CY-05-243, Transmittal of the Phase 2 Hydrogeologic Investigation Work Plan, Task 3 Deliverable - Groundwater Modeling Report: Difference between revisions

From kanterella
Jump to navigation Jump to search
(Created page by program invented by StriderTol)
 
(Created page by program invented by StriderTol)
 
Line 16: Line 16:


=Text=
=Text=
{{#Wiki_filter:CONNECTICUT YANKEE ATOMIC POWER COMPANY HADDAM NECK PLANT 362 INJUN HOLLOW ROAD
{{#Wiki_filter:CONNECTICUT           YANKEE     ATOMIC POWER COMPANY HADDAM NECK PLANT 362 INJUN HOLLOW ROAD
* EAST HAMPTON, CT 06424-3099 DEC 1 5 2005 CY-05-243 Mr. Peter Hill, LEP Bureau of Waste Management Connecticut Department of Environmental Protection 79 Elm Street Hartford, CT 06106-5127 Haddam Neck Plant Transmittal of the Phase 2 Hydrogeologic Investigation Work PlanTask 3 Deliverable  
* EAST HAMPTON, CT 06424-3099 DEC 1 5 2005 CY-05-243 Mr. Peter Hill, LEP Bureau of Waste Management Connecticut Department of Environmental Protection 79 Elm Street Hartford, CT 06106-5127 Haddam Neck Plant Transmittal of the Phase 2 Hydrogeologic Investigation Work PlanTask 3 Deliverable - Groundwater Modeling Report
-Groundwater Modeling Report  


==Dear Mr. Hill:==
==Dear Mr. Hill:==
Connecticut Yankee Atomic Power Company (CYAPCO) hereby submits the Phase 2 Hydrogeologic Investigation Work Plan (Work Plan) Task 3 deliverable.
Connecticut Yankee Atomic Power Company (CYAPCO) hereby submits the Phase 2 Hydrogeologic Investigation Work Plan (Work Plan) Task 3 deliverable.
Specifically, CYAPCO has developed a suite of groundwater models to support the decommissioning of CYAPCO's Haddam Neck Plant (HNP) and is hereby providing the Groundwater Modeling Report (Attachment 2). Development of a numerical simulation tool for the HNP was identified as a requirement under the Phase 2 Hydrogeologic Investigation Work Plan. The Work Plan was approved by the Connecticut Department of Environmental Protection (CT DEP) on May 10, 20021.The Work Plan consists of three tasks; 1) Task 1-Existing Data Evaluation, 2)Additional Site Characterization, and 3) Evaluation of Fate and Transport Modeling.CYAPCO submitted the Phase 2 Work Plan Task 1 and Task 2 deliverables on April 19, 20042, and November 29, 20043, respectively.
Specifically, CYAPCO has developed a suite of groundwater models to support the decommissioning of CYAPCO's Haddam Neck Plant (HNP) and is hereby providing the Groundwater Modeling Report (Attachment 2). Development of a numerical simulation tool for the HNP was identified as a requirement under the Phase 2 Hydrogeologic Investigation Work Plan. The Work Plan was approved by the Connecticut Department of Environmental Protection (CT DEP) on May 10, 20021.
1 E. B. Patton (CT DEP) letter to K. Heider (CYAPCO), "Phase 2 Hydrologic Investigation Work Plan, Connecticut Yankee Atomic Power Company", dated May 10, 2002.2 G. P. van Noordennen (CYAPCO) letter to P. Hill (CT DEP), "Phase 2 Hydrogeological Investigation Work Plan- Task 1 Deliverables", dated April 19, 2004.3 G. P. van Noordennen (CYAPCO) letter to P. Hill CT DEP), "Transmittal of Task 2 Supplemental Characterization Report", dated November 29, 2004.1ESO Mr. Peter Hill CY-05-243IPage 2 The groundwater modeling activity is described generically under specifications of Task 3 of the Work Plan. The primary use of the simulation tool is to identify potential groundwater flow paths that can be used to assess groundwater monitoring needs (e.g., monitoring well locations, well depths and screened interval depths).Although the model has the capability to simulate fate and transport of specific constituents of concern, this capability is deemed to be less useful than the flow simulation due to the "mature" state of the groundwater contamination conditions at the HNP and on-going removal of primary and secondary sources of contamination.
The Work Plan consists of three tasks; 1) Task 1-Existing Data Evaluation, 2)
A "mature" groundwater contamination condition is indicated by generally stable or diminishing contaminant concentrations in groundwater and apparent cessation of release of contaminants from identified source areas (or removal of those sources).The modeling activity for the HNP has, therefore, focused most intensively on simulation of groundwater flow pathways, rather than reactive transport simulation of migration of specific contaminants along those pathways Attachment 1 provides a matrix delineating the completed activities against the required activities under the Work Plan. Based on Attachment 1 and this submittal along with the submittals dated April 19, 2004 and November 29, 2004, CYAPCO concludes that all the activities included in the scope of the Work Plan, except the activity related to the investigation opposite the Connecticut River from the HNP site, are completed.
Additional Site Characterization, and 3) Evaluation of Fate and Transport Modeling.
If you have any questions regarding this submittal, please call me at (860) 267-3938.Sincerely, 49&yW, 19-1 0Z^5 Gerard P. van Noordennen Date Regulatory Affairs Manager  
CYAPCO submitted the Phase 2 Work Plan Task 1 and Task 2 deliverables on April 19, 20042, and November 29, 20043, respectively.
1 E. B. Patton (CT DEP) letter to K. Heider (CYAPCO), "Phase 2 Hydrologic Investigation Work Plan, Connecticut Yankee Atomic Power Company", dated May 10, 2002.
2 G. P. van Noordennen (CYAPCO) letter to P. Hill (CT DEP), "Phase 2 Hydrogeological Investigation Work Plan- Task 1 Deliverables", dated April 19, 2004.
3 G. P. van Noordennen (CYAPCO) letter to P. Hill CT DEP), "Transmittal of Task 2 Supplemental Characterization Report", dated November 29, 2004.
1ESO
 
