Final Report

Pilot Region-Based Optimization
 Program for Fund-Lead Sites
       in EPA Region 3

   Site Optimization Tracker:
     Havertown PCP Site
   Havertown, Pennsylvania

          EPA Region III
                 o

-------
               Solid Waste and        EPA 542-R-06-006J
               Emergency Response     December 2006
               (5102P)             www.epa.gov
Pilot Region-Based Optimization Program
   for Fund-Lead Sites in EPA Region 3

       Site Optimization Tracker:
           Havertown PCP Site
        Havertown, Pennsylvania

               EPA Region III

-------
Site Optimization Tracker

  Havertown PCP Site
Havertown, Pennsylvania
      EPA Region III
       December 30, 2005

-------
         SECTION 1:



CURRENT SITE INFORMATION FORM

-------
Date:    12/30/05        Filled Out By:     GeoTrans, Inc.
A. Site Location, Contact Information, and Site Status
1. Site name 2. Site Location (city and State) 3. EPA Region
Havertown PCP Site Havertown, Pennsylvinia 3
4a. EPA RPM 5a. State Contact
Jill Lowe
4b. EPA RPM Phone Number 5b. State Contact Phone Number
215-814-3123
4c. EPA RPM Email Address 5c. State Contact Email Address
lowe.jill@epa.gov
5. Is the ground water remedy an interim remedy or a final remedy? Interim [XI Final I I
6. Is die site EPA lead or State-lead with Fund money? EPA ^ State O

B. General Site Information
la. Date of Original ROD for Ground Water Remedy
9/30/91 (interim remedy)
2a. DateofO&F
Projected for December 2008
3 . What is the primary goal of the P&T system
(select one)?
1 1 Contaminant plume containment
1 I Aquifer restoration
1X1 Containment and restoration
1 I Well-head treatment
lb. Dates of Other Ground Water Decision Documents (e.g., ESD. ROD Amendment)
NA
2b. Date for transfer to State
Projected for 2018
4. Check those classes of contaminants that are
contaminants of concern at the site.
£3 VOCs (e.g., TCE, benzene, etc.)
£3 SVOCs (e.g., PAHs, PCP, etc.)
1 1 metals (e.g., arsenic, chromium, etc.)
1 I other
5. Has NAPL or evidence of NAPL been observed at the site? Yes 1X1 No I I
6. What is the approximate total pumping rate? ~25 gpm
7. How many active extraction wells 1 ,
(or trenches) are there? L trencn
9. How many samples are collected
from monitoring wells or piezometers _ _ „»
each year? (e.g., 40 if 10 wells are
sampled quarterly)
1 1 . What above-ground treatment processes are usec
1 I Air stripping
IXI Carbon adsorption
IXI Filtration
1 | Off-gas treatment
| 	 | Ion exchange
8. How many monitoring wells are _»
regularly sampled? ~
10. How many process monitoring samples
(e.g., extraction wells, influent, effluent, etc.) ,„
are collected and analyzed each year? (e.g., 24
if influent and effluent are sampled monthly)
(check all that apply)?
IXI Metals precipitation
I | Biological treatment
£3 UV/Oxidation
I | Reverse osmosis
O Other
12. What is the approximate percentage of system downtime per year? 10% | | 10 - 20% ^\| >20% | |

-------
C. Site Costs
1. Annual O&M costs
O&M Category
Labor: project management, reporting,
technical support
Labor: system operation
Labor: ground water sampling
Utilities: electricity
Utilities: other
Consumables (GAC, chemicals, etc.)
Discharge or disposal costs
Analytical costs
Other (parts, routine maintenance, etc.)
O&M Total
Actual1 Annual
Costs for FY04
$57,000
$170,000
$82,000
$68,000
$12,000
$87,000
$56,000
$40,000***
$60,300
$632,300
Estimated Annual
Costs for FY052
$60,000
$175,000
$82,000
$50,000*
$12,000
$75,000**
$58,000**
$40,000***
$63,000
$615,000
Estimated Annual
Costs for FY063
$60,000
$175,000
$82,000
$50,000*
$12,000
$50,000**
$29,000**
$40,000***
$63,000
$561,000
The O&M total should be equal to the total O&M costs for the specified fiscal years, including oversight from
USAGE or another contractor. For costs that do not fit in one of the above cost categories, include them in the
"Other " category. If it is not possible to break out the costs into the above categories, use the categories as best
as possible and provide notes in the following box.
2. Non-routine or other costs
$30,000
$63,000
$63,000
Additional costs beyond routine O&M for the specified fiscal years should be included in the above spaces.  Such
costs might be associated with additional investigations, non-routine maintenance, additional extraction wells, or
other operable units. The total costs billed to the site for the specified fiscal years should be equal to the O&M
total plus the costs entered in item 2.
Notes on costs:

    1.   Costs, with the exception of the analytical costs, were provided by the RPM.

    2.   FY05 and FY06 costs were estimated by the ROET based on the RPM projections and discussion during
        the optimization follow-up meetings.

Ground water sampling labor also includes shipment of samples, sampling supplies, rental of equipment, and
travel expenses.

Utilities Others: Includes mowing and snow removal

Disposal Costs: Includes sludge disposal only

Non-routine costs are for plant improvement and do not reflect the costs of additional investigation or the
installation/testing of new extraction wells.

* Decrease in electricity costs represents the use of one UV/oxidation unit instead of two.

** Decreases in consumables and disposal are associated using one UV/oxidation unit instead of two and
decreasing the amount of ferric sulfate (which decreases costs and the amount of sludge produced).

*** Analytical costs were estimated by the ROET based on the sampling program.  The analytical costs are not
incurred by the EPA site team because the samples are analyzed by the CLP program. However, analytical costs
similar to those estimated by the ROET, will likely be incurred by the State when the site is transferred to the
State after LTRA.

-------
D. Five-Year Review
1. Date of the Most Recent Five-Year Review
2. Protectiveness Statement from the Most Recent Five-Year Review
    I  |   Protective                               I  I   Not Protective

    |	|   Protective in the short-term                 |	|   Determination of Protectiveness Deferred

3. Please summarize the primary recommendations in the space below
E. Other Information
If there is other information about the site that should be provided please indicate that information in the space
below.  Please consider enforcement activity, community perception, technical problems to be addressed, and/or
areas where a third-party perspective may be valuable.

The site team continues to investigate the site and determine an appropriate final remedy while
continuing to operate and improve the treatment plant associated with the operating interim
P&T system.
The contaminant plume was delineated in 2005, and current efforts are focused on determining
an appropriate extraction system for a final remedy.

-------
                            SECTION 2:

               FOLLOW-UP HISTORY AND SUMMARIES
Note: Follow-up summaries are provided in reverse chronological order and include updated
and/or new recommendations.

-------
                              FOLLOW-UP HISTORY
 Date of Original Optimization Evaluation
            August 5, 2003 (Evaluation meeting)
            March 4, 2004 (Final Report)	
           Meeting Date
          December 16, 2004
           October 18, 2005
 Report Date
Item
 March 14, 2005      Follow-Up #1 (conducted as part of pilot project)


December 30, 2005    Follow-Up #2 (conducted as part of pilot project)


                   Follow-Up #3


                   Follow-Up #4


                   Follow-Up #5


                   Follow-Up #6


                   Follow-Up #7


                   Follow-Up #8
"x" in box indicates the item has been completed

-------
                  SUMMARY OF FOLLOW-UP #2
Site or System Name
Date of This Follow-Up Summary
Date of Follow-Up Meeting or Call
(Indicate if Meeting or Call)
Havertown PCP Site
December 30, 2005
October 18, 2005 - Meeting
ROET MEMBERS CONDUCTING THE FOLLOW-UP EVALUATION:
Name
Norm Kulujian
Kathy Davies
Peter Ludzia
Eric Johnson
Peter Rich
Rob Greenwald
Doug Sutton
Kathy Yager
Chuck Sands
Affiliation
U.S. EPA Region 3
U.S. EPA Region 3
U.S. EPA Region 3
U.S. EPA Region 3
GeoTrans, Inc.
GeoTrans, Inc.
GeoTrans, Inc.
U.S. EPAOSRTI
U.S. EPA OSRTI
Phone
215-814-3130
215-814-3315
215-814-3224
215-814-3313
410-990-4607
732-409-0344
732-409-0344
617-918-8362
703-603-8857
Email
lailujian.norm@iepa.gov
davies.kathv@epa.gov

ludzia.peter@epa.gov
johnson.eric@epa.gov
prich@geotransinc.com
rgreenwald@geolransinc.com
dsulton@geolransinc.com
yager.katlileen@iepa.gov
sands.charles@epamail.epa.gov
SITE TEAM MEMBERS (INCLUDING CONTRACTORS) INTERVIEWED
Name
Jill Lowe
Mindi Snoparsky
Harish Mital (by phone)
Affiliation
U.S. EPA Region 3 (RPM)
U.S. EPA Region 3 (Hydro)
Terra Tech (contractor)
Phone
215-814-3123
215-814-3316
302-738-7551
Email
1 o we . i i 11 @epa . go v
Snoparsky . mindi@epa.gov
lrarish.mital@telralech.com

-------
IMPLEMENTATION STATUS OF ALL RECOMMENDATIONS UNDER CONSIDERATION BUT NOT
PREVIOUSLY IMPLEMENTED
  Recommendation
E-6.1.1 Properly Seal Abandoned 12-Inch Sewer Line and Remediate Surface Soils
Near the Seep	
  Recommendation
       Reason
Effectiveness
Implementation
    Status
Alternative Implemented
 Comments:  The site team has plugged the entire abandoned sewer line and has conducted an investigation of the
 Residential Open Space (ROS) area near the seep, including 15 borings with shallow and deep soil samples plus
 ground water samples. The site team noted that concentrations were not high enough to warrant removal because
 they are more than 8 feet below ground surface. Ground water contamination associated with this area appears to
 have migrated northward toward the original plume.
Recommendation
Recommendation
Reason
E-6.1.2 Improve Plume Delineation to the South and Vertically
Effectiveness
Implementation
Status
Implemented
 Comments:  The site team has installed additional wells since the last follow-up meeting, completing the
 horizontal and vertical delineation of the plume.
Recommendation
Recommendation
Reason
E-6.1.3 Evaluate Plume Capture Once Plume is Deh'neated
Effectiveness
Implementation
Status
Substantial Progress
 Comments: The site team lias completed delineation of the plume and can now evaluate capture.  The site team
 developed a ground water model to evaluate capture, but in technical assistance provided as a result of the
 previous follow-up meeting, the ROET determined that the model was not calibrated correctly and is not
 appropriate for evaluating capture at this stage. The site team will recalibrate the model using data from pump
 tests, including a pump test on a new extraction well in the source area that will be labeled RW-5.
Recommendation
Recommendation
Reason
E-6.2.2 Evaluate Areas to Reduce Labor Costs
Cost Reduction
Implementation
Status
Will be implemented
 Comments:  Labor costs will be reevaluated once the final extraction and treatment systems are operating.
  Recommendation
E-6.3.1 Continue Improving Treatment Plant to Facilitate Operation and Potentially
Increase Capacity	
  Recommendation
       Reason
Technical Improvement
Implementation
    Status
In progress/Ongoing
 Comments: The site team continues to make improvements to the treatment plant. The specific recommendation
 to increase the capacity of the first metals removal tank has not been implemented, but may be considered,
 particularly if a higher flow rate is required due to increased extraction.  The ferric sulfate addition has been
 reduced from 200-250 ppm to approximately 50 ppm, resulting in smoother operation of the metals removal
 system, reduced chemical usage, and approximately 50% less sludge production.

-------
 Recommendation
E-6.4.1 Adapt P&T System to Focus Primarily on Cost-Effective Containment with
Decreased Emphasis on Restoration
 Recommendation
      Reason
Site Close-out
Implementation
     Status
Under Consideration
Comments:  This recommendation will be taken into consideration as the site moves forward with the final
remedy. During the meeting, the site team indicated that they see pumping from a new extraction well (to be
labeled RW-5) as a primary component of the extraction system because of die high yield (approximately 30
gpm) and high concentrations (5 to 8 mg/L).  Another component of the extraction system may be another
extraction well (to be labeled RW-6) to be located near, but deeper than the recovery trench.
Recommendation
Recommendation
Reason
E-6.4.2 Potential Options for Improving Capture
Site Close-out
Implementation
Status
Considered
Comments: The site team is considering various options for improving capture, including those mentioned in the
recommendation.
Recommendation
Recommendation
Reason
1F-1 Recalibrate the Site Ground Water Model
Protectiveness
Implementation
Status
Under Consideration
Comments: The ground water flow model will be a valuable tool for evaluating various extraction scenarios, but
as discussed in the technical assistance appendix, the review of the model by the evaluation team suggests that
further model calibration is needed prior to using the model to evaluate capture zones.
 Recommendation
1F-2 Manually Recover Product from New Source Area Wells to Evaluate Potential
for Long-Term Product Recovery
 Recommendation
      Reason
Site Close-out
Implementation
     Status
Under Consideration
Comments:  The site team did not report on product recovery during the recent follow-up meeting. Rather, it
focused on reporting the high yield and concentration at the new extraction well (to be labeled RW-5).
Recommendation
Recommendation
Reason
1F-3 Continue Delineation Efforts
Protectiveness
Implementation
Status
Implemented
Comments: See comments under E-6. 1.2.
      Key for recommendation numbers:
         *  E denotes a recommendation from the original optimization evaluation
         *  Fl,  F2, etc. denote recommendations from the first, second, etc. follow-up meeting
         •  The number corresponds to the number of the recommendation as stated in the optimization
             evaluation or follow-up summary where the recommendation was provided

-------
RECOMMENDATIONS PREVIOUSLY IMPLEMENTED OR THAT WILL NOT BE IMPLEMENTED
Recommendation
Recommendation
Reason
E-6.1.4 Take Measures to Further Reduce System Downtime
Effectiveness
Implementation
Status
Implemented/Ongoing
 Comments: The operation of the treatment plant has significantly improved due to internal optimization efforts.
 The system influent is routinely 28 to 30 gpm. The main system components, however, are treating ~40 gpm due
 to recycling/backwash within the plant.
Recommendation
Recommendation
Reason
E-6.2.1 Use Fewer UV/Oxidation Units
Cost Reduction
Implementation
Status
Implemented/Ongoing
 Comments:  The site team lias shut off all but one of the UV/Oxidation units, and the treatment plant still
 effectively meets standards.  The site team is considering a pilot test using just GAC as treatment for organics, but
 there have been problems with the recovery wells that have detracted from moving forward with this pilot test.
 The site team will likely wait until additional extraction wells are brought on line before further considering the
 GAC-only treatment for organics.  The change is resulting in annual cost savings of approximately $35,000 per
 year.
Recommendation
Recommendation
Reason
E-6.3.2 Make Piping Changes to Better Use the Second Equalization Tank
Technical Improvement
Implementation
Status
Implemented
 Comments: This recommendation lias not been implemented, but an alternative, which includes converting the
 free product storage tank into a wastewater storage tank has been implemented. This has facilitated system
 operation.
       Key for recommendation numbers:
         • E denotes a recommendation from the original optimization evaluation
         • Fl, F2, etc. denote recommendations from the first, second, etc. follow-up meeting
         • The number corresponds to the number of the recommendation as stated in the optimization
             evaluation or follow-up summary where the recommendation was provided
OTHER CHANGES, UPDATES, OR SIGNIFICANT FINDINGS SINCE LAST FOLLOW-UP
       The primary new finding by the site team is the high yield and high concentrations at a
       new source area extraction well (to be labeled RW-5).  The well can yield approximately
       30 gpm and has concentrations as high as 5 to 8 mg/L. The site team has considered
       making this well a primary component of the extraction system.

       The Philadelphia Chewing Gum plant has moved locations.  The property may be
       redeveloped into a municipal complex with a library.

-------
NEW OR UPDATED RECOMMENDATIONS FROM THIS FOLLOW-UP

       1.  Make recalibrating the Model a Priority and Use the Calibrated Model for Selecting
          an Appropriate Extraction System for the Final Remedy

          In technical assistance provided as part of the previous follow-up summary, the
          ROET indicated that the ground water model developed for the site had not been
          calibrated appropriately and that any conclusions derived from this model regarding
          capture zones and/or contaminant transport should be viewed with extreme
          skepticism. The ROET reemphasizes the need to recalibrate the model so that it can
          be used for evaluating various extraction scenarios, including extraction from the new
          extraction wells (to be labeled RW-5 and RW-6). Although the site team should
          consider optimizing the treatment plant, the ROET believes that various extraction
          scenarios should be evaluated through model scenarios before making any significant
          and/or costly improvements to the treatment system. Modeling will help the site team
          determine the appropriate distribution of pumping from the existing recovery trench,
          the existing extraction wells, and the future extraction wells (to be labeled RW-5 and
          RW-6).

