HomeMy WebLinkAboutNC0001422_3-Final CSA Guideline Adjs DWR Position Edits_20150805CSA GUIDELINE ADJUSTMENTS DWR Review June 2015
Tracked Changes Version, May 14, 2015
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NCDENR Division of Water Resources Position:
Clarification of certain items in the Comprehensive Site Assessment (CSA) Guidelines submitted
on August 13, 2014 is provided by the Division of Water Resources (Division) in order to
facilitate completion of the groundwater assessments at the Duke Energy Coal Ash
Impoundments. The Division does not intend to change the CSA Guidelines, which were provided
to Duke Energy to ensure compliance with NCAC 2L standards and technical direction presented
in the Coal Act Management Act Senate Bill 729 (CAMA). If a change to the CSA Guidelines
proposed by Duke Energy leads to more clarity, the Division will consider the merit of the
proposed changes on a site-by-site basis while reviewing the CSA report document. If the
Division determines the data and related reporting are inadequate, then additional information
may be requested to complete the site assessments.
This document provides guidelines for those involved in the investigation of contaminated soil
and/or groundwater, where the source of contamination is from:
Incidents caused by activities subject to permitting under G.S. 143 -215.1 .
Incidents caused by activities subject to permitting under G.S. 87 -88.
Incidents arising from agricultural operations, including application of agricultural
c hemicals, but not including unlawful discharges, spills or disposal of such
chemicals .
COMPREHENSIVE SITE ASSESSMENT (CSA)
NOTE: Regional Offices may request additional information in support of the CSA to aid in their review
and will not approve the CSA if any of the elements specified below have not been included or have not
been sufficiently addressed.
Minimum Elements of the Comprehensive Site Assessment Report:
A. Title Page
Site name, location and Groundwater Incident number (if assigned) and Permit
Number;
Date of report;
Responsible Party and/or permittee, including address and phone number;
Current property owner including address and phone number;
Consultant/contractor information including address and phone number;
Latitude and longitude of the facility; and
Seal and signature of certifying P.E. or P.G., as appropriate.
Note to NCDENR Reviewers:
Proposed CSA Guideline Adjustments are indicated as follows:
Proposed deletions are shown as crimson -colored strike -through text .
Proposed additions are shown as blue-colored text .
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B. Executive Summary
The Executive Summary should provide a brief overview of the pertinent site information (i.e.,
provide sufficient information to acquaint the reader with the who, what, when, where, why and
how for site activities to date).
1. Source Information:
Type of contaminants
2. Initial abatement/emergency response information.
3. Receptor Information:
Water supply wells;
Public water supplies (wells, surface water intakes);
Surfac e water bodies;
Wellhead protection areas;
Deep aquifers in the Coastal Plain physiographic region;
Subsurface structures; and
Land use.
4. Sampling/Investigation Results:
Nature and extent of contamination;
Maximum contaminant concentrations;
Site Hydrogeology.
5. Conclusions and Recommendations.
C. Table of Contents
First page number for each section listed.
List of figures (all referenced by number and placed in a single section following
contents text).
List of tables (all referenced by number and placed in a single section following
contents text).
List of appendices.
D. Site History and Source Characterization
Provide a history of property ownership and use. Indicate dates of ownership, uses
of the site, and potential sources of contaminants.
Discuss the source(s) of contamination, including primary and secondary sources.
For permitted activities, describe nature of activity, permitted waste, application of
all instances of over -application/irrigation of wastes or water
Summarize assessment activities and corrective actions performed to date including
emergency response, initial abatement, primary and secondary source removal.
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Discuss geographical setting and present/future surrounding land uses.
E. Receptor Information
Provide a site map showing labeled well locations within a minimum of 1500 feet of
the known extent of contamination. Key to the table and maps described.
NOTE: As the known extent of contamination changes, the receptor survey must be updated to
reflect the change. This applies throughout the Receptor Information section.
In table format, list all water supply wells, public or private, including irrigation
wells and unused wells, (omit those that have been properly abandoned in
accordance with 15A NCAC 2C .0100) within a minimum of 1500 feet of the known
extent of contamination. Note whether well users are also served by a municipal
water supply.
