final: work plan tar creek ou4 ri/fs program · 2.0 site background and setting ... 2.2 physical...

FINAL: Work Plan Tar Creek OU4 RI/FS Program

Prepared for The Tar Creek Respondents and the

U.S. Environmental Protection Agency Prepared by

AATA INTERNATIONAL, INC.

Fort Collins, Colorado, USA November 2004

003035

003036

North Miami

- Figure 6.1 Org Chart.pdf

003037

Executive Summary This Work Plan (WP) is a planning document that outlines the scope of work for conducting a Remedial Investigation/Feasibility Study (RI/FS) for rural Operable Unit 4 (OU4) of the Tar Creek Superfund Site (Site) in Ottawa County, Oklahoma. Investigations on OU4 will address lead, cadmium and zinc contamination from mining and mill residues, and smelter wastes deposited in the rural areas of the Site by former mining-related operations. The scope of work for OU4 has been defined in the Administrative Order on Consent (AOC) entered into among the U.S. Environmental Protection Agency (EPA), Blue Tee Corp. (Blue Tee), Gold Fields Mining Corporation (Gold Fields), and the U.S. Department of Interior. The AOC (CERCLA Docket No. 6-03-01) requires that a Remedial Investigation and Feasibility Study (RI/FS) be conducted for the rural areas of the Site. As part of the scoping phase for the RI/FS, A Scoping Phase Work Plan and a Data Gap Analysis (DGA) report have been prepared and approved by EPA (AATA, 2004a; AATA, 2004b) The Site, a former zinc and lead mining area, is located in the northeastern portion of Ottawa County, Oklahoma, and is the Oklahoma portion of the Tri-State Mining District (District) of northeastern Oklahoma, southeastern Kansas and southwestern Missouri. The boundaries of the Site include an approximately 40 square mile surface area. Mining began in Ottawa County around 1900 and continued until the 1960’s. Significant quantities of mine and mill residues were generated by milling of lead and zinc ores. Approximately 2,900 acres in Oklahoma were overlain by mine and mill residues. Mine and mill residues and smelter wastes are the focus of OU4. Groundwater and surface water issues related to acid mine drainage were investigated as part of the OU1 investigations in the 1980’s. Residential and high access areas were addressed under OU2. Soils from the Eagle Picher Industrial facility at Cardin were investigated and addressed under OU3. The residues remaining on the surface at the Site are grouped into four major categories: development rock, chat, fine tailings, and smelter waste. Development rock includes waste rock and overburden. Chat includes gravel-sized and sand-sized particles leftover from the jigging and tabling gravity separation milling processes. Fine tailings are very fine sands and silt-sized particles, which were commonly deposited as a slurry to bermed areas or ponds referred to as flotation ponds or tailings ponds. Smelter wastes include smelting-derived slag as well as clinker and flux, which may also have been produced during smelting operations.

FINAL Work Plan - Tar Creek OU4 RI/FS Study

i

003038

This RI/FS WP identifies the technical approach and planned tasks for completing the RI/FS. It was prepared in accordance with the requirements of the AOC. The technical approach and tasks were identified during the preparation of the Scoping Phase Work Plan and the DGA, which included an evaluation of existing data, background information, and similar work performed at other mining-related sites in the District. The detailed field information gathering, sample collection and testing procedures for each task will be described in the Field Sampling Plan (FSP). The purpose of the OU4 RI/FS is to gather information sufficient to support an informed risk management decision regarding which remedy is most appropriate to address the risks to human and the environment associated with the mine and mill residues and smelter waste deposited on the Site by former mining-related operations. The objectives for the RI/FS activities are consistent with the National Contingency Plan (NCP) and include:

1. Identification of the nature and extent of contamination from accumulated mine and mill residues and smelter wastes and affected soils at the Site;

2. Definition and quantification of the transport of lead, zinc and cadmium from residues to air, water and soil;

3. Collection of necessary information to support the ecological and human health risk assessment for this OU; and

4. Collection of necessary data for the identification and evaluation of a number of potentially viable remedial alternatives to address risks to human health and the environment associated with lead, zinc and cadmium from accumulated mine and mill residues and smelter wastes and affected terrestrial areas of the Site.

The RI/FS WP contains the following components:

• A conceptual site model; • Information gathered during the scoping activities; • Preliminary evaluation of potential risks; • Data quality objectives (DQOs); • An outline of the RI/FS tasks; • Sampling strategies; • Project management methods; • Quality assurance methodologies; • Procedures for amending the Work Plan and the FSP; • A project schedule and list of deliverables.


ii

003039

Table of Contents

1.0 Introduction........................................................................................... 1

1.1 RI/FS Approach and Activities......................................................... 2 1.2 Work Plan Organization ................................................................... 3

2.0 Site Background and Setting................................................................. 4 2.1 Site History ....................................................................................... 4 2.2 Physical Setting................................................................................. 4

2.2.1 Physiography............................................................................. 4 2.2.2 Geology..................................................................................... 6 2.2.3 Mineralization and Ore Deposits .............................................. 6 2.2.4 Mining-Related Materials ......................................................... 7

2.2.4.1 Development Rock................................................................ 7 2.2.4.2 Chat ....................................................................................... 7 2.2.4.3 Fine Tailings ......................................................................... 8 2.2.4.4 Smelter Waste ....................................................................... 8

2.2.5 Hydrogeology ........................................................................... 8 2.2.6 Surface Water............................................................................ 9 2.2.7 Soils......................................................................................... 10 2.2.8 Climatology and Air Quality .................................................. 10 2.2.9 Population and Land -Use....................................................... 11 2.2.10 Ecology ................................................................................... 12

3.0 Initial Evaluations ............................................................................... 14 3.1 Conceptual Site Models .................................................................. 14 3.2 Identification of Analytes ............................................................... 14

4.0 Work Plan Rationale ........................................................................... 18 4.1 Data Needs and Data Quality Objectives........................................ 18 4.2 Work Plan Approach....................................................................... 21 4.3 Sampling Strategies ........................................................................ 22

4.3.1 Mapping of Surface Features .................................................. 22 4.3.2 Sampling of COPC Sources.................................................... 23

4.3.2.1 Mine and Mill Residues and Smelter Wastes ..................... 23 4.3.2.2 Soils – Transition Zone, Rural Residential, and Smelter-

Affected................................................................................... 23 4.3.2.3 Surface water ...................................................................... 24 4.3.2.4 Groundwater ....................................................................... 24

5.0 RI/FS Tasks......................................................................................... 25 5.1 Scoping Phase Planning Documents............................................... 27 5.2 Site Reconnaissance........................................................................ 27 5.3 Site Investigation ............................................................................ 28