          Although pumping from RW-5 can significantly increase mass removal, the ROET
          cautions against excessive pumping from RW-5 if this pumping does not contribute
          to providing the desired plume capture and limits pumping at other wells that are
          more important for plume capture (due to treatment plant capacity limits). The site
          will likely remain impacted for several decades regardless of the mass recovery
          afforded by a P&T system. Therefore, if the site team focuses on mass removal, it
          could increase costs without substantially improving protectiveness or shortening the
          remedy lifetime, especially if source removal requires significant modifications to the
          treatment system that would otherwise not be needed.
       2.  Track Costs of P&T O&M and other Site Activities Separately

          Operation of the interim P&T system has continued as the site team has continued to
          investigate the site.  As a result, it can be quite easy for the costs of P&T O&M to
          blend with costs for other site activities, especially in categories such as ground water
          monitoring, project management, and reporting.  The ROET encourages the site team
          to track the costs of P&T O&M separately from the costs of other site activities.  This
          separate tracking will help the site team better estimate the costs of P&T operation as
          a final remedy.

-------
                  SUMMARY OF FOLLOW-UP #1
Site or System Name
Date of This Follow-Up Summary
Date of Follow-Up Meeting or Call
(Indicate if Meeting or Call)
Havertown PCP Site
March 14, 2005
December 16, 2004 - Meeting
ROET MEMBERS CONDUCTING THE FOLLOW-UP EVALUATION:
Name
Norm Kulujian
Peter Schaul
Peter Rich
Rob Greenwald
Doug Sutton
Jean Balent (by phone)
Chuck Sands
Affiliation
U.S. EPA Region 3
U.S. EPA Region 3
GeoTrans, Inc.
GeoTrans, Inc.
GeoTrans, Inc.
U.S.EPAOSRTI
U.S. EPA OSRTI
Phone
215-814-3130
215-814-3183
410-990-4607
732-409-0344
732-409-0344
703-603-9924
703-603-8857
Email
lailujian.normffiiepa.gov
schaul.peterffi.epa.gov
prichs'fligeotransinc.com
rgreenwaldffigeotransinc.com
dsuttonffi'.geotransinc.com
balent.jeanffiepaniail.epa.eov

sands.cliarlesffiepamail.epa.gov
SITE TEAM MEMBERS (INCLUDING CONTRACTORS) INTERVIEWED
Name
Jill Lowe
Mindi Snoparsky
Harish Mital (by phone)
Affiliation
U.S. EPA Region 3 (RPM)
U.S. EPA Region 3 (Hydro)
Terra Tech (contractor)
Phone
215-814-3123
215-814-3316
302-738-7551
Email
lowe.jillffiiepa.gov
Snoparsky . miiidiffiepa.gov
harish.mitalffitetratech.com

-------
IMPLEMENTATION STATUS OF PREVIOUSLY IDENTIFIED RECOMMENDATIONS
Recommendation
Recommendation
Reason
6.1.1 Properly Seal Abandoned 12-Inch Sewer Line and Remediate Surface Soils
Near the Seep
Effectiveness
Implementation
Status
Significant progress
 Comments: The site team has plugged the entire abandoned sewer line and has conducted an investigation of the
 Residential Open Space (ROS) area near the seep, including 15 borings with shallow and deep soil samples plus
 ground water samples. Most were contaminated above removal levels. As of the follow-up meeting, the site team
 was awaiting the results of additional samples.
Recommendation
Recommendation
Reason
6.1.2 Improve Plume Delineation to the South and Vertically
Effectiveness
Implementation
Status
Significant Progress
 Comments: The site team has installed new wells (CW-16D, CW-17D, CW-18D, C W-19D, CW20-S, and
 CW20-D) in five locations that are consistent with the optimization evaluation recommendations. However, the
 results do not provide complete horizontal or vertical delineation of the plume. The site team will need to install
 additional wells, which is planned for the Summer of 2005.
Recommendation
Recommendation
Reason
6.1.3 Evaluate Plume Capture Once Plume is Delineated
Effectiveness
Implementation
Status
Significant Progress
 Comments: The contaminant plume has not yet been fully delineated, so the capture zone cannot be effectively
 analyzed yet. The site team has constructed a three-dimensional ground water flow model and has conducted a
 preliminary capture zone analysis using particle tracking. The simulations suggest that the existing recovery
 system captures the known extent of dissolved contamination upgradient of the trench, but both the model and the
 analysis require further evaluation.  The optimization evaluation team has reviewed the modeling report and
 preliminary capture zone analysis as part of the technical assistance task for the optimization project. Comments
 on the report are included in Appendix B.  The independent review of the model recommends  that further
 calibration be performed prior to using the model to evaluate capture zones. The Remedial Investigation is
 scheduled for completion during the Summer of 2005.  The capture zone will be further evaluated at that time.
Recommendation
Recommendation
Reason
6.1.4 Take Measures to Further Reduce System Downtime
Effectiveness
Implementation
Status
Completed/Ongoing
 Comments: The operation of the treatment plant has significantly improved due to internal optimization efforts.
 The system influent is routinely influent of 28 to 30 gpm. The main system components, however, are treating
 ~40 gpm due to recycling/backwash within the plant.
Recommendation
Recommendation
Reason
6.2.1 Use Fewer UV/Oxidation Units
Cost Reduction
Implementation
Status
Completed/In progress
 Comments:  The site team lias shut off all but one of the UV/Oxidation units, and the treatment plant still
 effectively meets standards.  The site team is considering a pilot test using just GAC as treatment for organics, but
 there have been problems with the recovery wells that have detracted from moving forward with this pilot test.
 The site team will likely wait until additional extraction wells are brought on line before further considering the
 GAC-only treatment for organics.

-------
Recommendation
Recommendation
Reason
6.2.2 Evaluate Areas to Reduce Labor Costs
Cost Reduction
Implementation
Status
To be implemented
 Comments: Labor costs will be reevaluated once the final extraction and treatment systems are operating.
Recommendation
Recommendation
Reason
6.3.1 Continue Improving Treatment Plant to Facilitate Operation and Potentially
Increase Capacity
Technical Improvement
Implementation
Status
In progress
 Comments: The site team continues to make improvements to the treatment plant. The specific recommendation
 to increase the capacity of the first metals removal tank has not been implemented, but may be considered,
 particularly if a higher flow rate is required due to increased extraction.
Recommendation
Recommendation
Reason
6.3.2 Make Piping Changes to Better Use the Second Equalization Tank
Technical Improvement
Implementation
Status
Completed
 Comments: This recommendation lias not been implemented, but an alternative, which includes converting the
 free product storage tank into a wastewater storage tank lias been implemented.  This has facilitated system
 operation.
Recommendation
Recommendation
Reason
6.4.1 Adapt P&T System to Focus Primarily on Cost-Effective Containment with
Decreased Emphasis on Restoration
Site Close-out
Implementation
Status
Under Consideration
 Comments: This recommendation will be taken into consideration as the site moves forward with the final
 remedy.
Recommendation
Recommendation
Reason
6.4.2 Potential Options for Improving Capture
Site Close-out
Implementation
Status
Under Consideration
 Comments: This recommendation stems from the potential need to improve capture downgradient of the trench.
 The optimization evaluation suggested potential alternatives to addressing downgradient contamination.  The site
 team is beginning to look at potential alternatives. The ground water flow model will be a valuable tool for such
 evaluations, but as discussed in below and in Appendix A, the review of the model by the evaluation team
 suggests that further model calibration is needed prior to using the model to evaluate capture zones.
OTHER CHANGES, UPDATES, OR SIGNIFICANT FINDINGS SINCE LAST FOLLOW-UP

    •  The Philadelphia Chewing Gum plant has moved locations.  The property may be
       redeveloped into a municipal complex with a library.

    •  The site team has conducted a number of investigation activities that are consistent with
       the optimization evaluations. Although it was hoped that the suggestions made in the
       optimization evaluation would be sufficient to delineate the plume, it is apparent that
       additional investigation is needed.

-------
       Site institutional controls have not been addressed yet.

       Installation of CW-16D at the Young's Produce property revealed substantial free
       product prompting the need for additional product delineation, containment, and recovery
       efforts.
NEW OR UPDATED RECOMMENDATIONS FROM THIS FOLLOW-UP

    1.   A review of the modeling report is attached as Appendix A. This review indicates an
       overriding concern that the model calibration process appears to be significantly flawed,
       and any conclusions derived from this model regarding capture zones and/or contaminant
       transport  should be viewed with extreme skepticism.  As such, the optimization
       evaluation team recommends revisiting the model calibration and improving the model so
       that it will be a useful tool for making site decisions.  The attached review provides a
       number of specific comments that can be considered in redeveloping the model. The
       optimization evaluation team could provide additional information with respect to model
       development or potentially assist with the development of the model as part of the
       technical  assistance task for this project.  The evaluation team estimates that the
       additional model development and calibration might cost up to  $20,000, including any
       assistance that might be provided by the evaluation team.

    2.   The optimization evaluation team recommends that the site team recover product from
       the new well near Young's Produce and from other wells near the source area (e.g., NW-
       6-81, R-2, HAV-02, NW-1-81). This product recovery could be done manually on a
       monthly basis for approximately six months to gather information on recovery volumes
       to determine whether skimming pumps or continuing manual recovery would be
       appropriate for interim removal. This information could be considered along with other
       site data when developing the final  remedy and any future modifications that will be
       made to the treatment plant.  At this point, the optimization evaluation team discourages
       the use of the P&T system to also act as a product recovery system. Total fluids pumping
       in the source area should be suspended until containment of the dissolved plume is
       achieved  and the treatment system operation is stable.  At that point source area mass
       removal options including pumping could be reevaluated.  This temporary product
       recovery might cost $20,000 (including disposal, but excluding reporting).

    3.   The optimization evaluation team also recommends that the site team continue its
       investigation activities to better delineate the plume both horizontally and vertically.
       Specific feedback from the optimization evaluation team on suggested investigation
       activities  and conceptual model development will be provided in a separate technical
       assistance document, to be provided before the next followup meeting.

-------
Updated Cost Summary Table
Recommendation
Reason
Implementation
Status
Estimated
Capital Costs
($)
Actual Capital
Costs
($)
Estimated Change
in Annual Costs
(S/yr)
Actual Change in
Annual Costs
($/y)
Original Optimization Evaluation Recommendations
6.1.1 Properly Seal
Abandoned 12-Inch Sewer Line
and Remediate Surface Soils
Near the Seep
6.1.2 Improve Plume
Delineation to the South and
Vertically
6.1.3 Evaluate Plume
Capture Once Plume is
Delineated
6.1.4 Take Measures to
Further Reduce System
Downtime
6.2.1 Use Fewer
UV/Oxidation Units
6.2.2 Evaluate Areas to
Reduce Labor Costs
6.3.1 Continue Improving
Treatment Plant to Facilitate
Operation and Potentially
Increase Capacity
6.3.2 Make Piping Changes
to Better Use the Second
Equalization Tank
Effectiveness
Effectiveness
Effectiveness
Effectiveness
Cost Reduction
Cost Reduction
Technical
Improvement
Technical
Improvement
Alternative
Implemented
Implemented
Substantial
Progress
Implemented/
Ongoing
Implemented/
Ongoing
Will be
implemented
In progress/
Ongoing
Implemented
$200,000
$120,000
to
$150,000
$55,000
$0
$0
$0
<$ 10,000
to
$25,000
$10,000
Not quantified*
Not quantified*

Not quantified*
$0


Not quantified*
$0
$5,000
$0
$0
($32,000)
($40,000)
$0
$0
$0
Not quantified*

Not quantified*
($35,000)


Not quantified*

-------
Recommendation
Reason
Implementation
Status
Estimated
Capital Costs
($)
Actual Capital
Costs
($)
Estimated Change
in Annual Costs
(s/yr)
Actual Change in
Annual Costs
(S/yr)
Original Optimization Evaluation Recommendations (continued)
6.4. 1 Adapt P&T System to
Focus Primarily On Cost-
Effective Containment with
Decreased Emphasis on
Restoration
6.4.2 Potential Options for
Improving Capture
Site Closeout
Site Closeout
Under
Consideration
Considered
$0

($30,000)

No costs associated with this recommendation
New or Updated Recommendations from Follow-up #1, December 16, 2004
1 . Redevelop ground water
model
2. Temporary manual recovery
of product
3. Continue investigation
Effectiveness
Effectiveness
Effectiveness
Under
Consideration
Under
Consideration
Implemented
$20,000
$20,000
Not quantified*



$0
$0
Not quantified*



Costs in parentheses imply cost reductions.
    *    Indicates costs or savings ha\'e not been estimated independently of other site activities that ha\>e occurred since the optimization evaluation.

-------
                          APPENDIX: A



   ARCHIVE OF TECHNICAL ASSISTANCE PROVIDED BY THE ROET
Note: Technical assistance items are provided in reverse chronological order.

-------
                              Technical Assistance Item #1
                                Presented March 7, 2005

Comments on the Ground Water Modeling Report

GeoTrans was asked to provide a technical review of the "Groundwater Model Report" prepared
by Val F. Britton, revision dated July 29, 2004.  The report was reviewed by Rob Greenwald and
Pete Andersen. Based on our review, the overriding concern is that the model calibration
process appears to be significantly flawed, and any conclusions derived from this model
regarding capture zones and/or contaminant transport should be viewed with extreme skepticism.
Some specific comments are provided below.

    1)  The vast majority of figures are extremely difficult to read or interpret.  All of the "three-
       dimensional" figures (such as Figures 1 to 4) present information in a manner that cannot
       be understood by the reader. For many of the other figures, the use of a colored
       background and/or excessive background features makes it impossible for the reader to
       discern information. Much of the text on the figures is not legible. The use of
       "perspective views" rather than pure map view (i.e., looking straight down) on many
       figures makes it very difficult to interpret the figures.

    2)  The basis for the model layering is not clearly presented. The model has six layers, but
       there is no real explanation or basis for the having five additional layers below layer 1, all
       of which are assigned the same properties. In contrast, layer 1  lumps saprolite and
       bedrock.  It is not clear why a two-layer model (saprolite and bedrock) was not
       considered.

    3)  The approach to model calibration appears to be significantly flawed. As described in
       Section 2.0, the water table measurements used for model calibration were for a non-
       pumping condition.  It is generally poor practice to calibrate a flow model to just a non-
       pumping condition without also calibrating it to one or more stressed (i.e., pumping)
       conditions. This is because the simulation of a stress (such as pumping) and the
       evaluation of the related drawdown response is the best way to calibrate aquifer
       parameters such as hydraulic conductivity. In the model described in the report, there
       will be little or no variation in heads due to variation in hydraulic parameters, especially
       if the drains are assigned a high value of conductance and thus act like a specified head.
       If that is the case (which we expect it is),  then in the absence of pumping, same values of
       head will generally be  simulated no matter what values of hydraulic conductivity or
       recharge are simulated. The simulated heads will be almost entirely controlled by the
       specified heads along the model boundary and the specified drain levels. That situation
       does not allow for true model calibration to occur. In fact, on page 11 the report author
       acknowledges that the  model was run with a 20% increase and a 20% decrease in net
       recharge,  with no significant impact on simulated heads.  That is consistent with the
       analysis provided here. The proper approach is to calibrate the model to a stressed
       condition, using observed pumping rates, and  comparing simulated water levels (and/or
       flow patterns or flow budgets) to the conditions observed in the field. Ideally, calibrating

-------
   to more than one different set of pumping stresses (by turning some wells off in the field,
   measuring the corresponding water levels, and then simulating that condition in the
   model) adds confidence in the model calibration.

4) The method of evaluating and presenting the results of the calibration is not at all clear.
   On Figures 21-24, there are green and yellow bars of varying lengths each superimposed
   on a line with 3 cross hatches.  There is no explanation as to why some are longer than
   others (assumed that longer means greater error), or how to tell where heads are
   simulated too high versus too low.  On maps such as these, residuals (simulated minus
   observed) should be presented with symbols, not bars, with the residual values clearly
   indicated (including the sign, positive or negative).  The text does not clarify the
   approach used in this study.  It seems to indicate that a 1-foot residual was the target.  It
   then says "the majority of wells fell within a 95% or better match", but does not indicate
   what the 95% refers to (i.e., 95 % of what?). The proper approach is to present a table of
   simulated versus observed values, and to calculate basic statistics such as mean of
   residuals (should be close to zero) and mean absolute error (the mean of the absolute
   value of the residuals), which should generally be within 5 percent of the observed head
   range of the target observations.  Since no such data or statistics are provided, the
   calibration is impossible to assess on this basis.