For each well, in clude well number, well owner and user names, addresses and
telephone numbers, use of the well, well depth, well casing depth, well screen
interval, and distance from source of contamination;
NOTE: It will often be necessary to conduct any or all of the following in order to ensure reliability
in a water supply well survey:
Call the city/county water department to inquire about city water connections;
Visit door -to-door (make sure that you introduce yourself and state your
purpose to residents prior to exam ining their property) to obtain accurate
description of water usage, and if some residents are not at home, ask
surrounding neighbors who are home about the water usage at those residences.
Even if a public water line is available, some residents still use their well water
and are not connected to the public water system; and ,
Search for water meters and well houses.
Site map showing location of subsurface structures (e.g., sewers, utility lines,
conduits, basements, septic tanks, drain fields, etc.) within a minimum of 1,500 feet
of the known extent of contamination;
Table of surrounding property owner addresses;
Discuss the availability of public water supplies within a minimum of 1,500 feet of
the source area, including the distance and location to the ne arest public water lines
and the source(s) of the public water supply;
Identify all surface water bodies (e.g., ditch, pond, stream, lake, river) within a
minimum of 1,500 feet of the source of contamination;
Determine the location of any designated wellhe ad protection areas as defined in 42
USC 300h -7(e) within a minimum of 1,500 feet of the source of contamination.
Identify and discuss the location of the water supply well(s) for which the area was
designated a wellhead protection area, and the extent of the protected area. Include
Note to NCDENR Reviewers:
With respect, the language as-is versus as-proposed of Section E did not lend itself well to “internal”
editing. Respectfully again, please receive/review as presented, with the languages at least in close
proximity, to hopefully help facilitate your review. L. Armstrong
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information about the well owner, well -construction specifications (especially at
screened intervals), pumping rate and pumping schedule. Information regarding
designated wellhead protection areas may be obtained by contacting t he Public
Water Supply Section at (919) 707 -9083;
Discuss the uses and activities (involving possible human exposure to
contamination) that could occur at the site and adjacent properties. Examples of
such activities and uses include but are not limited to use of a property for an office,
manufacturing operation, residence, store, school, gardening or farming activities,
recreational activities, or undeveloped land;
Determine whether the contaminated area is located in an area where there is
recharge to an unconfined or semi -confined deeper aquifer that is being used or may
be used as a source of drinking water. Based on a review of scientific literature on
the regional hydrogeology and well construction records and lithological logs for
deeper wells in the area, identify and describe the deep aquifers underlying the
source of contamination. Include information on the depth of the deep aquifer in
relation to the surficial saturated zone, the lithology and hydraulic conductivity of
the strata between the surfi cial aquifer and the deeper aquifer, and the difference in
groundwater head between the surficial aquifer and the deeper aquifer. Discuss the
local and regional usage of the deep aquifer and the draw down from major pumping
influences. Also, specify the di stance from the source of contamination to major
discharge areas such as streams and rivers. Cite all sources and references used for
this discussion.
NOTE: This requirement (last bullet) only pertains to contamination sources in the Coastal Plain
physiographic region as designated on a map entitled "Geology of North Carolina" published by
the Department in 1985. However, recharge/discharge, hydraulic conductivity, lithology, head
difference, etc. is also important information at mountains and piedmont sites.
Consistent with the DWR’s August 13, 2014 Notice of Regulatory Requirement:
The CSA Report will include information obtained from the Drinking Water Well
and Receptor Survey Report submitted September 2014, the Supplement to
Drinking Water Supp ly Well and Receptor Survey Report submitted November
2014, and updated information obtained between these noted reports and
submittal of the CSA Report. The receptor survey is required by 15A NCAC 02L
.0106(g) and shall include identification of all rece ptors within a radius of 2,640
feet (one -half mile) from the established compliance boundary identified in the
respective National Pollutant Discharge Elimination System (NPDES) permits.
Receptors shall include, but shall not be limited to, public and priv ate water
supply wells (including irrigation wells and unused or abandoned wells) and
surface water features within one -half mile of the facility compliance boundary.
The results of the receptor survey shall be presented on a sufficiently scaled
map. The m ap shall show the coal ash facility location, the facility property
boundary, the waste and compliance boundaries, and all monitoring wells listed
in the respective NPDES permits. Any identified water supply wells shall be
located on the map and shall have the well owner's name and location address
listed on a separate table that can be matched to its location on the map.
Consistent with Senate Bill 729:
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The CSA Report will identify all drinking water supply wells within one -half mile
down -gradient from the established compliance boundary of the impoundment
and submit the Survey to the Department. Information including well locations,
the nature of water uses, available well construction details, and information
regarding ownership of the wells will be prov ided for the above noted wells.
