£ ; te:_j> Break: ( Other: U. S. ENVIRONMENTAL PROTECTION AGENCY. * NEW ENGLAND *" OFFICE OF ENVIRONMENTAL MEASUREMENT & EVALUATION OFFICE OF ECOSYSTEM ASSESSMENT 60 WESTVIEW STREET, LEXINGTON, MA 02421 MEMORANDUM DATE: April 17, 2000 SUBJ: Ecological Screening of Preliminary Data and Recommendations for Additional Sampling, Mohawk Tannery, Nashua, New Hampshire FROM: Patti Lynne Tyler Aquatic Biologist/Ecological Risk Assessor TO: Neil Handler Remedial Project Manager Thank you for the opportunity to review and provide technical comments on the above referenced document. The only source available for this review was The New Hampshire Department of Environmental Services Final Site Inspection Prioritization Report (SIP) from 1996. This document summarizes data from a number of previous reports, however only a small fraction of the previously-collected data is presented in the SIP report. Also, the source and nature of the data presented in the SIP report is not always clear. A more detailed screening of surface water and sediment data would require use of some of the original reports. Based on the very limited data available in the SIP report, this preliminary screening of site-specific contaminants concentrations against relevant ecotoxicological benchmarks for surface water, soil and sediment strongly suggests that aquatic and terrestrial organisms associated with this area are being exposed to levels of contamination that could results in adverse biological effects. For example, concentrations of phenol, silver and zinc in surface water exceed relevant aquatic benchmark values for these chemicals. In addition, concentrations of cadmium, chromium, and lead in sediment exceed both LEL and SEL values, indicating potential risk to sediment dwelling organisms. Chromium and cadmium were detected in one surficial soil sample at levels that could be harmful to the soil invertebrate and plant communities. Other organisms such as birds and mammals may be at risk when they forage in the various habitats associated with the site such as the area adjacent to in the Nashua River or the surrounding upland areas.
Transcript
£;te:_j>Break: (
Other:U. S. ENVIRONMENTAL PROTECTION AGENCY. *
NEW ENGLAND *"OFFICE OF ENVIRONMENTAL MEASUREMENT & EVALUATION
OFFICE OF ECOSYSTEM ASSESSMENT60 WESTVIEW STREET, LEXINGTON, MA 02421
MEMORANDUM
DATE: April 17, 2000
SUBJ: Ecological Screening of Preliminary Data and Recommendations forAdditional Sampling, Mohawk Tannery, Nashua, New Hampshire
Thank you for the opportunity to review and provide technical comments on the abovereferenced document.
The only source available for this review was The New Hampshire Department ofEnvironmental Services Final Site Inspection Prioritization Report (SIP) from 1996.This document summarizes data from a number of previous reports, however only asmall fraction of the previously-collected data is presented in the SIP report. Also, thesource and nature of the data presented in the SIP report is not always clear. A moredetailed screening of surface water and sediment data would require use of some of theoriginal reports.
Based on the very limited data available in the SIP report, this preliminary screening ofsite-specific contaminants concentrations against relevant ecotoxicological benchmarksfor surface water, soil and sediment strongly suggests that aquatic and terrestrialorganisms associated with this area are being exposed to levels of contamination thatcould results in adverse biological effects. For example, concentrations of phenol,silver and zinc in surface water exceed relevant aquatic benchmark values for thesechemicals. In addition, concentrations of cadmium, chromium, and lead in sedimentexceed both LEL and SEL values, indicating potential risk to sediment dwellingorganisms. Chromium and cadmium were detected in one surficial soil sample at levelsthat could be harmful to the soil invertebrate and plant communities. Other organismssuch as birds and mammals may be at risk when they forage in the various habitatsassociated with the site such as the area adjacent to in the Nashua River or thesurrounding upland areas.
