USGS assistance to USEPA on the remedial investigation and feasibility study of the Puchack well field Superfund site, Pennsauken, New Jersey
New Jersey WSC Archived Projects
Puchak well field is located in Pennsauken Township, an area with significant pumpage from the Potomac-Raritan-Magothy aquifer system well fields owned by the City of Camden Water Department and the Merchantville-Pennsauken Water Commission. Ground water contamination from a chromium plume affecting the wells at the Puchak well field resulted in termination of the use of the well field for potable water in 1984. The goal of this study was to evaluate the long-term impact the contamination could have within the well field.
START DATE: 21-SEP-1998
END DATE: 30-SEP-2016
PROJECT NUMBER: 2454ABA (NJ170)
OVERVIEW:
Puchak well field is located in Pennsauken Township, an area with significant pumpage from the Potomac-Raritan-Magothy aquifer system well fields owned by the City of Camden Water Department and the Merchantville-Pennsauken Water Commission. Ground water contamination from a chromium plume affecting the wells at the Puchak well field resulted in termination of the use of the well field for potable water in 1984. The USGS, in cooperation with the US Environmental Protection Agency and Camp, Dresser, and McKee (CDM) Inc., is using an existing ground-water flow model (Pope and Watt, 2004 and Pope and Watt, 2005) to study the effects of pumpage from wells surrounding the Puchak well field. Model results will aid in the proper design and evaluation of a Pilot Amendment Injection Test. The normal, short-term variability of pumpage from the well fields, stemming from changes in demand, rotation of production sequencing, maintenance down time, etc., is likely to have a significant impact on the hydrologic system and may have a significant impact on conditions controlling a long-term remediation process at the superfund site and on the ability to identify likely source areas.
The initital township-scale ground-water flow model was upgraded with more recent water-use data (2001-2007) and recalibrated to evaluate the effects of short-term variations in pumpage. The sensitivity of the direction and travel time of ground-water flow was evaluated along pilot-test transects to the uncertainty associated with simulated hydrologic parameters and the effects of pumpage variability present in the 2001 to 2007 water-use data.
Project Objectives
The objectives of this study are to:
- Develop a detailed understanding of the ground-waterflow and the movement and the nature and extent of contaminants in the vicinity of the Puchack well field.
- Determine the capture-zone of the Puchack well field and other well fields in the Pennsauken Township area under various pumping and external-stress conditions.
- Assess the geochemical conditions in the area and determine the effect of ground-water remedial actions on chromium concentrations in the vicinity of the Puchack well field.
Statement of Problem
The City of Camden's Puchack well field, located in Pennsauken Township, Camden County New Jersey, has been impacted by a plume of dissolved chromium and volatile organic compounds. A treatment plant to remove these contaminants is planned. The operation intent for the Puchack well field is to capture the plume, preventing its spread to other water-supply wells in the area. In order to complete the design and operate the plant, the nature and extent of contamination and the transport pathways must be determined. At present, there are uncertainties about the source, extent, and direction of movement of the contamination.
The New Jersey Department of Environmental Protection (NJDEP) has identified several potential sources of the contamination. Because of the industrialized nature of this area, it is possible that other sources may exist. The hydrogeologic framework is complex. In several areas, some of the confining units that separate the aquifers from surface contaminant sources may be absent or leaky, providing a tortuous pathway from contaminant transport. Past and future distributions of groundwater withdrawals have and will continue to influence the position of the plume and the direction of contaminant travel. In addition, the geochemistry affecting the transport of the chromium is very complex and requires detailed analysis of transport from a geochemical perspective. Transport of contaminants must be understood so that a viable remedial plan can be developed.
