NCD991278953_19990608_National Starch & Chemical Corp._FRBCERCLA RD_Remedy Evaluation Plan for OU-1-OCR

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' ' ' REPORT
Remedy Evaluation Plan
·for Operable Unit One
National Starch & Chemical Company
Cedar Springs Road Plant Site
Salisbury, North Carolina
· June 1999
BBL
BLASLAND, BOUCK & LEE, INC. ---------------engineers & scientists
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BBL
TECHNICAL REPORT
Remedy Evaluation Plan
for Operable Unit One
RECEIVED
JUN 14 1999
SUPERFUNo' SECTION
National Starch & Chemical Company
Cedar Springs Road Plant Site
Salisbury, North Carolina
June 1999
BLASlAND,BOUCK&LEE.INC, _________________ _
engineers & scientists
8 South River Road
Cranbury, New Jersey 08512-9502
[phone]
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Table of Contents
Section 1.
Section 2.
Section 3.
19290562.WPD ·· 6(8/j9
Introduction .......................................... 1-1
1.1 Remedy Evaluation Plan Objectives ..... _ 1-1
1.2 OU1 Activity Summary . . . 1-2 1.3 Preliminary Analyses of OU 1 Remedy
Effectiveness ...... 1-3
1.3.1 Conceptual Hydrogeologic Model . . . . . . . . . . . . .. 1-3 1.3.2 Numerical Ground-Water Flow Modeling .............. 1-4
1.3.3 Comprehensive Statistical Analysis .................. 1-4
1.4 Remedy Evaluation Plan Structure ................... 1-4
Hydrogeologic Evaluation .............................. 2-1
2.1 Plume Periphery Well Conceptual Model .............. 2-1 2.1.1 Bedrock Pumping for Remediation in a Piedmont
Setting ........................................ 2-1
2.2 Plume Periphery Well Pumping ..................... 2-2
Ground-Water Quality and Geochemical Evaluation ......... 3-1
3.1
3.1.1
3.1.1.1
3.1.1.2
3.1.2
3.1.2.1
3.1.2.2
3.1.3
3.1.3.1
3.1.3.2
3.1.4
3.1.4.1
3.1.4.2
3.1.5
3.1.5.1
3.1.5.2
3.2
3.2.1
3.2.2
3.2.3
3.2.4
3.2.5
3.2.6
3.3
3.3.1
3.3.2
3.3.3
Preliminary Identification of Plume Periphery
Constituents ................................... 3-1
Acetone ....................................... 3-1
Frequency and Occurrence of Impacts ................ 3-1
Constituent Fate ................................ 3-1
1,2-Dichloroethane (1,2-DCA) ...................... 3-2
Frequency and Occurrence of Impacts ................ 3-2
Constituent Fate . . . . . ......................... 3-2
Bis(2-Chloroethyl)ether (SCEE) ..................... 3-2
Frequency and Occurrence of Impacts ................ 3-2
Constituent Fate ................................ 3-3
1,2-Dichloropropane (DCP) ........................ 3-3
Frequency and Occurrence of Impacts ................ 3-3
Constituent Fate .......... _ ..................... 3-4
Methylene Chloride (MC) .... _ ............ _ ........ 3-4
Frequency and Occurrence of Impacts ................ 3-4
Constituent Fate ................................ 3-4
Proposed Ground-Water Sampling ................... 3-5
Proposed Locations .............................. 3-5
Proposed Sampling Methods ....................... 3-5
Volatile Organic Constituents ....................... 3-6
Semivolatile Organic Constituents ................... 3-6
Inorganic Constituents ............................ 3-6
Natural Attenuation Indicator Parameters .............. 3-7
Proposed Surface Water Sampling .................. 3-8
Proposed Locations .............................. 3-8
Proposed Sampling Methods ............. _ .... _ . 3-8
Volatile Organic Constituents ...................... 3-9
BLASLAND, BOUCK & LEE. INC.
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Section 4.
Section 5.
Table.
Figures.
29290562.\.VPO .. 6/8n9
3.3.4
3.3.5
Semivolatile Organic Constituents .......... .
Other Parameters ...................... .
... 3-9
.... 3-9
Schedule ............................................ 4-1
4.1
4.2
4.3
4.4
4.5
Plume Periphery Well Pumping ..................... 4-1
Ground-Water Elevation Measurements ............... 4-1
Ground-Water and Surface Water Sampling ........... 4-1
Data Evaluation ................................. 4-1 Remedy Evaluation Report ......................... 4-1
References ........................................... 5-1
1
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Wells Included in Plume Periphery Extraction System Remedy
Evaluation Monitoring Program
Site Location Map
Site Map
Plume Periphery Extraction Well Conceptual Model
Schedule
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1. Introduction
On behalf of National Starch & Chemical Company (NSCC), Blasland, Bouck & Lee, Inc. (BBL) has prepared this Remedy Evaluation Plan for Operable Unit One (OUI) of the Cedar Springs Road Plant Site (Site) located in Salisbury, North Carolina. Figure I presents a Site Location Map. Figure 2 presents a Site Map.
The Site is situated on a 500-acre parcel and includes operating laboratory and manufacturing facilities. The Site also includes two separate tributaries of Grants Creek, the Unnamed Tributary and the Northeast Tributary. There is a topographic ridge which provides the divide between the drainage basins of each tributary.
The Site has four operable units, including:
• OU I which addresses ground-water impacts attributed to historic use of wastewater effluent trenches (Trench Area) on the western portion of the Site within the drainage basin of the Unnamed Tributary. The selected remedy for OUI includes a two-phased ground-water pump and treat system. The first phase consists of the extraction of ground water from the Plume Periphery Extraction System (PPES) wells located adjacent to the Unnamed Tributary. The second phase consists of the extraction of ground water from the Trench Area Extraction System (T AES) wells located in the vicinity of the former Trench Area.
• ou2· which addresses soil impacts in the vicinity of the former waste-water trenches. The selected remedy includes no further action owing to the operation of the ground-water collection systems.
• OU3 which addresses ground-water impacts attributed to former unlined wastewater treatment lagoons, underground terra-cotta sewerage, and miscellaneous spills within the drainage basin of the Northeast Tributary. The selected remedy includes extraction of ground water to maintain substantial hydraulic control over a zone of potential dense non-aqueous phase liquid (DNAPL).
• OU4 which addresses soil impacts in the vicinity ofOU3. The selected remedy for OU4 includes evaluation of Natural Degradation to address residual soil impacts.