5.3.1 Surface Feature Mapping and Aerial Imagery Analysis......... 29 5.3.2 Sampling and Analysis ........................................................... 29

5.3.2.1 Chat ..................................................................................... 29 5.3.2.2 Chat Base ............................................................................ 30 5.3.2.3 Fine Tailings ....................................................................... 31


iii

003040

5.3.2.4 Smelter Wastes.................................................................... 31 5.3.2.5 Soils - Background, Transition Zone, Rural Residential, and

Smelter-affected...................................................................... 32 5.3.2.6 Surface Water...................................................................... 33 5.3.2.7 Groundwater ....................................................................... 36 5.3.2.8 Biota.................................................................................... 36

5.4 Preliminary Site Characterization Summary .................................. 39 5.5 Human Health Risk Assessments ................................................... 40 5.6 Ecological Risk Assessment (ERA)................................................ 40 5.7 RI Report......................................................................................... 40 5.8 Treatability Studies ......................................................................... 41

5.8.1 Candidate Technologies Report .............................................. 41 5.8.2 Treatability Study Work Plan ................................................. 42 5.8.3 Treatability Study Evaluation Report ..................................... 43

5.9 Feasibility Study (FS) ..................................................................... 44 5.9.1 Objectives of the FS................................................................ 44 5.9.2 Overview of the FS Activities................................................. 44 5.9.3 Development and Screening of Remedial Alternatives .......... 45 5.9.4 FS Report ................................................................................ 47

6.0 Project Management and Organization............................................... 48 6.1 Project Management ....................................................................... 48

6.1.1 Project Team ........................................................................... 48 6.1.2 Project Coordination Among Agencies, Potential Responsible

Parties, and the Lead Contractor......................................................... 49 6.1.3 Schedule Management ............................................................ 49 6.1.4 Training Documentation ......................................................... 51 6.1.5 Data Management ................................................................... 51 6.1.6 Quality Assurance................................................................... 52

6.2 Procedures for Work Plan/SAP Amendments ................................ 52 6.2.1 Post-Approval Amendments - Additional Work .................... 53 6.2.2 Post-Approval Amendments - Other Reasons ........................ 53

6.2.2.1 Field Changes...................................................................... 53 6.2.2.2 Minor Modifications ........................................................... 53 6.2.2.3 Major Modifications ........................................................... 54

6.3 Summary of RI/FS Deliverables..................................................... 54 6.3.1 Monthly Progress Reports....................................................... 54 6.3.2 Project Deliverables and Review Conferences ....................... 54

7.0 Project Schedule.................................................................................. 58 8.0 References........................................................................................... 62


iv

003041

List of Tables Table 1. Ottawa County, Oklahoma Towns and Population, 2001........... 11 Table 2. CLP Inorganic Target Analyte List............................................. 17 Table 3. Data Quality Objectives for OU4 RI/FS..................................... 19 Table 4. Parameters, analytical methods and detection limits (MDL) for

laboratories.............................................................................................. 21 Table 5. Major RI/FS Tasks for Tar Creek OU4 ...................................... 25 Table 6. Major deliverables and milestones of the OU4 RI/FS ................ 56

List of Figures Figure 2.1 Aerial view of the Tar Creek Site, March 2004 ............................. 5 Figure 3.1 Conceptual Site Model – Human Health Exposure, Tar Creek Site

OU4......................................................................................................... 15 Figure 3.2 Conceptual Site Model – Ecological Receptor Exposure, Tar Creek

Site OU4.................................................................................................. 16 Figure 6.1 Project Organization Chart ........................................................... 50 Figure 7.1a Work Plan Tasks and Schedule .................................................. 59 Figure 7.1b RI Tasks and Schedule ................................................................ 60 Figure 7.1c FS Tasks and Schedule ................................................................ 61

List of Appendices Appendix 1. Abbreviations and Acronyms Appendix 2. Work Plan Revision Form


v

003042

1.0 Introduction This document is the RI/FS WP for OU4 for the Tar Creek Superfund Site (Site) located in Ottawa County, Oklahoma. OU4 will address lead, cadmium and zinc contamination from former mining and mill residues, and smelter wastes deposited in the areas of historical mining-related operations at the Site. The RI/FS WP was prepared in accordance with the requirements of the AOC entered into among the EPA, Blue Tee, Gold Fields, and the U.S. Department of Interior. The AOC (CERCLA Docket No. 6-03-01) requires that an RI/FS be conducted for the rural areas of the Site. The RI/FS WP presents the rationale, tasks and schedules for conducting the RI/FS for OU4 that is consistent with the Statement of Work (SOW) in the AOC. The Site is part of the Tri-State Mining District (hereinafter the District), which was one of the largest zinc/lead mining districts in the world, and included approximately 2500 square miles in southwestern Missouri, southeastern Kansas, and northeastern Oklahoma. The mining and milling of lead and zinc ores in the Oklahoma portion of the District since the early 1900's has resulted in residues being deposited on the ground near the former mining-related areas that contain lead, cadmium and zinc. The residues from milling include larger gravel to sand sized particles deposited in piles, locally known as chat piles, and finer residues from gravity separation and flotation processes that were typically deposited as a slurry to impoundments. Luza (1986) estimated that approximately 2,900 acres at the Site were overlain by residues. The Site was placed on the National Priorities List (NPL) in October 1981. The Site was initially investigated in the early 1980s and a Record of Decision (ROD) was signed on June 6, 1984. The selected remedial actions, completed in December 1986, addressed impacts of acid mine discharges on surface waters and the potential migration of acid mine waters from the Boone aquifer into the Roubidoux aquifer through abandoned wells. This action later became known as Operable Unit 1 (OU1). After 1994, EPA established three more operable units: Operable Unit 2, residential yard soils; Operable Unit 3, Eagle Picher's facility at Cardin, Oklahoma; and Operable Unit 4, mine and milling residues and smelter wastes of the rural areas of the Site. The objectives of the RI/FS for OU4 are consistent with the National Contingency Plan (NCP) and include:

• Identification of the nature and extent of contamination from accumulated mine and mill residues and smelter wastes and affected soils at the Site;

• Definition and quantification of the transport of lead, zinc and cadmium from residues to air, water and soil;


1

003043

• Collection of necessary information to support the ecological and human health risk assessment for this OU; and,

• Collection of necessary data for the identification and evaluation of a number of potentially viable remedial alternatives to address risks to human health and the environment associated with lead, zinc and cadmium from accumulated mine and mill residues and smelter wastes and affected terrestrial areas of the Site.