5) The presentation of drain assignment (Figure 18) and related discussion of flow budgets
   (Table 3 and text on Page 10-11) is also confusing:

       o  It is suspected by  GeoTrans that the conductance values in the unlined drain areas
          were set high enough that the drains act like specified head cells (especially given
          the discussion on  page 10 that indicated high hydraulic conductivity material was
          assumed around the drains).  As previously discussed, this leads to very non-
          unique results regarding calibration of model parameters given the use of an
          unstressed condition.

       o  On Figure 18, it is not clear what the node numbers signify (why include them on
          the figure?).  The  segment numbers are not legible for many of the segments.

       o  Table 3 does not clearly indicate whether the reported flows are observed or
          simulated, but it is assumed they are  simulated values.

       o  In the section on Storm Water Drains and Sanitary Lines, it says "a rate of 1 to 2
          gpm through the drains was utilized.  An exception to this flow rate was the
          abandoned sewer  line (10 gpm)...".  Is this saying these flow rates were
          calibration targets? If so, a comparison with simulated conditions is not
          presented. Or is it suggesting that somehow the flow rates associated with the
          drains was assigned? That is not consistent with the MODFLOW Drain Package,
          which calculates flows in drains based on simulated heads and assigned
          parameters.

       o  The comparison of simulated outflow of Naylors Run (409 gpm) is much greater
          than the measured flow measured downgradient of the "site"  (not quite sure how
          far, 314 gpm). Although such measurements of flow in streams are highly

-------
          uncertain (as properly discussed in the report), it is likely that the simulation of
          too much water discharging to Naylor's run is an indication of poor model
          calibration (too much net recharge in the model).  It is likely that recharge rate in
          the model is too high, but this could not be determined during model calibration
          due to the reasons discussed earlier.

6) No true sensitivity analysis is presented except for changes in net recharge.  As discussed
   earlier, the construction and calibration of this particular model, based on an unstressed
   condition, is not well suited to a sensitivity analysis for model calibration. The proper
   approach is, under stressed conditions, to change key parameter values (including
   hydraulic conductivity, drain elevations and conductance, horizontal anisotropy, vertical
   anisotropy, and perhaps other items such as boundary heads) and to presents maps
   illustrating change in head relative to the base model (i.e., contour the result of base
   model heads versus changed model heads). In that way the spatial impacts of the
   parameter variation can be evaluated. Ideally, sensitivity analysis is also presented for
   model prediction scenarios and not just for model calibration. For instance, the
   horizontal anisotropy (a very difficult parameter to get a handle on  in reality) appears to
   simply be assigned, and likely has a significant impact on model predictions, but it is
   simply not possible for the reader of this report to determine how significant variation in
   this parameter might impact model predictions.

7) The solute transport analysis indicates that concentrations observed at some locations
   cannot be replicated by the model, and suggests this may  indicate additional contaminant
   sources.  GeoTrans notes that this could equally be (or even more likely be) further
   indication of imperfect model calibration.

8) Given these issues, GeoTrans does not believe this model has been sufficiently calibrated
   to be used as a predictive tool.  As such, any conclusions  derived from this model
   regarding capture zones and/or contaminant transport should be viewed with extreme
   skepticism. If further modeling is performed, it is strongly suggested that more thorough
   calibration be performed to one or more stressed conditions, that the calibration be
   presented in a more traditional manner, that sensitivity analysis be performed for multiple
   parameters as part of model calibration, that at least one alternate form of the model with
   different parameters but similar calibration characteristics be used to assess  sensitivity of
   model predictions to parameter uncertainty, and that figures be produced with different
   software using simpler backgrounds and legible text.

-------
                                APPENDIX B:

                 BASELINE SITE INFORMATION SHEET AND
                   OPTIMIZATION EVALUATION REPORT
Note: The attached information sheet was generated during an original nationwide screening
effort in 2000 and 2001 and has a different format than the currently used information sheet
included in Section 1 of this document. The optimization evaluation report that is provided is a
full-scale Optimization Support Evaluation (OSE) funded by the Region in 2003.	

-------
                                                      Havertown POP OU2
                                                       Havertown, PA (Region 3)
                                                      CERCLIS ID PAD002338010

                                                         Contact Information
  RPM
  Gregory Ham
  1650 Arch Street (3HS21)
  Philadelphia, PA 19103-2029
  215-814-3194 (phone)
  215-814-3002 (fax)
  ham.greg@epa.gov
State Regulator
April Flipse
PADEP
555 North Lane, Suite 6010
Conshohocken, PA 19428
610-832-5937 (phone)
610-832-6143 (fax)
Flipse .April@dep.state.pa.us
Contractor
Lori Stoll
URS Corporation
200 Orchard Ridge Drive, Suite 101
Gaithersburg, MD 20878-1978
301-258-9780 (phone)
301-869-2043 (fax)
lori_stoll@urscorp.com
                                                    System Information and Data
Type of Fund-lead Site:
Date original ROD was signed:
Date of last modification to ROD:
Type of ROD:
Status of P&T system:
Primary goal of system:
Presence of NAPLs
Approximate annual O&M costs:
Costs related to monitoring:
Approximate pumping rate:
Result of previous evaluation of
peformance/effectiveness:
EPA-lead
9/30/91

Interim
Being Installed
Containment & Restoration
Observed
$1,000,000
$283,300
45gpm
Not evaluated











Number of extraction wells:
Date of construction completion:
Date of operational and functional:
Expected date of turnover to state:
Expected date of completion:
Approximate downtime per year:
Number of monitoring wells used:
Frequency of sampling:
Is plume migration controlled?
Progress of aquifer restoration:
Difficulty (due to social/political factors) of
implementing minor/major changes:
4
5/2001
4/2002
4/2012
4/2033

15
2 times per year


minor/moderate
                  Contaminants of Concern:
                                                                               Treatment Processes:
                  Benzene and Toluene
                  Dioxin (TCDD equivalents)
                  Pentachlorophenol (PGP)
                  Trichloroethylene (TOE)
                                Metals precipitation
                                Air stripping
                                Biological treatment
                                UV oxidation
                                Carbon adsorption
                                Filtration
                                Ion Exchange
                                Reverse Osmosis
                                Off-gas treatment
                                other/not sure
            yes
                                                                                                       yes
                                                                                                       yes
                                                                                                       yes
Comments:
This system includes a 200 foot long collection trench and four oil/water extraction wells. There is free product (PCP/oil) being recovered from most of the
wells.

-------
          Streamlined
Optimization Evaluation Report

      Havertown PCP Site
   Havertown, Pennsylvania

          EPA Region III
Report of the Optimization Support Evaluation
Site Visit Conducted at the Havertown PCP Site
            August 5, 2003
             Final Report
             March 4, 2004

-------
                                       NOTICE
Work described herein was performed by GeoTrans, Inc. (GeoTrans) for the U.S. Environmental
Protection Agency (U.S. EPA). Work conducted by GeoTrans, including preparation of this report, was
performed under S&K Technologies Prime Contract No. GS06T02BND0723 and under Dynamac
Corporation Prime Contract No. 68-C-02-092, Work Assignment ST-1-08.  Mention of trade names or
commercial products does not constitute endorsement or recommendation for use.

-------
                               EXECUTIVE SUMMARY
An Optimization Support Evaluation (OSE) involves a team of expert hydrogeologists and engineers,
independent of the site, conducting an evaluation of site operations. It is a broad evaluation that
considers the goals of the remedy, site conceptual model, above-ground and subsurface performance, and
site exit strategy. The evaluation includes reviewing site documents, visiting the site for up to 1.5 days,
and compiling a report that includes recommendations to improve the system. Recommendations with
cost and cost savings estimates are provided in the following four categories:

•      improvements in remedy effectiveness
•      reductions in operation and maintenance costs
•      technical improvements
•      gaining site closeout

The recommendations are intended to help the site team identify opportunities for improvements.  In
many cases, further analysis of a recommendation, beyond that provided in this report, may be needed
prior to implementation of the recommendation. Note that the recommendations are based on an
independent evaluation and represent the opinions of the evaluation team.  These recommendations do
not constitute requirements for future action, but rather are provided for the consideration of all site
stakeholders.  This OSE report pertains to conditions that existed at the time of the OSE site visit, and
any site activities that have occurred subsequent to the OSE site visit are not reflected in this OSE report.

The Havertown PCP site is located in Havertown, Haverford Township, Delaware County, in
southeastern Pennsylvania. The  site contamination was first discovered in 1962 when the Pennsylvania
State Department of Health became aware of contaminants in Naylors Run and attributed the  source of
PCP and dioxin contamination to the disposal practices of a nearby wood treating facility. Investigation
and remedial activities have included the removal of existing waste from the site, treatment of effluent
discharging from the existing storm sewer, installation of an oil/water separator, off-site disposal of
generated wastes, installation of a cap over soils impacted by dioxin, and operation of an interim P&T
system, which began operation in 2001. This OSE focused on the operating interim P&T system but also
considers potential enhancements to this system for addressing deeper ground water contamination as
part of the final remedy for Operable Unit 3 (OU3).

The evaluation team observed a conscientious and knowledgeable site team (i.e., EPA and its contractor)
that has effectively managed this interim remedy, provided a number of much needed plant
improvements, and initiated the remedial investigation for OU3.  The  observations and recommendations
contained in this report are not intended to imply a deficiency in the work of either the system designers
or operators but are offered as constructive suggestions in the best interest of the EPA, the public, and the
facility. These recommendations have the obvious benefit of being formulated based upon operational
data unavailable to the original designers.

The recommendations to improve remedy effectiveness include the following:

       The site team should continue with their efforts to investigate and properly seal the abandoned
       sewer line that has allowed contaminated ground water to migrate  downgradient and then surface
       as a seep in a residential area.  The site team should make this effort and the remediation of the
       associated soils and sediments their first priority.

-------
•      Further delineation of the contaminant plume is suggested, especially to the south and at depth.
       Locations and depths for seven new monitoring wells are proposed.

•      Once the plume is delineated, a target capture zone should be determined and the site team
       should conduct a thorough capture zone analysis. A preliminary analysis has been conducted as
       part of this report and is provided in Section 4.2.2.

•      Modifications should be made to O&M practices to reduce system downtime.  Foremost among
       the suggested items is to bypass one or two of the UV/Oxidation units.

Implementation of these recommendations might cost $375,000 to $405,000 in capital costs, but these
costs may be offset by savings associated with cost-reduction recommendations. Recommendations to
reduce cost include the following:

•      Although the site team suggests bypassing one  UV/Oxidation unit, process data suggests that two
       UV/Oxidation units can be bypassed.  As a further option, the site team could consider bypassing
       all three UV/Oxidation units and relying on GAC as the primary treatment technology for
       organic compounds.  Annual savings of approximately $32,000 per year might be possible with
       little or no capital costs if a second UV/Oxidation unit is bypassed. An additional $15,000 per
       year might be saved if the UV/Oxidation system is bypassed altogether.

•      The majority of the annual O&M costs are due to labor. Reductions in both project management
       and sampling labor are likely possible, especially in the near future as contractor modifications
       further simplify the operation of the system.  Potential annual savings of $40,000 per year may be
       feasible within one or two years.

Recommendations for technical improvement include modifying the system to improve treatment
capacity and making minor modifications to the equalization tanks. Recommendations for site closeout
include focusing the remedy on plume containment in the near term rather than aquifer restoration and
considering options for addressing contamination that may be outside of the current capture zone.

A table summarizing the recommendations, including estimated costs and/or savings associated with
those recommendations, is  presented in Section 7.0 of this report.
                                               11

-------
                                      PREFACE
This report was prepared at the request of EPA Region 3 as part of a project to optimize the Region's
pump and treat (P&T) systems that are jointly funded by EPA and the associated State agency.  The
effort was made possible with the help of the Office of Superfund Remediation and Technology
Innovation.  The project contacts are as follows:
           Organization
    Key Contact
        Contact Information
 USEPA Office of Emergency and
 Remedial Response
 (OSRTI)
Kathy Yager
11 Technology Drive (ECA/OEME)
North Chelmsford, MA 01863
phone: 617-918-8362
fax: 617-918-8427
yager.kathleen@epa.gov
 USEPA Region 3
Kathy Davies
USEPA REGION 3
1650 Arch Street
Philadelphia, PA 19103-2029
215-814-3315
davies.katliy@epa.gov
 USEPA Region 3
Norm Kulujian
USEPA REGION 3
1650 Arch Street
Philadelphia, PA 19103-2029
215-814-3130
kulujian.nomi@epa.gov
 GeoTrans, Inc.
 (Contractor to USEPA)
Doug Sutton
GeoTrans, Inc.
2 Paragon Way
Freehold, NJ 07728
(732) 409-0344
Fax: (732) 409-3020
dsutton@geotransinc .com
                                            in

-------
                              TABLE OF CONTENTS
EXECUTIVE SUMMARY 	i

PREFACE  	iii

TABLE OF CONTENTS	iv

1.0 INTRODUCTION	  1
       1.1     PURPOSE	  1
       1.2     TEAM COMPOSITION	  2
       1.3     DOCUMENTS REVIEWED	  2
       1.4     PERSONS CONTACTED                          	  2
       1.5     SITE LOCATION, HISTORY, .AND CHARACTERISTICS  	  3
              1.5.1   LOCATION .AND BRIEF HISTORY	  3
              1.5.2   POTENTIAL SOURCES 	  4
              1.5.3   HYDROGEOLOGIC SETTING	  4
              1.5.4   RECEPTORS  	  5
              1.5.5   DESCRIPTION OF GROUND WATERPLUME	  5

2.0  SYSTEM DESCRIPTION	  7
       2.1     SYSTEM OVERVIEW  	  7
       2.2     EXTRACTION SYSTEM	  7
       2.3     TREATMENT SYSTEM  	  8
       2.4     MONITORING PROGRAM	  9

3.0  SYSTEM OBJECTIVES, PERFORMANCE AND CLOSURE CRITERIA	  10
       3.1     CURRENT SYSTEM OBJECTIVES AND CLOSURE CRITERIA	  10
       3.2     TREATMENT PLANT OPERATION STANDARDS	  11

4.0  FINDINGS AND OBSERVATIONS FROM THE OSE SITE VISIT 	  12
       4.1     FINDINGS 	  12
       4.2     SUBSURFACE PERFORMANCE AND RESPONSE	  12
              4.2.1   WATER LEVELS  	  12
              4.2.2   CAPTURE ZONES 	  12
              4.2.3   CONTAMINANT LEVELS 	  14
       4.3     COMPONENT PERFORMANCE  	  16
              4.3.1   EXTRACTION SYSTEM WELLS, PUMPS, .AND HEADER	  16
              4.3.2   OIL/WATER SEPARATOR AND EQUALIZATION TANK	  16
              4.3.3   METALS REMOVAL SYSTEM	  16
              4.3.4   UV/OX SYSTEM 	  16
              4.3.5   PEROXIDE DESTRUCTION UNIT, CLAY FILTER, AND GAC	  17
              4.3.6   EFFLUENT TANK AND DISCHARGE	  17
              4.3.7   SLUDGE HANDLING TANKS .AND EQUIPMENT	  17
              4.3.8   SYSTEM CONTROLS  	  18
       4.4     COMPONENTS OR PROCESSES THAT ACCOUNT FOR M4JORITY OF ANNUT.AL COSTS	  18
              4.4.1   UTILITIES	  18
              4.4.2   NON-UTILITY CONSUMABLES	  19
              4.4.3   LABOR	  19
              4.4.4   CHEMICAL ANALYSIS	  19
       4.5     RECURRING PROBLEMS OR ISSUES 	  19
       4.6     REGULATORY COMPLIANCE	  20
                                           iv

-------
       4.7    TREATMENT PROCESS EXCURSIONS AND UPSETS, ACCIDENTAL CONTAMINANT/REAGENT RELEASES
               	  20
       4.8    SAFETY RECORD	  20

5.0  EFFECTIVENESS OF THE SYSTEM TO PROTECT HUMAN HEALTH AND THE ENVIRONMENT .  21
       5.1    GROUND WATER  	  21
       5.2    SURFACE WATER	  21
       5.3    AIR	  21
       5.4    SOILS 	  22
       5.5    WETLANDS AND SEDIMENTS	  22

6.0  RECOMMENDATIONS	  23
       6.1    RECOMMENDATIONS TO IMPROVE EFFECTIVENESS	  23
              6.1.1   PROPERLY SEAL ABANDONED 12-lNcn SEWER LINE	  23
              6.1.2   IMPROVE PLUME DELINEATION TO THE SOUTH AND VERTICALLY 	  24
              6.1.3   EVALUATE PLUME CAPTURE ONCE PLUME is DELINEATED 	  25
              6.1.4   TAKE MEASURES TO FURTHER REDUCE SYSTEM DOWNTIME	  26
       6.2    RECOMMENDATIONS TO REDUCE COSTS 	  26
              6.2.1   USE FEWER UV/OXIDATION UNITS 	  26
              6.2.2   EVALUATE AREAS TO REDUCE LABOR COSTS 	  28
       6.3    MODIFICATIONS INTENDED FOR TECHNICAL IMPROVEMENT	  28
              6.3.1   CONTINUE IMPROVING TREATMENT PLANT TO FACILITATE OPERATION AND POTENTIALLY
                     INCREASE CAPACITY  	  28
              6.3.2   MAKE PIPING CHANGES TO BETTER USE THE SECOND EQUALIZATION TANK  	  29
       6.4    CONSIDERATIONS FOR GAINING SITE  CLOSE OUT	  29
              6.4.1   ADAPT P&T SYSTEM TO Focus PRIMARILY ON COST-EFFECTIVE CONTAINMENT WITH
                     DECREASED EMPHASIS ON RESTORATION  	  29
              6.4.2   POTENTIAL OPTIONS FOR IMPROVING CAPTURE	  30
       6.5    SUGGESTED APPROACH TO IMPLEMENTATION 	  31

7.0  SUMMARY	  32
List of Tables

Table 7-1.