1.1 Remedy Evaluation Plan Objectives
The results of Preliminary Analyses, which are discussed in Section 1.3, performed on the OUI remedy have indicated that the operation of the TAES continues to be successful in minimizing the migration of constituents in ground water from the Trench Area to the Plume Periphery. The Preliminary Analyses have also indicated that the operation of the PPES has not been as successful and may continue to be less successful.
Additional analyses are required to fully evaluate the OU I remedy. These analyses are required to address specific data gaps in the existing data set. These data gaps include:
• complete hydraulic data under non-pumping conditions;
• current ground-water quality data from monitoring wells located between the Trench Area and the Plume Periphery Area; and
• geochemical analyses from the OU I area.
The objective of this Remedy Evaluation Plan is to set forth a program to address the data gaps listed above in order to complete the analyses and make informed recommendations as to future remedial activities in OU!.
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1.2 OU1 Activity Summary
The timeline of OU! activities is summarized as follows:
• a site investigation of the Trench Area was performed in 1976 and 1977;
• ground-water monitoring was performed quarterly from 1979 to 1985;
• the Site was proposed for inclusion on the National Priorities List in 1985;
• a Remedial Investigation was performed from_ 1986 to 1988;
• a Remedial Investigation Report was prepared and submitted to the United States Environmental Protection Agency (USEPA) in 1988 (IT Corp., June 1988);
• a Feasibility Study was prepared and submitted to the USEPA in 1988 (IT Corp., September 1988);
• pursuant to a Record of Decision (ROD) dated June 30, 1988, a Remedial Design Investigation was perfonned from 1988 to 1990;
• a Final Design Report was prepared and submitted to the USEPA in 1990 (IT Corp., June 1990);
• PPES wells were installed and hydrofractured in 1990;
• operation of the PPES (EX-01, EX-02, EX-03 and EX-04) was initiated in 1992;
• TAES wells (EX-05, EX-06, EX-07, EX-08, EX-09 and EX-I 0) were installed in 1993;
• quarterly monitoring of ground-water in OU I was initiated in 1993;
• the TAES Ground-Water Pre-Treatment facility was constructed in 1995;
• extraction and treatment of Trench Area ground-water commenced in 1996;
• the USEPA issued a Five Year Review for OU! in 1996 (USEPA, June 1996) deferring comment on the efficacy of the selected remedy due to insufficient data;
• the pumps in the Plume Periphery Wells were lowered within the borehole to increase well yield in 1996;
• in conjunction with the OUJ remedial design, a Conceptual Hydrogeologic Model for the Site was prepared and submitted to the USEPA in 1998 (BBL, March 1998) which includes a discussion of the OU! remedial action;
in conjunction with the OU3 remedial design, a Ground-Water Flow Model for the Site was prepared and submitted to the USEPA in 1998 (BBL, June 1998) which includes a discussion of the OU! remedial action;
• in conjunction with the OU2 Five Year Review, a Comprehensive Data Review was prepared and submitted to the USEPA in I 998 (BBL, August 1998) which includes a discussion of the OU I remedial action; and
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• a reduction in sampling frequency (quarterly to annual) for OU! ground-water monitoring was granted in March 1999.
1.3 Preliminary Analyses of OU1 Remedy Effectiveness
A preliminary evaluation of the effectiveness of the OU! remedy was performed in 1998. The preliminary evaluation of the remedy consisted of the following:
• preparation of a Conceptual Hydrogeologic Model;
• performance of numerical ground-water flow modeling; and
• comprehensive statistical analysis of the ground-water quality data collected from monitoring and extraction wells.
1.3.1 Conceptual Hydrogeologic Model
The Conceptual Hydrogeologic Model developed for the Site is presented in the Technical Memorandum on the Site Conceptual Model (BBL, March 1998). The Conceptual Model evaluated the site-specific data as it compares to the understood geology and hydrogeology of the Piedmont Province. The following geologic understanding of the Site has been derived based on various investigations:
• the Site is underlain by metamorphosed intrusive mafic rock or mafic lava flows;
• the bedrock has been weathered in-place forming a saprolite and a transition zone of saprolite, partially weathered rock and competent rock fragments;
• the rock underlying the Site has been observed to have both a steeply dipping foliation and steeply dipping fractures;
• fractures follow the traces of topographic lineaments in the vicinity of the Site (i.e., the northwest trending ridge, the Northeast Tributary and the lower reaches of the Unnamed Tributary); and
• a narrow shear zone trending northeast has been inferred to intersect the northeast trending lineaments roughly coincident with the topographic draw in the vicinity of the Site wastewater treatment lagoons.
The conceptual hydrogeologic model of ground-water flow within the Piedmont Province is applicable to the Site. The conceptual model for the Site includes the following:
• ground-water flow occurs within ground-water compartments roughly coincident with the watershed boundaries of perennial streams;
• ground water is introduced to the compartments through recharge from precipitation;
• ground water flows both horizontally and vertically within the ground-water compartment, ultimately discharging to surface water in the stream;
• due to differences in primary porosity, the saprolite and transition zones act as storage reservoirs and fractures within the underlying bedrock act as conduits for ground-water flow from the overlying regolith; and
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• a well screened in bedrock will intersect fractures to convey ground water from the overlying regolith.
The conceptual model docs not support the use of deep bedrock wells in remedial efforts in the Piedmont. Ground-
water extraction from the Transition Zone is preferred. The Plume Periphery Wells are each approximately 200 feet
in depth with an open borehole from the Transition Zone to the bottom of the borehole. The Trench Area Extraction
Wells are less deep, ranging from 85 feet to 135 feet below ground surface (bgs). and are screened in the Transition
Zone and Saprolite. Therefore, the operation of the Plume Periphery Wells is not supportable by the Conceptual
Model and the operation of the Trench Area Extraction Wells is supportable by the Conceptual Model.
An extension of the Conceptual Model to address the specific operation of the Plume Periphery Wells is included
in Section 2.
1.3.2 Numerical Ground-Water Flow Modeling
The results of the numerical ground-water flow modeling are summarized in the Technical Memorandum for Site
Ground-Water Flow Modeling (BBL, June 1998) and presented in more detail in the Final Design Report for OU3
(BBL, December 1998). The numerical ground-water flow modeling included construction, calibration and
sensitivity analyses of a three-dimensional numerical model. The numerical ground-water flow modeling supported
the conceptual model in that the results of the model, using Site-specific and appropriate model input parameters,
were consistent with those predicted from the conceptual model.