1.1 RI/FS Approach and Activities The general approach and specific tasks identified to complete the RI/FS were developed based upon a review of the available information regarding the history of mining at the Site, the physical conditions at the Site, and RI/FS activities conducted at other mining-related Superfund sites within the District. The overall approach was first defined in the SOW of the AOC and was refined based on the results of scoping phase activities. The scoping phase included the preparation of a Scoping Phase Work Plan (AATA, 2004a) and a Data Gap Analysis (DGA) report (AATA, 2004b). The RI/FS approach incorporates a series of integrated and phased activities that will allow the site conceptual model, project data needs, and remedial action alternatives to be further evaluated and revised, if necessary, as additional data become available throughout the study. The RI/FS will focus upon mining-related source materials and the transport of COPCs to surrounding media within the historically mined areas of the Site. The following potential areas will be investigated as part of the OU4 RI/FS:

• Mine and mill residues and smelter wastes (chat, fine tailings, and slag);

• Soil (transition zone, rural residential, and smelter-affected); • Surface water runoff and seepage from mill residues; and, • Shallow groundwater from wells in the Boone Aquifer utilized for

domestic purposes. This RI/FS WP is a scoping phase deliverable under the AOC. Future scoping phase documents to be submitted after EPA approval of this deliverable include the Sampling and Analysis Plan (SAP), which include a Field Sampling Plan (FSP) and a Quality Assurance Project Plan (QAPP); a Health and safety plan (HSP); and a Data Security Plan (DSP).


2

003044

1.2 Work Plan Organization The RI/FS WP is comprised of eight sections. Each section is listed below, along with a brief description of the section’s contents. Section 1 - Provides an introduction to the RI/FS WP, the objectives of the RI/FS, and a description of the RI/FS activities to be performed. Section 2 - Briefly describes the Site history and setting. A more detailed discussion of the Site background and setting is provided in the Data Gap Analysis Report (AATA, 2004b). Section 3 - Describes the initial evaluation of the Site, presents a generalized conceptual site model and identification of analytes, and describes the potential exposure migration pathways Section 4 - Explains the overall Work Plan rationale and describes the data quality objectives, data needs, and the technical approach for meeting each data need. Section 5 - Provides a description of each of the RI/FS tasks. Section 6 - Describes the overall project management strategy, procedures for amending the Work Plan, and a summary of the major RI/FS deliverables. Section 7 - Provides a schedule for implementing the RI/FS activities. Section 8 - Presents a list of references. A glossary of acronyms and abbreviations used throughout this document is listed in Appendix 1.


3

003045

2.0 Site Background and Setting This section provides historical information about zinc and lead mining at the Site, as well as a brief description of the physical setting of the Site including physiography, geology, hydrogeology, surface water, soils, climate, air quality, population, land use, and ecology. A more detailed description of the Site background and physical setting is provided in the DGA (AATA, 2004b).

2.1 Site History The first ore discoveries and earliest mining operations in Ottawa County, Oklahoma occurred in the vicinity of Peoria (6 miles east and 1 mile south of Lincolnville) in 1891 (Weidman, 1932). The next major ore discoveries occurred 1.5 miles northeast of Lincolnville near Quapaw in 1902, followed by discoveries in 1905 near Commerce. The real expansion of zinc and lead mining at the Site occurred after a major ore discovery in 1914 near the current site of Picher, Oklahoma. Following this discovery, there was a major expansion of mining in what became known as the Picher Mining Field (Picher Field) of Oklahoma and Kansas. By 1918, the Oklahoma section of the Picher Field was well defined by producing mines, with 230 mills built or under construction (Luza, 1986). Depletion of high-grade ores caused a marked decline in annual production after 1946, and depressed metal-market prices forced a cessation of most mining activities in 1958 (Brichta, 1960). The last record of significant production from Ottawa County occurred in 1970 (McKnight and Fischer, 1970).

2.2 Physical Setting The following subsections describe the physiography, geology, mineralization and ore deposits, hydrogeology, surface water, soils, climatology, air quality, population, and land use of the Site. Figure 2.1 shows the boundary of the Site for OU4. 2.2.1 Physiography The Site is situated within the Osage Plains section of the Central Lowland Province in northeastern Oklahoma. The Osage Plains is generally characterized by a low relief, rolling treeless prairie (Luza, 1986).


4

003046

North Miami

Tar Creek OU4Ottawa County, Oklahoma

2004I I Site Boundary

AATA INTERNATIONAL, INC.Fort Collins, Colorado, USA 0 § 0.25 ^ 0.5 ^ 1 Mile

003047

Elevations range from approximately 750 feet above mean sea level (MSL) in the vicinity of Miami to approximately 900 feet above MSL north and southwest of Lincolnville. The average elevation within the Site is approximately 830 feet above MSL. The ground surface rises slowly westward from Spring River, reaches a divide in the general vicinity of Quapaw and Lincolnville, and slopes very gently westward towards Elm Creek. The natural topography of the Site has been altered by mining activities. Numerous piles of mine and mill residues and collapsed structures associated with underground mine workings are present within the Site (Luza, 1986). 2.2.2 Geology The stratigraphic sequence within the Site consists of Paleozoic carbonate and clastic sedimentary rocks which overlie a Precambrian granitic and igneous basement complex. The surficial formations at the Site consist of Mississippian and Pennsylvanian units having a regional southwestward dip of approximately 20 to 30 feet per mile. The lower to middle Mississippian Boone Formation is the host rock for the lead and zinc ore deposits in the District. It consists primarily of limestone (sometimes oolitic), dolomite, and chert, along with lesser quantities of sandstone and shale. The Boone Formation is also an important water-bearing unit within northeastern Oklahoma, as discussed in Section 2.2.5. 2.2.3 Mineralization and Ore Deposits The principal zinc mineralization present within the ores of the District was zinc sulfide (ZnS), or sphalerite. Lead sulfide (PbS), or galena, was the primary lead mineralization within the ores. These minerals were contained in a matrix consisting of dolomite, limestone, or chert. Most of the zinc and lead mineralization that was the target of mining activities in the District was present within the Boone Formation. The Boone Formation is divided by Fowler and Lyden (1932) and Fowler (1942) into 16 beds, alphabetically denoted from 'B" (near the top of the Moccasin Bend Member) to "R" (in the Reed Spring Member). The "M" bed was the most significant ore-bearing unit in the District. Ruhl and others (1949) reported three principal types of ore accumulations in the District:

• Circle deposits, or irregular "runs," occur at or below the Pennsylvanian/Mississippian unconformity, in sinkholes, or along solution channels within limestone units. These deposits are typically the richest ore bodies in the District.