List of Figures

Figure 1-1.
Figure 1-2.
Figure 1-3.
Figure 1-4.
Figure 4-1.

Figure 4-2.
Cost summary table
The Havertown PCP Site and the Surrounding Area
Area Immediately Surrounding the Former NWP Facility
Extent of PCP Contamination in the Shallow Zone (Approximately 5 to 20 feet bgs)
Extent of PCP Contamination in the Deep Zone (Approximately 35 to 60 feet bgs)
Potentiometric Surface for Shallow Ground Water Under Pumping Conditions (Approximately 5
to 20 feet bgs)
Potentiometric Surface for Deep Ground Water Under Pumping Conditions (Approximately 40 to
60 feet bgs)

-------
                                 1.0 INTRODUCTION
1.1           PURPOSE

During fiscal years 2000. 2001, and 2002 Remediation System Evaluations (RSEs) were conducted at 24
Fund-lead pump and treat (P&T) sites (i.e., those sites with pump and treat systems funded and managed
by Superfund and the States). Due to the opportunities for system optimization that arose from those
RSEs. EPA Region 3 is expanding efforts to optimize its Fund-lead remedies. Region 3 requested that
GeoTrans conduct RSEs at two of its Fund-lead P&T systems: Havertown PCP and Greenwood
Chemical. Because GeoTrans has a business relationship with Tetra Tech, the contractor at these two
facilities, Optimization Support Evaluations (OSEs) were conducted in place of the RSEs. The OSE
process is identical to the OSE process, but the name change indicates the business relationship between
GeoTrans and Tetra Tech.

The Remediation System Evaluation (RSE) process (and therefore the OSE process)  was developed by
the US Army Corps of Engineers (USAGE) and is documented on the following website:

             http ://www .en vi ronmental .usace .arm v.m i 1/1 ibratv/guide/rsechk/rsechk .html

The evaluation involves a team of expert hydrogeologists and engineers, independent of the site,
conducting a third-party evaluation of site operations. It is a broad evaluation  that considers the goals of
the remedy, site conceptual model, above-ground and subsurface performance, and site exit strategy. The
evaluation includes reviewing site documents, visiting the site for  1 to 1.5 days, and compiling a report
that includes recommendations to improve the system. Recommendations with cost and cost savings
estimates are provided in the following four categories:

•      improvements in remedy effectiveness
       reductions in operation and maintenance costs
•      technical improvements
       gaining site closeout

The recommendations are intended to help the site team identify opportunities for improvements.  In
many cases, further analysis of a recommendation, beyond that provided in this report, might be needed
prior to implementation of the recommendation. Note that the recommendations are  based on an
independent evaluation and represent the opinions of the evaluation team. These recommendations do
not constitute requirements for future action, but rather are provided for the consideration of all site
stakeholders. This OSE report pertains to conditions that existed at the time of the OSE site visit,  and
any site activities that have  occurred subsequent to the OSE site visit are not reflected in this OSE report.

The Havertown PCP site was selected by EPA Region 3 based the potential to improve the effectiveness
of the remedy to protect human health and the environment and to reduce the annual  costs of operating
the remedy. This report provides a brief background on the site and current operations, a summary of the
observations made during a site visit, and recommendations for changes and additional studies. The cost
impacts of the recommendations are also discussed.

-------
1.2
TEAM COMPOSITION
The team conducting the evaluation consisted of the following individuals:

       Rob Greenwald, Hydrogeologist, GeoTrans, Inc.
       Peter Rich, Civil and Environmental Engineer, GeoTrans, Inc.
       Doug Sutton, Water Resources Engineer, GeoTrans, Inc.

The evaluation team was also accompanied by Kathy Davies and Norm Kulujian from EPA Region 3.
1.3
DOCUMENTS REVIEWED
Author
USEPA
USEPA
Calgon Carbon Corp.
Calgon Carbon Corp.
URS
Tetra Tech
Tetra Tech
Tetra Tech
Tetra Tech
Date
8/1989
9/30/1991
4/2001
4/2001
6/13/2001
10/2002-7/2003
8/5/2003
8/5/2003
8/8/2003
Title
Focused Feasibility Study
Operable Unit 2 Record of Decision
Operation and Maintenance Manual, Volume I:
RAY OX Advanced Oxidation System
Operating Manual: Mobil Model 6 Granular
Carbon Adsorption System
Preliminary Draft Operations and Maintenance
Manual: Havertown PCP Superfund Site
Project Meeting Agendas
NAPL Recovery Data
Process Monitoring Data
Supplementary Data and Figures
1.4
PERSONS CONTACTED
The following individuals associated with the site were present for the visit:

Jill Lowe, Remedial Project Manager, EPA Region 3
Mindi Snoparsky, Hydrogeologist, EPA Region 3

Harish Mital, Project Manager and Engineer, Tetra Tech
Andy Westerbaan, Hydrogeologist, Tetra Tech
J.B. Moore, Project Engineer, Tetra Tech
Dale Gant, Plant Operator, Tetra Tech

-------
1.5           SITE LOCATION, HISTORY, AND CHARACTERISTICS

1.5.1          LOCATION AND BRIEF HISTORY

The Havertown PCP site is located in Havertown, Haverford Township, Delaware County, in
southeastern Pennsylvania. The site is located approximately 10 miles west of Philadelphia and is
surrounded by a mixture of commercial establishments, industrial companies, parks, schools, and private
homes. The location of the site and the surrounding area are depicted in Figure 1-1. The entire
Havertown PCP site is approximately 12 to 15 acres, and is comprised of a former wood-treatment
facility operated by National Wood Preservers (NWP), the Philadelphia Chewing Gum Company (PCG)
manufacturing plant adjacent to the wood-treatment facility, Naylors Run (a creek that drains the area),
and neighboring residential and commercial properties. A more detailed plan of the site is shown in
Figure 1-2.

The NWP facility is the primary source of the contamination for the site. The NWP facility was first
developed as a railroad storage yard, and in 1947 it began operation as a wood-preserving facility. The
site contamination was first discovered in 1962 when the Pennsylvania State Department of Health
became aware of contaminants in Naylors Run and linked the source of contamination to the NWP waste
disposal practices. The  following four media have been documented as being affected by contaminants
originating from the site:

       on-site soils
       on-site and downgradient ground water
       surface water in storm sewers and off-site in Naylors Run
       air on-site and in the vicinity of the catch basin on Naylors  Run

Investigation and remedial activities have included the removal of existing waste from the site, capping
of impacted soil and debris on-site, treatment of effluent discharging from the existing storm sewer,
installation of an  oil/water separator and off-site disposal of generated wastes. Other investigation and
remedial activities conducted at this site include the following:

1972     -    The Pennsylvania Department of Environmental Resources (PADER) identified
              contaminated ground water discharging from a storm sewer into Naylors Run

1976     -    The EPA initiated activities and commenced containment operations under Section 311
              of Clean Water Act in response to request from  PADER

1982     -    The site was placed on the National Priorities List

1982-84  -    PADER and EPA conducted subsequent inspections and found many  deficiencies with
              the containment operations, and EPA issued a unilateral Administrative Order against
              NWP which required NWP to perform various abatement activities

1987-89  -    PADER performed the Remedial Investigation/Feasibility Study  for Operable Unit  One
              (OU1), and the EPA issued an interim Record of Decision (ROD) for OU1 which
              addressed the cleanup of wastes currently staged on the site from previous investigative
              actions and included interim remedial measure of designing and installing an oil/water
              separator

1988     -    A catch basin was installed in Naylors Run to trap the discharge from the storm pipe by
              EPA's Emergency Response Team to prevent the release of PCP-contaminated oil into
              Naylors Run

-------
1991     -     The EPA initiated the Remedial Investigation/Feasibility Study for Operable Unit Two
               (OU2), and issued a ROD for OU2 that addressed the treatment of the shallow ground
               water aquifer

1994     -     A cap completed to cover soils impacted by dioxin

2001     -     A P&T system was completed and began operation under Operable Unit 2 (OU2) as an
               interim remedy for shallow ground water


The principal threat at the site remains the ground water contamination by PCP and other contaminants
of concern that occurred as a result of wood-treatment operations atNWP, including  dioxins and
dibenzofurans, fuel oil and mineral spirits components, heavy metals, certain volatile organic
compounds, and phenols. This OSE report pertains to the ground water contamination, the operating
interim P&T system, potential alternative approaches to addressing the ground water contamination, and
site conditions that directly affect the ground water remediation.

1.5.2           POTENTIAL SOURCES

The use of an injection or disposal well to collect the spent wood-treating solutions containing PCP and
oil was allegedly the major source of contamination to the environment from 1947 until  1963 when
disposal practices at NWP changed. It is estimated that up to one million gallons of spent solution may
have been disposed of by this method. The uncontrolled disposal methods and typically poor
housekeeping practices prior to 1963  resulted in significant contamination of the ground water
surrounding the site.  The presence of the light non-aqueous phase liquid (LNAPL) in wells R-2 and
HAV-02 continue to contribute to the dissolved ground water contamination. An estimated volume of
6,000 gallons of NAPL (approximately 2 inches thick) is present over the ground water in this area.

During the ongoing OU3 investigation (OU3 pertains to the remediation of the sediment contamination in
Naylors Run, the deep ground water aquifer which is fractured bedrock, and surface water and sediment
contamination due to runoff from on-site soils) an abandoned sanitary sewer line was found which may
act as a preferential pathway for contaminant transport to the Residential Open Space area southeast of
Achille Road on Naylors Run.

1.5.3           HYDROGEOLOGIC SETTING

The site is located in the Piedmont Upland section of the Piedmont Physiographic Province. Bedrock in
the site vicinity consists of metamorphic rocks of Wissahickon Formation. The site is in an area that is
relatively flat compared to the  surrounding countryside. Much of the  area's original topography  has been
altered by cut and fill activities on both the NWP plant site and the PCG property.  The site lies
approximately 300 ft above mean sea level (MSL). The depth to ground water beneath the site ranges
from approximately 23 ft below ground surface in the Young's Produce Store area to approximately 0.5
ft below ground surface in the Rittenhouse Circle area. Ground water in the vicinity of the site flows in
an easterly direction, with some unknown portion discharging to Naylors Run. For the most part, surface
runoff across the NWP site enters artificial drainage channels before  discharging into Naylors Run.

According to the 1991  OU2  ROD, ground water at the site flows in an easterly direction and occurs in
two major zones. The upper zone consists of surficial soils and weathered schist saprolite.  In general,
this upper zone  extends to approximately 30 feet below ground surface. The lower zone consists of
highly fractured and jointed  schist bedrock, with water movement occurring along interconnected
fractures. The bedrock aquifer receives some of its recharge from the downward flow through the
overburden aquifer, but upward flow  from the bedrock to the overburden exists further downgradient,

-------
presumably as ground water discharges to Naylors Run. Some portion of the ground water in the deep
aquifer likely travels under Naylors Run via fractures and discharges further downgradient to the
southeast.

According to the ROD, the ground water velocity in the shallow aquifer is approximately 85 ft per year,
presumably based on aquifer testing and measurement of the hydraulic gradient. At the time of the ROD,
however, the extent of contaminant migration suggested that other factors, such as adsorption, were
limiting the rate of contaminant transport. Ground water flow velocity in the deep aquifer, within the
underlying fractured bedrock, is estimated to be 25 ft per year according to the ROD.

The presence of underground sewers that intercept the water table has altered ground water flow patterns
and contaminant transport at the site. Prior to site remedial activities, contaminated ground water
infiltrated into a 30-inch sewer line near the PCG property.  Although this sewer line reduced the amount
of contamination that could migrate downgradient, this contaminated water discharged directly to
Naylors Run. As part of OU2, EPA lined the 30-inch sewer line to reduce its ability to collect and
discharge contaminated water. A collector drain, which is a component of the interim ground water
remedy, was installed in this general area to intercept and extract contaminated ground water in the
shallow zone (i.e., overburden).

In 1999, the  site team identified a contaminated seep adjacent to Naylors Run  (location indicated on
Figure 1-1).  By the Summer of 2003, the  site team found an abandoned 12-inch sewer line that has likely
been facilitating the transport of contaminated ground water downgradient and causing the seep. PCP
concentrations of over 500 ug/L have been observed at this downgradient location even though
upgradient monitoring points (such as the CW-12 cluster) show lower or undetectable concentrations.
During the OSE visit, the site team showed the OSE team the seep area where impacted water was
surfacing and indicated that addressing this sewer line, seep, and resulting contamination is a top priority.

1.5.4          RECEPTORS

The area potentially affected by contaminants released from the Havertown PCP site is almost entirely
developed. The primary contamination source (NWP) is located in midst of several commercial
establishments and surrounded by a mix of private homes, schools, stores, parks, and industrial facilities.
Consequently, humans potentially make up the most important receptor group. Additional environmental
receptors may include vegetation, aquatic biota, wildlife and domestic animals, and agricultural or garden
products.

Because the  contaminated soil has either been removed or covered with a cap, the primary routes of
exposure to site-related contaminants would include extraction and use of contaminated ground water,
direct contact with contaminated ground water that has seeped to the surface, or construction activities
beneath the cap. With the exception of the above-mentioned seep caused by the 12-inch sewer line,
recent surface water sampling indicates low (i.e., at or near MCLs) contaminant concentrations in
Naylors Run, which is  a substantial improvement compared to the 1,200 ug/L that had been detected in
Naylors Run near the PCG property during the initial investigations.

1.5.5          DESCRIPTION OF GROUND WATER PLUME

Figure 1 -3 shows the extent of PCP contamination near the NWP and PCG properties in the shallow
aquifer (overburden), and Figure 1-4 shows the extent of PCP contamination in the same area for a
deeper aquifer interval (fractured bedrock).  The highest detected levels of PCP at the time of the OSE
are 13,000 ug/L in R-2, 30,000 ug/L in HAV-02, and 8,700 ug/L in HAV-04 (March 2003 sampling

-------
event). Wells R-2 and HAV-02 are located just downgradient of the site along Eagle Road, and well
HAV-04 is located approximately 450 feet downgradient of the site. PCP contamination at further
downgradient locations is relatively low compared to upgradient. The CW-9 and CW-13 clusters (see
Figure 1-1) are the only clusters downgradient of the collector drain with detectable PCP concentrations
since sampling began at downgradient locations in October 2002.

Dioxin is also present in the ground water. The last comprehensive ground water sampling round for
dioxin was conducted in 2000, and the highest concentrations were found in CW-2D, HAV-02, and NW-
1-81, which are located either on the former NWP property or immediately downgradient of it.  In
general, the highest dioxin concentrations are found in the wells with the highest PCP concentrations.
Dioxin concentrations in wells downgradient of the collector drain (see Figure 1-2 for well locations) are
below the  MCL of 0.03 ppt (0.00003 ppb).

-------
                            2.0   SYSTEM DESCRIPTION
2.1
SYSTEM OVERVIEW
The ground water extraction system consists of 4 recovery wells located along Eagle Road and a 180-foot
long collector drain installed to the top of bedrock (16 feet bgs) downgradient of the PCG facility . The
collector drain is located adjacent to the existing storm sewer line to collect contaminated shallow ground
water for treatment at the treatment plant. The purpose of the collector drain is to effectively capture the
plume of contaminated water in the shallow aquifer as it flows to the east. The recovery wells collect
impacted ground water and LNAPL near the source area. The system was constructed by one contractor
in 2001, operated by another contractor through July 2002, and has since been operated by a third
contractor.

The treatment system consists of an oil/water separator (OWS), chemical precipitation system, an
advanced oxidation process system, and granular activated carbon (GAC) system, sequentially. The
treated water is discharged into Naylors Run.

The following table summarizes the contaminant concentrations in the plant influent for June 2003. The
effluent standards are also provided.
Parameter
Cobalt
Iron
Manganese
Benzene
Trichloroethylene
Pentachlorophenol
Phenanthrene
Dioxins/Furans (ppq***)
June 2003 Influent Concentration
(ug/L)
135
5,320
10,300
6.9
9.9
2600
25*
315.5 **
NPDES Monthly
Average Effluent
Standard
(ug/L)
53
300
50
1
5
1
3
<4.4
       * Concentration below the detection limit. The data comes from previous sampling event on 5/29/2003
       ** No data during June 2003 sampling event. The data comes from previous sampling event on 5/29/03
       *** ppq - parts per quadrillion or picograms per liter
2.2
EXTRACTION SYSTEM
The ground water extraction system includes 4 recovery wells labeled RW-1 through RW-4 and the
collector drain. With the exception of RW-3, which is located on the PCG property directly downgradient
of R-2, the recovery wells are on or adjacent to NWP property in the vicinity of the hot spot at well R-2.