Mr. Peter Hill CY-05-243IPage 2 The groundwater modeling activity is described generically under specifications of Task 3 of the Work Plan. The primary use of the simulation tool is to identify potential groundwater flow paths that can be used to assess groundwater monitoring needs (e.g., monitoring well locations, well depths and screened interval depths).
Although the model has the capability to simulate fate and transport of specific constituents of concern, this capability is deemed to be less useful than the flow simulation due to the "mature" state of the groundwater contamination conditions at the HNP and on-going removal of primary and secondary sources of contamination.
A "mature" groundwater contamination condition is indicated by generally stable or diminishing contaminant concentrations in groundwater and apparent cessation of release of contaminants from identified source areas (or removal of those sources).
The modeling activity for the HNP has, therefore, focused most intensively on simulation of groundwater flow pathways, rather than reactive transport simulation of migration of specific contaminants along those pathways provides a matrix delineating the completed activities against the required activities under the Work Plan. Based on Attachment 1 and this submittal along with the submittals dated April 19, 2004 and November 29, 2004, CYAPCO concludes that all the activities included in the scope of the Work Plan, except the activity related to the investigation opposite the Connecticut River from the HNP site, are completed.
If you have any questions regarding this submittal, please call me at (860) 267-3938.
Sincerely, 49&yW,                             19-1 0Z^5 Gerard P.van Noordennen               Date Regulatory Affairs Manager