6

003048

• Sheet ground deposits that are found below the circle deposits and

occur in flat-lying to slightly undulating chert beds containing "sheets" of sphalerite and galena. These beds may be brecciated, and the sulfide ores may also be present as interstitial deposits within the chert. These are relatively low grade, large-tonnage ores.

• Simple or compound "runs", which occur between fairly well defined

fracture walls within the Reed Springs Member, below the sheet ground deposits. These deposits are typically richer but less aerially extensive than the overlying sheet ground deposits.

2.2.4 Mining-Related Materials A variety of mining-related materials were produced during mining operations conducted at the Site. The mining-related materials under consideration within the RI/FS are as follows:

• Development Rock (including overburden); • Chat; • Fine Tailings; and, • Smelter Waste.

Brief discussions of each of the material types listed above are presented in the following subsections. 2.2.4.1 Development Rock Development rock consists of boulder-sized materials containing little to no mineralization that were produced during mining operations. The term "development rock", for the purposes of the Tar Creek OU4 RI/FS, also includes overburden and waste rock. Overburden is unmineralized material extracted as part of surface mining operations. Waste rock is non-ore grade rock removed as part of the mining operations. 2.2.4.2 Chat Chat is the residue product derived from jigging operations in the milling of the mined ore and consists of material typically ranging from 1/4 to 5/8 inch in diameter. For the purposes of the RI/FS, the term "chat" also includes sand-sized materials, ranging from #20 to #65 mesh-size in diameter, which were produced during the milling process by the shaking table operations and was typically co-deposited with the jigging residues. Chat piles at the Site may also include particle sizes that are finer than #65 mesh-size (i.e., < 250 µm) from screened chat or discarded flotation tailings.


7

003049

2.2.4.3 Fine Tailings Fine tailings are materials passing the #65 to #200 mesh-size, which were generated during the milling operations. Fine tailings were produced as a result of screening of feed materials for gravity separation processes (jigging and tabling), during the froth-flotation process, and in conjunction with the washing and screening of chat to produce aggregates. Fine tailings were commonly deposited as a slurry in bermed areas or ponds, known as flotation, settling, or tailings ponds. All fine tailings are commonly called "flotation tailings", but technically only the residues from the froth-flotation process are flotation tailings. 2.2.4.4 Smelter Waste Smelter wastes are smelter-related materials and include slag, clinker and flux. Slag consists of the oxides of gangue materials produced by gravity separation from molten metals during smelting operations. Clinker is boiler residue composed of dust particles and insoluble organic residues created within the wood- or coal-fired steam plants that were typically used during the early history of mining activities in the District. Flux was used to remove iron during smelting operations and is typically composed largely of silica, with lesser quantities of alumina and lime. 2.2.5 Hydrogeology There are two principal aquifers in region: the Boone (Mississippian) and Roubidoux (Cambro-Ordovician) aquifers. The Boone Formation is the source of the shallow ground water and the Roubidoux Formation is the source of deeper ground water in the area. A sequence of limestone, shale, and dolomite strata, along with the upper portion of the Roubidoux formation form a semi-confining unit or aquitard separating the Boone aquifer from the Roubidoux aquifer. Within the Tri-State area, groundwater production from the Boone Formation for domestic purposes occurs where the depth to the aquifer is shallow and the groundwater is of acceptable quality (MacFarlane and Hathaway, 1987). Typical well yields within the shallow aquifer are 25 gallons per minute (gpm), with maximum anticipated well yields of 300 gpm in highly brecciated areas or in areas of extensive carbonate dissolution. The recharge area for the shallow aquifer is in the Ozark Mountains to the east, where these lithologic units crop out. Regionally, the water table within the shallow aquifer slopes in a generally westward to northwestward direction from these surficial exposures. Groundwater occurs under both confined and unconfined conditions within the Boone Formation in much of the Site.


8

003050

Groundwater within the shallow aquifer in Ottawa County is typically a calcium bicarbonate type and is hard to very hard (i.e., more than 121 milligrams per liter as calcium carbonate) (Marcher, et al, 1984). During mining activities, the groundwater table within the shallow aquifer was depressed in order to facilitate removal of ore. Upon cessation of mining activities, natural groundwater recharge occurred in conjunction with surface water inflow, resulting in flooding of the subterranean mine workings. It is estimated that the mines at Picher, Oklahoma contain 100,000 acre-feet of water (Playton, et al., 1980). By 1979, surface discharge of groundwater began as the mine workings became completely flooded. Reed, et al (1955) estimated annual discharge from the upper (shallow) aquifer to streams in the area of Ottawa County, Oklahoma at 10,220 million gallons per year (i.e., 43 ft3/sec). The lower Ordovician Roubidoux Formation consists largely of cherty dolomite and also contains, near its base, two to three sandstone layers that are 15 to 20 feet thick. Groundwater is produced from fractures and solution cavities within the dolomitic intervals as well as from porous zones within the sand-bearing strata. Significant local contributions to groundwater supply are also made by the Cambrian Eminence and Potosi Dolomites, with wells often screened across both Cambrian and Ordovician strata within the lower (deep) aquifer. Regionally, the water table within the lower aquifer slopes westward from recharge areas located to the east in the Ozarks. Recharge is variable, and occurs through sinkholes, by direct infiltration within the outcrop area, and by infiltration through streambeds (Harvey & Emmett, 1980). Wells tapping the Cambrian-Ordovician aquifer in northeastern Oklahoma are typically 1,000 to 1,300 feet deep. Withdrawal of groundwater from the Cambrian-Ordovician aquifer in Ottawa County was estimated at 4.3 million gallons per day in 1990, with individual well yields ranging from 100 to 1,000 gpm (Christenson, et al, 1990). Groundwater within the lower aquifer in Ottawa County is typically a calcium magnesium bicarbonate type and is moderately hand to hard (i.e., more than 61 mg/L as calcium carbonate) (Marcher, et al, 1984). Total dissolved solids concentrations range from approximately 350 mg/L to approximately 600 mg/L in Ottawa County (Marcher, et al, 1984). 2.2.6 Surface Water Surface waters that drain from the Site flow into two principal regional watersheds: the Neosho River and Spring River basins. Surface waters that drain the central and western portions of the Site include Tar, Lytle, Quapaw,