-------
They range from 26 to 28 feet deep (i.e, to the interface of the overburden and fractured bedrock).  These
wells have QED AP-4 pneumatic submersible pumps.  Only 1 of the 4 wells, RW-1, is currently pumping
over 2 gpm, and two of the wells (RW-3 and RW-4) are not pumping at all. The wells are in need of
redevelopment, which was planned for late August 2003.

Three extraction wells (EW-1, EW-2, and EW-3) were drilled as part of the OU2 effort, but have not
been used for ground water recovery purposes.  R-2, a 4-inch monitoring well located on the former
NWP property, is manually bailed.  Eight events have taken place since October 2002, recovering
approximately 19 gallons of product.
2.3            TREATMENT SYSTEM

The primary components of the treatment system are listed below.

Free product separation and storage
       oil/water separator with the capacity of 100 gpm that gravity drains water to the equalization
       tanks
       5,900 gallon free product tank with level transmitter to store product draining from the oil/water
       separator and bailed from R-2
       two 200 cfm capacity GAC units to treat vapors vented from the oil/water separator and free
       product tank

Flow equalization, metals removal and solids handling
       two 2,800 gallon equalization tanks
       50 gpm equalization tank discharge pump with standby unit
       three 800 gallon oxidation and mixing tanks with chemical and polymer addition
       lamella plate clarifier unit with flash mix and flocculation chambers with a 55 gpm capacity
       double diaphragm sludge pump at the oil/water separator and clarifier
       upflow sand filter with a 50 gpm capacity
       4,500 gallon sludge holding tank to store the sludge from the oil/water separator, the clarifier,
       and sand filter
       filter press with 20 cubic foot capacity

UV/Oxidation
       2,000 gallon metals removal effluent  surge tank and 45 gpm RayOx feed pumps (two including
       one standby)
•      RayOx system including three 30 KW UV reactors in series
       peroxide destruction unit with 2,000 pounds of GAC  and 2,000-pound clay filter (currently off-
       line)
       two parallel cartridge filters
GAC
       two 4,000-pound GAC units arranged in series
•      two 3,000 gallon effluent tanks

In addition, the system includes a 450 gallon sump with a pump for recycling filter press filtrate, decant
water from the sludge thickener and sand filter backwash water; an air compressor (to operate the
recovery well extraction pumps); and controls with remote access and data storage capabilities.

-------
The treatment system was designed to treat 40 gpm. The flow from the recovery wells and the collection
drain is directed to the oil/water separator and the above-mentioned treatment components prior to being
discharged to Naylors Run.
2.4           MONITORING PROGRAM

Process monitoring consists of monthly influent and semi-monthly effluent sampling for VOCs, SVOCs,
metals, and dioxins/furans. Eight process samples are collected and analyzed quarterly to monitor the
performance of individual treatment components, with analysis of each sample dependent on its location
relative to individual treatment components.

Ground water monitoring includes sampling 10 wells quarterly,  10 wells semi-annually, and about 55 to
60 wells annually (planned). The last comprehensive ground water sampling event was conducted in
October 2002 when approximately 33 wells were sampled. At least 7 of the wells that were not sampled
were either dry or had product. All ground water samples (approximately 100 per year) are analyzed for
VOCs, SVOCs, and metals. About 50 of those 100 samples are analyzed for dioxins/furans.

-------
      3.0   SYSTEM OBJECTIVES, PERFORMANCE AND CLOSURE
                                       CRITERIA
3.1           CURRENT SYSTEM OBJECTIVES AND CLOSURE CRITERIA

The 1989 ROD for OU1 identified three operable units (OUs) and associated remedies:

OU1 -  the removal of existing hazardous wastes from the site and the installation of an oil/water
       separator for removing some contaminants from Naylors Run

OU2 -  the remediation of the shallow ground water aquifer (overburden), considered as an interim
       action for ground water

OUS -  the remediation of the sediment contamination in Naylors Run. the deep ground water aquifer
       (fractured bedrock), and surface water and sediment contamination due to runoff from on-site
       soils

Additionally, a cap was installed in 1994 (between OU1 and OU2) as a removal action.

This optimization evaluation primarily pertains to the OU2 remedy but also considers potential options
for a final ground water remedy. As stated in a 1991 ROD, OU2 includes an interim remedy for shallow
ground water. The objective of this interim remedy is to collect and treat the shallow ground water that
flows into Naylors Run and initiate the remediation of the shallow ground water. The primary purpose is
to protect children that might play in Naylors Run. This is not a final remedy for ground water because it
only addresses shallow ground water and not both shallow and deep  ground water.  The information
collected during this interim remedy will help in the planning of the  OUS remedy, which would include
remediation of the contaminated sediment and a final remedy for ground water.

The selected interim OU2 remedy includes the following major features:

       Installation office product recovery wells on the NWP property to recover product from the
       shallow aquifer

•      Rehabilitation of the existing storm sewer line to reduce infiltration of contaminated ground
       water from the shallow aquifer to the stonii sewer

       Installation of a ground water collection drain adjacent to the existing storm sewer line and to the
       top of bedrock to extract contaminated ground water in the overburden

•      Installation of a ground water treatment plant at NWP to perform chemical precipitation, either
       powdered activated carbon treatment or an advanced oxidation treatment, and finally granulated
       activated carbon (GAC) polishing.


Concurrent with operating the OU2 remedy, the site team is conducting the OUS Remedial Investigation.
The objectives are to evaluate sources, nature, extent, migration pathways, and receptors of site-related
contamination in deep ground water. These efforts include the addition of 13 monitoring wells (vertical
well pairs CW-9 through CW-14 and single well CW-15), sampling  of site-wide wells, sampling of
surface water, pumping tests, ground water flow  modeling, and an evaluation of the recovery system.
                                             10

-------
3.2
TREATMENT PLANT OPERATION STANDARDS
The design influent concentration and effluent concentration standards for the primary contaminants of
concern are summarized in the following table.
Contaminants of
Concern
PCP
Phenanthrene
Benzene
Trichloroethylene
TCDD (dioxins/furans)
TSS
Cobalt
Iron
Manganese
Oil & Grease
Design Influent
Concentration
llmg/L



lug/L
lOmg/L

270 mg/L
13.8 mg/L
3,500 mg/L
NPDES Monthly Average
Effluent Standard
1 ug/L
3ug/L
lug/L
5 ug/L
< 4.4 ppq
No standard
53 ug/1
300 ug/L
50 ug/L
15 mg/L
                                       11

-------
    4.0  FINDINGS AND OBSERVATIONS FROM THE OSE SITE VISIT
4.1           FINDINGS

The evaluation team observed a conscientious and knowledgeable site team (i.e., EPA and its contractor)
that has effectively managed this interim remedy, provided a number of much needed plant
improvements, and initiated the remedial investigation for OU3. The observations provided below are
not intended to imply a deficiency in the work of the system designers, system operators, or site
managers but are offered as constructive suggestions in the best interest of the EPA and the public.
These observations obviously have the benefit of being formulated based upon operational data
unavailable to the original designers. Furthermore, it is likely that site conditions and general knowledge
of ground water remediation have changed over time.
4.2           SUBSURFACE PERFORMANCE AND RESPONSE

4.2.1          WATER LEVELS

Water levels collected in both the shallow zone (overburden) and deep zone (bedrock) in March 2003
have been used by the site team to generate potentiometric surface maps. These maps are presented in
Figures 4-1 and 4-2. Approximately 29 measurement points are used to generate the shallow
potentiometric surface map, and approximately 14 measurement points are used to generate the deep
potentiometric surface map.  Both figures show ground water flow to the southeast, and both figures
show the influence of the collector drain. As expected, the influence of the collector drain in the shallow
zone is more predominant than the influence in the deeper zone. This is partially due to the use of water
level measurement points within the drain when generating the shallow potentiometric surface.
Nevertheless, the influence of the drain on the deeper water level measurements suggests that,  under
pumping conditions, some water in the deeper aquifer is entrained by the drain. These two figures, when
compared with each other, can be used to interpret vertical ground water flow, but no easily discernible
trend is recognized.

These water levels only pertain to the conditions during the Spring of 2003, and more specifically to
March 2003. Water levels conducted at different times may suggest seasonal variation in both horizontal
and vertical ground water flow.

4.2.2          CAPTURE ZONES

As part of this report, the OSE team has used the March 2003 potentiometric surface maps generated by
the site team to interpret the horizontal capture in both the shallow and deep zones.  The interpreted areas
of capture are depicted in Figures 4-1 and 4-2, with the shallow capture zone more extensive than the
deeper capture zone. Therefore, ground water that flows up from within the deeper capture zone should
be within the shallower capture zone.  These preliminary analyses consider only one round of water
levels and do not rigorously consider vertical flow. Because water levels may change seasonally
affecting both horizontal and vertical flow, a more thorough capture zone analysis is merited.

No particular target capture zone appears to have been documented by the site team. This is likely
because OU2 is an interim remedy and because the collector drain could not be extended as far to the


                                             12

-------
south as originally planned due to the residences.  Nevertheless, the surface water contamination in
Naylors Run has decreased, and the interpreted shallow capture zone appears to provide capture for the
most contaminated portions of the site, including the contamination at CW-4 and CW-5. This contrasts
with a more thorough capture zone evaluation conducted by the site team with the water levels collected
during December 2002 (not provided in this report). The deeper capture zone interpreted from the March
2003 data is also fairly extensive but does not appear to include the contamination at CW-4 and CW-5.

A water budget analysis can also be conducted to provide a simplistic evaluation of capture.  The
following parameter values  are relevant.

•      According to the 1991 ROD, the ground water velocity in the shallow aquifer is approximately
       85 feet per year (0.23 feet per day).  Assuming this ground water velocity was calculated using a
       porosity of 0.30, this translates to a Darcy velocity of approximately 25.5 feet per year (0.07 feet
       per day).

•      Conservatively, the saturated thickness of the overburden (and perhaps the upper portion of the
       fractured bedrock) is 35 feet.

•      Approximately 20 gpm (3,860 ft3 per day) is extracted from the trench.

Assuming limited infiltration from precipitation or from the underlying formation, the amount of water
extracted by the drain is equal to the amount of water flowing through a given cross-section of the
aquifer. This equality can be expressed as follows (Q=VdWb).  where Vd is the Darcy velocity, Wis the
width of the cross-section, and b is the saturated thickness. This equation can be rearranged to solve for
the width.

                                     Q__  3,860^
                                     Vdb~ 0.07 fax 35ft ~  '    J

This result suggests that the width of capture is approximately  1,575 feet; however, this result is based on
the simplifying assumption that there is no infiltration from precipitation or from the underlying
formation. Much of the overlying ground is paved, which means that there is likely little contribution
from precipitation. However, the potentiometric surface for the deeper zone indicates influence from the
collector drain. Therefore, the capture zone width is likely smaller than the 1,575 feet because the
effective capture zone depth is likely greater than the 35 feet that was assumed in the water budget
calculation. In general, the water budget analysis supports the interpretation from the potentiometric
surface maps that capture is fairly extensive across the site. Neither of the above evaluations, however,
confirm complete capture across the site, especially  in areas where contamination has not been fully
delineated (i.e., vertically and to the south).

Water quality sampling from downgradient wells can also be used to evaluate capture.  The October 2002
sampling event included sampling of clusters CW-9 through CW-14 and sampling of CW-15. With the
exception of CW-9S, all of the shallow samples had undetectable concentrations of PCP.  All of the
shallow samples had  concentrations of dioxins under the MCL  of 0.03 ppt.  The elevated PCP
concentration at CW-9S (70 ug/L) suggests that contamination  either reached this location prior to
operation of the interim OU2 ground water remedy,  that capture is incomplete and PCP contaminated
ground water continues to migrate from the source area to this location, or that CW-9S  is located inside
the capture zone.  It is reasonable to assume that this contamination at CW-9S was present prior to
pumping, or, based on Figure 4-1, it is reasonable to conclude that CW-9S is within the capture zone. To
evaluate capture in the future, the trend in CW-9S can be analyzed, but the results may be inconclusive.

                                               13

-------
If the trend shows decreasing concentrations toward background, this will indicate that CW-9S is outside
of the capture zone and that capture is successful.  If concentrations remain the same or increase, this
could mean that CW-9S is either within the capture zone or that capture is not successful. Therefore.
evaluation of capture should not depend heavily on sampling results from CW-9S.

With the exception of CW-9D and CW-13D, the downgradient wells in the October 2002 ground water
sampling event had undetectable concentrations of PCP and dioxin levels below the MCL. As with the
shallow zone, this contamination may have been present before operation of the OU2 system began.  If
capture is sufficient, the concentrations should decrease to background (i.e., zero) overtime. If the
concentrations consistently remain elevated or increase, then capture is likely insufficient.

A primary concern regarding capture is the presence of an abandoned 12-inch sewer line that is likely
acting as a conduit for contaminated ground water. This sewer line apparently ends near Naylors Run in
the location of "impacted seeps"' indicated on Figure 1-1.

In general, the interim remedy has functioned as designed by substantially reducing contaminant
transport into Naylors Run. Capture in the shallow zone may or may not be complete, but a number of
lines of evidence suggest that the capture zone is fairly extensive and extends into the deeper zone.
Addressing the abandoned sewer line, first discovered in Summer 2003, presents the most severe issue
with respect to contaminant migration and further impacts to Naylors Run.

4.2.3          CONTAMINANT LEVELS

Ground water sampling in October 2002 provides an indication of the extent of ground water
contamination.  The most impacted areas are beneath the former NWP property and the PCG property.
Concentrations downgradient of these properties are relatively low and even undetectable in most
locations.  Ground water sampling has not been conducted long enough to evaluate a trend toward
cleanup. However, it is reasonable to conclude that concentrations upgradient of the collector drain have
not decreased substantially. NAPL remains a continuing source in this area, minimal background flow is
present to flush the contaminants toward the collector drain, and the recovery wells have been fairly-
unsuccessful at recovering NAPL.

The ground water sampling is also relatively incomplete in terms of delineating the plume, particularly to
the south and in the vertical direction. The wells in the CW-4 and CW-5 clusters are the southern most
wells near Eagle Road, and as shown in Figures 1-3 and 1-4, the PCP concentrations at these wells
exceed 1,000 ug/L. With no additional wells to the south, the PCP plume is not delineated. This lack of
delineation affects the preliminary capture zone analysis conducted above because the degree of capture
cannot be determined without full delineation.  As depicted in Figure 1-4, a number of deep wells with
screened intervals down to approximately 50 feet below ground surface have concentrations exceeding
1,000 ug/L. Without deeper wells, the PCP plume cannot be considered delineated vertically. In EW-1
through EW-3 (extraction wells located upgradient of the collector drain that have never been used for
pumping), the concentrations are also above 1,000 ug/L. These wells are screened from approximately
40 to 80 feet bgs, whereas the collector drain is completed to approximately 16 feet bgs. With this
relatively long screened interval, the vertical extent of contamination cannot be determined. The
contamination may only be present near the tops of these relatively long screened intervals, but it may
also be present at deeper levels. In addition, these wells may be acting as conduits, allowing
contamination at approximately 40 feet to migrate to depths near 80 feet. The upward gradient in this
area due to the operation of the collector drain makes this downward migration unlikely, but this
possibility should not be eliminated without deeper sampling.
                                               14

-------
The concentrations entering the treatment plant are below the design values.  The influent concentrations
and the design concentrations are compared in the following table.
Parameter
PCP
Dioxins/Furans
Iron
Manganese
Oil and Grease
Total VOCs
Design Influent Concentration
(ug/L)
11,000
1
270,000
13,800
3,500,000
No design value
Actual Influent
Concentration* (ug/L)
3,900
0.0015
8,400
11,000
15,000
<100
        * Average influent concentration between September 2002 and June 2003 rounded to t\vo significant digits

The mass removal rate for PCP. assuming the above concentration and an extraction rate of 20 gpm, has
been approximately 1 pound per day as shown in the following equation.
                   20 gal   3,900ug  3.785L   1440mm.   2.2 Ibs
                   	:—x	x	—x
                             0.94 Ibs
                    mm.
gal.
day
10 ug     day
Mass removal of other VOCs and SVOCs (including benzene, trichloroethylene, and naphthalene) is also
occurring, but at a much reduced level compared to the mass removal of PCP. The following table
presents those constituents in the influent that are above the discharge standards and require treatment.
Parameter
Benzene
Trichloroethylene
Naphthalene
PCP
Phenanthrene
Oil and Grease
Aluminum
Cobalt
Iron
Lead
Manganese
Maximum Influent Concentration
(ug/L)
12
15
1,800
9,500
400
61,200
2,470
227
43,500
8.6
12,300
NPDES Monthly Average
Effluent Standard (ug/L)
1
5
30
1
3
15,000
360
53
300
5
50
        ' Influent data from September 2002 through June 2003
Sampling data indicate that effluent concentrations of all the primary contaminants of concern are below
the effluent standards with the exception of manganese. The site team determined that the manganese
was leaching from the clay filter.  The clay has since been taken offline, and exceedances of manganese
have not occurred since.
                                               15

-------
4.3            COMPONENT PERFORMANCE

4.3.1           EXTRACTION SYSTEM WELLS, PUMPS, AND HEADER

The extraction system consists of the collector drain and the four recovery wells.  The collector drain is
constructed like a french drain in a trench that is approximately 2 feet wide. 180 feet long, and
approximately 15 to 20 feet deep (completed to the top of bedrock). Water from the drain enters a four
foot sump where a Grundfos electric submersible pump directs water to the treatment plant in a 2-inch
pipe. Potential flow is limited by a 1-inch connection located in the piping near the drain. Four
piezometers are completed within the trench to provide  an indication of drawdown.  The high and low
level settings for transducers in the trench are not known, and there is not sufficient pumping capacity to
reach the low level. The drain sump is  reportedly full of solids and requires cleaning.