==Attachment:==
==Attachment:==
Task 3 Groundwater Modeling Report, November 2005 cc:    Mr. M. Firsick, CTDEP, Bureau of Radiation Protection Mr. G. Ginsberg, CTDPH Ms. M. Miller, USNRC Region 1 NRC Document Control Desk Mr. T. Smith, USNRC Headquakters Mr. J. Perez, USEPA Region 1 Mr. M. Rosenstein, USEPA Region I
CY-05-243 Attachment 1 Haddam Neck Plant A Review of the Phase 2 Work Plan to Identify Tasks Vs Task Completed December 2005
CY-05-243 ATIACHMENT 1 A REVIEW OF THE "PHASE 2 WORK PLAN" TO IDENTIFY TASKS VS TASK-COMPLETED AS PER THE SCOPE OF THE DOCUMENT To ensure CYAPCO is conducting the site characterization and investigations of the Haddam Neck Plant as defined in the Phase 2 Hydrogeologic Investigation Work Plan, March 2001, Malcolm Pirnie, each item of the work plan was reviewed as described below:
Variations How and/or where Task          Activity and scope                      Objective                        How performed                from work  is the performance plan        documented?
Compile well and geologic        To develop the understanding        Obtained and reviewed publicly            -NA-    Task 1 Summary Report data for domestic wells within  of local hydrogeologic              available well logs, identified mile north-south and one-half    conditions                          locations, and assessed conditions mile east-west of HNP                                                described in logs.
Compile and review existing      To determine potential              Obtained river stage records and          -NA-    Task 1 Summary Report tidal studies                    influences of the tidal            other applicable information.
fluctuations on groundwater and contaminant tansport Compile and review onsite        To determine the seasonal and      An onsite weather station provides        -NA-    Task 1 Summary Report and regional precip. Data.      single incident effects of rainfall site specific rainfall data, as do the (collected for a minimum of      and runoff on the groundwater      Meriden, CT, and surrounding one year and compared to the    and transport mechanisms.          communities. Data were assessed Bridgeport station for                                              and compared to Bridgeport records.
sinilarity)
Review construction records      Determine blasting effects, i.e. As built diagrams, photographs of        -NA-    Task 1 Summary Report and blasting records for        the depth of fracture              the plant construction evolutions and information on potential blast  penetration resulting from the      shift records were reviewed and fractured bedrock                blast(s) and the resultant effect  assessed to determine if any effects on the bedrock groundwater          are obvious or need to be addressed flow and transport                  in the flow regimens for the site.
Review geologic and            To identify geologic structures      Early construction diagrams,              -NA-    Task 1 Summary Report hydrogeologic data associated    and potential impacts of            geologic records and survey data with facility siting and        structures and facilities          were reviewed along with any and construction                    associated with the plant.          all sample data for the site prior to excavation and construction
CY-05-243 ATTACHMENT 1 A REVIEW OF THE "PHASE 2 WORK PLAN" TO IDENTIFY TASKS VS TASK-COMPLETED AS PER THE SCOPE OF THE DOCUMENT Variations  How and/or where Task    Activity and scope                        Objective                        How performed                  from work  is the performance plan        documented?
Present results of geologic      To evaluate the geologic            Geologic outcrop and structures          -NA-      Task 1 Summary Report mapping of outcrops to the        framework for a stable siting of    were mapped in the immediate east of the plant, and a review  a nuclear plant, and verify that    vicinity of the HNP and compared to of the "overburden" and          platform was not degraded          the original maps and data to bedrock geology including        during construction in addition    develop an understanding of the pre- and post-construction        to developing a basic geologic      bedrock surface changes due to plant bedrock contour maps              footprint.                          construction. Bedrock surface maps were prepared Analyze the potential            To assess the consolidated and      Maps, boreholes, design and              -NA-      Task 1 Summary Report preferential pathways for        unconsolidated geologic            construction drawings and groundwater flow                  deposits and their relationship    groundwater monitoring data to structures and evaluate          revealed where the building groundwater flow and identify      supports are constructed directly potential preferential flow        onto bedrock, foundations extend pathways.                          well into the unconsolidated soils, and the density of those structures will provide an impediment to groundwater flow and transport Groundwater flow in bedrock was established as a preferential pathway for flow.
Present the locations of          Identify existing boring            Locate and verify the positions of,      -NA-      Task 1 Summary Report borings and existing              locations and uses then            total depth, and water table elevation monitoring wells,                incorporate the data and results    in existing monitoring wells. Assess hydrogeologic data and SOC        into structural, stratigraphic,    existing cross sections.
concentrations obtained          and hydrogeologic understanding, Develop conceptual site model    The objective is to collate, digest Integrate existing information            -NA-    Preliminary CSM in Task 1 and condense the acquired data into (hydrogeological, contamrinant                    Summary Report formats from which a conceptual    distribution, geochemistry) into                  Revised CSM in model of the flow structure,        conceptual site model and revise as              Hydrogeologic Conceptual Site transport mechanisms, plume        new information is developed.                    Modelfor tihe HaddainNeck definition and potential source                                                      Plant,Haddarn Neck, areas can be generated                                                                Connecticut June 2005
CY-05-243 ATTACHMENT 1 A REVIEW OF THE "PHASE 2 WORK PLAN" TO IDENTIFY TASKS VS TASK-COMPLETED AS PER THE SCOPE OF THE DOCUMENT Variations          How and/or where Task    Activity and scope                      Objective                        How performed                  from work          is the performance plan              documented?
2  Simultaneous collection of      To determine the influence of tidal A network of 30 data-logging                  -NA-        Task 1 Summary Report surface elevation data in the  effects on the groundwater          pressure transducers was installed in                      Task 2 Supplemental river, canal and adjacent                                          monitoring wells on-site and in the                        Characterization Report monitoring wells.                                                  Connecticut River to record water                          and subsequent Semi-elevations                                                  Annual Groundwater Monitoring Reports Overburden and bedrock          To supplement the current          72-hour Aquifer pumping test          25 bedrock borings,  Task 2 Supplemental hydrogeological                understanding of the geology and    performed in the unconsolidated      ranging from 10 feet  Characterization Report characterization through        hydrogeology at the HNP.            formation.                            to 50 feet in depth  and subsequent Semi-drillin& soil sampling rock                                        Packer testing, geophysical logging,  were investigated in  Annual Groundwater coring, downhole logging                                            camera logging. and hydrophysical    the former tank      Monitoring Reports (geophysics), hydraulic                                            logging of bedrock boreholes.        farm area. These conductivity, overburden                                            Examination of rock cores collected  borings were used testing. transmissivity and                                        from borings.                        to characterize bedrock interconnectivity                                          Transducer network records were      bedrock in lieu of evaluated to identify hydraulic      the initially-responses to pumping and packer      planned boring testing.                              103B. An additional monitoring well has been installed in the general vicinity identified for 103B to monitor water quality near the tank farm source area Installation, sampling and      To verify the background levels in  Monitoring wells MW-118A, MW-                  -NA-            Task 2 Supplemental radiological analyses of        groundwater, and establish          119, MW-120, MW-121A, MW-122,                                Characterization Report groundwater from onsite        naturally occurring radiological    MW-123, MW-124, MW-125, MW-                                    and subsequent Semi-solitary and clustered          substances                          130, MW-131, MW-132, MW-133,                                    Annual Groundwater monitoring wells and the                                            MW-134, MW-135 have been                                        Monitoring Reports residential                                                        installed. Wells MW-122D and MW-former Schmidt residential                                          106D were replaced to correct water supply                                                        defective seals. Wells destroyed during demolition in the industrial area are being replaced as demolition is completed.