9

003051

Garrett and Elm Creeks, and associated tributary drainages. These streams flow south and drain into the Neosho River, about 1 mile southeast of Miami, Oklahoma. These streams are typically underlain by Pennsylvania shale and as such are subject to rapid runoff, flooding and intermittent flow. Surface drainages in the eastern portion of the Site flow into the Spring River. The surface geology of these drainages typically is Mississippian limestone, especially for drainages east of Highway 66. These small streams have intermittent flows and include Hockerville, Ontario and Beaver Creeks, and associated unnamed drainages in the eastern portion of the Site. Tar Creek drains the most intensively mined areas of the Site. The mining areas of the Picher Field, including the Treece, Kansas subsite, and the Oklahoma mining areas at Picher, Cardin, Hockerville, Century-Douthat, and Commerce all occur within the Tar Creek watershed. Historical mining activities have altered the drainage pattern of Tar Creek and its tributaries (Spruill, 1984; Luza, 1986). Tar Creek supplied water to the mills, received water pumped from mines, and was channelized and directed to keep water from flowing into mine workings. 2.2.7 Soils The soils present within the Tar Creek area are derived from the underlying Pennsylvanian sedimentary and Mississippian cherty carbonate rock formations, along with admixed Pleistocene and Holocene wind-deposited materials. Most of these soils are silty loams, which are composed primarily of silt, with lesser quantities of sand and clay. Chert and other rock fragments may also be present in significant quantities. The Taloka silt loam is the most common soil series present at the Site. Other locally prevalent soil series present include Dennis, Parsons, Choteau, Craig, Bates, and Newtonia. 2.2.8 Climatology and Air Quality The Site is characterized by a humid, continental climate. The average annual temperature is 57.5°F, calculated from the 1950 – 1980 period of record at the National Weather Service meteorological Station in Joplin, Missouri, located 20 miles northeast of the Site. The region experiences hot summers, with average temperatures of 80.1°F and 78.5°F in July and August, respectively. Temperatures are mild in the spring and autumn, which are characterized by warm days and cool nights. Winters are generally moderate, except when arctic air masses intrude. The average temperature in January, typically the coldest month of the year, is 32.6°F at Joplin. The average annual precipitation is approximately 42 inches. Most rainfall occurs in the spring and early fall, but 3-inch rainfall events may occur during summer thunderstorms. The driest period of the year occurs between


10

003052

November and February. Average annual snowfall is approximately 12 inches. Prevailing winds are southerly in all months except January and February, when northerly winds predominate. Average yearly wind speeds are 10 to 12 miles per hour (mph). Strong, gusty winds of 30 to 40 mph may be present in association with summer thunderstorms and winter cold fronts.

2.2.9 Population and Land -Use The U.S. Census Bureau estimates that the population of Ottawa County in 2001 was 33,046. Table 1 provides a list of the towns in Ottawa County and their populations.

Table 1. Ottawa County, Oklahoma Towns and Population, 2001* Town Population Afton 945 Cardin 175

Commerce 2,451 Fairland 904 Miami 12,760

N. Miami 448 Peoria 151 Picher 1,674

Quapaw 985 Wyandotte 361

Rural** 12,192 Total for Ottawa County 33,046

* Source: State of Oklahoma website: www.state.ok.us/osfdocs/cities.html** Source: Result of subtracting urban population from total population.

Most people own their own home in Ottawa County (73.9 percent). The median household income in 1999 was $27,507 (US Census Bureau, 2004). Land uses within the Site include agriculture, residential, light industry, commercial activities or businesses, and recreational uses, with agriculture being the dominant land use. As of 1986, approximately 2,900 acres of the area (approximately 11.2 percent) have mine and mill residues on the surface (Luza, 1986). Based on a map of the BIA's trust lands provided by the EPA, approximately 18 percent of the overall Site is owned by Native Americans.

Recreational land uses in Ottawa County include fishing, hunting, golf, softball, and soccer, and dirt bike riding. Southeast of the Site is Grand Lake, a swimming, boating, fishing, camping, and outdoor recreation area.


11

003053

http://www.state.ok.us/osfdocs/cities.html




2.2.10 Ecology Native vegetation of the Site is characterized by tall grass prairie dominated by bluestem, switchgrass and Indian grass on uplands, oak-elm woodlands in valleys, and cottonwood, sycamore and willow near stream channels. The Site has been heavily influenced by human activity, most notably agriculture and mining. Agricultural row crops and pastures have replaced most of the native prairie vegetation. The extensive mining that occurred at the Site resulted in large portions of the Site being covered with mine and mill residues. These areas range from a few hundred square feet to several acres in size (Luza, 1986). The chat piles are generally void of vegetation. Additionally, extensive areas once occupied by chat piles, but from which some of the chat has been removed, are present on the Site. These areas, defined as chat bases in the AOC, are sparsely to heavily vegetated, predominately by herbaceous plants (Brown and Root 1997). Major habitats that occur in the area include:

• cropland, including areas currently or recently cultivated; • old field/grassland, including non-cultivated areas, pastures, and grass

areas; • woodland including shrub thickets, windbreaks, and hardwood

bottomlands; • wetlands, including marshes, swamps, and vegetated areas adjacent to

streams, ponds and lakes, and, • disturbed areas, including urban areas, farmsteads, and mine and mill

residues. The wildlife species and habitats occurring at the Site are typical of the agriculturally-altered tall grass prairie environments. Wildlife habitats are principally associated with cropland margins and non-tillable areas with native floral representation remaining primarily in the riparian bottomlands and relic woodlots. Dames and Moore (1993) documented a total of 91 terrestrial wildlife species that were observed or documented by sign within the nearby Baxter Springs / Treece subsites as part of the RI field investigations. These 91 wildlife species included 62 species of avifauna, 16 species of mammals, and 13 species of herpetofauna (frogs and amphibians).

The creeks that drain the Site generally have intermittent flows, high sediment loads, and altered drainage patterns from channelization and diversions to keep the streams out of mine workings. The discharge of groundwater containing elevated concentrations of metals into Tar Creek has reduced the abundance and diversity of fish and macroinvertebrate taxa in Tar Creek.


12

003054

The small creeks typically contain forage fish such as darters, minnows and sunfish in areas with suitable habitat. In larger pools within the streams, largemouth bass and crappie may also be found. Ponds within the Site, including mill ponds, typically contain green sunfish, bluegill, largemouth bass, and other species.


13

003055

3.0 Initial Evaluations

3.1 Conceptual Site Models Conceptual site models for OU4 were developed by the EPA based on the types of mine and mill residues and smelter wastes present at the Site, and the sources, exposures, pathways and receptors. The human health and ecological receptor conceptual site models presented in Figures 3.1 and 3.2 are preliminary and may be modified during the development of the risk assessments. The conceptual site models show the possible sources of contaminants, illustrate possible pathways (or release mechanisms), transport and exposure media, potential exposure routes, and show receptors that may potentially be affected by exposure to contaminants.