In the vicinity of the PPES, the numerical modeling was less accurate with respect to the simulation of the heads
under pumping conditions. This is due to the small-scale, highly heterogeneous flow regime. However, under non-
pumping conditions, the calculated heads were consistent with pre-pumping observations. In the vicinity of the
TAES, the model was more consistent. The modeling also indicated that the TAES Wells were effective in providing
hydraulic control over the Trench Area.
1.3.3 Comprehensive Statistical Analysis
The results of the comprehensive statistical analysis were attached to the Five Year Review for OU2 (BBL, August
1998). The comprehensive statistical analysis included performance of statistical tests to evaluate the data collected
in the 21 quarterly sampling events from 1993 to 1998. The objectives of the data evaluation were to:
• identify general characteristics, statistical outliers, and concentration trends;
• identify constituents of concern (COCs) that could be eliminated from further monitoring based on
concentrations less than the Performance Standards; and
• recommend changes to improve the current monitoring program.
The results of the statistical analyses indicated that the operation of the TAES has been generally successful and that
the operation of the PPES has been less successful. The data trends from monitoring and extraction wells associated
with the TAES generally have been either decreasing or stable whereas the data trends from the monitoring and
extraction wells associated with the PPES generally have been either stable or increasing.
1.4 Remedy Evaluation Plan Structure
The remainder of this Remedy Evaluation Plan is separated into the following sections:
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• Section 2 presents a plan for further Hydrogeologic Evaluation;
• Section 3 presents a plan for further Ground-Water Quality and Geochemical Evaluation;
• Section 4 presents a proposed schedule for implementation of the plan presented herein; and
• Section 5 presents a list of materials referenced in this plan.
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2. Hydrogeologic Evaluation
This section presents additional information related to the understood hydrogeology of the Site and a plan for
additional data collection. The goal of this section is to provide the justification for performance of a hydrogeologic
evaluation in which the PPES well pumping will be ceased to allow for re-equilibration of the aquifer to natural
gradients.
2.1 Plume Periphery Well Conceptual Model
Following are two hydrogeologic situations which can explain the apparent inability to demonstrate complete
effectiveness of the PPES. These situations include:
• the use of bedrock pumping to achieve hydraulic capture of ground water is not supported by the conceptual
hydrogeologic model of ground-water flow in the Piedmont; and
• the operation of the PPES (at a location far from the source area) before initiation of the TAES pumping may
have spread impacts further than they might have spread under natural gradients.
2.1.1 Bedrock Pumping for Remediation in a Piedmont Setting
As discussed in various reports prepared by BBL, the operation of bedrock well pumping at the Site has not been
demonstrated to be successful in achieving the remedial objectives of containment or aquifer restoration. The
underlying reasons for this apparent inability can be explained using the conceptual model for ground-water flow in
the Piedmont, particularly as it relates to the site-specific data.
As summarized in Section I, and more fully described in the Technical Memorandum on the Site Conceptual Model
(BBL, March 1998), the ground-water flow in the bedrock is primarily through steeply dipping fractures. Due to
greater effective porosity, the overlying Transition Zone and Saprolite act as a reservoir from which water either flows
in to or out of the fractures in the bedrock, depending on the hydraulic gradient. Therefore, ground-water flow
between the zones occurs where the steeply dipping fractures intersect the Transition Zone.
A bedrock extraction well will draw water from the formation where the fractures intersect the borehole. The
extraction well can only influence flow in fractures which have a hydraulic connection to the borehole. The ground-
water flows vertically into a fracture and horizontally within the fracture to the borehole. Pumping creates a reduction
in the hydraulic head within fractures and other permeable regions of the bedrock. The fractures and permeable
portions of bedrock can be de-watered.
Once the fractures and penneable portions of the bedrock de-water, flow of ground water vertically from the overlying
Transition Zone can be significantly restricted. It is a well-documented phenomena that unsaturated hydraulic
conductivity is significantly less than saturated hydraulic conductivity (Freeze and Cherry, 1979). This is particularly
true for fractured media, as the number of potential alternative flow paths are fewer than in a porous media and
wetting/drying cycles can cause precipitation of 111 incrals within the fractures. Due to the decrease in the vertical
hydraulic conductivity, the water in the Transition Zone may flow more readily horizontally and past the area of the
bedrock pumping.
While the boreholes also screen the Transition Zone, the maximum drawdown in the well will be the saturated
thickness of the Transition Zone in the vicinity of the well. Therefore, the head differential can be smaller than if
there was a hydraulic connection between the Transition Zone and the bedrock. If the drawdown is smaller, the radius
of influence may also be small. Figure 3 presents a graphical depiction of this concept.
Under this scenario, there arc two pathways by which ground water may bypass the bedrock extraction well:
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• horizontally within the Transition Zone (which is understood to be the primary pathway for ground-water flow
in any case); and/or
• within fractures which may not be hydraulically connected to the bedrock extraction well.
The impacts which arc observed in monitoring wells located on the southwestern side of the Unnamed Tributary do
not necessarily indicate that the stream does not act as a discharge feature. Underthe scenarios described above, these
observed impacts may be related to:
• ground water may flow beyond the extraction wells horizontally in the transition zone and discharge vertically
to the underlying bedrock because the hydraulic head is lower in the bedrock than in the stream; and/or.
• the route by which ground water flows in the fractures is tortuous and the route of connection crosses the
Unnamed Tributary.
In either case, ground-water flows upward from the bedrock to the Transition Zone and Saprolite in the vicinity of
the Unnamed Tributary. The natural ground-water elevation is generally higher than the stream elevation, thus
ground-water flows into the stream. While the stream does act as a discharge feature, some ground water may
underflow the stream for some short distance. Because upward hydraulic gradients exist on both sides of the stream,
the ground-water will eventually discharge to the stream.
2.2 Plume Periphery Well Pumping
The original design for the PPES contemplated a combined pumping rate from the four extraction wells of
approximately 86 gallons per minute (gpm). In the second quarter of 1998, the extraction rates were decreased to
approximately 3 I gpm to evaluate the effect on the system of reduced extraction rates. The reduction of extraction
rates did not appreciably alter the ground-water quality observed in the Plume Periphery. Concentrations of
constituents remained stable in the Third and Fourth Quarters of 1998.