To better identify those aquatic and terrestrial receptors associated with the tannery facility and its surroundings, a field visit should be performed to collect additional information and a more detailed description of those habitats associated with the site. In addition, a Quality Assurance Project Plan (QAPP) should be developed to collect an expanded set of surface soil, sediment, surface water and groundwater samples for the full suite of chemical analyses. This QAPP should identify data quality objectives for field sampling and laboratory analysis of surface water, surface soil, and sediment to support a screening level ecological risk assessment (SLERA). The purpose of the SLERA would be to identify a list of COPCs to be incorporated into a baseline ecological risk assessment
I look forward to continuing to work with you on this project and should you have any questions or comments associated with this review, please do not hesitate to contact me.
cc: Peter Nolan EPA/OEME/ECA
Ecological Screening of Preliminary Data and Recommendations for Additional Sampling
Mohawk Tannery
Nashua, New Hampshire
INTRODUCTION
The ecological screening of preliminary data and recommendations for additional sampling focus on the evaluation of data compiled in the Final Site Inspection Prioritization Report for the Mohawk Tannery, Nashua, New Hampshire, dated November, 1996 (SIP report). This screening of preliminary data has been prepared according to procedures recommended in the EPA document; Ecological Risk Assessment Guidancefor Superfund, Process for Designing and Conducting Ecological Risk Assessments, Draft Final (EPA 540/R-97-006) (EPA, 1997). The purpose of this review is to evaluate current analytical data collected from the site and compare that data to published ecological benchmarks and to identify contaminants that might pose a potential risk to aquatic or terrestrial organisms. Background information on the site is only briefly summarized in order to provide a context for subsequent steps.
This screening of preliminary data consists of a Screening-level Problem Formulation and Ecological Effects Evaluation, and contains the following sections:
f Site history
f Previous Investigations
* Environmental setting
4 Nature and extent of contamination
t Exposure Pathway Analysis
4 Screening-level methodology
+ Results of the screening-level evaluation
4 Discussion and Recommendations
This screening of preliminary data is based on the use of limited site-specific information on the presence of ecological receptors and other natural features, therefore some of the sections listed above contain only a brief summary of the
information.
SITE HISTORY
The Mohawk Tannery also known as Granite State Leathers (GSL) operated from 1924 to 1984 under the management of Mr. Warren Kean. During the operation of the tannery, alkaline and acidic waste streams were produced. The alkaline waste stream, was the result of the pre-tanning preparation process while the acid waste stream was the result of the tanning process itself. The 50,000 gallons per day (G.P.D.) of alkaline waste was composed primarily of undissolved lime and proteinaceous solids such as, hair, fleshings and hide scraps. The 100,000 G.P.D. of acid waste consisted mostly of spent chromium tanning materials and some hide residue "pickling" wastes. Tannery's effluent treatment practices from 1924 to 1960's are little known due to incomplete records. However, it is assumed that prior to the establishment of two lagoons (Area I and II) in the 1960's, waste products were discharged directly to the Nashua River. At that time, the alkaline and acid waste stream effluent were combined and the liquid fraction overflow from the lagoons was discharged to the Nashua River. During the 1970's approximately 1971 to 1973/1974, a separate treatment process for the waste streams was put in place. The alkaline effluent was pumped from the main facility underground to an elevated wooden sluiceway through which was transported to a screen building for removal of solids. After removing solids, the effluent was transported through a second wooden sluiceway to the settling lagoons first to Area II and then to Area I for long-term deposition.
PREVIOUS INVESTIGATIONS
Several studies and sampling investigations have been conducted by the New Hampshire Department of Environmental Services (NH DES) and several environmental consulting firms from 1985 to 1995. However, the most comprehensive environmental investigation was the "Phase II Hydrogeologic Study and Conceptual Closeout Plan" conducted in 1985 by Goldeberg-Zoino and Associates, Inc. (GZA). The only source available to review and provide analytical data for the screening of preliminary data and ecological effects evaluation was The New Hampshire Department of Environmental Services Final Site Inspection Prioritization Report (SIP) from 1996. This document summarizes the data from the various previous reports, however only a small fraction of the previously-collected data is presented in the SIP report. Also, the source and nature of the data presented in the SIP report is not always clear. In one instance the same analytical results appear to have been reported as both surface water listed in a table, and sediment data depicted on a map. A more detailed screening of surface water and sediment data would require use of some of the original reports.