The recovery wells are completed to the top of bedrock, which is about 30 feet bgs.  They operate well
below expected recovery rates, with only one well pumping over 2 gpm. None  of the wells produce
much product. The majority of recovered product is collected  manually from R-2, which is located
adjacent to RW-2. All of the wells are in need of rehabilitation.

Three 6-inch wells (EW-1  through EW-3) were drilled,  but were not converted  to extraction wells and
have not operated. These wells are screened from 40 to 80 feet bgs just upgradient of the trench.

The extraction system piping is equipped with a leak detection system, but this  system frequently sets off
alarms due to precipitation inflow (not associated with leaks).  These alarms shut down the extraction,
causing downtime.  The site team has therefore disconnected the leak detection system, allowing the
system to avoid unnecessary downtime during rain events.

4.3.2           OIL/WATER SEPARATOR AND EQUALIZATION TANK

The oil/water separator receives an influent flow of about 20 to 25 gpm typically. Minimal LNAPL is
recovered by the separator system. The free product tank is extremely oversized for this application; the
site team has added a fill line and level transmitter to make the tank easier to use.  The two 2,800-gallon
equalization tanks receive  water from the oil/water separator.  The site contractor has added a level
transmitter within the first tank and a site tube for local  level reading. The equalization tank effluent
pump basket strainers and ball check valves require daily cleaning to keep the plant operational.

4.3.3           METALS REMOVAL SYSTEM

The three 800-gallon tanks allow for chemical addition and mixing.  Transfer from one tank to the next is
gravity fed, and the first tank is the rate-limiting step for the entire treatment plant.  Although the plant is
reportedly designed for 40 gpm, the first tank begins to  overflow (or at least splash over) at just under 40
gpm. The other components of the metals removal system, including the other tanks, chemical addition,
lamella clarifier, and sand  filter operate as expected. Nevertheless, they require frequent cleaning. The
May 2003 process sampling indicates that the effluent from the clarifier meets the metals discharge
standards.

4.3.4           UV/OX SYSTEM

Water from the sand filter discharges to a surge tank where a 50% hydrogen peroxide solution is added to
the process  water for a hydrogen peroxide concentration of 200 ppm. The water from this surge tank is
then pumped through the UV/OX system, which consists of three 30 KW reactors arranged in series. The

                                              16

-------
May 2003 process sampling indicates that the effluent from the first UV reactor meets all of the organic
discharge standards with the exception of PCP.  The PCP concentration at this location in May 2003 was
2.3 ug/L compared to the discharge standard of 1 ug/L, which could easily be removed by remaining UV
reactors or simply GAC units alone.

Maintenance of the UV/OX system involves replacement of the seals and bulbs and periodic cleaning of
the surge tank and reactors. The site team plans to add bag filters between the sand filter and the surge
tank to remove solids that pass through the sand filter. This should reduce the amount of solids entering
the surge tank and the UV/OX system.

The UV/OX system has been the primary reason for the above-average downtime.  Between April and
July 2003, plant uptime was only 64%. Main problems include lamp failures, a blower motor failure, and
an insufficient inventory of replacement parts. The blower motor failure alone resulted in a four-day
shutdown because the part was not on hand.

4.3.5          PEROXIDE DESTRUCTION UNIT, CLAY FILTER, AND GAC

The peroxide destruction unit (PDU) operates as intended, reducing the hydrogen peroxide concentration
to 10 ppm or less. The site team has replaced the 2,000 pounds of carbon in this unit once and has added
the capability to backwash the PDU. The clay filter has been taken offline due to the leaching of
manganese that had built up overtime and was causing periodic exceedances of the manganese discharge
standard. The clay filter was not needed  or helpful in reaching organic treatment standards. Cartridge
filters are used to further reduce solids prior to the GAC.

The two 4,000-pound GAC units have been replaced once since the plant began operation in 2001.  The
replacement was not due to organic contaminant loading or to pressure build up. It was due to the
potential leaching of manganese that had built up over time and was potentially contributing to
exceedances of the manganese discharge criteria.

Frequent backwashing  of the GAC and PDU have contributed to the system downtime. This is primarily
because the current design of the treatment plant does not allow for storage of the waste water generated
from the backwashing.  As  a result, extraction needs to be temporarily stopped to allow continued
treatment to provide capacity in the equalization tanks.

4.3.6          EFFLUENT TANK AND DISCHARGE

Prior to discharge via pumping to Naylors Run, the process water is emptied into two 3,000-gallon
effluent tanks that are located outside of the plant building. As with other treatment components, the
effluent tanks and pumps require frequent cleaning due to biological build up.

4.3.7          SLUDGE HANDLING TANKS AND EQUIPMENT

Sludge from the system clarifier, oil/water separator, and the sand filter is thickened in a  4,500-gallon
sludge holding tank prior to being dewatered in a filter press.  The filter press is operated about once per
week.  Approximately  10 cubic yards of sludge is disposed of every 8 to 12 weeks. The sludge is
hazardous because it is listed waste (F032) and contains dioxins. This sludge and the recovered product
(in liquid form) is shipped and incinerated.
                                              17

-------
4.3.8
SYSTEM CONTROLS
The site team has added a number of flow meters, high and low level controls, and sensors to facilitate
plant operation.  It has also added a PC, software for trending analyses, and a DSL with PC Anywhere
software for remote access and viewing. Original documentation on the control system is limited.
4.4
COMPONENTS OR PROCESSES THAT ACCOUNT FOR MAJORITY OF
ANNUAL COSTS
Annual O&M costs for year two of the current contract (2003-2004) are approximately 591,000 per year,
which marks a decrease of $68,000 compared to the O&M costs for year one of the current contract
(2002-2003). The following table presents an estimated breakdown of Year-2 annual costs as provided
by the site contractor. A cost of $50,000 was incurred in Year 1 and is expected in Year 2 for major
equipment changes and plant improvements, but this $50,000 cost is not included in the table because
such repairs/improvement should not be indicative of future O&M. All presented costs are approximate.
                              Item Description
 Labor: Project management and reporting, technical support, and design of plant
 improvements
 Labor: Plant operator (one full-time operator, one part-time engineer to upgrade the
 remedy)
 Labor: Process and ground water sampling and data analysis
 Utilities: Electricity (assumes two operating UV/OX units)
 Utilities: Water, phone, garbage, and cap maintenance
 Non-utility consumables: chemicals
 Non-utility consumables: UV lamps/accessories (assumes two operating UV/OX units)
 Non-utility consumables: GAC
 Chemical Analysis
 Routine maintenance items
 Waste disposal
                                                                Estimated Cost
                                                                  $75,000 per year

                                                                 $180,000 per year

                                                                  $75,000 per year
                                                                  $55,000 per year1
                                                                  $15,000 peryear
                                                                  $70,000 per year
                                                                  $16,000 per year
                                                                  $20,000 per year2
                                                                            N/A3
                                                                  $30,000 per year4
                                                                  $55,000 per year4
                                                       Total Estimated Cost
                                                                        $591,000
1 Site contractor estimated $75,000 using three UVOX units, $55,000 is a rough estimate for two UVOX units (some of the
electricity costs are due to pumps/motors and will not decrease with bypassing a UV/OX unit).
2 Site contractor estimated $40,000 in Year 1 for one replacement of two units and no replacements in Year 2. The OSE team
estimates $20.000 per year for one replacement of one unit.
3 Chemical analysis is conducted by EPA and costs are not assigned to the site.
4 Costs are incurred periodically, and the presented costs represent averages between Year 1 and Year 2.
4.4.1
UTILITIES
The primary contributor to utility costs is the electricity required to power the three UV/OX reactors. In
Year 1, three UV/OX units were used at a total of 90 KW, which likely translates to an electricity cost of
approximately $75,000 per year.  The remainder of the electric costs are likely due to the process pumps,
blower motors, and compressor. In Year 2 and future years, the site team plans to reduce the number of
UV/OX units to two, which should reduce electricity costs to approximately $55,000 per year (some of
the electricity costs are due to pumps/motors and will not decrease with bypassing a UV/OX unit).  The
remaining utilities include garbage pickup, maintenance of the cap, phone, and public water.
                                               18

-------
4.4.2          NON-UTILITY CONSUMABLES AND DISPOSAL COSTS

Non-utility consumables represent approximately $106,000 per year in O&M costs for Year 2.
Chemicals for the metals precipitation and peroxide for the UV/OX system are the dominant
consumables costs, and ferric sulfate (for metals removal) is the dominant chemical cost. Of the
remaining $36,000 per year, approximately $16,000 is need for UV/OX maintenance parts. It should be
noted that the above table assumes replacement of one GAC unit per year, primarily due to solids build
up. If solids fouling does not occur with the clay filter removed, GAC replacements may be less
frequent. Because of the extremely low contaminant concentrations entering the GAC, frequent
replacements are not expected due to loading of organic contaminants. Waste disposal costs are about
$55,000 per year and are mainly for disposing of sludge and recovered oil as hazardous waste.

4.4.3          LABOR

Labor contributes more than 50% of the total O&M costs at this site, and is divided into three primary
categories: plant operation, PM/reporting, and ground water sampling/data analysis.  Between Year 1 and
Year 2, plant operation has been reduced by $20,000 for an Year-2 cost of $180,000.  This cost includes
one full-time operator and one part-time engineer that is contributing to system improvements. The
PM/reporting corresponds to approximately $6,500 per month and includes preparation and attendance at
the monthly site meetings, engineering support for improving the treatment plant, and preparing monthly
Discharge Monitoring Reports.  The sampling costs of $75,000 per year include the cost of the NPDES,
quarterly process sampling, and ground water sampling. The  majority of these sampling costs are related
to the ground water sampling and associated data analysis because of the  labor and equipment involved
in low-flow sampling.

4.4.4          CHEMICAL ANALYSIS

Chemical analysis costs are not incurred by the site because EPA conducts the analysis through the
Contract Laboratory Program.
4.5           RECURRING PROBLEMS OR ISSUES

The previous manganese exceedances represent a recurring issue but have been addressed by removing
the clay filter and replacing the carbon in the PDU and GAC units.  Another recurring issue that has been
addressed was the leak detection system response to precipitation inflow. The leak detection system has
been shut down to avoid unnecessary downtime during rain events.

The limiting capacity of the first mixing tank in the metals removal  system is also a recurring issue.
Although the extraction rate is generally between 20 and 25 gpm, the process rate of the treatment plant
is generally higher due to backwashing of filtrate from the filter press, and other recycled water or water
added from outside the system. If the extraction rate is increased in the future, the limiting capacity of
this tank will be problem.

Maintenance issues with the UV/OX system cause excessive down time.  At the time of the OSE, it was
practice to shutdown the entire treatment plant if one of the three UV/OX reactors was not working.
Therefore, when the blower on the third reactor failed, this caused system-wide downtime.  System-wide
downtime was also caused by repeated lamp failures on the second reactor.
                                             19

-------
In general, a number of treatment plant features have required modification or replacement. The absence
of level transmitters, flow meters, and flow controls at various parts of the plant (presumably due to cost-
cutting measures during design and installation) have hampered O&M of the plant and general trouble
shooting. The site team has worked to improve many of these features; nonetheless, issues with original
design and construction (such as limited space and lack of as-built drawings and control system
documentation) repeatedly arise and require both time and expense to address.
4.6          REGULATORY COMPLIANCE

With the exception of the manganese exceedances. which have now been addressed, the system regularly
meets its discharge criteria.
4.7           TREATMENT PROCESS EXCURSIONS AND UPSETS, ACCIDENTAL
              CONTAMINANT/REAGENT RELEASES

No process excursions, accidents, or reagent releases were reported during as part of this optimization
effort.
4.8           SAFETY RECORD

One accident has occurred at the treatment plant. The RPM, while visiting the plant, tripped on the door
jamb and fell down a step resulting in a knee injury. The concrete pad has since been modified to reduce
the tripping hazard, and safety paint has been applied to draw attention to comers, steps, and the door
jamb.
                                          20

-------
     5.0  EFFECTIVENESS OF THE SYSTEM TO PROTECT HUMAN
                       HEALTH AND THE ENVIRONMENT
5.1           GROUND WATER

The interim ground water remedy has accomplished many of its intended goals. The lining of the 30-inch
storm sewer and the installation of the collector drain has reduced transport of contaminated water into
Naylors Run.  Many of the surface water samples now have non-detect results because this portion of the
remedy has functioned as intended.

Despite these success, the interim remedy is likely not suitable as the final remedy without modifications.
First and foremost, the abandoned 12-inch sewer line that was first discovered in 2003 is likely
facilitating transport of PCP and dioxin from ground water to a downgradient location. PCP
concentrations in seeps as high as 750 ug/L have been detected. Human and other receptors can be
exposed to this contamination if it is not controlled or removed.

The current remedy may also not provide adequate capture. Current site conditions (with the exception
of the 12-inch sewer line) suggest that PCP is not reaching  surface water in detectable amounts; however.
if the plume containment is not adequate, contaminated ground water may impact surface water in the
future. The interpreted capture zone, based on fairly preliminary analysis of the March 2003 ground
water elevation data (See Section 4.2.2), appears fairly extensive. However, the interpreted capture zone
based on other data is somewhat less extensive. Furthermore, the vertical extent of the capture zone is
difficult to evaluate and the plume is not fully delineated in both the horizontal (especially to the  south)
and vertical directions.

It is understood that many of these items were not intended as part of OU2 and that they will be
addressed as part of OU3, which represents the final remedy for ground water.
5.2           SURFACE WATER

Conditions in Naylors Run have improved substantially due to the operation of the OU2 interim remedy;
however, portions of Naylors Run still have substantial impacts likely due to a 12-inch sewer line
providing a conduit for contaminated ground water to reach the surface and discharge into Naylors Run.
Seep concentrations of PCP have been as high as 750 ug/L and sediment PCP concentrations have been
as high as 6,200 ug/kg. Dioxin concentrations are also elevated. This area is indicated on Figure 1-1.

Proper sealing of the abandoned sewer line and localized remediation efforts as part of OU3 should be
able to address this  contamination.
5.3           AIR

Due to previous removal actions, air quality is no longer adversely affected by the site.
                                             21

-------
5.4            SOILS

Soils beneath the NWP cap are impacted, but the cap prevents direct contact with these soils. Other soils
downgradient of the cap and along the water table are also likely impacted due to the migration of free
product and the ability of the free product to smear as the water table rises and recedes. These soils
should not be a threat to human health unless there are invasive activities in these areas. Efforts should
likely be taken to delineate these areas and provide institutional controls to notify construction workers
or others that may be involved in these invasive activities.

A greater threat to human health and the environment are the surface soils that are impacted by PCP and
dioxin from the contaminated water that is accumulating in the 12-inch abandoned sewer and discharging
to the surface. These soils are located in a Residential Open Space and are accessible to homeowners in
the area.
5.5           WETLANDS AND SEDIMENTS

The discussion in the above sections regarding the impacted seep also apply to the sediments in this area.
Conditions in the wetlands and sediments will be addressed as part of OU3.
                                              22

-------
                            6.0  RECOMMENDATIONS
Cost estimates provided herein have levels of certainty comparable to those done for CERCLA
Feasibility Studies (-307+50%), and these cost estimates have been prepared in a manner consistent with
EPA 540-R-00-002, A Guide to Developing and Documenting Cost Estimates During the Feasibility
Study, July 2000.
6.1           RECOMMENDATIONS TO IMPROVE EFFECTIVENESS

The recommendations in this section are not intended to imply deficiency of the OU2 remedy.  It is
recognized that the OU2 remedy is an interim measure to address shallow ground water contamination
and its impacts on Naylors Run. Many of these recommendations in this section are offered not as
improvements to OU2 but as considerations for OU3.  Some of these recommendations (particularly
6.1.1), however, should be implemented as soon as possible and potentially as part of an emergency
response.

6.1.1          PROPERLY SEAL ABANDONED 12-INCH SEWER LINE AND REMEDIATE SURFACE SOILS
              NEAR THE SEEP

The site team is already addressing this issue.  The first step involves locating the upgradient portion of
this abandoned sewer line immediately downgradient of the collection drain. It is thought that the line
may have been broken or disturbed during construction of the collection drain, allowing ground water to
infiltrate it.  Once the upgradient portions are located, they  can be evaluated to confirm that this line is
the cause of the impacted seeps further downgradient. Once confirmed, the line and the associated
bedding material should be plugged to prevent further infiltration and transport of contaminated water.
With the line plugged, the seep area can be evaluated to confirm that the discharge has stopped, and then
the contaminated  soils and sediments can be addressed.