Strategy and Approach
This project is composed of three separate phases to facilitate effective project planning and management, but will be conducted as one continuous effort. The first phase is proposed to be first six months duration. It involves the collection of specific water level and hydrogeologic data, an assessment of these data, and the development and calibration of a groundwater flow model. The hydrogeologic controls on contaminant migration will be defined using the hydrostraigraphic framework developed previously for the area, potentiometric surface maps, water use, and the current understanding of geochemical processes. The development and calibration of the groundwater flow model will be completed to assess likely contaminant pathways using various particle tracking scenarios, and to understand the influence former and future groundwater withdrawals have on contaminant migration in the area. Planning for additional work tasks will be driven by the findings of the first phase work effort. A report will be prepared detailing the construction, calibration, and use of the flow model.
The second phase of work will be about 12 months in duration immediately following the first phase. It will involve finalizing the work plan for the second phase activities and implementing the additional data collection required to improve the understanding of the flow of groundwater and the movement of contaminants in the Puchack well field area. Additional monitoring wells will be installed. Data obtained from these wells will be used to refine the hydrostratigraphic framework and provide locations for additional monitoring for water levels and groundwater quality. Laboratory analysis of core samples from specific aquifer and/or confining unit materials will be used to determine the adsorptive properties of the materials. Additional groundwater sampling will be conducted and the geochemistry will be analyzed. A groundwater transport model will be developed and calibrated concurrently with the data collection effort, integrating the latest findings. The model will be used simulate the contaminant transport conditions in a attempt to recreate the contaminant history.
The third phase to expected to be of about 1.5 year's duration. During this period a limited, final data collection effort is tentatively planned for the project. During this phase the groundwater transport model will be refined and used to examine the possible effects of migration of contaminants toward nearby well fields and explore a range remedial scenarios in support of remedial investigations and feasibility studies to be conducted by the EPA's RI/FS contractor. A final report will be prepared detailing the construction of the groundwater transport model and the scenarios that were run. In addition, a report will be prepared summarizing the assessment of the conditions in the Puchack well field area that will include the hydrostratigraphic framework, groundwater quality, groundwater levels, and extent of contamination. All field data and other relevant data will be included in this report.
DISCLAIMER: This webpage contains information about completed or inactive projects from the NJ Water Science Center. It has been created for historical purposes and may be a utility to locate published information. This page should not be considered an authoritative source. You are encouraged to contact the NJ WSC for more current information.
Puchak well field is located in Pennsauken Township, an area with significant pumpage from the Potomac-Raritan-Magothy aquifer system well fields owned by the City of Camden Water Department and the Merchantville-Pennsauken Water Commission. Ground water contamination from a chromium plume affecting the wells at the Puchak well field resulted in termination of the use of the well field for potable water in 1984. The goal of this study was to evaluate the long-term impact the contamination could have within the well field.
START DATE: 21-SEP-1998
END DATE: 30-SEP-2016
PROJECT NUMBER: 2454ABA (NJ170)
OVERVIEW:
Puchak well field is located in Pennsauken Township, an area with significant pumpage from the Potomac-Raritan-Magothy aquifer system well fields owned by the City of Camden Water Department and the Merchantville-Pennsauken Water Commission. Ground water contamination from a chromium plume affecting the wells at the Puchak well field resulted in termination of the use of the well field for potable water in 1984. The USGS, in cooperation with the US Environmental Protection Agency and Camp, Dresser, and McKee (CDM) Inc., is using an existing ground-water flow model (Pope and Watt, 2004 and Pope and Watt, 2005) to study the effects of pumpage from wells surrounding the Puchak well field. Model results will aid in the proper design and evaluation of a Pilot Amendment Injection Test. The normal, short-term variability of pumpage from the well fields, stemming from changes in demand, rotation of production sequencing, maintenance down time, etc., is likely to have a significant impact on the hydrologic system and may have a significant impact on conditions controlling a long-term remediation process at the superfund site and on the ability to identify likely source areas.
The initital township-scale ground-water flow model was upgraded with more recent water-use data (2001-2007) and recalibrated to evaluate the effects of short-term variations in pumpage. The sensitivity of the direction and travel time of ground-water flow was evaluated along pilot-test transects to the uncertainty associated with simulated hydrologic parameters and the effects of pumpage variability present in the 2001 to 2007 water-use data.