ENVIRONMENTAL SETTING
The Mohawk Tannery property is located in the lower Merrimack River basin on the eastern bank of the Nashua River (see Figure 1) in a residential area, one mile west of the City of Nashua. The site is composed of two abutting properties, a 15 acre developed parcel to the north containing the tannery facility and another approximately 15 acres undeveloped parcel to the south. To the east of the site is a meander of the Nashua River, and beyond the river is a shopping center. To the north and west are residential areas. The Mine Falls Park is located south of the site. Very little can be discerned about the ecological setting from information provided in the SIP report, except for the information from the U. S. Geological Survey (USGS) Nashua North Quadrangle map provided in the report.
Nine potential Source Areas were identified in the SIP. Area I and II are located 20 to 30 feet east of the Nashua River while Areas III, IV, V and VI are located 260, 200, 370 and 400 feet east of the Nashua River ( see Figure 2). All six areas are within the 100year flood zone. Area VII is the most southern source of contamination while Area VIII, the Fimbel Door Landfill, is located to the north of the tannery facility. Area IX is the NPDES discharge pipe and the Lagoon drainage line both at the edge of the Nashua River bank.
NATURE AND EXTENT OF CONTAMINATION
Sampling at the tannery facilities has been limited, and only a small portion of the available data is presented in the SIP report. The analytical data summary presented in the Final Site Inspection Prioritization Report (1996) is sufficient enough to provide the rationale for a more in-depth investigation. The available data for each medium of ecological interest (surface soil, surface water, and sediment) are described below. It is most likely that substantially more data is available in the source documents used in the preparation of the SIP report.
Most of the soil data in the SIP report are from samples collected by GZA in 1985, from depths between 2.5 and 12 feet below ground surface. These samples are not relevant to ecological risk analysis, because direct contact with any terrestrial receptors is unlikely to occur at depths greater than one foot. However, analytical data presented from a single surface soil sample collected by the NH DBS at the drain pipe located 10 feet from the water's edge on the eastern bank of the Nashua River includes elevated levels of chromium, cadmium, and lead.
The primary source of sediment data appears to be from samples collected in the Nashua River by NHDES on October 8, 1993. These data are presented in a series of hand-drawn maps of the Nashua River near the Mohawk Tannery outfall pipe. The
maps show the sample locations, with concentrations of cadmium, chromium, and lead at each location. Some of this data appears to have been inadvertently presented as surface water data in Table 4 of the SIP report, however the text and Table 3 of the SIP report support interpreting these data as sediment data. Sediment samples from the Nashua River contained elevated levels of chromium, cadmium and lead.
As mentioned above, some of the data presented as surface water data in Table 4 of the SIP report may in fact be sediment data, however the samples labeled "NPDES Effluent Data" wereevaluated as surface water data for purposes of this review. Additional surface water data may be available in the source documents.
In addition to the samples discussed above, previous investigations conducted by various environmental consultants have detected elevated levels of metals and VOC's in sludges, soils and groundwater at both the Mohawk Tannery and the Fimbel Door facilities. There is reason to suspect that surface soil and seep contamination may exist in these areas, however additional sampling should be conducted targeting surficial areas accessible to ecological receptors.
Several 55 gallon drums may be likely another source of contamination. These drums were originally from the Amoskeag Leather Co., and were transported to the Mohawk facility and dumped into the Fimbel Door Landfill. Other sources of potential contamination are two discharges of "sodium hydro sulfate" discussed in the SIP report. These discharges are described as consisting of separate discharges of approximately 100 gallons and 1282 gallons. These discharges were accidentally released in the vicinity of the storage tank located to the east of the main facility.