This plan includes a proposal to cease the pumping from the PPES in its entirety and evaluate the response by
monitoring the impacts on ground-water elevation within the extraction wells and monitoring wells. This will aid
in understanding the non-pumping gradients and flow paths. To provide additional information on the response of
the aquifer to the cessation of pumping, short-term and long-term ground-water elevation monitoring will be
performed.
The short-term monitoring will consist of the use of pressure transducers and data loggers to register the immediate
response of the aquifer. For a period of 24 hours prior to the cessation of the pumping and 72 hours thereafter,
pressure transducers will provide ground-water elevation measurements on a periodic basis. The pressure transducers
will be installed in the following wells:
• monitoring wells NS-22, NS-26, NS-27, NS-29, NS-30, NS-31 and NS-28 (background); and
• extraction wells EX-0 I, EX-02, EX-03 and EX-04.
In addition to the short-tenn monitoring, synoptic manual ground-water elevation measurements will be obtained from
Site monitoring wells and stream gauges. Subsequent to the performance of the short-term monitoring, ground-water
elevations and stream elevations will be monitored on a monthly basis to evaluate the longer-term response.
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3. Ground-Water Quality and Geochemical Evaluation
Subsequent to the cessation of the PPES pumping, a period of three months will be allowed for re-equilibration of
the aquifer prior to the collection of ground-water quality and geochemical data. The objectives of the ground-water
quality and geochemical evaluation will be to:
• collect data on the ground-water quality from monitoring wells located between the PPES and the T AES, which
have not been sampled since the RI, to understand any changes in plume dynamics;
• collect geochemical data which has never been collected at the Site; and
• collect data to evaluate alternative ground-water remedies, including Monitored Natural Attenuation.
3.1 Preliminary Identification of Plume Periphery Constituents
The following presents a description of the five organic constituents identified in the Plume Periphery Area in terms
of their occurrence in OU I and their understood environmental fate. Although this Remedy Evaluation Plan focuses
on these constituents, all ROD-specified constituents will be evaluated in the proposed sampling and evaluation
activities.
3.1.1 Acetone
I 3.1.1.1 Frequency and Occurrence of Impacts
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Detections of acetone in the OU I wells are summarized as follows:
Number of Percentage of
Number of Samples> Samples>
Monitoring Percentage of Performance Performance
Well ID Events Number of Detections Detections ITotal) Standard* Standard
Qualifiers Non-"B" ··w· Total
EX-01 21 8 3 11 52 0 (0 ll) 0
EX-02 20 15 5 20 100 14 (5 ll) 70
EX-03 21 16 5 21 100 7 (5 B) 33
EX-04 21 14 5 19 90 0 (0 ll) 0
NS-29 21 11 4 15 71 8 ( 4 ll) 38
NS-30 21 6 4 10 48 0 (0 B) 0
NS-31 21 12 5 17 81 8 (4 B) 38
NS-32 21 0 4 4 19 O (OB) 0
* Performance Standard= 3,500 ug/L: "13" qualified detections greater than the Pcrfonnancc Standard arc indicated in parentheses but were
not included in the calculation of the percentage of detections greater than the Perform an ct: Standard.
As shown in the above table, acetone was detected in all eight of the OU I wells although several of the detections
were "B" qualified, indicating laboratory contamination of the samples. The detections greater than the Performance
Standard appear Io be clustered around wells EX-02, EX-03, NS-29, and NS-31; all of the detected concentrations
in the remaining four wells are less than the Performance Standard.
3.1.1.2 Constituent Fate
Acetone is readily biodegradable in ground water by means ofa variety of aerobic and anaerobic metabolic processes,
including aerobic respiration, anaerobic respiration, and fermentation. Acetone can be used by many types of
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naturally occurring microorganisms as a primary growth substrate and biodegradation results in byproducts such as
carbon dioxide, methane, and/or water. Optimal environmental conditions conducive to natural biodegradation of
acetone in ground water include the presence of either oxidizing or reducing conditions; circumneutral pH ( e.g .. 6
<pH< 8); adequate temperature (e.g.,> 10 degrees C); and an adequate supply of nutrients.
3.1.2 1,2-Dichloroethane (1,2-DCA)
3.1.2.1 Frequency and Occurrence of Impacts
Detected concentrations of 1,2-DCA in OU I wells are summarized as follows:
Number of Percentage of
Number of Samples> Samples>
Monitoring Percentage of Performance Performance
Well ID Events Number of Detections Detections (Total) Standard* Standard
Oualifiers Non-"B" "B" Total
EX-01 21 7 0 7 33 I 5
EX-02 20 14 0 14 70 14 70
EX-03 21 15 0 15 71 15 71
EX-04 21 12 0 12 57 2 10
NS-29 21 18 0 18 86 15 71
NS-30 21 5 0 5 24 3 14
NS-31 21 13 0 13 62 10 48
NS-32 21 0 0 0 0 0 0
* Performance Standard = 5 ug/L.
1,2-DCA was detected in seven of the eight OUI wells and the lowest number of detections were in wells EX-01,
NS-30, and NS-32. These three wells and EX-04 showed the fewest number of detections greater than the
Perfomiance Standard; the greatest number of detections greater than the Performance Standard appeared in wells
EX-02, EX-03, and NS-29.
3.1.2.2 Constituent Fate
1,2-DCA is potentially biodegradable in ground water by means of both aerobic and anaerobic metabolic processes.
1,2-DCA can be biodegraded by means of aerobic respiration, anaerobic respiration, fermentation, cometabolic
processes, and a variety of reductive dechlorination processes. End products of 1,2-DCA biodegradation may include
carbon dioxide, methane, ethane, water, and chloride ions. In the absence of other electron donors (substrates) 1,2-
DCA biodegradation is expected to be slow to moderate. Therefore, optimal environmental conditions conducive to
natural biodcgradation of 1,2-DCA in ground water include the presence ofother organic carbon sources (e.g., TOC
> IO mg/Lor anthropogenic carbon sources such as acetone); the presence of either oxidizing or reducing conditions;
circumncutral pH ( e.g., 6 < pH < 8); adequate temperature (e.g.,> IO degrees C): and an adequate supply of nutrients.