3.2 Identification of Analytes The purpose of conducting chemical analysis on different types of media at the Site is to characterize the media of concern and to provide data for the ecological risk assessment (ERA) and human health risk assessment (HHRA). Based on results from previous RI/FS studies on mining-related sites in the District, cadmium, lead and zinc were identified to be the COPCs in the AOC for OU4. Therefore, cadmium, lead and zinc will be analyzed for all samples of every medium (chat, fine tailings, soil, water) at the Site to support site characterization, ERA and HHRA. Ten percent of the chat and fine tailing samples will be analyzed for all metals on EPA’s inorganic target analyte list (TAL), as shown in Table 2, to provide further information for the ERA and HHRA, as defined in the AOC.

For surface water and groundwater samples, several parameters in addition to the COPCs will be measured. Temperature, pH, specific conductance, alkalinity, dissolved oxygen, hardness, sulfate, iron, total suspended solids (TSS), total dissolved solids (TDS) and turbidity will be measured for surface water. For groundwater, pH, temperature, iron, sulfate, TDS, hardness, alkalinity and specific conductance will be measured.


14

003056

IngestionInhalation Dermal Contact

Trespasser

Chat Piles(including chatpile bases)

Worker

AirWind Inhalation Residential Child and

Adult.Subsistence Resident3

Surface WaterRunoff

IngestionInhalationDermal Contact

Mine and MillResidues(including millponds)

Soil Water Erosion

Residential Child IngestionSoil tracked into

indoor dust1Discharge/ WaterSeeps

Subsistence Residentand Resident Child

IngestionVegetation/fruitsMeat, game &Fowl

Smelter Waste SedimentSurface waterFish

PrivateWellWaterSupply

Ground water2 IngestionTap WaterLeaching

Sweat Lodge Inhalation Dermal Contact

Subsistence Resident

Figure 3.1. Conceptual Site Model Human Health Exposure Tar Creek Site OU4

Primay PotentialPrimary Release Transport Secondary Exposure Exposure PotentialSource Mechanism Medium Source Medium Route Receptor

1. Indoor dust will be collected from residential yards with a soil lead concentration equal or greater than the soillead screening level of 400 mg/kg.2. Contamination of ground water aquifers and public water supply is outside the scope of OU4 and is being addressed under OU13. Subsistence resident is used here to address tribal way of life that represent midrange exposure of a traditional tribal member wouldreceive.

Gkhoury C:\ursula\HHRA-conceptual site model for OU4-FINAL.wpd003057

IngestionInhalation Dermal Contact Direct Contact

Fauna &Flora

Chat Piles(including chatpile bases)

WindAir

Inhalation Fauna

Surface WaterRunoff

IngestionInhalationDermal ContactDirect Contact

Mine and MillResidues(including millponds)

Water Erosion Fauna & Flora Soil

Discharge/ WaterSeeps

IngestionVegetation/Prey Fauna

Smelter Waste

Sediment Fish & AquaticBiota

Surface water

LeachingFigure 3.2. Conceptual Site Model

Ecological Receptor Exposure

Tar Creek Site OU4

Primary PotentialPrimary Release Transport Secondary Exposure Exposure PotentialSource Mechanism Medium Source Medium Route Receptor

003058

Table 2. CLP Inorganic Target Analyte List Aluminum Antimony Arsenic Barium

Beryllium Cadmium Calcium

Chromium Cobalt Copper

Iron Lead

Magnesium Manganese

Mercury Nickel

Potassium Selenium

Silver Sodium

Thallium Vanadium

Zinc Note: (1) Based on the USEPA Contract Laboratory Program Statement of Work for Inorganics Analysis, Multi-Media, Multi-Concentration, Document Number ILMO 5.0 (3/99)


17

003059

4.0 Work Plan Rationale The RI/FS WP rationale is based on RI/FS Guidance (EPA,1988), “Guidance on Data Usability for Risk Assessments” (EPA, 1990), and Final Guidance for Data Usability in Risk Assessment, Parts A & B (EPA, 1992). The following subsections present the data needs and data quality objectives for the RI/FS, discuss the analytical quality levels and uses for various data types, present the Work Plan investigation approach, and explain the sampling strategies for characterizing the mine and mill residues, smelter wastes and relevant environmental media at the Site.

4.1 Data Needs and Data Quality Objectives Data needs and data quality objectives (DQOs) for the current RI/FS were discussed in detail in the DGA report (AATA, 2004b). The DQOs were established to identify the quality of the data necessary to support Site characterization, the risk assessments, and the remedy selection and evaluation process for the FS. The DQOs identify the amount of uncertainty in the data that is acceptable for each investigated medium. This uncertainty includes the variability of conditions within the media, sample variability, and sampling and analytical instrument error. The QAPP, which is part of the Sampling and Analysis Plan (SAP), will assure that the uncertainty of the data is within an acceptable range that will allow proper evaluation of the conditions at the Site. Table 3 summarizes the project data needs and objectives, the overall sampling strategy (or data source), and the DQOs for the OU4 RI/FS. The proposed analytes, laboratory analytical methods and method detection limits (MDL) for each medium are presented in Table 4.


18

003060

Table 3. Data Quality Objectives for OU4 RI/FS Minimum Data

Required Data Objectives Strategy Data Quality Objectives

Chat Piles, Chat Bases, Tailings Ponds and Smelter Wastes Location, areal extent, and volume of chat piles, screened chat piles, tailings ponds, waste rock, development rock, overburden, and smelter wastes.

Determine quantity and release mechanism of source material

Analysis of existing data from aerial imagery obtained in March 2004, surveys and topographic maps, field measurement and verification.

For accumulations larger than 20 feet in diameter, determine lateral dimensions via GPS within 1 to 2 feet. All chat accumulations with a height greater than 1 ft will be mapped and their volumes calculated.

Metal concentrations of chat, chat bases, fine tailings, and smelter wastes

Determine metal concentrations and variability of source areas.