EXPOSURE PATHWAY ANALYSIS
The Mohawk Tannery property is located within the Merrimack River basin, and adjacent to the Nashua River. The SIP does not provide a physical description of the site. However, the report provides a general inventory of the amount of wetland frontage within 15 miles along the Nashua River and the Merrimack River (0.66 linear miles).
All sensitive environments outlined in the SIP Report were identified by the New Hampshire Natural Heritage Program and the Massachusetts Natural Heritage Program, endangered species information was also provided. The report identifies Area I and Area II (depositional lagoons) as wetlands. The report also identifies the following species as present in the vicinity of the tannery property (0.25 miles to 3-4 miles): banded sunfish, birds foot violet, burgrass, eastern hognose snake, northern prickly ash, goats rue, bald eagle, Siberian chives, American plum, swamp azalea, hairy stargrass and geometric moth. Although, the actual location of these species was not
provided, northern prickly ash, a tree listed as a New Hampshire endangered species reportedly exists within a 1 to 2 mile radius of the site.
The Nashua River provides habitat to a number of warmwater species such as yellow perch, sunfish and largemouth bass. The Nashua River is also stocked with anadromous species, approximately 200 shad and 600 alewife are stocked annually. In addition, tributaries of the Nashua River are stocked with trout.
The site is located one mile west of the City of Nashua in a residential area hence it is possible that terrestrial habitat available for wildlife species is limited but this will require further evaluation and confirmation.
SCREENING-LEVEL METHODOLOGY
This section presents a comparison of site-specific surface water, sediment, and soil contaminant concentration data with ecotoxicological benchmarks appropriate to those media. This screening process identifies the Contaminants of Potential Concern (COPCs) for each medium. Chemicals selected as COPCs warrant further investigation and need to be evaluated within a baseline ecological risk assessment. Additional sampling and analysis of surface water, soils, and sediments will be necessary to derive a more complete list of COPCs. This preliminary screening is only based on one sample each of surface soil and surface water, and only a few sediment samples. Most of these samples appear to have been analyzed for metals, and, in the case of surface water, volatile organic compounds (VOCs).
Table 1 presents the surface water analytical results from the NPDES outfall, which is shown in Figure 2. These data were compared to freshwater Federal Ambient Water Quality Criteria (AWQC). Table 1 includes the selection of inorganic COPCs for surface water. The benchmarks selected for surface water are the acute (Criterion Maximum Concentration or CMC) and chronic (Criterion Continuous Concentration or CCC) AWQC for freshwater. These values are cited in the National Recommended Water Quality Criteria - Correction (EPA, 1999).
The AWQC are Applicable or Relevant and Appropriate Requirements (ARARS) for surface waters and were used when available. The AWQC are derived from at least eight LC50s (concentration lethal to 50% of organisms tested) and three chronic values (CVs), encompassing a variety of aquatic species. They are designed to be protective of 95% of aquatic life. Both the criterion continuous concentration (CCC) and criterion maximum concentration (CMC) were used in this evaluation. The CCC is an estimate of the highest concentration of a material in surface water to which an aquatic community can be exposed indefinitely without resulting in an unacceptable effect (EPA, 1999). In contrast, the CMC is an estimate of the highest concentration of a
material in surface water to which an aquatic community can be exposed briefly without resulting in an unacceptable effect (EPA, 1999). For certain metals, the AWQC can be adjusted to account for site-specific hardness, however in this case the hardness of the receiving water was not known and a default value of 100 mg/L as CaCO3 was used.
For some chemicals, AWQC values are not available. Other screening benchmarks for these chemicals were found in Suter and Tsao (1996). This document represents a compilation of screening benchmarks for surface waters developed for the Oak Ridge Reservation by the Environmental Sciences Division of the Oak Ridge National Laboratory. The Tier II secondary acute and secondary chronic values were developed according to procedures described in the EPA document Proposed Water Quality Guidance for the Great Lakes System. These values are derived in a manor similar to that used to develop AWQC, except that fewer data are required to develop Tier II values. In addition, a water quality criterion developed by the U.S. EPA Great Lakes Initiative and cited in Suter and Tsao (1996) was used for phenol.