Task 3 Groundwater Modeling Report, November 2005 cc: Mr. M. Firsick, CTDEP, Bureau of Radiation Protection Mr. G. Ginsberg, CTDPH Ms. M. Miller, USNRC Region 1 NRC Document Control Desk Mr. T. Smith, USNRC Headquakters Mr. J. Perez, USEPA Region 1 Mr. M. Rosenstein, USEPA Region I CY-05-243 Attachment 1 Haddam Neck Plant A Review of the Phase 2 Work Plan to Identify Tasks Vs Task Completed December 2005 CY-05-243 ATIACHMENT 1 A REVIEW OF THE "PHASE 2 WORK PLAN" TO IDENTIFY TASKS VS TASK-COMPLETED AS PER THE SCOPE OF THE DOCUMENT To ensure CYAPCO is conducting the site characterization and investigations of the Haddam Neck Plant as defined in the Phase 2 Hydrogeologic Investigation Work Plan, March 2001, Malcolm Pirnie, each item of the work plan was reviewed as described below: Variations How and/or where Task Activity and scope Objective How performed from work is the performance plan documented?
CY-05-243 ATTACHMENT 1 A REVIEW OF THE "PHASE 2 WORK PLAN" TO IDENTIFY TASKS VS TASK-COMPLETED AS PER THE SCOPE OF THE DOCUMENT Variations How and/or where Task   Activity and scope                       Objective                         How performed                 from work   is the performance plan         documented?
Compile well and geologic To develop the understanding Obtained and reviewed publicly -NA- Task 1 Summary Report data for domestic wells within of local hydrogeologic available well logs, identified mile north-south and one-half conditions locations, and assessed conditions mile east-west of HNP described in logs.Compile and review existing To determine potential Obtained river stage records and -NA- Task 1 Summary Report tidal studies influences of the tidal other applicable information.
Radiological groundwater         To build a well across the river     The well design has been completed       -NA-   To be documented in quality investigation opposite   from the HNP and evaluate the       and the easements are in process for             subsequent Semi-Annual the river from the site         groundwater for possible man-       the drilling location. Data from the             Groundwater Monitoring made radionuclides                   deep bedrock "Westbay" wells have                 Reports been evaluated and have been incorporated into the drilling and sampling plan for these wells.
fluctuations on groundwater and contaminant tansport Compile and review onsite To determine the seasonal and An onsite weather station provides -NA- Task 1 Summary Report and regional precip. Data. single incident effects of rainfall site specific rainfall data, as do the (collected for a minimum of and runoff on the groundwater Meriden, CT, and surrounding one year and compared to the and transport mechanisms.
3   Evaluation of fate and           To constiuct a model to forecast the The groundwater addresses the             -NA-   Groundwater Modeling transport modeling               nature and extent of potential or   hydrologic parameters, completeness               Report (December 2005) actual plumes and concentrations of of the data set, plume characteristics those plumes at UNP                 and future movement. The model is constructed using MODFLOW.
communities.
Landfill area groundwater       Downgradient monitoring of the       Use the existing monitoring wells for     -NA-   Semi-Annual Groundwater monitoring                       landfill area                       sampling groundwater, quarterly.                 Monitoring Reports Groundwater sampling and         Obtain quarterly samples from       Sampling continues on a quarterly         -NA-   Serni-Annual Groundwater analyses                         specified wells and analyze for H3, basis and is presented in semi-annual             Monitoring Reports B, alpha and gamma emitting         reports nuclides, and Sr-90 Groundwater monitoring           Compile a record of the monitoring   Sample and assimilate the analytical     -NA-   Semi-Annual Groundwater reports                         well water level activities,         results then incorporate them into               Monitoring Reports barometric and precipitation effects groundwater and contaminant on groundwater, sampling and         plume trend maps while using the analytical results, and plume       corrected water level measurements modifications due to new             and effects from natural occurring information.                         recharge. The report will inulude summary tables of the sampling and field notes, discussion of the results and recommendations for revisions to the plan.}}
Data were assessed Bridgeport station for and compared to Bridgeport records.sinilarity)
Review construction records Determine blasting effects, i.e. As built diagrams, photographs of -NA- Task 1 Summary Report and blasting records for the depth of fracture the plant construction evolutions and information on potential blast penetration resulting from the shift records were reviewed and fractured bedrock blast(s) and the resultant effect assessed to determine if any effects on the bedrock groundwater are obvious or need to be addressed flow and transport in the flow regimens for the site.Review geologic and To identify geologic structures Early construction diagrams, -NA- Task 1 Summary Report hydrogeologic data associated and potential impacts of geologic records and survey data with facility siting and structures and facilities were reviewed along with any and construction associated with the plant. all sample data for the site prior to excavation and construction CY-05-243 ATTACHMENT 1 A REVIEW OF THE "PHASE 2 WORK PLAN" TO IDENTIFY TASKS VS TASK-COMPLETED AS PER THE SCOPE OF THE DOCUMENT Variations How and/or where Task Activity and scope Objective How performed from work is the performance plan documented?
Present results of geologic To evaluate the geologic Geologic outcrop and structures -NA- Task 1 Summary Report mapping of outcrops to the framework for a stable siting of were mapped in the immediate east of the plant, and a review a nuclear plant, and verify that vicinity of the HNP and compared to of the "overburden" and platform was not degraded the original maps and data to bedrock geology including during construction in addition develop an understanding of the pre- and post-construction to developing a basic geologic bedrock surface changes due to plant bedrock contour maps footprint.
construction.