3.1.3 Bis(2-Chloroethyl)ether (BCEE)
3.1.3.1 Frequency and Occurrence of Impacts
Detected concentrations of BCEE in OU I wells are summarized as follows:
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Number of Percentage of
Number of Samples> Samples>
t\-lonitoring Percentage of Performance Performance
Well ID E\'ents Number of Detections Detections (Total) Standard* Standard
Ouafiilers ,Von-"B" "B" Torai
EX-01 21 13 0 13 62 11 53
EX-02 20 20 0 20 100 20 100
EX-03 21 20 0 20 95 20 95
EX-04 21 20 0 20 95 20 95
NS-29 21 21 0 21 100 21 100
NS-30 21 20 0 20 95 20 95
NS-31 21 20 0 20 95 20 95
NS-32 21 3 0 3 14 3 14
• Performance Standard = 5 ug/L.
BCEE was detected in all of the sampling events for one of the eight wells and in all but one of the sampling events
for five of the eight wells, with infrequent occurrences in wells EX-0 I and NS-3i All of the detected concentrations
were greater than the Performance Standard with the exception of well EX-01.
3.1.3.2 Constituent Fate
13CEE is potentially biodegradable in ground water by means of both aerobic and anaerobic metabolic processes.
l3CEE can potentially be biodegraded by means of aerobic respiration, anaerobic respiration, and fermentation. It
is expected that the end products of BCEE biodegradation would be carbon dioxide, methane, water, and chloride
ions. BCEE can potentially be metabolized as a primary substrate (food source) during aerobic respiration.
Environmental conditions conducive to natural biodegradation of BCEE in ground water include the presence of
either oxidizing or reducing conditions; circumneutral pH ( e.g., 6 < pH < 8); adequate temperature ( e.g., temp> I 0
degrees C); and an adequate supply of nutrients.
3.1.4 1,2-Dichloropropane (DCP)
I 3.1.4.1 Frequency and Occurrence of Impacts
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Detected concentrations of DCP in OU I wells are summarized as follows:
Number of
Monitoring Percentage of
Well ID Events Number of Detections Detections ITotal)
Qualifiers Non-"8" .. Ii'" Total
EX-Ill 21 6 0 6 29
EX-02 20 17 0 17 85
EX-03 21 18 0 18 86
EX-04 21 9 0 9 43
NS-29 21 15 0 15 71
NS-30 21 3 I) 3 14
NS-31 21 11 I) 11 52
NS-32 21 I 0 I 0
• Performance Standard = 6 ug/L.
BLASLAND. BOUCK & LEE. INC.
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Number of Percentage of
Samples> Samples>
Performance Performance
Standard* Standard
2 10
17 85
18 86
4 19
14 66
3 14
10 47
0 0
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DCP was detected infrequently in wells EX-01, EX-04, NS-30, and NS-32; and wells EX-01. EX-04, and NS-32
showed the fewest number of detected concentrations greater than the Performance Standard, indicating a clustering
of detections in wells EX-02, EX-03, NS-29, NS-30, and NS-31.
3.1.4.2 Constituent Fate
DCP is potentially biodegradable in ground water by means of aerobic and anaerobic metabolic processes. DCP can
potentially be biodegraded by means of aerobic respiration, anaerobic respiration, fermentation, and cometabolic
processes. It is expected that the end products ofDCP biodegradation may include carbon dioxide, methane, propane,
water, and chloride ions. Optimal environmental conditions conducive to natural biodegradation ofDCP in ground
water include the presence of other organic carbon sources (e.g., TOC > IO mg/Lor anthropogenic carbon sources
such as acetone); the presence of either oxidizing or reducing conditions; circumneutral pH (e.g., 6 <pH< 8);
adequate temperature (e.g.,> IO degrees C); and an adequate supply of nutrients.
3.1.5 Methylene Chloride (MC)
3.1.5.1 Frequency and Occurrence of Impacts
Detected concentrations of MC in OU I wells are summarized as follows:
Number of Percentage of
Number of Samples> Samples>
l\.fonitoring Percentage of Performance Performance
Well ID Events" Number of Detections Detections (Total Standard* Standard
Qualifiers Non-"B" "B"" Total
EX-01 19 2 6 8 42 I ( I 13) 13
EX-02 18 5 5 10 56 4 (5 13) 40
EX-03 19 4 7 II 58 3 (6 B) 27
EX-04 19 3 7 10 53 O (3 B) 0
NS-29 19 4 7 11 58 2 (4 B) 18
NS-30 19 1 5 6 32 0 (3 Il) 0
NS-31 19 4 9 13 68 4 (7 ll) 31
NS-32 19 4 6 10 53 0 (3 13) 0 -. -* Performance Standard=) ug/L: "B" qualillcd dctcct10ns greater than the Performance Standard are md1catcd m parentheses but
wt:rc not included in th1.: calculation of the percentage of detections greater than the Performance Standard.
" Analytical results for 4093 and I Q94 were not reported which decreases the total number of monitoring events for methylene
chloride by two compared to other constituents.
As shown in the above table, 50 to 83 percent of the total number of detections of MC were "B" qualified, indicating
laboratory contamination. MC was detected as non-"13" qualified concentrations least frequently in wells EX-0 I, EX-
04, and NS-30, and these wells, along with NS-32, showed the fewest number of detections greater than the
Performance Standard.
3.1.5.2 Constituent Fate
MC (also known as dichloromethane) is potentially biodegradable in ground water by means of both aerobic and
anaerobic metabolic processes. MC can probably be biodcgraded by means of aerobic respiration, anaerobic
respiration. fermentation, cometabolic processes, and a variety of reductive dechlorination processes. It is expected
that the end products of MC biodcgradation may include carbon dioxide, methane, water, and chloride ions. Optimal
environmental conditions conducive to natural biodegradation of MC in ground water include the presence of other
organic carbon sources (e.g .. TOC > 10 mg/Lor anthropogenic carbon sources such as acetone); the presence of
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either oxidizing or reducing conditions; circumneutral pH ( e.g., 6 <pH< 8); adequate temperature (e.g.,> IO degrees
C); and an adequate supply of nutrients.
3.2 Proposed Ground-Water Sampling
3.2.1 Proposed Locations
Table I lists wells from which ground-water samples will be collected to characterize current ground-water conditions
in the area between the Trench Area and the Plume Periphery Area and to monitor the effects of discontinuing the
plume periphery extraction well pumping. A number of wells located in the area between the TAES and PPES have
not been sampled since the Remedial Design Investigation in 1989. Sampling of these wells has not been performed
since the PPES has been in operation. These wells will be sampled to provide data on the current ground-water
quality and changes that may have occurred since the last sampling event. Other wells are proposed to be sampled
as part of the on-going monitoring programs associated with OUs I and 2. ·
Volatile organic compounds (VOCs), semivolatile compounds (SVOCs), and inorganic compounds that are listed
in the ROD will be sampled at all of the wells listed. Natural attenuation indicator parameters will be analyzed for
in samples from select wells.
