Final Report
Pilot Region-Based Optimization
Program for Fund-Lead Sites
in EPA Region 3
Site Optimization Tracker:
Croydon TCE Site
Bristol Towns, Pennsylvania
EPA Region III
-------
Solid Waste and EPA 542-R-06-006I
Emergency Response December 2006
(5102P) www.epa.gov
Pilot Region-Based Optimization Program
for Fund-Lead Sites in EPA Region 3
Site Optimization Tracker:
Croydon TCE Site
Bristol Towns, Pennsylvania
EPA Region III
-------
Site Optimization Tracker:
Croydon TCE Site
Bristol Towns, 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
Croydon TCE I
4a. EPA RPM
Kelley Chase (used to be Jill
Lowe)
4b. EPA RPM Phone Number
215-814-3124
4c. EPA RPM Email Address
chase.kelley@epa.gov
Site Location (city and State) 3. EPA Region
ristol Township, PA 3
5a. State Contact
Mark Conaron
5b. State Contact Phone Number
484-250-5730
5c. State Contact Email Address
mconaron@state.pa.us
5. Is the ground water remedy an interim remedy or a final remedy? Interim! | Final IXI
6. Is the site EPA lead or State-lead with Fund money? EPA |/\l State I I
B. General Site Information
1 a. Date of Original ROD for Ground Water Remedy
06/29/90
2a. DateofO&F
11/21/95
3. What is the primary goal of the P&T system
(select one)?
1 1 Contaminant plume containment
1 1 Aquifer restoration
IXI Containment and restoration
1 I Well-head treatment
lb. Dates of Other Ground Water Decision Documents (e.g., ESD, ROD Amendment)
ROD OU1 - 12/28/88; ESD OU2 12/31/96
2b. Date for transfer to State
11/21/2005
4. Check those classes of contaminants that are
contaminants of concern at the site.
K| VOCs (e.g., TCE, benzene, etc.)
n 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 I I No IXI
6. What is the approximate total pumping rate? 62 gpm
7. How many active extraction wells ,
(or trenches) are there?
9. How many samples are collected
from monitoring wells or piezometers .
each year? (e.g., 40 if 10 wells are
sampled quarterly)
11. What above-ground treatment processes are usec
IXI Air stripping
I | Carbon adsorption
1 I Filtration
IXI Off-gas treatment
1 I 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)?
1 I Metals precipitation
I | Biological treatment
O UV/Oxidation
I | Reverse osmosis
O Other
12. What is the approximate percentage of system downtime per year? 10% IXI 10-20%| | >20% | |
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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
$31,500
$31,000
$27,000
$16,300
$4,600
$0
$7,600
$7,500*
$9,400
$134,900
Estimated2 Annual
Costs for FY05
$32,000
$32,000
$27,000
$17,000
$5,000
$0
$8,000
$7,500*
$10,000
$138,500
Estimated2 Annual
Costs for FY06
**
**
**
**
**
**
**
**
**
**
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
**
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. FY04 Costs, with the exception of the analytical costs, were provided by the RPM.
2. FY05 costs are based on projections by the RPM and discussions during the optimization follow-up meetings.
* 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 will likely be incurred by the State when the site is transferred to the State after LTRA.
The decrease from FY05 to FY06 reflects the assumed sampling reduction.
** FY06 costs are not provided because the site will be largely managed and financed by the State. Contractors
and contractor costs may be different than those under EPA management.
- "Labor: Ground water sampling" includes shipment of samples, sampling supplies, rental of field instruments,
and travel expenses.
- "Labor: Reporting" includes preparation of Annual O&M Report.
- "Utilities: Other" includes lawn mowing, and site security.
- "Disposal Costs" includes annual cleaning of AST, replacement and disposal of GAC.
- "Other Costs" (2004) includes replacement of blower and well repair.
-------
D. Five-Year Review
1. Date of the Most Recent Five-Year Review 12/12/2001
2. Protectiveness Statement from the Most Recent Five-Year Review
I | Protective I I Not Protective
M Protective in the short-term Determination of Protectiveness Deferred
3. Please summarize the primary recommendations in the space below
Implement 1C to prohibit use of ground water
Enlarge ground water monitoring program
Renegotiate access
Optimize operation & effectiveness of P&T
Prepare for PADEP takeover in Novemeber 2005
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.