Bedrock surface maps were prepared Analyze the potential To assess the consolidated and Maps, boreholes, design and -NA- Task 1 Summary Report preferential pathways for unconsolidated geologic construction drawings and groundwater flow deposits and their relationship groundwater monitoring data to structures and evaluate revealed where the building groundwater flow and identify supports are constructed directly potential preferential flow onto bedrock, foundations extend pathways.
well into the unconsolidated soils, and the density of those structures will provide an impediment to groundwater flow and transport Groundwater flow in bedrock was established as a preferential pathway for flow.Present the locations of Identify existing boring Locate and verify the positions of, -NA- Task 1 Summary Report borings and existing locations and uses then total depth, and water table elevation monitoring wells, incorporate the data and results in existing monitoring wells. Assess hydrogeologic data and SOC into structural, stratigraphic, existing cross sections.concentrations obtained and hydrogeologic understanding, Develop conceptual site model The objective is to collate, digest Integrate existing information -NA- Preliminary CSM in Task 1 and condense the acquired data into (hydrogeological, contamrinant Summary Report formats from which a conceptual distribution, geochemistry) into Revised CSM in model of the flow structure, conceptual site model and revise as Hydrogeologic Conceptual Site transport mechanisms, plume new information is developed.
Modelfor tihe Haddain Neck definition and potential source Plant, Haddarn Neck, areas can be generated Connecticut June 2005 CY-05-243 ATTACHMENT 1 A REVIEW OF THE "PHASE 2 WORK PLAN" TO IDENTIFY TASKS VS TASK-COMPLETED AS PER THE SCOPE OF THE DOCUMENT Variations How and/or where Task Activity and scope Objective How performed from work is the performance plan documented?
2 Simultaneous collection of To determine the influence of tidal A network of 30 data-logging -NA- Task 1 Summary Report surface elevation data in the effects on the groundwater pressure transducers was installed in Task 2 Supplemental river, canal and adjacent monitoring wells on-site and in the Characterization Report monitoring wells. Connecticut River to record water and subsequent Semi-elevations Annual Groundwater Monitoring Reports Overburden and bedrock To supplement the current 72-hour Aquifer pumping test 25 bedrock borings, Task 2 Supplemental hydrogeological understanding of the geology and performed in the unconsolidated ranging from 10 feet Characterization Report characterization through hydrogeology at the HNP. formation.
to 50 feet in depth and subsequent Semi-drillin& soil sampling rock Packer testing, geophysical logging, were investigated in Annual Groundwater coring, downhole logging camera logging. and hydrophysical the former tank Monitoring Reports (geophysics), hydraulic logging of bedrock boreholes.
farm area. These conductivity, overburden Examination of rock cores collected borings were used testing. transmissivity and from borings. to characterize bedrock interconnectivity Transducer network records were bedrock in lieu of evaluated to identify hydraulic the initially-responses to pumping and packer planned boring testing. 103B. An additional monitoring well has been installed in the general vicinity identified for 103B to monitor water quality near the tank farm source area Installation, sampling and To verify the background levels in Monitoring wells MW-118A, MW- -NA- Task 2 Supplemental radiological analyses of groundwater, and establish 119, MW-120, MW-121A, MW-122, Characterization Report groundwater from onsite naturally occurring radiological MW-123, MW-124, MW-125, MW- and subsequent Semi-solitary and clustered substances 130, MW-131, MW-132, MW-133, Annual Groundwater monitoring wells and the MW-134, MW-135 have been Monitoring Reports residential installed.
Wells MW-122D and MW-former Schmidt residential 106D were replaced to correct water supply defective seals. Wells destroyed during demolition in the industrial area are being replaced as demolition is completed.
CY-05-243 ATTACHMENT 1 A REVIEW OF THE "PHASE 2 WORK PLAN" TO IDENTIFY TASKS VS TASK-COMPLETED AS PER THE SCOPE OF THE DOCUMENT Variations How and/or where Task Activity and scope Objective How performed from work is the performance plan documented?
Radiological groundwater To build a well across the river The well design has been completed -NA- To be documented in quality investigation opposite from the HNP and evaluate the and the easements are in process for subsequent Semi-Annual the river from the site groundwater for possible man- the drilling location.
Data from the Groundwater Monitoring made radionuclides deep bedrock "Westbay" wells have Reports been evaluated and have been incorporated into the drilling and sampling plan for these wells.3 Evaluation of fate and To constiuct a model to forecast the The groundwater addresses the -NA- Groundwater Modeling transport modeling nature and extent of potential or hydrologic parameters, completeness Report (December 2005)actual plumes and concentrations of of the data set, plume characteristics those plumes at UNP and future movement.
The model is constructed using MODFLOW.Landfill area groundwater Downgradient monitoring of the Use the existing monitoring wells for -NA- Semi-Annual Groundwater monitoring landfill area sampling groundwater, quarterly.
Monitoring Reports Groundwater sampling and Obtain quarterly samples from Sampling continues on a quarterly -NA- Serni-Annual Groundwater analyses specified wells and analyze for H3, basis and is presented in semi-annual Monitoring Reports B, alpha and gamma emitting reports nuclides, and Sr-90 Groundwater monitoring Compile a record of the monitoring Sample and assimilate the analytical -NA- Semi-Annual Groundwater reports well water level activities, results then incorporate them into Monitoring Reports barometric and precipitation effects groundwater and contaminant on groundwater, sampling and plume trend maps while using the analytical results, and plume corrected water level measurements modifications due to new and effects from natural occurring information.
recharge.
The report will inulude summary tables of the sampling and field notes, discussion of the results and recommendations for revisions to the plan.}}