Project Objectives
The objectives of this study are to:
- Develop a detailed understanding of the ground-waterflow and the movement and the nature and extent of contaminants in the vicinity of the Puchack well field.
- Determine the capture-zone of the Puchack well field and other well fields in the Pennsauken Township area under various pumping and external-stress conditions.
- Assess the geochemical conditions in the area and determine the effect of ground-water remedial actions on chromium concentrations in the vicinity of the Puchack well field.
Statement of Problem
The City of Camden's Puchack well field, located in Pennsauken Township, Camden County New Jersey, has been impacted by a plume of dissolved chromium and volatile organic compounds. A treatment plant to remove these contaminants is planned. The operation intent for the Puchack well field is to capture the plume, preventing its spread to other water-supply wells in the area. In order to complete the design and operate the plant, the nature and extent of contamination and the transport pathways must be determined. At present, there are uncertainties about the source, extent, and direction of movement of the contamination.
The New Jersey Department of Environmental Protection (NJDEP) has identified several potential sources of the contamination. Because of the industrialized nature of this area, it is possible that other sources may exist. The hydrogeologic framework is complex. In several areas, some of the confining units that separate the aquifers from surface contaminant sources may be absent or leaky, providing a tortuous pathway from contaminant transport. Past and future distributions of groundwater withdrawals have and will continue to influence the position of the plume and the direction of contaminant travel. In addition, the geochemistry affecting the transport of the chromium is very complex and requires detailed analysis of transport from a geochemical perspective. Transport of contaminants must be understood so that a viable remedial plan can be developed.
Strategy and Approach
This project is composed of three separate phases to facilitate effective project planning and management, but will be conducted as one continuous effort. The first phase is proposed to be first six months duration. It involves the collection of specific water level and hydrogeologic data, an assessment of these data, and the development and calibration of a groundwater flow model. The hydrogeologic controls on contaminant migration will be defined using the hydrostraigraphic framework developed previously for the area, potentiometric surface maps, water use, and the current understanding of geochemical processes. The development and calibration of the groundwater flow model will be completed to assess likely contaminant pathways using various particle tracking scenarios, and to understand the influence former and future groundwater withdrawals have on contaminant migration in the area. Planning for additional work tasks will be driven by the findings of the first phase work effort. A report will be prepared detailing the construction, calibration, and use of the flow model.
The second phase of work will be about 12 months in duration immediately following the first phase. It will involve finalizing the work plan for the second phase activities and implementing the additional data collection required to improve the understanding of the flow of groundwater and the movement of contaminants in the Puchack well field area. Additional monitoring wells will be installed. Data obtained from these wells will be used to refine the hydrostratigraphic framework and provide locations for additional monitoring for water levels and groundwater quality. Laboratory analysis of core samples from specific aquifer and/or confining unit materials will be used to determine the adsorptive properties of the materials. Additional groundwater sampling will be conducted and the geochemistry will be analyzed. A groundwater transport model will be developed and calibrated concurrently with the data collection effort, integrating the latest findings. The model will be used simulate the contaminant transport conditions in a attempt to recreate the contaminant history.
The third phase to expected to be of about 1.5 year's duration. During this period a limited, final data collection effort is tentatively planned for the project. During this phase the groundwater transport model will be refined and used to examine the possible effects of migration of contaminants toward nearby well fields and explore a range remedial scenarios in support of remedial investigations and feasibility studies to be conducted by the EPA's RI/FS contractor. A final report will be prepared detailing the construction of the groundwater transport model and the scenarios that were run. In addition, a report will be prepared summarizing the assessment of the conditions in the Puchack well field area that will include the hydrostratigraphic framework, groundwater quality, groundwater levels, and extent of contamination. All field data and other relevant data will be included in this report.
DISCLAIMER: This webpage contains information about completed or inactive projects from the NJ Water Science Center. It has been created for historical purposes and may be a utility to locate published information. This page should not be considered an authoritative source. You are encouraged to contact the NJ WSC for more current information.