There is a PRP plume associated with Rohm and Haas plant on other side of creek.
This PRP plume has TCE, plus ammounium sulfate. So far ammonium sulfate has not
impacted Croydon Site wells.
The site is scheduled for transfer in November 2005, indicating that the site will likely be
managed by the State during any subsequent follow-up events.
-------
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
December 1, 2004 (Evaluation meeting)
August 5, 2005 (Final Report)
Meeting Date
July 20, 2005
October 19, 2005
Report Date
Item
August 5, 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
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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)
Croydon TCE Site
December 30, 2005
October 19, 2005 - Meeting
ROET MEMBERS CONDUCTING THE FOLLOW-UP EVALUATION:
Name
Norm Kulujian
Kathy Davies
Paul Leonard
Peter Ludzia
Peter Rich
Rob Greenwald
Doug Sutton
Kathy Yager
Steve Chang
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. EPAOSRTI
Phone
215-814-3130
215-814-3315
215-814-3350
215-814-3224
410-990-4607
732-409-0344
732-409-0344
617-918-8362
703-603-9017
Email
kjdujiajuiQjTn@jsrja.gQY
davies .kathy@epa. gov
feMBIlijliMJ^iSllLSfiY
ludzia.peter@epa. gov
ElMl@SISl21Jl>iJlLSM
rgrccnwald@gcotransinc.com
dsutton@.ggoliansinc.com
yagcr.kathlccn@cpa.gov
chang._sjcyciij7ici)agov
SITE TEAM MEMBERS (INCLUDING CONTRACTORS) INTERVIEWED
Name
Kelley Chase
Bruce Rundell
Affiliation
U.S. EPA Region 3 (RPM)
U.S. EPA Region 3 (Hydro)
Phone
215-814-3124
215-814-3317
Email
chase.kelleviS-epa.gov
rundell.bruce@epa.gov
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IMPLEMENTATION STATUS OF ALL RECOMMENDATIONS UNDER CONSIDERATION BUT NOT
PREVIOUSLY IMPLEMENTED
Recommendation
Recommendation
Reason
E-2.1 Work with County to Institute Institutional Controls
Protectiveness
Implementation
Status
Deferred to State
Comments: The site team has not made progress on this recommendation. Now that the site has transferred,
EPA will need to work with the State regarding appropriate institutional controls. In addition, after further
review of the ROD, EPA is not completely sure that institutional controls are required by the ROD.
Recommendation
Recommendation
Reason
£-2.2 Extend Access Agreement with Rohm and Haas
Protectiveness
Implementation
Status
Deferred to State
Comments: Now that the site has transferred to the State, EPA no longer needs site access. The State will need
to move forward with obtaining access.
Recommendation
Recommendation
Reason
E-5.1 Defer P&T System Exit Strategy to After Transfer of the Site to the State
Site Closeout
Implementation
Status
Comments: EPA has deferred development of an exit strategy to the State.
Implemented
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-3.1 Reduce Process Monitoring
Cost Reduction
Implementation
Status
Will not be implemented
Comments: The State will not deviate from the current process monitoring program for both aqueous and vapor
sampling.
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
It was reported during the follow-up meeting that the State is scheduled to take over the
site in November 2005.
NEW OR UPDATED RECOMMENDATIONS FROM THIS FOLLOW-UP
None.
-------
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)
Croydon TCE Site
August 5, 2005
July 20, 2005 - Meeting
ROET MEMBERS CONDUCTING THE FOLLOW-UP EVALUATION:
Name
Norm Kulujian
Kathy Davies
Paul Leonard
Peter Rich
Rob Greenwald
Doug Sutton
Affiliation
U.S. EPA Region 3
U.S. EPA Region 3
U.S. EPA Region 3
GeoTrans, Inc.
GeoTrans, Inc.
GeoTrans, Inc.