Selective stratified random sampling

COPC concentrations via Level III protocol (i.e., analysis performed at lab using standard methods)

Particle size analysis of chat (Field)

Determine particle size fractions to distinguish between screened chat, remilled chat, and chat

Collect and sieve samples, from all major chat piles (i.e., >85,000 yd3 in volume) to determine the origin of the material

Determine particle size distribution using selected sizes of standard sieves

Bulk density and pH of chat

Determine density and pH of representative chat piles

Bulk density and pH will be measured for every chat pile to be sampled

Determine bulk density and pH via Level II protocol in the field

Location of channels that drain accumulated mine residues

Locate mine residue drainage channels for COPC and sediment transport

Aerial photos; field verification

Accuracy to 1-2 feet

Affected Soils and Background Soils COPC concentration in background soils, transition zone (TZ) soils, rural residential yard soils and smelter-affected soils

Determine COPC concentration and variability in this potentially affected media

Surface and subsurface sampling at selected locations

Determine COPC concentrations via Level III protocol (i.e., analysis performed at lab using standard methods)

Surface Water COPC concentrations, iron, dissolved oxygen, flow, temperature, pH, TSS, TDS, sulfate, turbidity, alkalinity, hardness and conductivity in runoff / seepage from chat piles

Determine concentration of COPCs and TSS from chat pile runoff / seepage during dry and wet weather periods

Chat pile runoff/seepage sampling and analysis; data from previous investigations

Determine COPC concentrations, TSS, alkalinity, and hardness via Level III protocol (i.e., analysis performed at lab using standard methods); determine precipitation, flow, conductivity, temperature, pH and turbidity measurements in the field via Level II protocol


19

003061

Minimum Data Required

Data Objectives Strategy Data Quality Objectives

COPC and iron concentrations, flow, temperature, pH, TSS, TDS, sulfate, turbidity, alkalinity, hardness, dissolved oxygen and conductivity in streams receiving drainage from chat piles

Determine COPC loadings in streams receiving drainage from mine and mill residues during dry and wet periods to allow for an evaluation of COPC loading sources.

Sampling and analysis of COPCs in streams upstream and downstream of mine and mill residue accumulations during dry and wet weather periods

Determine COPC, iron concentrations, TSS, alkalinity, and conductivity via Level III protocol (i.e., analysis performed at lab using standard methods); determine precipitation, temperature, hardness, pH, dissolved oxygen and turbidity measurements in the field via Level II protocol

Groundwater COPC, iron and sulfate concentrations, TDS, hardness, alkalinity, pH, temperature, conductivity, in shallow aquifer water wells used for domestic purposes

Determine concentration of COPCs in well water from the shallow aquifer

Identify domestic water wells in the shallow aquifer in OU4; sample and analysis of all identified domestic wells;

Determine COPC concentrations via Level III protocol (i.e., analysis performed at lab using standard methods or EPA protocol)

Ecology Identification, location and aerial extent of vegetation communities/ wildlife habitat

Develop a current vegetation/ wildlife habitat map for the RI

Analysis of March 2004 aerial imagery and LandSat imagery supervised classification with field verification.

Vegetation mapping accuracy to within 100 feet.

Characterization of plant and animal communities; Plant species composition and vegetation cover

Identification of ecological receptors that could be exposed to COPCs from the Site; Determine plant species composition and cover for TZ soils and each of the major vegetation communities for the RI

Literature review, aerial imagery and mapping analysis; Vegetation field sampling (point and line intercept and quadrat sampling methodologies at 10 locations)

Plant sampling methodology according to standard protocols; transect accuracy to within 1 to 2 feet

State and/or Federal protected plants and animals

Identify State and/or Federal protected species that occur at the Site

Literature review on habitat requirements of protected species that might occur

Determine likelihood of protected species presence based on existing habitat

COPC in sediments, water, benthos and plants from mill ponds

Allow for the determination of risks to waterfowl that use mill ponds in the Ecological Risk Assessment

Analyze COPCs in sediments, water, benthos and plant tissue in a representative number of mill ponds

Determine COPC concentrations via Level III protocol (i.e., analysis performed at lab using standard methods).


20

003062

Table 4. Parameters, analytical methods and detection limits (MDL) for

laboratories Surface Materials* Surface Water

Parameter EPA Methods MDL (mg/kg) Parameter EPA Methods MDL (mg/L)Aluminum M200.7/6010 3 Cadmium M200.7/6010 0.003 Antimony M200/7000 0.2 Iron M200.7/6010 0.01 Arsenic M200/7000 0.1 Lead M200.8/6020 0.0001 Barium M200.7/6010 0.3 Zinc M200.7/6010 0.01 Beryllium M200.7/6010 0.2 Sulfate M300.0 0.5 Cadmium M200.7/6010 0.3 TDS M160.1 10 Calcium M200.7/6010 20 TSS M160.2 5 Chromium M200.7/6010 1 Hardness SM2340B 1 Cobalt M200.7/6010 1 Groundwater Copper M200.7/6010 1 Cadmium M200.7/6010 0.003 Iron M200.7/6010 1 Lead M200.8/6020 0.0001 Lead M200.7/6010 4 Zinc M200.7/6010 0.01 Magnesium M200.7/6010 20 Iron M200.7/6010 0.01 Manganese M200.7/6010 0.5 Sulfate M300.0 0.5 Mercury M200.8/6020 0.005 TDS M160.1 10 Nickel M200.7/6010 1 Hardness SM2340B 1 Potassium M200.7/6010 30 Selenium M200.7/6010 4 Silver M200.7/6010 0.5 Sodium M200.7/6010 30 Vanadium M200.7/6010 0.5 Zinc M200.7/6010 1 pH (Field) M9045C 0.1 Moisture Content SM 209D 1%

Biota Cadmium M200.8/6020 0.01 Lead M200.8/6020 0.01 Zinc M200.8/6020 0.2

* Surface materials include chat, flotation tailings, smelter wastes and soils.

4.2 Work Plan Approach The general approach and specific tasks outlined in Section 5.0 of this RI/FS WP were developed based upon a review of the AOC, SOW for the Tar Creek OU4, the DGA report (AATA, 2004b), the Conceptual Site Models, and the preliminary Remedial Action Objectives (RAOs). The Site Characterization phase for OU4 consists of five major components: 1) evaluation and use of existing data; 2) field investigations; 3) laboratory analysis of field samples; 4) risk assessment; and 5) data management. The first component, evaluation and use of existing data, has already been performed in the DGA report


21

003063

(AATA, 2004b). Component 4, risk assessment, will be performed by the EPA.

4.3 Sampling Strategies The scope of work of this RI/FS was negotiated for the AOC and the overall sampling strategies for OU4 were defined in the SOW in the AOC. Studies were conducted during OU1 on the effects of acid mine discharges on surface water, groundwater and sediments at the Site. Residential yard and high access area soils were addressed in OU2. The OU4 RI/FS will focus on mine and mill residues and smelter wastes deposited as part of former mining-related operations and affected soils adjacent to these sources. The media of concern for OU4 are as follows:

• Mine and mill residues (chat, chat base, and fine tailings) and smelter wastes;

• Soils including transition zone (TZ) soil, rural residential yard soil and smelter-affected soil;

• Surface water runoff, seepage and sediment transport from existing mill residues accumulations; and,

• Groundwater quality of rural wells in the shallow Boone Aquifer that are used for domestic purposes.