Latest revision as of 00:39, 24 November 2019

Transmittal of the Phase 2 Hydrogeologic Investigation Work Plan, Task 3 Deliverable - Groundwater Modeling Report
ML053560275
Person / Time
Site: Haddam Neck File:Connecticut Yankee Atomic Power Co icon.png
Issue date: 12/15/2005
From: Gerard van Noordennen
Connecticut Yankee Atomic Power Co
To: Hill P
NRC/FSME, State of CT, Dept of Environmental Protection
References
CY-05-243
Download: ML053560275 (7)
v • d • e


Text

CONNECTICUT YANKEE ATOMIC POWER COMPANY HADDAM NECK PLANT 362 INJUN HOLLOW ROAD

  • EAST HAMPTON, CT 06424-3099 DEC 1 5 2005 CY-05-243 Mr. Peter Hill, LEP Bureau of Waste Management Connecticut Department of Environmental Protection 79 Elm Street Hartford, CT 06106-5127 Haddam Neck Plant Transmittal of the Phase 2 Hydrogeologic Investigation Work PlanTask 3 Deliverable - Groundwater Modeling Report

Dear Mr. Hill:

Connecticut Yankee Atomic Power Company (CYAPCO) hereby submits the Phase 2 Hydrogeologic Investigation Work Plan (Work Plan) Task 3 deliverable.

Specifically, CYAPCO has developed a suite of groundwater models to support the decommissioning of CYAPCO's Haddam Neck Plant (HNP) and is hereby providing the Groundwater Modeling Report (Attachment 2). Development of a numerical simulation tool for the HNP was identified as a requirement under the Phase 2 Hydrogeologic Investigation Work Plan. The Work Plan was approved by the Connecticut Department of Environmental Protection (CT DEP) on May 10, 20021.

The Work Plan consists of three tasks; 1) Task 1-Existing Data Evaluation, 2)

Additional Site Characterization, and 3) Evaluation of Fate and Transport Modeling.

CYAPCO submitted the Phase 2 Work Plan Task 1 and Task 2 deliverables on April 19, 20042, and November 29, 20043, respectively.

1 E. B. Patton (CT DEP) letter to K. Heider (CYAPCO), "Phase 2 Hydrologic Investigation Work Plan, Connecticut Yankee Atomic Power Company", dated May 10, 2002.

2 G. P. van Noordennen (CYAPCO) letter to P. Hill (CT DEP), "Phase 2 Hydrogeological Investigation Work Plan- Task 1 Deliverables", dated April 19, 2004.

3 G. P. van Noordennen (CYAPCO) letter to P. Hill CT DEP), "Transmittal of Task 2 Supplemental Characterization Report", dated November 29, 2004.

1ESO

Mr. Peter Hill CY-05-243IPage 2 The groundwater modeling activity is described generically under specifications of Task 3 of the Work Plan. The primary use of the simulation tool is to identify potential groundwater flow paths that can be used to assess groundwater monitoring needs (e.g., monitoring well locations, well depths and screened interval depths).

Although the model has the capability to simulate fate and transport of specific constituents of concern, this capability is deemed to be less useful than the flow simulation due to the "mature" state of the groundwater contamination conditions at the HNP and on-going removal of primary and secondary sources of contamination.

A "mature" groundwater contamination condition is indicated by generally stable or diminishing contaminant concentrations in groundwater and apparent cessation of release of contaminants from identified source areas (or removal of those sources).