This recommendation is of primary importance and should  be done as soon as practicable. Because this
area is considered a Residential Open Space (ROS) and is available to nearby residents, the contaminated
area should be clearly marked to warn residents of the contamination.

The abandoned line has been identified at possibly 9 feet bgs.  Assuming that the line can be found, a dye
test and possibly a video inspection can be used to confirm  the connection to the ROS area. Once
confirmed the line and bedding can be plugged with a cement/bentonite slurry. The length of the line to
be plugged beyond the upgradient end would be determined by the condition and accessibility of the line
between the collection drain and the ROS area. The exact scope of this work cannot be determined at this
point but an expenditure of $50,000 or less might be sufficient to eliminate this preferential pathway.
Once the pathway has been eliminated, contaminated soil and sediment can be delineated and removed
from the ROS; assuming that the amount of material to be removed is less than 500 cubic yards
remediation might be accomplished for about $150,000. Note these cost estimates were not rigorously
determined by the OSE team, and higher costs are possible  (estimates that suggest higher costs should be
thoroughly reviewed).
                                             23

-------
6.1.2           IMPROVE PLUME DELINEATION TO THE SOUTH AND VERTICALLY

Monitoring well clusters CW-4 and CW-5 include the southern most wells at the site, and they are
contaminated with PCP concentrations over 1,000 ug/L.  An additional monitoring well cluster should
likely be placed further south with monitoring wells at the shallow and deep intervals. For cost-
effectiveness, wells at the intermediate elevations can likely be omitted. The optimization team suggests
placing this single cluster (with a shallow and deep well) approximately 250 feet south of CW-4.  This
should place the well on Lawrence Road directly to the south of CW-4.  It is expected that shallow and
deep monitoring wells at this location will yield samples with concentrations of PCP and dioxin that are
undetectable or below MCLs. This would delineate the plume to the south. If concentrations are low,
but above the MCLs, perhaps the southern boundary of the plume can be determined by extrapolation
between CW-4, CW-5, and this new cluster. If extrapolation is unacceptable, then the next likely place
to locate a monitoring well cluster is on Achille Road, directly south of CW-4 and the new cluster.

To delineate the plume vertically, deeper wells should be installed in multiple locations (perhaps up to
four locations). In addition to delineating the plume,  these wells would provide monitoring points to
confirm that the final remedy (when implemented) prevents contamination from migrating at depth. Due
to the high concentrations found as deep as 50 feet below ground surface, it is likely that contamination
is also present from 50 to 60 feet and possibly from 60 to 70 feet. Therefore, for delineation, the
appropriate depths of the wells might be from 70 to 80 feet below ground surface,  but a more appropriate
depth may be determined by the site team after further reviewing historical data and well logs. The well
logs from the construction of the extraction wells may be helpful. Alternatively, drilling techniques
where different depths are sampled as drilling occurs  (to determine a final screen interval), using packers,
can be utilized.

Although the deeper portions of the extraction wells could be sampled to help determine the extent of
vertical contamination, the results would likely be inconclusive. For example, if these deeper samples
are contaminated, the contamination could be due to the following reasons:

•      the lower portion of the  screened interval is hydraulically connected to the upper portion and
       contamination from shallower intervals is being drawn down during sampling

•      the wells have historically acted as conduits for downward migration of contamination, but this
       condition is not representative for other parts of the site

•      contamination has migrated to this depth naturally and may be at this depth (or greater depths at
       other parts of the site)

Because the results would be potentially inconclusive, sampling of the deeper portions of the extraction
wells  is not recommended.

The following are suggested locations for installing deep wells.

Downgradient of the  collector drain beyond the interpreted zone of capture (perhaps 100 to 200 feet
downgradient of the interpreted capture zone) - The collector drain captures contamination from the
overburden and likely from the shallower portions of the bedrock.  A deep well would help determine if
contamination is present at a depth of 70 to 80 feet and migrating beneath the collector drain. To
evaluate capture at slightly shallower depths, this location would also be appropriate for a well screened
at a shallower interval (perhaps 40 to 50 feet).


                                               24

-------
Co-located with CW-9 - CW-9D is approximately 50 feet deep and has PCP concentrations above MCLs.
In addition, CW-9D is downgradient of CW-4D and CW-5D, which have PCP concentrations as high as
5.200 and 1,700 ug/L, respectively.  Co-locating a deep well (approximately 70 to 80 feet deep) with
CW-9D should vertically delineate contamination in this area.  Furthermore, the enhanced CW-9 cluster
(i.e., with wells at three depths) should provide a downgradient monitoring point to confirm that the final
remedy (when implemented) provides capture of the contamination found at CW-4D and CW-5D. If
capture is adequate, concentrations at the three CW-9 wells should decrease to background (i.e., non-
detect) overtime.

Co-located with CW-13 - CW-13D is the deepest downgradient point with contamination above the
MCL.  It had a concentration of 44 ug/L in October 2002.  This deep well should provide vertical
delineation of this contamination. Furthermore, along with the new deep wells at CW-9 and
downgradient of the collector drain, this enhanced CW-13 cluster (i.e., with wells at three depths) should
provide downgradient monitoring points (assuming deep ground water flow is in the same direction as
ground water flow at shallower intervals) to enhance the capture zone evaluation of the final remedy
(when implemented).

Co-located CW-6D - Of the four proposed locations, this is the only location upgradient of the collector
trench. If samples from this new well have low or undetectable concentrations, then this location would
help vertically delineate contamination.  In addition, over time it could be monitored to determine if
contamination is migrating downward.

In general, the proposed well locations have been chosen to both vertically delineate contamination and
to serve as performance monitoring points for the final remedy.  The main presumption is that
contamination at depth will continue to migrate to the southeast (the deep hydraulic gradient can be
evaluated with these new wells) and that as long as these performance monitoring points remain clean or
decrease to background levels, then the plume is adequately contained and further vertical delineation is
not necessary. If this presumption is not sufficient justification, then an additional deep well could be
added at another location such as co-location with CW-2 or CW-3.

In summary, seven monitoring wells have been suggested. Two wells would be part of a cluster to the
south with a shallow and deep well (40 to 50 feet), one is 50 feet deep and downgradient of the collector
drain, and the other four are 80 feet deep. If contamination is found further to the south, an additional
well may also be needed. The depths suggested are preliminary, and drilling techniques where different
depths are sampled as drilling occurs (to determine a final screen interval), using packers, could be
utilized.  The installation and two rounds sampling of the seven proposed wells should cost
approximately $120,000 to $150,000, including a work plan, oversight by a geologist, and a report
describing the delineation of the plume and a proposed target capture zone. Adding annual sampling
these wells to a sampling program would likely increase annual costs by up to $5,000.

6.1.3         EVALUATE PLUME CAPTURE ONCE PLUME is DELINEATED

Once the site team has sufficiently delineated the plume both to the south and vertically, a capture zone
analysis should be conducted.  The capture zone analysis should include a clear statement of the target
capture zone and consist of converging lines of evidence such as those discussed in Section 4.2.2. These
lines of evidence include a water budget analysis, interpretation of capture using the potentiometric
surface maps under pumping conditions, and trend analyses in wells expected to be downgradient of the
capture zone.
                                              25

-------
A ground water flow model with particle tracking could also be applied at this site to evaluate capture.
For evaluating horizontal capture this does not appear necessary, but for evaluating the vertical extent of
capture it may be helpful because the model could be used to help understand vertical ground water flow.
Furthermore, because additional  extraction is likely necessary to provide adequate capture, a flow model
could be helpful in evaluating various pumping scenarios. This is particularly crucial since the treatment
plant has a limited capacity (under 40 gpm), and increasing this capacity significantly could be costly.

The estimated cost for the capture zone analysis without the model is approximately $20,000, including
documentation of this analysis in a report. The development of a well-calibrated flow model, and its use
in evaluating both capture and various extraction scenarios might cost $35,000.

6.1.4          TAKE MEASURES TO FURTHER REDUCE SYSTEM DOWNTIME

The maintenance problems associated with keeping three UV/Oxidation units operating continuously has
resulted in excessive downtime of the system. Using three units in series to meet effluent standards is
unnecessary and the site team is already considering bypassing one unit. Bypassing any number of the
units will allow  a standby unit to be available in case of the unexpected but common downtime of one
operating UV/Oxidation unit. In addition, bypassing two units or all three units (i.e., using GAC for
primary organics treatment) may also be more cost-effective (see section 6.2.1). For the purpose of
reducing system downtime, we recommend that at least two of the units be bypassed. One UV/Oxidation
unit could be kept as a standby unit, and the  third unit could be either kept at the site in reserve or
removed for use at another site. Even with additional flow likely from the final remedy one UV/oxidation
unit followed by GAC polishing  will be a conservative system. The site should also maintain a sufficient
parts inventor}' to allow timely repair and/or replacement of system parts. Maintaining this inventory
will reduce the likelihood that  downtime will occur due to backlogs in obtaining parts.

A few other issues contribute to downtime.  One issue, which is discussed further in Section 6.3.2,
involves modifying the plant to provide storage of backwash waste water. The other pertains to the lack
of documentation associated with the system controls. A number of alarms cause system shut downs,
and in the absence of good documentation for these controls, the site team is in the process of learning
the logic behind the various alarms.  This  issue will be addressed over time given that the site team
continues its efforts to become familiar with the system.

There are no added cost to implementing these steps. There are likely cost reductions associated with
reducing the number of UV/Oxidation units, but these potential saving are discussed in Section 6.2.1.
6.2           RECOMMENDATIONS TO REDUCE COSTS

6.2.1          USE FEWER UV/OXIDATION UNITS

The site team is considering bypassing one of the UV/Oxidation units which will save about $20,000 per
year in electricity, $8,000 in lamps and accessories, and $4,000 per year in hydrogen peroxide.  These
savings are already reflected in Section 4.4 of this report.  Based on the May 2003 process sampling
event, greater than 99.9% of the organics mass removal is achieved in the first UV/OX unit.
                                              26

-------
Parameter
Benzene
Trichloroethylene
Naphtlialene
PCP
Phenanthrene
Maximum Influent
Concentration
9/2002 -6/2003 (ug/L)
12
15
1.800
9,500
400
5/2003
Influent
Concentration
(»g/L)
9.4
13
24
2,900+
25
Effluent After First
UV/OX Unit 5/2003
(ug/L)
ND
0.078 B
ND
2.3 J
0.02 B
NPDES Monthly
Average Effluent
Standard (ug/L)
1
5
30
1
3
B - contaminant found in laboratory blank
J - estimated value
Although the effluent of the first UV/Oxidation unit had a PCP concentration (2.3 ug/L) greater than the
discharge standard, the two 4,000-pound GAC units can easily reduce this concentration below that
standard without increasing the GAC replacement frequency.  Furthermore, at 99.9% removal, one
UV/Oxidation unit would reduce 9,500 ug/L of PCP (i.e.. the maximum influent concentration between
September 2002 and June 2003) to 9.5 ug/L, which can also easily be reduced below discharge standards
with the GAC units without affecting the GAC replacement frequency.  Therefore, two UV/Oxidation
units can be bypassed without sacrificing effectiveness at an additional savings of approximately $32,000
per year relative to the costs reported in Section 4.4 of this report. As mentioned in Section 6.1.4 system
downtime can be reduced by using one of the bypassed units when the operating unit has failed or is
undergoing maintenance.

It is also possible to consider completely bypassing the UV/Oxidation units. For each of the organic
contaminants found in the plant influent above discharge limits, the following table presents the average
influent concentrations between September 2002 and June 2003, the estimated mass loading at a
maximum flow rate  of 40 gpm, a common GAC adsorption isotherm, the ratio of GAC usage to mass
loading, and the estimated GAC per year usage assuming no UV/Oxidation units are operating.
Parameter
Benzene
Trichloroethylene
Naphtlialene
PCP
Phenantlirene
Average Influent
Concentration
9/2002 - 6/2003
(ug/L)
8.72
9.86
277
3,936
2.63
Estimated Mass
Loading
at 40 gpm
(Ibs/year)
1.5
1.7
48.5
688.8
0.5
Isotherm*
0.016xC1/0-40
0.028xC1/a62
0.132xC1/0-42
0.436xC"°-34
0.215xC1/0-44
Ratio of GAC
Usage to
Mass
Loading
(Ibs/lb)
401.5
626.1
13.0
1.4
63.5
Total GAC Usage (Ibs/year)
Estimated
GAC Usage
(Ibs/year)
602
1,064
631
964
32
3,293
* Isotherms from (Dobbs and Cohen, 1980, EPA 600-8-80-023) require contaminant concentration in mg/L and provide the
mass of contaminant sorbed per mass of GAC used. The isotherm for benzene assumes the use ofFiltrsorb 400.

Dioxin is not included in the table because an isotherm could not be located. However, it is generally
understood that GAC is a "best available technology" for dioxin. This is because dioxin is not water
                                               27

-------
soluble and would be removed by removing particles to which it has already sorbed.  Any dissolved
dioxin would be easily sorbed to GAC.

As is evident from the above table, it is estimated that less than 4,000 pounds of GAC would be required
per year to provide treatment in the absence of the UV/Oxidation units. At 40 gpm, a 4,000-pound GAC
unit would provide approximately 25 minutes of residence time, which should be more than adequate for
effective contaminant removal. Ideally, this would translate to replacement of the lead GAC unit once
per year. Practically, however, removal efficiency may decrease as fouling from solids increases.
Therefore, it is reasonable to assume that two replacements of the lead vessel may be required each year.
This is potentially one more unit replacement than anticipated with UV/Oxidation as the primary
treatment. Using GAC alone would therefore save an additional $15,000 per year (approximately) by
eliminating the costs for the final UV/Oxidation unit and the 2,000 pound PDU unit and including the
cost of an additional 4,000-pound GAC replacement.

Prior to fully eliminating the UV/Oxidation units, it is recommended that a thorough pilot test be
conducted. At this time, to avoid a major change to the treatment process, we recommend only bypassing
two UV/Oxidation units with continued consideration of bypassing the UV/Oxidation units completely
once a final remedy extraction system  is determined.

6.2.2          EVALUATE AREAS TO REDUCE LABOR COSTS

The contractor has evaluated and implemented many improvements to the treatment system over the past
year. Monthly site meetings have clearly been very useful in expediting changes and keeping all parties
up to date. However, total labor costs  for running this  system are about $330,000 per year which is
higher than similar systems.  As continued  improvements make the system easier to operate, the  site team
should have a goal of reducing operating labor costs and project management costs. For example, the
monthly site meetings and associated progress reporting can, within a year or two, be reduced to a
quarterly frequency, likely saving approximately $25,000 per year. Reporting and development of work
plans should also become easier over time because site activities will be better understood and less will
change on a monthly basis.  As knowledge  of the treatment plant increases and the need for system
improvements decreases, the level of engineering support (and associated costs) will decrease. The
operator will also be available to conduct other tasks such as NPDES and performance monitoring
sample collection, which is currently part of the sampling task. A total labor cost reduction goal of about
$40,000 per year from the current costs could be used within 1 to 2 years. Adding OU3 flow (if that
occurs as part of the OU3 ROD) may require some minor treatment system modifications and associated
management and labor costs initially but should not increase long term annual labor costs. The site team
has shown decreased labor costs between Year 1 and Year 2 of $25,000, demonstrating that labor costs
will decrease over time and that the  suggested further decrease of $40,000 may be possible of the next
couple of years.
6.3           MODIFICATIONS INTENDED FOR TECHNICAL IMPROVEMENT

6.3.1          CONTINUE IMPROVING TREATMENT PLANT TO FACILITATE OPERATION AND
              POTENTIALLY INCREASE CAPACITY

The treatment system is cramped and performing maintenance is difficult due to the lack of working
space. However, the contractor has already added level transmitters and sight tubes to monitor
operations and many other improvements to operations. The plant continues to have downtime problems
(see Section 6.1.4) and may need minor improvements to handle additional flow if pump and treat is

                                             28

-------
selected as the remedy for OU3 and additional pumping is required. The first metals removal process
tank is currently the limiting unit for hydraulic capacity. Modifying or replacing this tank with a slightly
larger one should be considered. The other reaction tanks may also need modification. The head space
above the tanks and the general working space is limited and will complicate this task, but a solution
should exist such that the current treatment plant can accommodate the necessary flow for OU2, and
possibly OU3 if pump and treat is selected as the OU3 remedy. The tanks are all fiberglass reinforced
plastic. As  an option, a fiberglass  repair contractor (tank, pipe, marine, automotive, etc.) should be able
to modify the tanks to add freeboard. A section could be added to the top of the tank by using fiberglass
cloth and resin around the joint between the existing tank and the new section.  The repair would be
watertight and, due to space limitations, would likely be easier than replacing the tank.  Fiberglass repair
should cost less than $10,000, but tank replacement might cost up to $25,000.