Phone
215-814-3130
215-814-3315
215-814-3350
410-990-4607
732-409-0344
732-409-0344
Email
kuluiian.nonTVtficpa.gov
dayics.katlTyjtfjcp_a.gov
Leonard. paul@epa.gov
pricli@geotraiisiiic.coin
rgreenwald@geotraiisinc.coin
dsu tton@geotransinc.coni
SITE TEAM MEMBERS (INCLUDING CONTRACTORS) INTERVIEWED
Name
Kelley Chase
Bruce Rundell
Colleen Becker
Affiliation
U.S. EPA Region 3 (RPM)
U.S. EPA Region 3
(Hydrogeologist)
U.S. EPA Region 3
Phone
215-814-3124
215-814-3317
Email
dliSLMllSISSJIiigSY
rundell.bruce@epa.gov
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IMPLEMENTATION STATUS OF PREVIOUSLY IDENTIFIED RECOMMENDATIONS
Recommendation
Recommendation
Reason
2.1 Work with county to Institute Institutional Controls
Protectiveness
Implementation
Status
Under consideration
Comments: Update status during next follow-up.
Recommendation
Recommendation
Reason
2.2 Extend Access Agreement with Rohm and Haas
Protectiveness
Implementation
Status
Under consideration
Comments: Update status during next follow-up.
Recommendation
Recommendation
Reason
3.1 Reduce Process Monitoring
Cost Reduction
Implementation
Status
Will not be implemented
Comments: RPM indicates that State is not inclined to deviate from the current process monitoring.
Recommendation
Recommendation
Reason
5.1 Defer P&T System Exit Strategy to After Transfer of the Site to the State
Site Closeout
Implementation
Status
In Progress
Comments: EPA and PADEP are coordinating regarding the best approach for the P&T system exit strategy.
-------
OTHER CHANGES, UPDATES, OR SIGNIFICANT FINDINGS SINCE LAST FOLLOW-UP
None.
NEW OR UPDATED RECOMMENDATIONS FROM THIS FOLLOW-UP
None.
-------
UPDATED COST SUMMARY TABLE
Recommendation
Reason
Implementation
Status
Estimated
Capital Costs
($)
Actual Capital
Costs
($)
Estimated Change
in Annual Costs
($/yr)
Actual Change in
Annual Costs
(S/yr)
Original Optimization Evaluation Recommendations
2.1 Work with County to
Institute Institutional Controls
2.2 Extend Access Agreement
with Rohm and Haas
3 . 1 Reduce Process Monitoring
5 . 1 Defer P&T System Exit
Strategy to After Transfer of the
Site to the State
Protectiveness
Protectiveness
Cost Reduction
Site Closeout
Deferred to State
Deferred to State
Will not be
implemented
Implemented
$15,000
Not quantified
$0
$0
$0
$0
Not quantified
($2,000)
($80,000)*
$0
New or Updated Recommendations from Follow-up #1, July 20, 2005
None.
New or Updated Recommendations from Follow-up #2, October 19, 2005
None.
Costs in parentheses imply cost reductions.
* Potential savings that might be implemented if the P&T system is shut down and the site is still managed with monitoring and reporting.
-------
APPENDIX: A
ARCHIVE OF TECHNICAL ASSISTANCE PROVIDED BY THE ROET
Note: Technical assistance items are provided in reverse chronological order.
-------
Technical assistance has not been provided by the ROET to date.
-------
APPENDIX: B
BASELINE SITE INFORMATION SHEET AND
OPTIMIZATION EVALUATION REPORT
-------
Streamlined
Optimization Evaluation Report
Croydon TCE Site
Bristol Towns, Pennsylvania
EPA Region III
August 5, 2005
-------
SECTION 1:
BASELINE SITE INFORMATION FORM
-------
Date: 1/14/05
Filled Out By: GeoTrans
A. Site Location, Contact Information, and Site Status
1 . Site name 2. Site Location (city and State)
Croydon TCE Bristol Township, PA
4a. EPA RPM 5a. State Contact
Kelley Chase (used to be Jill , . , ~
T \ MarkConaron
Lowe)
3. EPA Region
3
4b. EPA RPM Phone Number 5b. State Contact Phone Number
215-814-3124 484-250-5730
4c. EPA RPM Email Address 5c. State Contact Email Address
chase.kelley@epa.gov mconaron@state.pa.us
5. Is the ground water remedy an interim remedy or a final remedy? Interim! | Final IXI
6. Is the site EPA lead or State-lead with Fund money? EPA |/\l State I I
B. General Site Information
1 a. Date of Original ROD for Ground Water Remedy
06/29/90
2a. DateofO&F
11/21/95
3. What is the primary goal of the P&T system
(select one)?