The CSA Report will include the Duke Energy Laboratory analytical results from
the drinking water supply wells required to be sampled by the Department.
NCDENR Division of Water Resources Position :
The Division does not intend to change the CSA Guidelines . Specific information is
expected in order to evaluate site conditions at and in the vicinity of the coal ash ponds
that are germane to significant exposure pathways and potential receptors. Several of
sub-elements proposed for delet ion in Section E are related to identification and
characterization of potential environmental receptors (human and ecological) and
determination of the limits of the study area or system boundaries , which a re key
elements of a conceptual model as stated in standard industry practice reference ASTM
E1689 Guide for Developing Conceptual Site Models for Contaminated Sites . The Division
will evaluate the content of Section E Receptor Information along with comp onents of the
refined conceptual site models presented in the CSA reports with respect to receptor and
exposure pathway information to determine if the data are adequate to meet CAM A
requirements for groundwater assessment and corrective action . If the Division considers
the data provided in the CSA reports are inadequate, additional data may be requested.
Data p resentation does not have to follow a prescriptive format; however,
documentation of relevant water supply well receptor information is expected by the
Division to support evaluat ion of potential risk to receptors and conceptual site models .
Data requirements related to Section E Receptor Information that should be considered
include :
T he Division acknowledges the difficulty with determining the k nown extent of
contamination at this time since potential plume assessments are not complete .
With this in mind, the Div i sion expects all drinking water wells located 2,640-feet
downgradient from the established compliance boundary be documented in the
CSA reports as specified in the CAMA requirements. T he Division may request
additional data after review of well receptor and water quality data in a CSA
report.
In general, s ubsurface utilities are expected to be mapped within 1500 -ft of the
known extent of contamination in order to evaluate the potential for preferential
pathways . An explanation must be provided in the CSA report if the subsurface
utility mapping requirements are modified. Details concerning si te conditions such
the possibility of a shallow, perched, or fluctuating water table resulting from site
operations intercepting subsurface utilities must be documented. I f the utility
mapping requirements are modified , Duke Energy must be able to document tha t
the subsurface utilities are not potential preferential pathways for contaminant
migration in the CSA reports.
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A determination of whether the contaminated area is located in an area where
there is recharge to an unconfined or semi -confined deeper aquife r that is being
used or may be used as a source of drinking water is expected by the Division. The
groundwater assessment findings may indicate a continuous confining unit cannot
be delineated beneath across the Coastal Plain sites; therefore, potential im pacts
to deeper aquifers should be evaluated.
The Division maintains that all surface water bodies (e.g., ditch, pond, stream, lake,
river) within a minimum of 1,500 feet of the source of contamination be identified
as these features relate to identificati on of potential receptors and exposure
points, both key elements of a conceptual site model.
F. Regional Geology and Hydrogeology
Provide a brief description of the regional geology and hydrogeology. Cite all
references.
G. Site Geology and Hydrogeology
Describe the soil and geology encountered at the site. Use the information obtained
during assessment activities (e.g., lithological descriptions made during drilling,
probe surveys, etc.). This information should correspond to the geologic cross
sections required in N. below; and
Based on the results of the groundwater investigation , describe the site
hydrogeology, including a discussion of groundwater flow direction, hydraulic
gradient, hydraulic conductivity and groundwater velocity. Discuss the effects of the
geologic and hydrogeological characteristics on the migration, retardation, and
attenuation of contaminants.
H. Soil Sampling Results
Using figures and tables to the extent possible, describe all soil sampling performed
to date and provide the rational e for sample locations, number of samples collected,
etc. Include the following information:
Location of soil samples;
Date of sampling;
Type of soil samples (from excavation, borehole, Geoprobe, etc.);
Soil sample collection procedures (split spoon, grab, hand auger, etc.)
Depth of soil samples below land surface;
Soil sample identification
Soil sample analyses;
Soil sample analytical results (list any contaminant detected above the method
detection limit); and ,
Identify any sample analytical results that exceed the applicable cleanup levels.
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Identify any soil sample analytical results that exceed the EPA Region 9 Regional
Screening Levels.
NOTE: Information related to H. above should correspond to the sampling location and sampling
results maps required in N. below.