3.2.2 Proposed Sampling Methods
Ground-water level measurements will be collected at each monitoring well prior to sampling. Ground-water level
measurements will be made relative to an established reference point on the well casing. The depth to water (DTW)
will be measured by introducing an electronic water level indicator probe into the well and slowly lowering the probe
down the well column. The apparent DTW will be recorded to the nearest 0.0 I foot at the depth indicated by the
pulsating tone of the probe.
Ground-water samples will be collected using low-flow purging and sampling methods except at wells where this
protocol is unable to be implemented (e.g., extraction wells that contain in-place plumbing and pumps and monitoring
well NS-32 which exhibits artesian conditions). Low-flow sampling will be conducted in accordance with protocols
presented in the United States Environmental Protection Agency (USEPA) documents Ground Water Sampling
Procedure, Low Stress /Low Flow) Purging and Sampling, Final Ground Water Sampling SOP, March 16, 1998 and
Environmental Investigations Standard Operating Procedures and Oualitv Assurance Manual, May 1996.
A bladder pump equipped with a Teflon™ bladder, assembled with TeflonT" and stainless-steel fittings will be used
for purging and sampling. Dedicated Teflon™-lined polyethylene tubing will be employed to discharge ground water
from the bladder pump. The bladder pump intake (bottom of pump) will be lowered to the middle of the screened
interval for all wells. The initial pumping rate in each well will be set from 200 to 500 milliliters per minute
(111 I/min). The duration of bladder discharge will not be included in determination of pumping rates. If necessary,
the pumping rate will be adjusted so that the decrease in water level in the well is less than 0.3 foot. During purging,
the following parameters will be measured and recorded approximately every five minutes using a YSI 6920 water
quality meter equipped with an in-line flow-through cell: pH, temperature, specific conductance, dissolved oxygen
(DO). turbidity, and oxidation-reduction potential (ORP). To avoid air entrapment within the discharge tubing, the
llow cell will be positioned above the top of casing. Sampling will be conducted when these parameters stabilize
within the following ranges for three consecutive readings over a 15-minute time period at five-minute intervals.
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C\ ... ·'·:·:paf3meter . ·::,:,:,/• Stabilii8ti0ci:Criterioit •
pH ~1-0.1 oH unit
Conductivity +/-3 percent
Oxidation-Reduction Potential +/-IO millivolts
Dissolved Oxvoen +/-IO percent
Turbidity +/-IO oercent
I fturbidity is the only parameter not within the stabilization criterion, a sample will be collected based on stabilization
of the other criteria. Samples will be collected at a flow rate between I 00 ml/min and 250 ml/min. All sample bottles
will be provided by the laboratory and will be filled by letting the ground water flow down the inner wall of the bottle
to minimize turbulence.
After the samples are collected, they will be placed on ice in coolers and picked up by a courier from the analytical
laboratory or shipped by overnight courier to the analytical laboratory. Samples will be stored and transported under
. full chain-of-custody procedures.
3.2.3 Volatile Organic Constituents
Ground-water samples will be analyzed for the following Target Compound List (TCL) VOCs as listed in the ROD:
• Acetone;
• Benzene;
• Chloroform;
• 1,2-Dichloroethane;
• 1,2-Dichloroethylene;
• 1,2-Dichloropropane;
• Ethylbenzene;
• Methylene chloride;
• 4-Nitrophenol;
• Toluene;
I, 1,2-Trichlorethane;
• Trichloroethylene;
• Vinyl Chloride; and
• Xylenes (total).
VOCs will be analyzed using EPA method 624.
3.2.4 Semivolatile Organic Constituents
Ground-water samples will be analyzed for Bis(2-chloroethyl)ether and Bromodichloromethane. These SVOCs will
be analyzed for using EPA method 625.
3.2.5 Inorganic Constituents
Ground-water samples will be analyzed for the following ROD-listed Target Analyte List (TAL) inorganic
constituents:
• Arsenic;
• Barium;
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• Beryllium; I
• Cadmium;
• Chromium (YI);
• Manganese;
• Nickel;
• Selenium; and
• Zinc.
Inorganic constituents will be analyzed for using EPA method 200.7.
3.2.6 Natural Attenuation Indicator Parameters
A number of documents have been provided by the US EPA to direct the use and evaluation of natural attenuation
(NA) at sites impacted with chlorinated solvents (USEPA, 1997, USEPA, 1999, USEPA, 1998). These documents
recommend the sampling and analysis of various ground water parameters as indicators of NA occurrence. The
presence and relative amounts of certain NA parameters enable the identification of the mechanism by which NA is
occurring. Ground-water samples will be analyzed for the following NA indicator parameters:
• Total organic carbon (TOC)-TOC indicates the quantity of biologically available organic carbon used for
cell growth;
• Chemical oxygen demand (COD) -COD indicates the potential magnitude of oxygen consumption by . . inorganic processes;
• Total dissolved solids (TDS) -TDS indicates the quantity of dissolved inorganic matter;
• Alkalinity -Alkalinity buffers potential pH changes associated with biodegradation processes (which may
produce organic acids as intermediate byproducts). Alkalinity can also serve as an alternate electron acceptor;
• Chloride -Chloride ions are a byproduct of dechlorination reactions;
• Phosphorus -Phosphorus is a macronutrient required for cell growth;
• Ammonia -Ammonia can be a byproduct of Denitrification and Animonification, which are common oxidation-
reduction reactions known to consume organic matter in groundwater. Ammonia can also serve as a substrate
during Nitrification, which is a common oxidation-reduction reaction that can degrade certain chlorinated
compounds cometabolically;
• Nitrate -Nitrate is an alternate electron acceptor;
• Nitrite -Nitrite is an alternate electron acceptor;
• Total Kjeldahl nitrogen (TKN) -TKN indicates the quantity of organic nitrogen (e.g., urea) and ammonia
nitrogen in ground water samples. Nitrogen is a macronutrient required for cell growth;
• Nitrogen -Nitrogen is a macronutrient required for cell growth;
• Sulfate -Sulfate is an alternate electron acceptor through sulfate reduction;
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• Sulfide -·sulfide is the product of sulfate reduction;
• Iron (II) (ferrous iron) -Ferrous iron is a metabolic byproduct of iron reduction, which 1s a common
oxidation-reduction reaction known to consume organic matter in ground water;
• Methane -Methane is a metabolic byproduct of Methanogenesis, which is a common oxidation-reduction
reaction known to consume organic matter in ground water. Methane can also serve as a substrate during
methane oxidation, which is a common oxidation-reduction reaction that can degrade certain chlorinated
compounds cometabolically;
• Ethane -Ethane can be a byproduct of certain dechlorination reactions;
• Ethcnc -Ethene can be a byproduct of certain dechlorination reactions;
• Phospholipid fatty acids (PLFA)-PLFAs are intact components of all viable cell walls. Their enumeration
in ground water samples provides a quantitative means to evaluate the in-situ biomass, community structure, and
metabolic status of indigenous ground-water microorganisms known to degrade organic compounds;
• Carbon dioxide -Carbon dioxide is a metabolic byproduct of several common oxidation-reduction reactions
known to consume organic compounds in ground water, including aerobic respiration, denitrification, iron
reduction, manganese reduction, sulfate reduction, and methanogenesis. Carbon dioxide can also serve as an
electron acceptor during methanogenesis; and
• Dissolved Hydrogen -Hydrogen is a metabolic byproduct of reductive dechlorination. Concentrations of
dissolved hydrogen can also be used to evaluate redox processes, and thus the efficiency of reductive
dechlorination in ground water.