The modeling activity for the HNP has, therefore, focused most intensively on simulation of groundwater flow pathways, rather than reactive transport simulation of migration of specific contaminants along those pathways provides a matrix delineating the completed activities against the required activities under the Work Plan. Based on Attachment 1 and this submittal along with the submittals dated April 19, 2004 and November 29, 2004, CYAPCO concludes that all the activities included in the scope of the Work Plan, except the activity related to the investigation opposite the Connecticut River from the HNP site, are completed.

If you have any questions regarding this submittal, please call me at (860) 267-3938.

Sincerely, 49&yW, 19-1 0Z^5 Gerard P.van Noordennen Date Regulatory Affairs Manager

Attachment:

Task 3 Groundwater Modeling Report, November 2005 cc: Mr. M. Firsick, CTDEP, Bureau of Radiation Protection Mr. G. Ginsberg, CTDPH Ms. M. Miller, USNRC Region 1 NRC Document Control Desk Mr. T. Smith, USNRC Headquakters Mr. J. Perez, USEPA Region 1 Mr. M. Rosenstein, USEPA Region I

CY-05-243 Attachment 1 Haddam Neck Plant A Review of the Phase 2 Work Plan to Identify Tasks Vs Task Completed December 2005

CY-05-243 ATIACHMENT 1 A REVIEW OF THE "PHASE 2 WORK PLAN" TO IDENTIFY TASKS VS TASK-COMPLETED AS PER THE SCOPE OF THE DOCUMENT To ensure CYAPCO is conducting the site characterization and investigations of the Haddam Neck Plant as defined in the Phase 2 Hydrogeologic Investigation Work Plan, March 2001, Malcolm Pirnie, each item of the work plan was reviewed as described below:

Variations How and/or where Task Activity and scope Objective How performed from work is the performance plan documented?

Compile well and geologic To develop the understanding Obtained and reviewed publicly -NA- Task 1 Summary Report data for domestic wells within of local hydrogeologic available well logs, identified mile north-south and one-half conditions locations, and assessed conditions mile east-west of HNP described in logs.

Compile and review existing To determine potential Obtained river stage records and -NA- Task 1 Summary Report tidal studies influences of the tidal other applicable information.

fluctuations on groundwater and contaminant tansport Compile and review onsite To determine the seasonal and An onsite weather station provides -NA- Task 1 Summary Report and regional precip. Data. single incident effects of rainfall site specific rainfall data, as do the (collected for a minimum of and runoff on the groundwater Meriden, CT, and surrounding one year and compared to the and transport mechanisms. communities. Data were assessed Bridgeport station for and compared to Bridgeport records.

sinilarity)

Review construction records Determine blasting effects, i.e. As built diagrams, photographs of -NA- Task 1 Summary Report and blasting records for the depth of fracture the plant construction evolutions and information on potential blast penetration resulting from the shift records were reviewed and fractured bedrock blast(s) and the resultant effect assessed to determine if any effects on the bedrock groundwater are obvious or need to be addressed flow and transport in the flow regimens for the site.

Review geologic and To identify geologic structures Early construction diagrams, -NA- Task 1 Summary Report hydrogeologic data associated and potential impacts of geologic records and survey data with facility siting and structures and facilities were reviewed along with any and construction associated with the plant. all sample data for the site prior to excavation and construction

CY-05-243 ATTACHMENT 1 A REVIEW OF THE "PHASE 2 WORK PLAN" TO IDENTIFY TASKS VS TASK-COMPLETED AS PER THE SCOPE OF THE DOCUMENT Variations How and/or where Task Activity and scope Objective How performed from work is the performance plan documented?

Present results of geologic To evaluate the geologic Geologic outcrop and structures -NA- Task 1 Summary Report mapping of outcrops to the framework for a stable siting of were mapped in the immediate east of the plant, and a review a nuclear plant, and verify that vicinity of the HNP and compared to of the "overburden" and platform was not degraded the original maps and data to bedrock geology including during construction in addition develop an understanding of the pre- and post-construction to developing a basic geologic bedrock surface changes due to plant bedrock contour maps footprint. construction. Bedrock surface maps were prepared Analyze the potential To assess the consolidated and Maps, boreholes, design and -NA- Task 1 Summary Report preferential pathways for unconsolidated geologic construction drawings and groundwater flow deposits and their relationship groundwater monitoring data to structures and evaluate revealed where the building groundwater flow and identify supports are constructed directly potential preferential flow onto bedrock, foundations extend pathways. well into the unconsolidated soils, and the density of those structures will provide an impediment to groundwater flow and transport Groundwater flow in bedrock was established as a preferential pathway for flow.

