HomeMy WebLinkAboutWQ0044258_Hydrogeologic Report Review_20230525DWR
Division of Water Resources
State of North Carolina
Department of Environmental Quality
Division of Water Resources
Non -Discharge Branch
Hydrogeological Investigation Report Review Form
WQ0044258
Micro Land Group, LLC
Micro Land Group WWIS
1015 Ashes Drive, Suite 102
Wilmington, NC 28405
Primary Permit Reviewer: Erick Saunders
Date submitted for Review: March 24, 2023
Hydrogeological Investigation Report Reviewer: Leah Parente
Date of review completion: May 25, 2023
1. Are the following elements included in the hydrogeological investigation report?
a. Report signed and sealed by a PE, LG, or LSS yes
b. Cursory examination of nearby properties and wells within 500 feet no
c. Field observations yes
d. Maps (topographic, overview, and site detail) yes
e. Published reports yes
f. Sufficient number of bore holes with drilling/sampling logs in the area
of system operation yes
g. Sufficient number of wells with drilling/sampling logs in the area of
system operation yes
h. Shallow aquifer tests with detailed supporting data and appropriate
analyses no*
Groundwater modeling results with supporting test data and reasonable
assumptions yes
List any missing elements, including others not mentioned above:
Supporting/field data for slug tests was not included.
WQ0044258
Micro Land Group WWIS
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2. Was a field visit conducted? No
b. Why was a field visit not conducted?
System not yet constructed, not deemed necessary at this point
Is a field visit recommended? Not at this time
3. Aquifer parameters were determined by slug tests
4. Was a mounding analysis submitted? Yes
5. Was the methodology used for analysis adequate? No
Please list areas of concern: Mounding Analysis did not include the month of
January or irrigation on all fields for the months of February, March, October,
November, or December.
6. Approximate depth to groundwater mound at steady state: Data not provided. In provided
analysis, depth to groundwater mound in the irrigation zones is greater than 1 foot
in all modeled scenarios.
7. Site conditions to be maintained as assumed in the analysis (e.g. drainage features):
Site is currently unconstructed, so site conditions will be changing.
8. Was a contaminate transport analysis submitted? No
Please provide commentary on the necessity of a contaminate transport analysis:
Due to the historic agricultural use of the subject site, a contaminant transport
analysis should be provided for the site. At minimum, the applicant should provide
sampling results for the following parameters: nitrogen, ammonia, sodium,
chloride, and phosphorus.
9. Effluent quality used in analysis demonstrating protection of 2L standards: not provided
10. Are there concerns with protection of 2L standards at the Compliance Boundary? N/A
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Micro Land Group WWIS
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11. Are monitoring wells needed at this facility? Yes
a. The number and locations of the monitoring wells should consider such factors as the
size of the application area, the locations of the Compliance and Review Boundaries,
and the existence of nearby water supply wells. Do the number and locations of the
monitoring wells proposed in the hydrogeological report concur with the
recommendations of the APS? Permanent monitoring wells were not proposed in the
hydrogeological report. The applicant should comment on the status of the
monitoring wells installed to collect data for this report. All monitoring wells
located inside the spray irrigation area must be permanently abandoned prior to
system operation. Location of monitoring wells to remain open should be provided.
b. The recommended substances to be monitored are as follows: To be determined
based on the results of the contaminant transport analysis.
12. The hydrogeologic report should meet the following standards described in the Aquifer
Protection Section's Hydrogeologic and Reporting Policy and Groundwater Modeling
Policy of May 31, 2007. Does the hydrogeologic report:
a. Focus on the waste application area?
Yes
b. Include borings advanced to a depth of 20 feet or more? Yes
c. Include enough borings in appropriate locations to create a reasonable
hydrogeologic conceptualization of the waste application area? Yes
d. Include a sufficient number of slug tests or pumping tests that were
properly performed and analyzed for basic hydrogeologic parameters? Yes
e. Utilize appropriate calculations or computer software to assess the
potential for mounding beneath the application area and/or
contaminant transport beyond the Compliance Boundary? Yes
f. Use recognized assessment methods that are consistent with standard
scientific practices and interpretations? Yes
g. Have analyses and/or conclusions which include "safety factors" such as
conservative assumptions to compensate for gaps in the field data or
questionable test results? Yes
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13. List in detail any additional information or items that are needed to evaluate the site:
• The Mounding Analysis did not include data for the month of January.
Additionally, irrigation on all fields was not modeled for the months of February,
March, October, November, or December. The applicant should resubmit the
Mounding Analysis with this missing information.
• Due to the historic agricultural use of the subject site, a contaminant transport
analysis should be provided for the site. At minimum, the applicant should provide
sampling results for the following parameters: nitrogen, ammonia, sodium, chloride,
and phosphorus.
Permanent monitoring wells were not proposed in the hydrogeological report. The
applicant should comment on the status of the current monitoring wells that were
installed to collect data for the hydrogeologic report. All monitoring wells located
inside the spray irrigation area must be permanently abandoned prior to system
operation. Location of monitoring wells to remain open, if any, should be provided
by the applicant.
• On page 16 of the hydrogeologic report, the extinction depth for evapotranspiration
was modeled using data based on deep-rooted deciduous trees. The applicant should
clarify why data for deciduous trees was used in the model when the site is
predominantly used for row cropping.
• On page 18 of the hydrogeologic report, it is unclear if the hydraulic conductivity
values for the surficial aquifer used for the model calibration of the Mounding
Analysis were the published USGS values listed in Table 6. The applicant should
clarify if those literature values or calculated values from the site investigation were
used for the model calibration.
14. List in detail any special conditions related to groundwater monitoring or hydrogeological
issues that should be included in the permit: none
15. Other areas of concern or importance: mounding is a potential limiting factor in the water
balance
16. Recommendation on permit issuance based on hydrogeological investigation report:
Request additional information based on above comments.