6.3.2          MAKE PIPING CHANGES TO BETTER USE THE SECOND EQUALIZATION TANK

The equalization tank piping should be modified to include a line for potential influent flow directly to
equalization tank #2.  Recycle lines should also be added so that minor maintenance can be accomplished
at equalization tank #1 without shutting down the extraction system.  These piping changes should also
help the current equalization tanks provide some or all of the capacity necessary to store the wastewater
from backwashing. This effort should require less than $10,000 in capital costs.
6.4           CONSIDERATIONS FOR GAINING SITE CLOSE OUT

6.4.1          ADAPT P&T SYSTEM TO Focus PRIMARILY ON COST-EFFECTIVE CONTAINMENT
              WITH DECREASED EMPHASIS ON RESTORATION

Ground water extraction as part of source removal efforts at RW-1 to RW-4 has had limited effectiveness
in terms of mass removal and progress towards restoration, and the existing treatment system limits the
volume of ground water that can be extracted to under 40 gpm. Rehabilitation of the recovery wells, or
other aggressive removal technologies may reduce mass but would not likely significantly shorten the
duration of the pump and treat system. A relatively large area with NAPL and high concentrations at
depth are present and would need to be addressed. Aggressive remediation (other than pumping at the
recovery wells) would therefore require substantial additional cost and interruption of above-ground
activities (e.g., along Eagle Road, at Swiss Farms, and at Young's Produce).  The oil and grease that
comprises much of the NAPL would interfere with aqueous phase reactions (for dehalogenation or
oxidation) and would serve as a scavenger of chemical oxidation chemicals.

For the final remedy, the  site team should consider focusing on hydraulic containment of a targeted
capture zone, even if it means reconsidering ground water extraction in the source area.  LNAPL
collection by product skimming in select locations could be considered and some  ground water removal
could be added over time if containment flow rates allow. No matter what ground water extraction
scheme is applied at the site, restoration to ground water cleanup standards will take many decades to
achieve and capture should not be compromised in the mean time to extract contamination from the
source  area.

By focusing on containment only over a long period of time, monitoring, management, and data analysis
should  be simplified, allowing for O&M costs to be "minimized" for an effective  system. Ground water
monitoring, for example, would be used to demonstrate capture, and monitoring of wells within the heart
of the plume could be decreased in frequency or eliminated altogether. Ground water monitoring could
likely be reduced to sample 50 or 60 samples per year rather than 100  samples per year, yielding potential


                                             29

-------
savings of approximately $30,000 per year. We suggest that EPA and State funds will be utilized in the
most effective manner by containing this site to eliminate the current risks to human health and the
environment. Based on the reported costs in Section 4.4 and the recommendations made in Section 6.2, a
target cost for long-term O&M of a containment-only system might be $500,000 or less per year to be
achieved within 1 to 2 years of the final remedy becoming operational and functional.  After considering
the potential savings in Section 6.2, implementing this recommendation might save an additional $30,000
relative to the costs presented in Section 4.4 of this report.

6.4.2           POTENTIAL OPTIONS FOR IMPROVING CAPTURE

Capture of the fully delineated plume may require additional measures. To the south, there are elevated
concentrations at the CW-4 and CW-5 clusters and delineation is not complete.  Downgradient of the
collector drain, there are PCP concentrations as high as 44 ug/L. The extent to which capture needs
improvement will not be fully known until completion of recommendations 6.1.2 and 6.1.3.

To the south, installation of another downgradient collection drain does not appear to be feasible due to
access considerations. Therefore, containment may require additional extraction wells south of the
existing drain. These wells will likely have to be screened across the shallow and deep zones to allow
the drawdown necessary to achieve flow rates required for containment. Pumped ground water from
these wells can likely be combined  in a header line and added to the flow from the collection drain.  The
1-inch pipe that restricts flow near the drain should be replaced.  The current treatment system will likely
have adequate capacity for this additional flow, especially if the  mixing tanks are modified as suggested
in Section 6.3.1. The additional extraction and should not significantly increase the annual O&M costs.

Downgradient of the collector drain, it is uncertain if remediation or capture is required.  To date,
remediation efforts have not focused on the contamination at CW-9D and CW-13D. EPA appears to
have a few options for addressing this downgradient contamination.

•      Monitor existing and suggested monitoring wells to determine if concentrations are naturally
       attenuating

•      Conduct temporary extraction events at this location to see if concentrations can be permanently
       reduced

•      Install permanent extraction capabilities near CW-13D and pipe that extracted water to the
       upgradient extraction system (i.e., the trench and any new upgradient extraction wells)

•      Inject nutrients or chemical reagents to enhance degradation of that contamination

Because this downgradient contamination appears fairly isolated, it would be difficult to monitor the
effectiveness of any of the  above  approaches without either relying on CW-9D and CW-13D alone or
installing additional monitoring wells.  The decision on how to proceed may depend on the results of
sampling some of the recommended wells (see Section 6.1.2). Assuming no additional contamination is
found at depth, it might be  most appropriate to monitor these downgradient wells (perhaps semi-
annually) for two years to determine if there is a trend. If there is a decreasing trend, it may be
reasonable to let that contamination attenuate.  If there is persistent contamination, it may be reasonable
to attempt one year of quarterly temporary extraction events. If concentrations are increasing and/or the
temporary extraction events are unsuccessful, then either permanent extraction or the injection of
nutrients/reagents should be considered. Permanent extraction would likely require well over $100,000
in capital costs. The injection of nutrients/reagents might include lactate, molasses, or even nano-scale


                                               30

-------
iron (ARS Technologies or PARS Environmental) to foster reductive dechlorination.  It should be noted,
however, that the injection of nutrients/reagents (especially nano-scale iron) for enhancing the reductive
dechlorination of PCP is in a experimental stage. Therefore, if this approach is taken, appropriate testing
and piloting should be conducted prior to full-scale implementation. The costs for these options would
vary but would might be under $100.000 for a few injection events in a one or two existing wells over the
course of a year, especially if monitoring is limited (i.e., limited to the  injection well and/or one
additional downgradient well).
6.5           SUGGESTED APPROACH TO IMPLEMENTATION

Addressing the abandoned sewer line preferential pathway (Section 6.1.1) is ongoing and is of the
greatest importance for risk minimization. These activities should be completed as soon as possible. If
the preferential pathway is eliminated plume delineation and completion of plume capture evaluation
(Sections 6.1.2 and 6.1.3) can be completed as part of the OU3 activities.  We have identified several
delineation issues to consider in Section 6.1.2.

There is strong evidence to support bypassing two of the UV/Oxidation units (Section 6.2.1)
immediately.  In addition to achieving cost savings without any negative impact on protectiveness
bypassing these units will improve the poor system downtime record (Section 6.1.4).

The remaining recommendations are related to or can be considered and implemented in concert with
selecting an OU3 remedy.
                                             31

-------
                                     7.0   SUMMARY
The evaluation team observed a conscientious and knowledgeable site team (i.e., EPA and its contractor)
that has effectively managed this interim remedy, provided a number of much needed plant
improvements, and initiated the remedial investigation for OU3.  The observations and recommendations
contained in this report are not intended to imply a deficiency in the work of either the system designers
or operators but are offered as constructive suggestions in the best interest of the EPA and the public.
These recommendations have the obvious benefit of being formulated based upon operational data
unavailable to the original designers.

Recommendations to improve effectiveness include proceeding with the investigation and proper
abandonment of the sewer lines that led to downgradient contamination and remediation of the associated
soils and sediments. Other effectiveness recommendations include delineating the contaminant plume,
conducting a capture zone evaluation, and reducing system downtime.  Specific items for  each of these
recommendations are provided. Recommendations for reducing cost include bypassing two of the
UVYOxidation units and reducing O&M labor.  Recommendations for technical improvement include
modifying the metals removal mixing tanks to allow increased flow, and modifying the equalization tanks
to improve flexibility in operation and reduce downtime. Finally, recommendations associated with site
closeout include focusing the remedy on containment rather than restoration and a discussion of options
for potentially improving containment to the south and/or downgradient of the current extraction system,
if determined to be necessary after the recommended capture zone analysis is completed.

Table 7-1 summarizes the costs and cost savings associated with each recommendation. Both capital and
annual costs are presented.  Also presented is the expected change in life-cycle costs over a 30-year
period for each recommendation both with discounting (i.e., net present value) and without it.
                                              32

-------
                                    Table 7-1. Cost Summary Table
Recommendation
6.1.1 Properly Seal
Abandoned 12 -Inch Sewer
Line and Remediate Surface
Soils Near the Seep
6.1.2 Improve Plume
Delineation to the South and
Vertically
6.1.3 Evaluate Plume
Capture Once Plume is
Delineated
6.1.4 Take Measures to
Further Reduce System
Downtime
6.2.1 Use Fewer
UV/Oxidation Units
6.2.2 Evaluate Areas to
Reduce Labor Costs
6.3.1 Continue Improving
Treatment Plant to Facilitate
Operation and Potentially
Increase Capacity
6.3.2 Make Piping
Changes to Better Use the
Second Equalization Tank
6.4. 1 Adapt P&T System
to Focus Primarily On
Cost-Effective Containment
with Decreased Emphasis on
Restoration
6.4.2 Potential Options for
Improving Capture
Reason
Effectiveness
Effectiveness
Effectiveness
Effectiveness
Cost
Reduction
Cost
Reduction
Technical
Improvement
Technical
Improvement
Site Closeout
Site Closeout
Additional
Capital
Costs
($)
$200,000
$120,000
to
$150,000
$55,000
$0
$0
$0
<$ 10,000
to
$25,000
$10,000
$0
Estimated
Change in
Annual
Costs
(S/yr)
$0
$5.000
$0
$0
($32,000)
($40,000)
$0
$0
($30,000)
Estimated
Change
In Life-cycle
Costs
($)*
$0
$285,000
$55,000
$0
($960,000)
($1,200,000)
<$ 10,000
to
$25,000
$10,000
($900,000)
Estimated
Change
In Life-cycle
Costs
($)**
$0
$216,000
$55,000
$0
($516,000)
($646,000)
< $10,000
to
$25,000
$10,000
($484,000)
Contingent on results from implementing 6. 1.2 and 6.1.3
Costs in parentheses imply cost reductions.
* assumes 30 years of operation with a discount rate of 0% (i.e., no discounting)
** assumes 30 years of operation with a discount rate of 5% and no discounting in the first year
                                                   33

-------
FIGURES

-------
                             FIGURE 1-1. THE HAVERTOWN PCP SITE AND THE SURROUNDING AREA.
                     GROUNDWATER
                     TREATMENT PLANT
  CW-14S
*CW-14D
                        HAVERTOWN PCP
                        SUPERFUND SITE CAP
                  SWISS FARMS
     YOUNG'S PRODUC
      FOR WELL LOCATIONS IN
      THIS AREA SEE FIGURE 1-2
                            LEGEND:

                   CW-7D   EXISTING MONITORING
                     9      WELL
                              400
                          SCALE IN  EEET
800
           CW-7D
           &
        CW-7S
         PHILADELPHIA
         GUM COMPANY
                                                          \
                                                             COLLECTOR
                                                             TRENCH
                                                               CW-13'S
                                                               CW-13D
 (Note: This figure is developed from site figures provided by Tetra Tech, June 2003.)
                                                                                                              -N-
                                                                                           NAYLOR'S  RUN
                                                                                        CW-12S     Jj
                                                                                        CW-12D    ;fr

                                                                                               ,//	i
                                                         LOCATION  OF  IMPACTED
                                                         GROUNDWATER SEEPS
                                                                                                               CW-15S

-------
                             FIGURE 1-2. AREA IMMEDIATELY SURROUNDING THE FORMER NWP FACILITY.
  -N-
         GROUNDWATER
       TREATMENT PLANT
     CW-1S
      CW-11
       CW-1D
      NW-6-81
                                     CW-21
                                         <
                HAVERTOWN  PCP      CW-2D
              SUPERFUND SITE  CAP
SWISS FARMS
                                            CW-2S
                                             RW-1
                                NW-1-81
                                                                                          LEGEND:

                                                                                  CW-3D   EXISTING MONITORING
                                                                                    ®     WELL
                                                                                  MW-23
                                                                                          RECOVERY WELL
                                              CW-3D
                                                CW-3I
                                                 CW-3S
                                                                                 CW-8S
                                                                                      $

                                                                               CW-8D
               YOUNG'S  PRODUCE       /   /'' HAV-02,

                   >^  \   RW-4/   /       /     PHILADELPHIA GUM COMPANY
                    R-4
                 CW-4S
                   CW-4I
                     CW-4D
                                                                                       CW-6I
                                                                                     CW-6D
                                                                                          EW-1
                                                                                              CW-6S
                                                                       EW-2®

                                                                      COLLECTOR
                                                                       TRENCH /
                                                                      «
                                                                                                          NAYLOR'S RUN
                                                                                 HAV-04
                                                                                                   PZ-'
                                                                                               PZ-2
                                                                                  HAV-05
                                                                                                           HAV-07
                                                      CW-5S
                                                        CW-5I
                                                          CW-5D
                                                                            CW-9D
                                                                                     CW-9S
       0          125
              SCALE  IN FEET
      250
                                                                                                               CW-10D
(Note: This figure is developed from site figures provided by Tetra Tech, June 2003.)

-------
                           FIGURE 1-3. EXTENT OF PCP CONTAMINATION IN THE SHALLOW ZONE (APPROXIMATELY 5 TO 20 FEET BGS).
         O
            CW-14S
                              CW-1S
                                NW-6-81
             LEGEND:


             FREE PRODUCT


             >1,000 ppb


             100  ppb to 1,000 ppb


             10 ppb to 100 ppb
                                                                o,
                         CW-7D
                         CW-7S
   CW-2S  ANW_1_81
                                                         Qcw-
                      5S
o,
                                                                          CW-8S
                                                                  CW-6S
                                                    LHAV-02

                                                             HAV-05
                                              CW-4S
                                                   CW-5S
                                                             CW-9S
                                                                  CW-1
      SYMBOLS ARE BASED ON THE MAXIMUM DETECTED CONCENTRATION
      FROM SAMPLING EVENTS BETWEEN  2000 AND  MARCH 2003. EXTENT
      OF PCP CONTAMINATION  IS  NOT NECESSARILY INDICATIVE OF EXTENT
      OF DIOXIN CONTAMINATION.
                               o
                              CW-13S
                                                                                    O
                                                                                CW-11S
                                            -N-
                                                      o
                                                        CW-12S
                            400
                       SCALE IN FEET
800
                                                                            CW-15S
                                                                            O
(Note: Tliis figure is generated from base maps and sampling data provided by Tetra Tech.)

-------
                      FIGURE 1-4. EXTENT OF PCP CONTAMINATION IN THE DEEP ZONE (APPROXIMATELY 35 TO 60 FEET BGS).
    O
       CW-14D
                                                  •'CW-3D
                   OCW-
                                                                         SD
                               O
                                  CW-1D
                                                                .EW-3
                                                                   -N-
        LEGEND:


        FREE PRODUCT


        >1,000 ppb


        100  ppb to 1,000 ppb


        10 ppb to 100 ppb
  O
                                        'CW-4D
                                               CW-5D
                                                         EW-1
                                                         CW-9D
                                                                   CW-10D
                      O
                     CW-13D
                                                                                 O
                                     CW-11D
                                             Q
                                                                                              CW-12D
 SYMBOLS ARE BASED ON THE MAXIMUM DETECTED CONCENTRATION
 FROM SAMPLING EVENTS BETWEEN  2000 AND MARCH 2003. EXTENT
 OF PCP CONTAMINATION IS NOT NECESSARILY INDICATIVE OF EXTENT
 OF DIOXIN CONTAMINATION.
                                 400
                             SCALE  IN FEET
800
(Note: This figure is generated from base maps and sampling data provided by Tetra Tech.)

-------
            FIGURE 4-1. POTENTIOMETRIC SURFACE FOR SHALLOW GROUNDWATER UNDER PUMPING CONDITIONS (APPROXIMATELY 5 TO 20 FEET BGS).
      CW-14S
               o
               o
                                                                                      INTERPRETED
                                                                                      CAPTURE ZONE
                                 INTERPRETED
                                 CAPTURE ZON
                               400
                          SCALE  IN FEET
800
                                                                                                                        -N-
(Note: TMs figure is developed from a potentiometric surface map generated by Tetra Tech using March 2003 ground water data.)

-------
          FIGURE 4-2. POTENTIOMETRIC SURFACE FOR DEEP GROUNDWATER UNDER PUMPING CONDITIONS (APPROXIMATELY 40 TO 50 FEET BGS).
                                                                   CW-7D
           CW-14D
      o
      o
      ro
                                                  ^-®
                                                   CW-5D  / CVJ~
                                                              flr
                                                 o
                                                 en
                                                 CM

                                           INTERPRETED

                                           CAPTURE ZONE-
                                                               
-------