NCDENR Division of Water Resources Position:
The Division does not agree with the proposal to identify soil analytical results that exceed
EPA Region 9 soil screening levels. Instead, the Division is in the process of finalizing clean
closure guidelines for cleanup that will meet protection of groundwater criteria for 2L
standards, which will include soil screening levels. Details related to the partial draft
guidelines are provided below:
Clean Closure Guidelines
The Division’s goal is that facilities remediate all discharges or releases of constituents to
unrestricted use levels.
• For groundwater, the unrestricted use level is the North Carolina Division of Water
Quality, 2L groundwater standard (2L) or site-specific background concentration.
• For soil, the unrestricted use level is either the site-specific background concentration
or the lowest of a soil screening level (SSL) protective of groundwater.
Determining Soil Screening Levels for Clean Closure Soil Remediation Goals
The methodology the Division recommends for calculating unrestricted use levels or soil
screening levels (SSLs) for contaminant migration to groundwater was developed in the
Preliminary Soil Remediation Goals (PSRG) document (identified below)to identify chemical
concentrations in soil with the potential to migrate and contaminate groundwater.
• SSLs protective of groundwater are calculated with a soil leachate model using default
values from 15A NCAC 2L groundwater standard or the 2L groundwater interim maximum
allowable concentration as target groundwater concentrations and take into consideration
fate and transport parameters.
• The Preliminary Soil Remediation Goals (PSRG) table contains a column with soil
remediation goals titled (Protection of Groundwater PSRG) that should be used in
evaluating soil-to-groundwater values that meet and are protective of the 15A NCAC 2L
groundwater quality standards. A link to the IHSB PSRG table can be found here:
http://portal.ncdenr.org/c/document_library/get_file?uuid=0f601ffa-574d-4479-bbb4-
253af0665bf5&groupId=38361. Please note that the Division of Waste Management
updates this table during the first and third quarter of each calendar year.
• A transport model is included in the PSRG table for calculating other soil values not
specifically listed in the table in order to meet Protection of Groundwater Criteria. Rule 15A
NCAC 2L .0202 (c) does specify substances that are not permitted in groundwater and
indicates that even those which are not specifically listed in the rule are not allowed above
the practical quantitation limit (PQL), unless they are naturally occurring. The approved
laboratory method PQL for the substance can be used in the equation if there is no
specifically listed 15A NCAC 2L standard.
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• Background concentrations of naturally occurring metals in soil at a site can be
established using EPA guidance for comparing background and chemical concentrations in
soil for CERCLA sites: http://www.epa.gov/oswer/riskassessment/pdf/background.pdf
I. Groundwater Sampling Results
Using figures and tables to the extent possible describe the groundwater sampling performed to
date and provide the rationale for sample locations (based on source and contaminant type),
number of samples collected, etc. Include the following information:
Locati on of groundwater samples and monitoring wells;
Date of sampling;
Groundwater sample collection procedures (bailer, pump, etc.);
Groundwater sample identification and whether samples were collected during
initial abatement, CSA, etc.;
Groundwater sample an alyses;
Groundwater sample analytical results (list any contaminant detected above the
method detection limit; and ,
Identify all sample analytical results that exceed 15A NCAC 2L or interim standards.
NOTE: Information related to I. above should correspond to the sampling location and sampling
results maps required in N. below.
J. Hydrogeological Investigation
Describe the hydrogeological investigation performed including all methods, procedures and
calculations used to characterize site hydrogeological conditions. The following information should
be discussed and should correspond to the maps and figures required below:
Groundwater flow direction;
Hydraulic gradient (horizontal and vertical);
Hydraulic conducti vity;
Groundwater velocity;
Contaminant velocity;
Slug test results *;
Aquifer test results *;
Plume's physical and chemical characterization; and
Fracture trace study if groundwater in bedrock is impacted *.
NOTE: Check with the Regional Office prior to performing these tests and study to see if necessary
for the site.
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NOTE: Contaminant velocity will be addressed in the Groundwater Model Report portion of the
Corrective Action Plans.
NCDENR Division of Water Resources Position:
The Division agrees with the proposed change in content. Discussion of contaminant velocity is
appropriate for inclusion in the Groundwater Modeling Report portion of the Corrective Action
Plans rather than the CSAs. This is consistent with direction provided in the NCDENR
Groundwater Assessment Plan (GAP) Conditional Letters of Approval.