1 1 Contaminant plume containment
1 1 Aquifer restoration
IXI Containment and restoration
1 I Well-head treatment
lb. Dates of Other Ground Water Decision Documents (e.g., ESD, ROD Amendment)
ROD OU1 - 12/28/88; ESD OU2 12/31/96
2b. Date for transfer to State
11/21/2005
4. Check those classes of contaminants that are
contaminants of concern at the site.
K| VOCs (e.g., TCE, benzene, etc.)
n 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 I I No IXI
6. What is the approximate total pumping rate? 62 gpm
7. How many active extraction wells ,
(or trenches) are there?
9. How many samples are collected
from monitoring wells or piezometers .
each year? (e.g., 40 if 10 wells are
sampled quarterly)
11. What above-ground treatment processes are usec
IXI Air stripping
I | Carbon adsorption
1 I Filtration
IXI Off-gas treatment
1 I Ion exchange
8. How many monitoring wells are regularly _ _
sampled?
10. How many process monitoring samples jj
(e.g., extraction wells, influent, effluent, etc.)
are collected and analyzed each year? (e.g., 24 "
if influent and effluent are sampled monthly) terly
(check all that apply)?
1 I Metals precipitation
I | Biological treatment
O UV/Oxidation
I | Reverse osmosis
O Other
12. What is the approximate percentage of system downtime per year? 10% IXI 10-20%
n >2o% n
-------
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
Actual Annual Costs
for FY03
$37,500
$31,000
$17,700
$13,800
$4,700
$0
$0
$5,500
$11,000
$121,200
Actual Annual Costs
forFY04
$31,500
$31,000
$21,000
$16,300
$4,600
$0
$7,600
$6,000
$9,400
$127,400
Projected Annual
Costs for FY05
$32,000
$32,000
$21,000
$17,000
$5,000
$0
$8,000
$6,000
$10,000
$131,000
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
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:
Labor Reporting(2003): Includes preparation of QAPP/FSP and Annual O&M Report
Labor Reporting(2004): Includes preparation of Annual O&M Report.
Utilities: Others: Also includes lawn mowing, and site security.
Disposal Costs (2004): Includes annual cleaning of AST, replacement and disposal of
GAC
Analytical Costs: Includes only shipment of samples, sampling supplies, rental of field
instruments, and travel expenses. Analytical costs are paid by ASQAB.
Other Costs (2003): Includes repair of control panel.
Other Costs (2004): Includes replacement of blower and well repair.
-------
D. Five-Year Review
1. Date of the Most Recent Five-Year Review 12/12/2001
2. Protectiveness Statement from the Most Recent Five-Year Review
I | Protective I I Not Protective
M Protective in the short-term Determination of Protectiveness Deferred
3. Please summarize the primary recommendations in the space below
Implement 1C to prohibit use of ground water
Enlarge ground water monitoring program
Remegotiate access
Optimize operation & effectiveness of P&T
Prepare for PADEP takeover in Novemeber 2005
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.
There is a PRP plume associated with Rohm and Haas plant on other side of creek.
It also has TCE, plus ammounium sulfate. So far ammonium sulfate has not impacted
Croydon Site wells.
-------
SECTION 2:
STREAMLINED OPTIMIZATION EVALUATION
FINDINGS AND RECOMMENDATIONS
-------
Date of Evaluation Meeting:
Croydon TCE Site
December 1, 2004 Date of Final Report: Augusts, 2005
ROET MEMBERS CONDUCTING THE STREAMLINED OPTIMIZATION EVALUATION:
Name
Kathy Davies
Norm Kulujian
Peter Schaul
Peter Rich
Rob Greenwald
Kathy Yager (by phone)
Steve Chang (by phone)
Affiliation
U.S. EPA Region 3
U.S. EPA Region 3
U.S. EPA Region 3
GeoTrans, Inc.
GeoTrans, Inc.