Present the locations of Identify existing boring Locate and verify the positions of, -NA- Task 1 Summary Report borings and existing locations and uses then total depth, and water table elevation monitoring wells, incorporate the data and results in existing monitoring wells. Assess hydrogeologic data and SOC into structural, stratigraphic, existing cross sections.

concentrations obtained and hydrogeologic understanding, Develop conceptual site model The objective is to collate, digest Integrate existing information -NA- Preliminary CSM in Task 1 and condense the acquired data into (hydrogeological, contamrinant Summary Report formats from which a conceptual distribution, geochemistry) into Revised CSM in model of the flow structure, conceptual site model and revise as Hydrogeologic Conceptual Site transport mechanisms, plume new information is developed. Modelfor tihe HaddainNeck definition and potential source Plant,Haddarn Neck, areas can be generated Connecticut June 2005

CY-05-243 ATTACHMENT 1 A REVIEW OF THE "PHASE 2 WORK PLAN" TO IDENTIFY TASKS VS TASK-COMPLETED AS PER THE SCOPE OF THE DOCUMENT Variations How and/or where Task Activity and scope Objective How performed from work is the performance plan documented?

2 Simultaneous collection of To determine the influence of tidal A network of 30 data-logging -NA- Task 1 Summary Report surface elevation data in the effects on the groundwater pressure transducers was installed in Task 2 Supplemental river, canal and adjacent monitoring wells on-site and in the Characterization Report monitoring wells. Connecticut River to record water and subsequent Semi-elevations Annual Groundwater Monitoring Reports Overburden and bedrock To supplement the current 72-hour Aquifer pumping test 25 bedrock borings, Task 2 Supplemental hydrogeological understanding of the geology and performed in the unconsolidated ranging from 10 feet Characterization Report characterization through hydrogeology at the HNP. formation. to 50 feet in depth and subsequent Semi-drillin& soil sampling rock Packer testing, geophysical logging, were investigated in Annual Groundwater coring, downhole logging camera logging. and hydrophysical the former tank Monitoring Reports (geophysics), hydraulic logging of bedrock boreholes. farm area. These conductivity, overburden Examination of rock cores collected borings were used testing. transmissivity and from borings. to characterize bedrock interconnectivity Transducer network records were bedrock in lieu of evaluated to identify hydraulic the initially-responses to pumping and packer planned boring testing. 103B. An additional monitoring well has been installed in the general vicinity identified for 103B to monitor water quality near the tank farm source area Installation, sampling and To verify the background levels in Monitoring wells MW-118A, MW- -NA- Task 2 Supplemental radiological analyses of groundwater, and establish 119, MW-120, MW-121A, MW-122, Characterization Report groundwater from onsite naturally occurring radiological MW-123, MW-124, MW-125, MW- and subsequent Semi-solitary and clustered substances 130, MW-131, MW-132, MW-133, Annual Groundwater monitoring wells and the MW-134, MW-135 have been Monitoring Reports residential installed. Wells MW-122D and MW-former Schmidt residential 106D were replaced to correct water supply defective seals. Wells destroyed during demolition in the industrial area are being replaced as demolition is completed.

CY-05-243 ATTACHMENT 1 A REVIEW OF THE "PHASE 2 WORK PLAN" TO IDENTIFY TASKS VS TASK-COMPLETED AS PER THE SCOPE OF THE DOCUMENT Variations How and/or where Task Activity and scope Objective How performed from work is the performance plan documented?

Radiological groundwater To build a well across the river The well design has been completed -NA- To be documented in quality investigation opposite from the HNP and evaluate the and the easements are in process for subsequent Semi-Annual the river from the site groundwater for possible man- the drilling location. Data from the Groundwater Monitoring made radionuclides deep bedrock "Westbay" wells have Reports been evaluated and have been incorporated into the drilling and sampling plan for these wells.

3 Evaluation of fate and To constiuct a model to forecast the The groundwater addresses the -NA- Groundwater Modeling transport modeling nature and extent of potential or hydrologic parameters, completeness Report (December 2005) actual plumes and concentrations of of the data set, plume characteristics those plumes at UNP and future movement. The model is constructed using MODFLOW.

Landfill area groundwater Downgradient monitoring of the Use the existing monitoring wells for -NA- Semi-Annual Groundwater monitoring landfill area sampling groundwater, quarterly. Monitoring Reports Groundwater sampling and Obtain quarterly samples from Sampling continues on a quarterly -NA- Serni-Annual Groundwater analyses specified wells and analyze for H3, basis and is presented in semi-annual Monitoring Reports B, alpha and gamma emitting reports nuclides, and Sr-90 Groundwater monitoring Compile a record of the monitoring Sample and assimilate the analytical -NA- Semi-Annual Groundwater reports well water level activities, results then incorporate them into Monitoring Reports barometric and precipitation effects groundwater and contaminant on groundwater, sampling and plume trend maps while using the analytical results, and plume corrected water level measurements modifications due to new and effects from natural occurring information. recharge. The report will inulude summary tables of the sampling and field notes, discussion of the results and recommendations for revisions to the plan.

Retrieved from "https://kanterella.com/w/index.php?title=CY-05-243,_Transmittal_of_the_Phase_2_Hydrogeologic_Investigation_Work_Plan,_Task_3_Deliverable_-_Groundwater_Modeling_Report&oldid=2197738"