Submittal-Form-Ver2.
If you have any questions regarding this request, please contact me at [phone] or
cord.anthony(kncdenr.gov. Thank you for your cooperation.
DocuSigned by:
Sincerely,
2D03237162FA4E5...
Cord Anthony, Engineer I
Division of Water Resources
cc: Raleigh Regional Office, Water Quality Regional Operations Section (Electronic Copy)
Kevin D. Davidson, PE — Agri -Waste Technology, Inc. (Electronic Copy)
Laserfiche File (Electronic Copy)
D E Q�� North Carolina Department of Environmental Quality I Division of Water Resources
512 North Salisbury Street 11617 Mail Service Center I Raleigh, North Carolina 27699-1617
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Mr. and Mrs. Lampuri
September 13, 2022
Page 2 of 5
A. Cover Letter:
1. No Comment
B. Application Fee:
1. No Comment
C. Application (SFRWWIS 06-16):
1. No Comment
D. Existing Permit:
1. No Comment
E. Property Ownership Documentation:
1. No Comment
F. Soil Evaluation:
1. Per [15A NCAC 02T .0604 (b)] a soil report that is representative of the site shall be submitted.
During the most recent site visit, Raleigh Regional Staff noted that:
"An extremely large amount of fill material will need to be added to the disposal area to provide the
minimum 12 inches of separation between the soil/application surface and the Seasonal High Water Table
(SHWT) depth. The addition of fill materials to a site to achieve the minimum 12 inches of separation
between the disposal surface and the SHWT is generally only suitable when there is naturally occurring
mineral soil present in the topsoil horizon and the slopes are less than 15%. All the topsoil in this area has
been removed. It is a very real possibility that the subsoil/fractured rock/parent material layer that is now the
surface of the proposed disposal area will cause lateral flow of applied effluent resulting in inadequate
wastewater treatment and run off from the disposal area.
The surface texture governing the instantaneous loading rate described in the application (Sandy
Loam in narrative; Silty Clay Loam in profile descriptions) was observed in a few locations (mostly in
ponded areas) in the proposed disposal field, but much of the area has a coarser surface texture (potentially
indicating significant erosion) with the presence of expansive clays just below the surface. These areas were
also very compacted. There were 2 areas in the field that had ponded water on them indicating a lack of
infiltration, the presence of expansive clays, and possibly a perched water table. As mentioned, adjacent areas
were very compacted and completely dry to at least several inches depth also indicating a lack of infiltration
and probable runoff. Multiple large rills were noted on the more sloped areas of the disposal field. The slopes
in these areas were estimated to be greater than 15%. In several places the rills have uncovered what appears
to be saprolite/parent material visible 2-3 inches below the surface.

Mr. and Mrs. Lampuri
September 13, 2022
Page 3 of 5
Many of the observations noted above signal a difficult time to be had stabilizing the proposed
fill and establishing vegetative cover. Additionally, a large amount of sediment is leaving the site and
entering an intermittent stream and pond on the property and adjacent properties. There is an ephemeral
stream that follows the northern property boundary that discharges into the intermittent stream
mentioned."
Regional Staff then listed the following questions in addition to the concerns above:
1. The differing textures of the native material (subsoil/saprolite/fractured rock/expansive clays) and fill
material will make lateral flow over the native material very likely. The application states that the fill
material should be incorporated into the native material to a depth of 5-6 inches. This may not be enough
mixing to integrate the fill and native materials. Additionally, fractured rock/saprolite/parent material was
observed just below the surface in many parts of the proposed disposal area that may significantly hinder
incorporation. How does the applicant plan to ensure that incorporation/integration of the fill material
with the subsoil/parent material native to the site will be done in a manner that prevents lateral flow
between the fill material and the native material?
2. There are currently multiple large rills in the proposed disposal area. This indicates a high erosion
potential. The typical prescribed texture for fill materials also has a high erosivity potential. Rills
indicating preferential flow in the disposal area raise the concern for cross connection between
incompletely treated wastewater and local surface waters and land not included in the proposed disposal
area. How does the applicant plan to address the high potential for erosion and migration of incompletely
treated wastewater from the disposal area?
3. Following on the previous question/observation; how does the applicant plan to ensure the establishment
and maintenance of competent vegetative cover on the easily eroded slopes of the proposed disposal area?
Please provide an updated soils evaluation to address the above concern that is signed and sealed by a North
Carolina Licensed Soil Scientist.
G. Engineering Plans:
1. Plan Sheet WW-2 contains a pole barn that has not been buffered out. Regional staff also noted the
existence of an ephemeral stream following the northern property boundary that discharges into an
intermittent stream. These surface water features shall be depicted and buffered. Additionally,
drainage structures have been included in the plan set. It is unclear whether water collection occurs
at individual points (the grates) and is then conveyed to the discharge point via solid walled pipes
or if the system utilizes a perforated pipe and lowers groundwater over the entire length (such as a
French drain). If the drains collect at a point, then the entrance shall be buffered as a surface
diversion. If the drains collect along the length, then they shall be buffered as a subsurface
groundwater lowering drainage system. Per [15A NCAC 02T .0604 (d)(3)] all required setbacks
shall be depicted.
2. The pole barn is described as containing an apartment and/or plumbing. Lines from the pole barn
are then shown to connect to the treatment and irrigation system. Application item IV.5. of the
Single -Family Residence Wastewater Irrigation System form (SFRWWIS 06-16) states that this is
a 5-bedroom single family residence. However, page WW-2 of the submitted engineering plans
states that this is a 4-bedroom house. This plan sheet also depicts two different inlets to the septic
tank, one from the proposed 4-bedroom house and one from a proposed garage/apartment.
According to 15A NCAC 02T .0601, the scope of the rules in that section are applicable for surface
irrigation of wastewater systems designed for one building single-family residences. Based on this
rule, single family systems permitted by our program shall not serve multiple residential buildings
served by the same treatment system. Please clarify the intended use of the proposed
garage/apartment.

Mr. and Mrs. Lampuri
September 13, 2022
Page 4 of 5
H. Specifications:
1. See comment F.I. Any management practices performed during installation to address the concerns
listed above shall be included in an updated specifications package.
I. Engineering Calculations:
1. Based on the loading rate and daily flow, my calculations showed that approximately 0.81 acres of
irrigation area are required. Additionally, the calculations included in the application package call
out a required area of 0.81195 acres. The proposed irrigation area, however, is only 0.80 acres. This
is insufficient for adequate irrigation. Per [15A NCAC 02T .0114 (b)] dwelling units shall be
designed to treat 120 gallons of sewage per day per bedroom.
2. Additionally, almost the entire area suitable for irrigation as described by the soil scientist is to be
utilized based on the design calculations. The engineering plans, however, only show drip irrigation
lines for approximately half of the suitable area. Plan sheets shall be updated to reflect drip line
coverage of the required irrigation area.
J. Site May:
1. No Comment
K. Operation and Maintenance Plan:
1. No Comment
L. Operation and Maintenance Agreement:
1. No Comment
M. County Health Department Denial Letter:
1. No Comment
N. Floodway Regulation Compliance:
1. No Comment
O. Threatened or Endangered Aquatic Species Documentation:
1. No Comment
P. Other Environmental Permits:
1. No Comment

Mr. and Mrs. Lampuri
September 13, 2022
Page 5 of 5
Q. Recommendations: (Response not required)
1. No Comment