Site-specific sediment data was compared against sediment guidelines prepared by the Ontario Ministry of the Environment (OMOE) to assist environmental managers assess sediment quality (Jaagumagi et al. 1995). The major objective of the sediment quality guidelines is to provide protection of biological resources against the lethal and sub-lethal effects of contaminated sediments. These biological resources include organisms that could be affected directly; that is, the benthic species that live in or feed on the sediment and water column organisms that could absorb contaminants released from the sediment to water and/or through the consumption of benthic organisms; and those affected indirectly, such as non-aquatic consumers (humans and wildlife) or top aquatic predators such as fish.
These biologically based sediment guidelines have been derived to protect those organisms that are directly affected by contaminated sediment and to protect against biomagnification of contaminants through the food chain. The lowest effect level (LEL) indicates a level of sediment contamination that can be tolerated by the majority of benthic organisms. A severe effect level (SEL) indicates a level at which pronounced disturbance of the sediment-dwelling community can be expected. The SEL is a sediment concentration of a compound that would be detrimental to the majority of benthic species.
The maximum contaminant concentrations detected in site-specific sediment samples presented in the SIP report were compared to the Lowest Effect Levels (LELs) and the Severe Effect Levels (SELs) from the Ontario Ministry of the Environment (OMOE) sediment quality guidelines (Jaagumagi et al. 1995). This comparison is found in Table 2. Concentrations exceeding low and high benchmarks are highlighted in this table.
The soil evaluation was based on the single available surface soil sample presented in
the SIP report. Soil evaluation (Table 3) was conducted using benchmarks designed to be protective of soil invertebrates and terrestrial plants. These benchmarks were developed by Will and Sutter II (1995) and Effroymson et al (1997) for the Oak Ridge National Laboratory in Oak Ridge, Tennessee. Many of the benchmarks are based on only a few experiments, and the overall confidence level in these benchmarks is low to medium, however they can give some indication of the degree of risk to soil invertebrates (i.e., earthworms) or terrestrial vegetation. Currently, there are no widely-accepted benchmarks for screening soil concentrations.
RESULTS OF THE SCREENING-LEVEL EVALUATION
The one surface water sample collected from the NPDES effluent data indicated the presence of organic compounds, including methylene chloride and phenol, as well as arsenic, silver and zinc (Table 1). The concentration of phenol was above the Great Lakes acute value for this chemical. The concentration of silver was more than one order-of-magnitude over the acute AWQC for this metal. In addition, silver is very toxic and further evaluation of the nature and extent of this metal will be necessary. The concentration of zinc exceeded the acute and chronic criterion for this metal. These findings indicate that there is potential risk to aquatic organisms from organic and inorganic chemicals, based on the limited data available for evaluation. Adverse effects to aquatic organisms that could result from exposure to these elevated inorganic concentrations could consist of an increase in mortality and decrease in growth and reproduction.
Sediment analysis indicated values of cadmium, chromium and lead orders-ofmagnitude above the LEL and SEL values for these metals (Table 2). If these concentrations are indicative of current conditions, there is potential risk of adverse effects on benthic (sediment-dwelling) organisms, and possibly to higher organisms that may consume benthic organisms, especially since cadmium does bioaccumulate. It should be noted that this evaluation was limited to data on a few metals, and other inorganic and organic chemicals might be present as well.
Soil analysis was limited as the analysis was based on one sample collected at the effluent pipe to the Nashua River (Table 3). This sample showed chromium concentrations exceeding the toxicity values for earthworms and terrestrial plants. Cadmium concentrations exceeded the benchmark values for toxicity to earthworms. As is the case for soil, it is not clear whether the soil sample was analyzed for chemicals other than metals, and additional chemicals may be present at potentially harmful levels.