U.S. EPAOSRTI
U.S. EPAOSRTI
Phone
215-814-3315
214-814-3130
215-814-3183
410-990-4607
732-409-0344
617-918-8362
Email
Davies.kathv@epa.gov
Kiiluiian.nomi@cpaa.sov
gghaul.pjC|ci@c|)a._goy
prich@geotraiisinc.com
rgreeiiwald@geotransinc.coni
Yagcr.KatMggJl@gB9--gg|Y
Oiang.stcvc@cpamail.cpa.gov
SITE TEAM MEMBERS (INCLUDING CONTRACTORS) INTERVIEWED
Name
Bruce Rundell
Tony Dappolone
Kelley Chase
Jill Lowe
Harish Mital
Mark Conaron
Tim Cherry
Affiliation
U.S. EPA Region 3 (Hydro)
U.S. EPA Region 3 (Sec.
Chief)
U.S. EPA Region 3 (RPM)
U.S. EPA Region 3 (old RPM)
Tetra Tech
PADEP
PADEP
Phone
215-814-3317
215-814-3188
215-814-3124
215-814-3123
302-738-7551
484-250-5730
484-250-5728
Email
mndcn_j}rucc@CBa._goy
dj^)QaloJleJU!lhonvIjZ)eJ)aJ£Ov
chasc.Milcy.@:cpa.,.gOY
lowe.jill@epa.gov
liarish.inital@tetratecli.coin
mconaroiiMsiatcja.M
icjicmi@giato.pa.us
-------
1.0 SIGNIFICANT FINDINGS BEYOND THOSE REPORTED ON SITE INFORMATION FORM
The evaluation team observed an RPM who appears to be an effective manager of a complex site,
making decisions based on a comprehensive understanding of the site that considers the
hydrogeology, engineering, costs, and relationships with other entities. The RPM appears to
effectively utilize Regional technical resources (e.g., hydrogeologists), and Regional Management
appears to be well informed regarding site progress. The observations and recommendations herein
are not intended to imply a deficiency in the work of either the designers or operators, but are
offered as constructive suggestions in the best interest of the EPA and the public. Recommendations
made herein obviously have the benefit of site characterization data and the operational data
unavailable to the original designers.
Findings beyond those reported on the site information form include the following:
The site is located west of Hog Run Creek, and ground water flows east towards the creek and its
tributaries. The primary contaminant, TCE, is also found in a separate plume located on the
other side of Hog Run Creek which is being addressed by a private party (Rohm & Haas). The
ROD only pertains to the plume west of Hog Run Creek. The plume east of Hog Run Creek also
contains ammonium sulfate, and monitoring to date does not indicate impacts from ammonium
sulfate west of Hog Run Creek (i.e., the P&T system for the Croydon TCE site does not appear
to be drawing ammonium sulfate from the other side of the creek).
The OU-2 ROD specifies ground water cleanup goals based on background, and subsequent to
the ROD, PADEP issued new statewide health standards for ground water remediation that are
less stringent but still protective of human health (e.g., TCE cleanup goal in the ROD is 1 ug/1,
but under newer standards it would be 5 ug/1). Although there is general agreement that
changing the ROD to these newer standards would be appropriate, no action has yet been taken
in this regard. EPA would need to issue an appropriate decision document to change the ground
water cleanup standards for the site.
The ROD calls for institutional controls, but no progress has yet been made regarding instituting
institutional controls. However, OU-1 included the extension of a waterline to potentially
impacted residences, and during the 5-year review in 2001 it was verified during a site visit that
existing residences did match the customer address of the water company. It is reported that no
new users of ground water in the potentially impacted area are evident. EPA suggested during
the evaluation meeting that the County is the most likely entity to get institutional controls
established.
The contaminant of primary concern is TCE. Concentrations are relatively low. In 2003 the
maximum TCE concentration in a monitoring well was 16 ug/1. The maximum observed TCE
concentration in a monitoring well has been declining:
o 48 ug/1 in 1997-98
o 44 ug/1 in 1999
o 39 ug/1 in 2000-01
o 29 ug/1 in 2002
o 16 ug/1 in 2003
-------
TCE concentrations are no longer measured at individual extraction wells, but are measured in
observation wells located near extraction wells. Influent TCE concentration to the treatment
plant is also quite low, and averaged approximately 15 ug/1 in 2003. Changes in average influent
concentration over time are reported as follows:
o 24 ug/1 in 1996
o 24.4 ug/1 in 1998
o 14 ug/1 in 2000
o 12 ug/1 in 2001-02
o 15 ug/1 in 2003
There are little or no TCE daughter products observed. This suggests that concentration
reductions over time are likely due to some combination of mass removal caused by pumping
and/or natural processes such as dilution from net recharge and dispersion, but not largely due to
biodegradation. The degree to which pumping is the cause of the observed concentration
decreases, relative to other natural processes, is not easily determined.