NA parameters will be sampled at the following six wells: NS-31, NS-29, NS-21, NS-22, NS-26, NS-6, and NS-25
(Background).
3.3 Proposed Surface Water Sampling
3.3.1 Proposed Locations
Surface water elevations and flow measurements will be collected at two locations, SG-1 and SG-2, in the Unnamed
Tributary.
Surface water samples will be collected at two locations in the Unnamed Tributary, SW-06 and SW-07.
3.3.2 Proposed Sampling Methods
Flow measurements will be collected concurrent with the surface water sampling. Surface water flow will be
measured using the velocity-area method in accordance with US EPA ( I 996). The velocity-area method calculates
flow (cubic feet/second) as the average velocity (feet/second) multiplied by the cross-sectional area (square feet) of
the channel. The velocity of the channel will be measured with a current meter, and the area of the channel will be
measured or calculated using an approximation technique (USEPA, 1996).
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Surface water samples will be collected sequentially from the most downstream location to the most upstream
location. Samples will be collected by slowly lowering a dedicated Teflon bailer into the water column to middepth
while angling the bailer so that the tip of the bailer is facing upstream. Care will be taken not to disturb sediment.
In accordance with EISOPQAM, water will be carefully poured from the bailer into the 40-mL VOC vials,
minimizing sample aeration. VOC samples will be checked for air space by turning the bottle over after capping and
tapping to check for air bubbles. If any bubbles are present, another clean 40-mL vial will be filled and checked.
Samples will be immediately placed in iced coolers, and all surface water samples will be documented on a chain-of-
custody prior to transport to the analytical laboratory for analysis.
3.3.3 Volatile Organic Constituents
Surface-water samples will be analyzed for the following ROD-listed TCL VOCs:
• Acetone;
• Benzene;
• Chloroform;
• 1,2-Dichloroethane;
• 1,2-Dichloroethylene;
• 1,2-Dichloropropane;
• Ethylbenzene;
• Methylene chloride;
• 4-Nitrophenol;
• Toluene;
• 1,1,2-Trichlorethane;
• Trichloroethylene;
• Vinyl Chloride; and
• Xylenes (total).
VOCs will be analyzed for using EPA method 624. The use of this analytical method will assure the achievement
of detection limits that are equal to or less than the ROD-mandated Performance Standards for undiluted samples.
3.3.4 Semivolatile Organic Constituents
Surface-water samples will be analyzed for Bis(2-chloroethyl)ether and Bromodichloromethane. These SVOCs will
be analyzed for using EPA method 625. The use of this analytical method will assure the achievement of detection
limits that are equal to or less than the ROD-mandated Performance Standards for undiluted samples.
3.3.5 Other Parameters
Surface-water samples will be analyzed for the following ROD-listed TAL inorganic constituents:
• Arsenic;
• Barium;
• Beryllium;
• Cadmium;
Chromium (VI);
• Manganese;
• Nickel;
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• Selenium; and
• Zinc.
Inorganic constituents will be analyzed using EPA method 200.7.
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4. Schedule
Figure 4 presents the schedule for the implementation of the Remedy Evaluation Plan. The following sections
describe the individual tasks and the time frame for their completion.
4.1 Plume Periphery Well Pumping
Pumping of the plume periphery extraction wells will cease within one month of approval of this plan. Adequate time
will be required to procure and set-up the equipment necessary to register the immediate response of the aquifer.
4.2 Ground-Water Elevation Measurements
Ground-water elevation measurements will consist of both short-term and long-term monitoring. Pressure transducers
will be installed in select monitoring wells and the ground-water elevation will be measured in these wells for the 24-
hours prior to cessation of the plume periphery extraction. A comprehensive round of depth to water measurements
will be collected in the Site monitoring wells and stream gauges prior to plume periphery pumping cessation. After
the plume periphery extraction is discontinued, the pressure transducers in the select monitoring wells will continue
to record ground-water elevation measurements on a periodic basis for 72-hours. To gauge the long-term response
of the aquifer, monthly depth to water measurements will be collected from Site monitoring wells and stream gauges
for a minimum period of six months.
4.3 Ground-Water and Surface Water Sampling
Ground-water and surface water samples will be collected approximately three months following the cessation of
pumping from the plume periphery extraction wells. This has been scheduled to give the aquifer time to recover from
the pumping condition.
Sampling of ground-water and surface water will require approximately three weeks to complete.
4.4 Data Evaluation
The data collected during the short-term ground-water elevation measurements will be evaluated to gauge the
immediate response of the aquifer to the non-pumping conditions.
The ground-water quality data collected will be compiled and compared to the ground-water quality data collected
during the extraction well pumping. At monitoring wells where historical data are available, post-pumping ground-
water quality data will be evaluated in the framework of all available data. Results from the natural attenuation
parameter sampling will be evaluated to postulate the processes by which constituents of concern may be degrading.
The data evaluation will require approximately one month to complete following receipt of the analytical data from
the laboratory. The analytical results will be requested on standard turn-around time and should be received one
month after submittal to the laboratory.