K. Groundwater Modeling Results
Groundwater modeling or predictive calculations may be necessary at some sites (source area
proximate to surface water, source area located within wellhead protection area or source area
overlying semi-confined or unconfined deeper Coastal Plain aquifer) to verify, based on site specific
hydrogeological conditions, whether groundwater contamination poses a risk to receptors. For
contamination shown to pose a risk to receptors, groundwater modeling may be necessary to
determine an appropriate cleanup level for contaminated groundwater. Modeling should illustrate
the input data used to complete the model and will generally be required for natural attenuation
proposals (see Groundwater Modeling Policy at
http://portal.ncdenr.org/web/wo/apskiwpro/oolicv).
NOTE: Input data for models should be derived from site specific information with limited assumptions
or estimates. All assumptions and estimated values including biodegradation rates must be conservative
(predict reasonable worst-case scenarios) and must be well documented.
NOTE: Groundwater Modeling Results will be included in the Corrective Action Plans per NCDENR
DWR Conditional Approval of Revised Groundwater Assessment Work Plan letters.
NCDENR Division of Water Resources Position:
The Division agrees with the proposed change in content. Direction has been given by the Division to
include groundwater modeling results in the Corrective Action Plans per NCDENR Conditional Approval
of Revised GAP letters. Some discussion related to how site assessment data and the resulting refined site
conceptual model will be incorporated into the groundwater models is appropriate and should be
presented in the CSAs.
L. Discussion
Nature and extent of contamination, including primary and secondary source areas,
and impacted groundwater and surface water resources;
Maximum contaminant concentrations; and,
Contaminant migration and potentially affected receptors .
M. Conclusions and Recommendations
If corrective action will be necessary, provide a preliminary evaluation of remediation alternatives
appropriate for the site. Discuss the remediation alternatives likely to be selected. Note that for
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impacts to groundwater associated with permitted activities, corrective action pursuant to 15A
NCAC 2L .0106(k), (I) and (m) is not applicable, unless provided for pursuant to 15A NCAC 2L
.0106(c) and (e) or through a variance from the Environmental Management Commission (EMC).
N. Figures
71/2 minute USGS topographic quadrangle map showing an area within a minimum
of a 1,500 -foot radius of the source of contamination and depicting the site location,
all water supply wells, public water supplies, surface water intakes, surface water
bodies, designated well head protection areas, and areas of recharge to deeper
aquifers in the Coastal Plain that are or may be used as a sourc e for drinking water;
The CSA Report Figures will include a 7½ minute USGS topographic quadrangle map
showing an area within a minimum of 2,640 feet (one-half mile) from the established
compliance boundary identified in the respective National Pollutant Discharge Elimination
System (NPDES) permits. This map will include depiction of the following, as applicable:
the fossil station property boundary;
ash basin compliance boundaries;
2,640 feet (one -half mile) offset of the ash basin compliance boundaries;
w ater supply wells identified in the Drinking Water Well and Receptor Survey
Report submitted September 2014, the Supplement to Drinking Water Supply
Well and Receptor Survey Report submitted November 2014, and updated
information obtained between these not ed reports and submittal of the CSA
Report;
public water supplies;
surface water intakes;
surface water bodies;
designated well head protection areas; and,
areas of recharge to deeper aquifers in the Coastal Plain that are or may be used
as a source for dr inking water.
Site map locating source areas, site boundaries, buildings, all water supply wells
within a minimum of 1,500 feet, named roads/easements/right -of-ways, subsurface
utilities, product or chemical storage areas, basements and adjacent properties,
scale and north arrow;
At least two geologic cross sections through the saturated and unsaturated zones
intersecting at or near right angles through the contaminated area using a
reasonable vertical exaggeration. Indicate monitoring well/sample boring/sample
locations and analytical results for soil samples. Identify the depth to the water
table. Provide a site plan showing the locations of the cross sections;
Note to NCDENR Reviewers:
With respect, the language as-is versus as-proposed of Section N did not lend itself well to “internal”
editing. However, we have attempted to place language relative to certain figures (i.e., the USGS Map and
the Site Maps) at least in close proximity, to hopefully help facilitate your review. Respectfully again, we
request your receipt/review as presented.