Given the pumping rate of 60-70 gpm from the 6 extraction wells, and an influent concentration
of 15 ug/1, the approximate TCE mass removal rate is 4.3 Ibs/yr. The stripper effectively treats
the TCE in water to below the effluent discharge standard of 3 ug/1 prior to discharge to Hog
Run Creek.
Off-gas from the stripper is heated and treated with VGAC, which is changed every other year.
Air sampling on the VGAC is conducted quarterly using 7 canisters (GAC influent, GAC
effluent, field blank, upwind, downwind, and at two residences). This requires two people for
four hours per event. Analysis is performed by EPA contract lab (no charge to site). Given the
low mass removed by the system (4.3 Ibs/yr) the daily discharge of TCE to the air would be
minimal even with carbon breakthrough.
Surface water in Hog Run Creek is no longer sampled because of the very low contaminant
concentrations in ground water (historically very low detections of VOCs in surface water were
observed, but that was when ground water concentrations were much higher).
The source of the TCE impacts west of Hog Run Creek (i.e., associated with the Croydon TCE
site) has never been determined, despite attempts to do so as described in the OU2 ROD.
Air stripper influent (and all other process monitoring) is analyzed quarterly. A sampling
method is used where three different samples are taken 30 minutes apart, and each is analyzed.
Although the site does not pay for the analyses (performed by the contract lab), the evaluation
team noted during the evaluation meeting that analyzing three samples seems unnecessary from a
technical standpoint, and given the consistency of past results, requesting a variance from any
such regulation should be considered.
The planned turnover date to PADEP is November 2005.
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A formal capture zone analysis has not been performed. However, given the lack of potential
receptors, and the fact that such low TCE concentrations in ground water would not be expected
to negatively impact the creek (where it discharges), some gaps in capture would likely not be a
great concern at this site.
The treatment plant is located on Rohm & Haas property, and the access agreement reportedly
expired in 2004. This needs to be extended if the State plans on continuing operation. Also,
any new wells near the creek that might be installed to better monitor conditions if the system is
shut down would require an easement from Rohm and Haas.
Although concentrations are declining and are quite low, current cleanup standards in the ROD will not
likely be met for many years. A primary issue at this site in the future will be whether or not P&T
should continue. Considerations pertinent to this issue include the following: (1) the current cleanup
levels are below MCLs, and ultimately changing these standards to MCLs to be consistent with other
RODs is likely appropriate and should be considered; (2) although dilution and dispersion are occurring,
breakdown products are not observed (although that may be due to the low TCE concentrations and
therefore low concentrations of breakdown products) and a strong argument for MNA as a result of
degradation cannot easily be made,; (3) concentrations of TCE are decreasing in key monitoring wells
and mass continues to be removed from the affected aquifer; and (4) if at some point in the future trends
of contaminant concentration and mass removal become asymptotic and it becomes apparent that
ARARs will not be met, a TI waiver could be pursued.
2.0 RECOMMENDATIONS TO IMPROVE SYSTEM PROTECTIVENESS
2.1 WORK WITH COUNTY TO INSTITUTE INSTITUTIONAL CONTROLS
Although no potential receptors are apparent, the ROD indicates that institutional controls
should be implemented as part of the remedy. EPA and PADEP should meet with the
County to determine what (if anything) needs to be done to make sure no new wells can be
drilled in areas potentially impacted by the site. EPA efforts for coordinating and/or
participating in these activities might cost $15,000 assuming contractor support for meetings
and other support tasks are required.
2.2 EXTEND ACCESS AGREEMENT WITH ROHM AND HAAS
If not already done, the access agreement with Rohm and Haas should be extended to allow
for continued operation of the P&T system, monitoring of existing wells on Rohm and Haas
property, and installation plus continued monitoring of potential new wells on Rohm and
Haas property. The cost for these efforts cannot easily be quantified as part of this
evaluation.