Based on the limited data available and evaluated with respect to a potential risk to both aquatic and terrestrial receptors, it will be necessary to conduct additional
sampling and analyses to determine the complete nature and extent of contamination associated with this site. It should also be noted that there were no suitable data for ecological risk analysis from the Fimbel Landfill area, and this area may contain chemicals similar to those found at the Mohawk Tannery.
DISCUSSION AND RECOMMENDATIONS
Based on the very limited data available in the SIP report, this preliminary screening of site-specific contaminants concentrations against relevant ecotoxicological benchmarks for surface water, soil and sediment strongly suggests that aquatic and terrestrial organisms associated with this area are being exposed to levels of contamination that could results in adverse biological effects. For example, concentrations of phenol, silver and zinc in surface water exceed relevant aquatic benchmark values for these chemicals. In addition, concentrations of cadmium, chromium, and lead in sediment exceed both LEL and SEL values, indicating potential risk to sediment dwelling organisms. Chromium and cadmium were detected in one surficial soil sample at levels that could be harmful to the soil invertebrate and plant communities. Other organisms such as birds and mammals may be at risk when they forage in the various habitats associated with the site such as the area adjacent to in the Nashua River or the surrounding upland areas.
To better identify those aquatic and terrestrial receptors associated with the tannery facility and its surroundings, a field visit should be performed to collect additional information and a more detailed description of those habitats associated with the site. In addition, a Quality Assurance Project Plan (QAPP) should be developed to collect an expanded set of surface soil, sediment, surface water and groundwater samples for the full suite of chemical analyses. This QAPP should identify data quality objectives for field sampling and laboratory analysis of surface water, surface soil, and sediment to support a screening level ecological risk assessment (SLERA). The purpose of the SLERA would be to identify a list of COPCs to be incorporated into a baseline ecological risk assessment.
Currently, it does not appear that there is a well-defined set of chemicals of potential concern for this site. The analyte list for all surface water and sediment locations should include the EPA target analyte list (TAL) and the target compound list (TCL). Sediments should be analyzed for total organic carbon (TOC), grain size and acid volatile sulfides/simultaneously extracted metals (AVS/SEM). Unfiltered and filtered surface water samples should be collected and also analyzed for the full TAL and TCL. Surface water samples should be analyzed for hardness since a set of inorganic AWQC are hardness dependent.
In development of the QAPP for additional sampling and analysis at the site, the following considerations should be taken in to account, in order to provide useable data for ecological risk assessment purposes:
8
Sediment samples should be collected for analysis for TAL and TCL, acid volatile sulfides/simultaneous extracted metals (AVS/SEM), grain size, and total organic carbon. Sample depths of 1-6" for are suitable for all sediment parameters except AVS/SEM, which should be taken as a discreet sample in the 1-10 cm depth.
A reconnaissance should be made for a few sediment samples to assess the percent solids of representative sediments, in order to avoid problems with high moisture content and elevated quantitation limits that do not meet data quality objectives.
Volatile organic compounds in sediment should use EPA SW846 Method 5035.
Data quality objectives should be established to match quantitation limits against suitable ecological benchmarks for each medium.
Surface water should be analyzed for dissolved oxygen, pH, specific conductance, and temperature (on-site), and TAL and TCL parameters for both filtered and unfiltered samples.
Soil samples should be taken at the 0-1' depth.
From the information currently available, surface soils should be analyzed in areas where suitable terrestrial habitat coincides with areas of known or suspected contamination. Sediment samples should be taken upstream of the site, at the site, and downstream of the site in the Nashua River. Surface water samples should be taken in the Nashua River, as well as in any seeps associated with the landfill, and in any nearby wetland areas potentially affected by the site.
REFERENCES
Effroymson, R. A., M.E. Will, G.W. Suter. 1997. Toxicological Benchmarks for Screening Contaminants of Potential Concern for Effects on Soil and Litter Invertebrates and Heterotrophic Process: 1997 Revision. Prepared for the U.S. Department of Energy, November, 1997. Publication Number ES/ER/TM-126/R2.