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Site map(s) showing the results of all soil sampling conducted. Indicate sampling
identifications, sampling depths, locations and analytical results;
Site map(s) showing the results of all groundwater sampling conducted. Indicate
sampling locations, monitoring well identifications, sample identifications, and
analytical results;
Separate gr oundwater contaminant iso -concentration contour maps showing total
volatile organic compound concentrations, total semi -volatile organic compound
concentrations and concentrations for the most extensive contaminant. Maps should
depict the horizontal and ve rtical extent. Contour line for applicable 2L standard
should be shown in bold;
Site map(s) showing the elevation of groundwater in the monitoring wells and the
direction of groundwater flow. Contour the groundwater elevations. Identify and
locate the datu m (arbitrary 100', USGS, NGVD) or benchmark. Indicate the dates that
water level measurements were made. There should be one map for each series of
water level measurements obtained;
Groundwater contaminant iso -concentration contour cross -section; and ,
Site map(s) showing the monitoring wells.
NOTE: If possible, use a single base map to prepare site maps using a map scale of 1 inch = 40 feet
(or a smaller scale for large sites, if necessary). Maps and figures should include conventional
symbols, notations, labeling, legends, scales, and north arrows and should conform to generally
accepted practices of map presentation such as those enumerated in the US Geological Survey
pamphlet, "Topographic Maps".
The CSA Report Figures (plan views), as applicable, will b e based on like or similar
base maps developed from 2014 aerial photography, with associated
photogrammetric topography. Considered collectively , the CSA Report Figures will
include the following information :
ash basins and associated compliance boundari es;
fossil station property boundaries within the limits of the particular map,
buildings within the limits of the particular map;
named roads within the limits of the particular map;
subsurface utilities having a significant impact on groundwater flow and /or
transport from the ash basin;
product or chemical storage areas associated with ash basin operations; and,
scale and north arrow.
NOTE: The CSA Report will include adjacent property information obtained from the
Drinking Water Well and Receptor Survey Report submitted September 2014, the Supplement
to Drinking Water Supply Well and Receptor Survey Report submitted November 2014, and
updated information obtained between these noted reports and submittal of the CSA Report.
soil sample locations and analytical results (subjectively as supportive of
conveying findings while affording depiction clarity);
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groundwater sample locations and analyt ical results (subjectively as supportive
of conveying findings while affording depiction clarity);
separate groundwater contaminant iso -concentration contour maps for
constituents exceeding 2L standards with c ontour line for applicable 2L standard
shown bo ld (or otherwise demarcated);
separate groundwater elevation contour maps for each holistic series of water
level measurements obtained with:
elevation of groundwater in the monitoring wells;
direction of groundwater flow indicated;
identification of the e levation datum; and,
date(s) that the water level measurements were made.
the monitoring wells.
The CSA Report Figures will include at least two geologic cross sections through the
saturated and unsaturated zones intersecting at or near right angles through the ash
basin(s) as proposed in the approved Proposed Groundwater Assessment Work Plan .
The c ross -sections will comprise:
a reasonable vertical exaggeration;
boring, monitoring well, soil sample, and/or groundwater sample locations and
analytical results (sample locations and analytical results subjectively as
supportive of conveying findings whil e affording depiction clarity);
groundwater contaminant iso -concentration contours for constituents exceeding
2L standards;
depiction of the water table; and,
a site map showing the locations of the cross sections.
NCDENR Division of Water Resources Positi on:
The Division does not intend to change the CSA Guidelines. Proposed changes in data
presentation in Section N will be considered during the Division’s rev iew of the CSA
reports. If the Division’s review of a CSA report indicates data presentation relat ed to the
figures provided in Section N is inadequate, then additional data and/or data
presentation may be requested. Technical direction related to data presentation in
Section N that should be considered includes :
The d irection for data presentation in site assessment deliverables outlined in
Comment 23 from the November 2014 Review of Groundwater Assessment Work
Plan letters sent to Duke Energy.
Strike out the caveats that read “(subjectively as supportive of conveying findings
while affording depiction clarity)” from proposed text revisions . Direction
provided in Sections H. Soil Sampling Results and I. Groundwater Sampling
Results , respectively, gives specific instruction related to presentation of both soil
and groundwater analytical results detected above PQLs along with those results
above numeric regulatory limits. This approach is suggested in order to allow the
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Division Regional offices to have sufficient information in a format that promotes
an effective review of the CSA documents. I n a ddition, the Division Regional
Offices m ay request additional information in support of the CSA to aid in their
review .