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3.0 RECOMMENDATIONS TO REDUCE SYSTEM COST
3.1 REDUCE PROCESS MONITORING
To the extent P&T continues, the practice of taking 3 samples 30 minutes apart for each
event is technically not justified, based on the consistency of historical data. It is
recommended that a variance be requested from whatever requirement is the basis for such
sampling. The cost savings for the site are negligible given that analysis is performed by
contract lab, but the current practice causes unnecessary effort with respect to sampling,
analysis at the lab, and reporting.
To the extent that P&T continues, it is recommended that air monitoring for the VGAC
effluent be discontinued, or at most conducted once every other year (i.e., between
changeouts to verify breakthrough has not occurred). Given the low TCE concentrations that
result in very little mass removed by the system (4.3 Ibs/yr = 0.01 Ibs/day) it can be easily
demonstrated that no impacts will occur to receptors even if there is VGAC breakthrough.
Currently, VGAC is changed every other year, and cost to do those changes is low (estimated
at approximately $2,000/yr). Therefore, it is recommended that VGAC changeouts continue
to occur at the same frequency but monitoring be discontinued (or at most occur once every
two years, between changeouts). Assuming this sampling is completely eliminated,
estimated savings in labor is approximately $2,000/yr (4 hrs x 2 people x $60/hr x 4 events).
Again, the laboratory analysis savings will not be realized by the site, but unnecessary effort
with respect analysis at the lab, and reporting, will also be avoided.
4.0 RECOMMENDATIONS FOR TECHNICAL IMPROVEMENT
None. If P&T is expected to continue for a long period of time, the site team could perhaps
consider an evaluation to modify pumping rates to target the most impacted areas. However, this
effort is likely not merited if the system will only operate for a relatively short period in the
future. Given the current low TCE concentrations in ground water, and the potential for current
(or potentially modified) ARAR's to be met within several (i.e., two to three) years, such an
evaluation to modify pumping rates should only be performed if the site team determines it to be
likely that the system will continue to operate for many years.
5.0 RECOMMENDATIONS To SPEED SITE CLOSEOUT
5.1 DEFER P&T SYSTEM EXIT STRATEGY TO AFTER TRANSFER OF THE SITE TO THE STATE
The TCE concentrations at the site are relatively low (a maximum of approximately 16 ug/L
relative to the MCL of 5 ug/L), and concentrations continue to decrease. Although this
represents significant progress toward aquifer restoration, it also means that the P&T system
is having a diminishing effect on removing contaminant mass and progressing toward aquifer
restoration. The site team should begin to consider the point at which P&T will provide no
additional benefit to the natural processes of dilution and dispersion (and possibly
degradation) that are occurring. With P&T operation, TCE concentrations may continue to
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decline or they may become asymptotic, indicating the impracticability of the P&T system to
meet the current (or potentially modified) cleanup standard. It is unlikely that any decision
to shut down the P&T system will be made before the site is transferred to the State. As a
result, the evaluation team suggests that an exit strategy for the P&T system be deferred until
after the site is transferred to the State in November 2005. The State can then work with
EPA to consider the concentration trends, determine the effect the P&T system has on
reaching the cleanup standard, develop an appropriate cleanup standard, and determine an
appropriate point to discontinue P&T. If the State (in concert with EPA) determines that
P&T can be appropriately discontinued before the cleanup standard is met (perhaps in
association with a technical impracticability determination), the costs for annual O&M will
likely decrease to approximately $50,000 or less, which would result in a savings of
approximately $80,000 per year compared to continuing to operate the P&T system.
PRIORITIZATION AND SEQUENCING OF RECOMMENDATIONS
All of the recommendations can be implemented within the next several months, and should be
substantially completed within FY05.
OTHER ACTION ITEMS
No other action items are provided.
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Cost Summary Table
Recommendation
2.1 Work With County To
Institute Institutional Controls
2.2 Extend Access Agreement
With Rohm And Haas
3.1 Reduce Process Monitoring
5.1 Defer P&T System Exit
Strategy to After Transfer of the
Site to the State
Reason
Effectiveness
Effectiveness
Cost Reduction
Site Closeout
Estimated Additional
Capital Costs
($)
$15,000
Not quantified
$0
Not Quantified
Estimated Change in
Annual Costs
($/yr)
$0
Not quantified
($2,000)
($80,000)*
Costs in parentheses imply cost reductions.
* Potential estimated annual savings that might be realized if P&T system is ultimately shut down.
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