New Hampshire Department of Environmental Services. 1996. Final Site Inspection Prioritization Report for Mohawk Tannery, Nashua, New Hampshire . CERCLIS No. NHD981889629. November, 1996
Jaagumagi, R., D. Persaud and D. Bedard. 1995. Ontario's Approach to Sediment Assessment and Remediation. Second SETAC World Congress (16th Annual Meeting) Vancouver, British Columbia, Canada, November 5-9, 1995.
U.S. Environmental Protection Agency (USEPA). 1999. National Recommended Water Quality Criteria - Correction. Office of Water, April, 1999. EPA 822-Z-99-001.
U.S. Environmental Protection Agency (USEPA). 1997. Ecological Risk Assessment Guidance For Superfund: Process for Designing and Conducting Ecological Risk Assessments, Interim Final. Environmental Response Team, Edison New Jersey. June 5, 1997.
U.S. Environmental Protection Agency (USEPA). 1996. Office of Solid Waste and Emergency Response (OSWER). ECO Update: Ecotox Thresholds. EPA 540/F95/038.
Will, M.E. and G.W. Sutter II. 1995. Toxicological Benchmarks for Screening Contaminants of Potential Concern for Effects on Terrestrial Plants: 1995 Revision. Prepared for the U.S. Department of Energy, September, 1995. Publication Number ES/ER/TM-85/R2.
10
Tables
Table 1
Screening of Organic and Inorganic Chemicals in Surface Water Mohawk Tannery, Nashua, New Hampshire
i
Acute Chronic Chemical Concentration (1} Benchmark (2) Benchmark (3)
NOTES. (1) value is the concentration reported in the single NPDES water sample from the SIP report.
(2) values for silver and zinc are the AWQC (EPA, 1999) CMC and CCC values. For methylene chloride and arsenic, Tier II secondary acute and secondary chronic values were used, assuming arsenic in the form of arsenic V. For phenol, ambient water
quality criteria from the Great Lakes Initiative (cited in Suter and Tsao, 1996) were used.
— = Not Available - no criterion for this chemical
= Indicates that the contaminant concentration exceeds the low benchmark at this static
bold text = Indicates that the contaminant concentration exceeds the high benchmark at this statio
Table 2
Screening of Inorganic Chemicals in Sediment Mohawk Tannery, Nashua, New Hampshire
} Maximum Concentration
Chemical ug/g dry wt. (1) i SEL (2) LEL (3) Cadmium 18,700 I 10 0.6 Chromium 313,000 I 110 26
Lead 163,000 250 31 Notes: (1) Maximum concentration among the NHDES sediment samples from
the Nashua River presented in the SIP report. (2) SEL = Severe Effect Level from Jaagumagi et al (1995). (3) LEL = Lowest Effect Level from Jaagumagi et al (1995).
= Indicates that the contaminant concentration exceeds the low benchmark at this station
bold text = Indicates that the contaminant concentration exceeds the high benchmark at this station
Jaagumagi, R., D. Persaud and D. Bedard. 1995. Ontario's Approach to Sediment Assessment and Remediation. Second SETAC World Congress (16th Annual Meeting) Vancouver, British Columbia, Canada, November 5-9, 1995.
Table 3
Screening of Inorganic Chemicals in Soil Mohawk Tannery, Nashua, New Hampshire
Toxicity to Toxicity to Earthworms (2) Terrestrial Plants (3)
Mercury o.oi 100 0.3 Notes (1) Concentration detected in the single surface soil sample taken near the NPDES outfall. (2) Concentration estimated to be toxic to earthworms, from
Effroymson et al (1997). (3) Concentration estimated to be toxic to terrestrial plants, from
Will and Suter (1995).
— indicates that no benchmark was available for the chemical.
bold text = Indicates that the contaminant concentration exceeds the benchmarkmark for earthworms at this location.
= Indicates that the contaminant concentration exceeds the benchmark for terrestrial plants at this station.
bold text = Indicates that the contaminant concentration exceeds the benchmark for both terrestrial plants and earthworms at this location.