Map groundwater analytical results related to detection monitoring constituents
and inorganic parameters as identif ied in the USEPA April 2015 Final R uling 40
CFR Parts 257 and 261 , including boron, calcium, chloride, conductivity, pH,
sulfate, and total dissolved solids .
Map groundwater analytical results related to assessment monitoring constituents
as identified in the USEPA April 2 015 Final Ruling 40 CFR Parts 257 and 261 ,
including aluminum, antimony, arsenic, barium, beryllium, cadmium, chromium,
copper, iron, lead, manganese, mercury, molybdenum, selenium, sulfate, sulfide,
and thallium . In addition, map the distribution of vanad ium as an assessment
monitoring constituent .
O. Tables
List all water supply wells , public or private, including irrigation wells and unused
wells, (omit those that have been properly abandoned in accordance with 15A NCAC
2C .0100) within a minimum of 1500 feet of the known extent of contamination For
each well, include the well number (may use the tax map number), well owner and
user names, addresses and telephone numbers, use of the well, well depth, well
casing depth, well screen interval and distanc e from the source of contamination;
List the names and addresses of property owners and occupants within or
contiguous to the area containing contamination and all property owners and
occupants within or contiguous to the area where the contamination is ex pected to
migrate; 2,640 feet (one -half mile) from th e established ash basin compliance
boundaries. For each well, include that information obtained during and since the
formerly noted Receptor Surveys.
List the results for groundwater samples collected i ncluding sample location; date of
sampling; sample collection procedures (briefly/concisely as “bailer”, “pump”, etc.);
sample identifications; sample analyses; and sample analytical results (list
demarcate (bold or otherwise) any contaminant detected above the method
detection limit in bold ); and ,
List for each monitoring well, the monitoring well identification number, date water levels
were obtained, elevations of the water levels, the land surface, top of the well casing,
scree ned interval and bottom of the well.
CSA GUIDELINE ADJUSTMENTS DWR Review June 2015
Tracked Changes Version, May 14, 2015
Reviewers & Users: See Document End Note
Page 14 of 15
NCDENR Division of Water Resources Position:
The Division does not intend to change the CSA Guidelines. Proposed changes in tables in Section
O will be considered during the Division’s review of the CSA reports. If the Division’s review of a
CSA report indicates tables provided in Section O is inadequate, then revised tables may be
requested. Documentation of specific water supply well receptor information is expected to be
presented in a certain format to facilitate review and as indicated below:
Direction outlined in Comments 22 and 23, respectively, from the November 2014
Review of Groundwater Assessment Work Plan letters sent to Duke Energy for data
presentation in site assessment deliverables will be followed.
Highlight groundwater analytical results that exceed numeric regulatory values in some
manner that distinguishes those results from those below the limits. Note the numeric
regulatory value for a constituent in the table.
P. Appendices
Boring logs and lithological descriptions;
Well construction records;
Standard procedures used at site for sampling, field equipment decontamination,
field screening, etc.;
Laboratory reports and chain -of-custody documents;
Copies of any permits or certificates obtained, permit number, permitting agency,
and
Modeling data and results;
Slug/pumping test data; and
Certification form for CSA .
The CSA Reports will be sealed and signed by a groundwater -experienced
Professional Engineer or Professional Geologist registered in North Carolina.
NOTE: Modeling data and results will be included in the Corrective Action Plans per NCDENR
DWR Conditional Approval of Revised Groundwater Assessment Work Plan letters.
NCDENR Division of Water Resources Position:
The Division accepts the proposed change in Section P to not include groundwater modeling
results and related data in the CSA Reports; instead, providing information related to
groundwater modeling in the Corrective Action Plans . The Division does require relevant
information provided in the Certification Form for the CSA Reports and does not accept the
proposed change for the CSA Guidelines.
CSA GUIDELINE ADJUSTMENTS DWR Review June 2015
Tracked Changes Version, May 14, 2015
Reviewers & Users: See Document End Note
Page 15 of 15
Document End Note:
This Microsoft Word file was generated from a PDF version of the August 12, 2014 Guidelines for
Comprehensive Site Assessment attached to NCDENR’s August 14, 2015 Notice of Regulatory Requirements
letter. Generation comprised saving the PDF file as a Microsoft Word file using PDF Converter Assistant
within PDF Converter Enterprise 8.2, with post-conversion manual formatting. Any
discrepancy/disparity between the original PDF file and this Word file are unintentional.