4.5 Remedy Evaluation Report
Upon completion of the data evaluation, a Remedy Evaluation Report will be prepared and submitted to the USEPA.
The report will describe the field activities and discuss any deviations from the methods presented in this plan. The
repor1 will also present the data collected during the field activities and the analyses performed on the data, including
discussions on the aquifer response to non-pumping conditions, current ground-water quality in the area between the
TAES and PPES, and natural attenuation processes which may be occurring in the ground water on-Site to mitigate
impacts.
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This report will be submitted to the USEPA two months after the receipt of the analytical data from the ground-water
and surface water sampling events.
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Table 1
Welts Included in Plume Periphery Extraction System
Remedy Evaluation Monitoring Program
National Starch & Chemical Company
Cedar Springs Road Plant
Salisbury, North Carolina
Well ID Well Tvne
WELLS BETWEEN TRENCH AREA AND PLUME
PERIPHERY EXTRACTION SYSTEMS
NS-5 Saprolite Monitorinn Well
NS-6• Transition Zone Monitorina Well
NS-7 Sa□rolite Manitorina Well
NS-8 Saprotite Monitorinn Well
NS-16 Transition Zone Monitorinn Well
NS-17 Transition Zone Monitorina Well
NS-21• Transition Zane Monitorina Well
NS-22• Transition Zone Monitorinn Well
NS-23 Transition Zone Monitorina Well
Ns-25• Transition Zone Monitorina Well
NS-26• Transition Zone Monitorinn Well
NS-27 Transition Zone Monitorina Well
NS-28 Transition Zone Monitorin□ Well
WELLS INCLUDED AS PART OF OU1 MONITORING
PROGRAM
Ns-29• Bedrock Monitorina Well
NS-30 Bedrock Monitorina Well
NS-31 • Transition Zone Monitorinn Well
NS-32 Transition Zone Monitorina Well
EX-01 Bedrock Extraction Well
EX-02 Bedrock Extraction Well
EX-03 Bedrock Extraction Well
EX-04 Bedrock Extraction Well
WELLS INCLUDED AS PART OF OU2 MONITORING
PROGRAM
NS-9 Transition Zone Monitorina Well
NS-10 Saprolite Monitorinn Well
NS-11 Sa□rotite Monitorina Well
NS-15 Transition Zone Monitorina Well
• -Wells at which natural attenuation parameters will be
sampled
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SOURCES:
ROWAN MILLS, CHINA GROVE,
NORTH CAROLINA
7.5 MINUTE QUADRANGLE
CONTOUR INTERVAL= 10 FEET
05/99 EMN
05791596.cdr
05061.002.21
QUADRANGLE LOCATION
51/J"
98 MIL
UTM GR ID AND 'a 987 MAGNETIC NORTH
DECLINATION AT CENTER OF SHEET
2000' 0 2000'
Approximate Scale: 1" = 2000'
NATIONAL STARCH AND CHEMICAL COMPANY
CEDAR SPRINGS ROAD PLANT
SALISBURY, NORTH CAROLINA
SITE LOCATION MAP
BBL BLASIAND, BOUCK & LEE, INC.
engineers & scientists
FIGURE
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~, NSCIJ1.Dl'.G
• P-4
L: OfF•"IBREAKU'IES, •j1, •f:?. "ICONST•, "/PATT"
P: STD-PCP/OL I -'-lNE 8. 1999 CRA-62-SEK, \',ol)N
05-0/0c,05 700\ \0505551.13.0'M,
\
• P-2
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LEGEND
e MONITORING WELL LOCATION
♦ EXTRACTION 'M::LL LOCATION
SOURCES:
AP ENTITLED •s1TE MAP' PREPARED FOR NATIONAL STARCH
~ND CHEMICAL COMPANY BY INTERNATIONAL TECHNOLOGY
CORPORA110N, KNOX'v1LLE, TENN., DATED 5/18/93.
MONITORING WELL SURVEY BY SCHULENBERGER SURVEYING COMPANY, SALISBURY, N.C., DATED 1/21/97
MONITORING Vi'ELL SURVEY BY TAYLOR WEISMAN & TAYLOR, RALEIGH N.C., DATED 3/98
..,.
SCALE IN FEET
NATIONAL STARCH AND CHEMICAL COMPANY
CEDAR SPRINGS ROAD PLANT, SALISBURY, NORTH CAROLINA
REMEDY EVALUATION PLAN FOR
OPERABLE UNIT ONE
SITE MAP
I
FIGURE BBL BLASL.AND, BOUCK & LEE, _INC. 2
engineers & sc1enf1sfs
•-----------------.
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WELL CASING GROUND SURFACE
, '1 TRANSITION f ZONE '' I'-...._ FRACTURE
,/4
BEDROCK
LEGEND
~ UNSATURATED
AREA
• • • •!l• WATER ELEVATION
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TYPICAL PLUME PERIPHERY EXTRACTION WELL
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X: NONE
L: OFF•REF'
JJNE B, 1999 CRA-62-V.ON
0::i0\0::iOB1002\0~1N01.0WG I P: STD-PCP/AP
NOT TO SCALE
NATIONAL STARCH & CHEMICAL COMPANY
CEDAR SPRINGS ROAD PLANT, SALISBURY, NORTH CAROLINA
REMEDY EVALUATION PLAN FOR
OPERABLE UNIT ONE
PLUME PERIPHERY EXTRACTION WELL
CONCEPTUAL MODEL
RRL BLASLAND, BOUCK & LEE, INC, I FIGURE .-...-uiL.,j• engineers &-scientists 3
--·-----Task Name
Approval of Remedy Evaluation Plan
Cecessation of Plume Periphery Well Pumping
Ground-Water Elevation Measurements
Short Term
Long Tenn
Ground-Water and Surface Water Sampling
Reciept of Analytical Data
Data Evaluation
Submittal of Remedy Evaluation Report
Figure 4 -Schedule
Duration
1d
1d
110d
3d
I 110d
< 15d
1d
30d
1d
Remedy Evaluation Plan, Plume Periphery Extraction System
---Month 2
4 5 6 7
National Starch & Chemical Company, Cedar Springs Road Plant. Salisbury, North Carolina
-- --------Month 3 Month 4 Month 5 Month 6 Month 7 Month 8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
Page 1
Task
Progress
Milestone
Summary
~lil~ijj~il,,~I'~' ===·-·\~i'j Rolled Up Task
♦ • •
Rolled Up Milestone ◊
Rolled Up Progress