Preliminary analysis of volumetric calculation results based on the 2004 aerial imagery indicate that the total volume of 42 major chat piles at the Site (i.e., those with greater than 85,000 yards in volume) accounted for 95% of the total chat volume at the Site. The US COE’s 1999 volumetric study showed similar results where 34 major piles (i.e., those greater than 100,000 cubic yards) accounted for 95% of the total chat volume at the Site. Therefore, the 42 major chat piles at the Site will be considered for OU4 field investigation and sampling. 4.3.1 Mapping of Surface Features As part of the OU4 RI, surface features will be mapped, which include distribution of mine and mill residues (historical and contemporaneous), drainages, mine shafts, subsidence features, TZ soils, vegetation, property ownership, roads and railways. Current surface features will be first delineated with recent (March 2004) acquired aerial photographs followed by on-Site field confirmation. Historical footprints of mine and mill residues (including chat base) will be delineated with analysis of available historical aerial photographs and confirmed in the field.


22

003064

All surface features mapped will be incorporated into the project GIS. 4.3.2 Sampling of COPC Sources A brief discussion of the sampling strategy for the media to be sampled for the RI/FS is provided in the following subsections. Detailed discussions on sampling rationales, location, frequency, field procedures, documentation, QA/QC and analytical procedures will be presented in the SAP. 4.3.2.1 Mine and Mill Residues and Smelter Wastes The concentrations of COPC in mine and mill residues and smelter wastes will be investigated using a stratified random sampling strategy. Sampling locations will be randomly selected by overlaying a grid over the aerial imagery of the accumulation of materials and randomly selecting grid nodes. For sampling and analysis, priority will be given to those areas which have (a) not been previously studied, (b) are in close proximity to OU4 residents, (c) are in close proximity to OU2 residents, and (d) are in the flood plains of Tar Creek, Lytle Creek, Beaver Creek, or Elm Creek. Each type of mill residue or smelter waste will be sampled using specific protocols that will be defined in the SAP. The sampling strategy is designed to provide data for use in site characterization, feasibility studies, and baseline risk assessments. To be useable, the data must attain a certain level of confidence, as measured by statistical performance criteria. 4.3.2.2 Soils – Transition Zone, Rural Residential, and Smelter-

Affected TZ soils will be sampled to investigate the lateral and vertical extent of COPC migration. As defined in the AOC, TZ soils consist of the soil area from the edge of the residue pile where metal concentrations are elevated out to the point where metal concentrations are below levels potentially causing risks to human health or the environment. TZ soil sampling will be used to define a practical outer limit for the COPC-affected soils. Sampling will be conducted upwind and downwind of selected isolated chat piles (tailings ponds) along a transect from the edge of each selected pile. Isolated chat piles or tailings ponds are necessary to avoid overlapping of multiple COPC sources (especially nearby piles and tailings ponds). Residential soils will be collected in front and back yards at all properties within the Site that were not previously sampled during OU2. Smelter-affected soils will be sampled upwind and downwind from the former location of the Ottawa smelter near Hockerville. This information will


23

003065

determine the surface metals deposition patterns in soils surrounding the Ottawa smelter. 4.3.2.3 Surface water Surface water issues to be investigated for OU4 include COPC loading to the streams at the Site from chat pile seepage and runoff. COPC and sediment loading to nearby drainages will be investigated by (1) collecting data on the runoff and seepage from two representative chat piles, and (2) determining the relative contribution of COPC loading from mine and mill residues via surface water runoff in Tar Creek, Lytle Creek, Beaver Creek and Elm Creek. This information will be compared to a similar study conducted by OWRB (1983) over 20 years ago. Locations of potential runoff from mining-related sources into each of the four creeks draining the Site will be identified based on air imagery and finalized during field reconnaissance. Water quality samples will be collected from each of the four creeks upstream and downstream of these mining-related runoff areas. In order to determine the relative contribution of COPC and sediment loadings from the chat piles compared with surface water and groundwater COPC contributions, wet and dry weather samples will be collected at these locations. 4.3.2.4 Groundwater The OU4 RI/FS effort on groundwater will include an inventory of rural wells in the shallow aquifer (Boone Aquifer) that are used for domestic purposes. All wells identified that are used for domestic purpose will be sampled and analyzed for COPCs. The concentrations of COPCs in each sampled well will be compared to MCL drinking water standards to evaluate the potential health risk associated with this drinking water supply.


24

003066

5.0 RI/FS Tasks The major tasks and the deliverables to be completed during the RI/FS are shown in Table 5. Generally, a RI/FS is accomplished via the following major tasks:

• Scoping Phase Planning Documents • Site Reconnaissance • Site Investigation with Sampling and Analysis • Human Health Risk Assessment • Ecological Risk Assessments • RI Report • Treatability Studies (if necessary) • Feasibility Study with Remedial Alternatives

Each of these tasks is described in detail in the following sections.

Table 5. Major RI/FS Tasks for Tar Creek OU4 TASK 1 - SCOPING PHASE PLANNING DOCUMENTS

1.1 Deliverables: Scoping Phase Work Plan (submitted) Data Gap Analysis Report (submitted) RI/FS Work Plan Sampling and Analysis Plan

Health and Safety Plan Data Security Plan

TASK 2 – SITE RECONNAISSANCE AND SITE INVESTIGATION

2.1 Investigate Site physical and chemical characteristics 2.2 Document and map surface features 2.3 Document and map Mine and Mill Residues and Smelter Wastes (area and

volume) 2.4 Conduct aerial imagery analysis 2.5 Classify residue accumulations 2.6 Sampling and analysis Mine and Mill Residues and Smelter Wastes Soils – TZ, residential and smelter-affected Surface water Groundwater Ecology (flora and fauna) 2.7 Deliverables: Preliminary Site Characterization Summary (with maps, aerial photographs, and all sampling results)

TASK 3 - HUMAN HEALTH RISK ASSESSMENT (HHRA) (Prepared by EPA)

3.1 Evaluate existing District data 3.2 Evaluate all new Site data


25

003067

3.3 Prepare toxicity assessment 3.4 Prepare exposure assessment, exposure pathways 3.5 Develop risk assessment 3.6 Prepare HHRA Report 3.7 Deliverables:

Draft and Final HHRA Reports TASK 4 - ECOLOGICAL RISK ASSESSMENT (ERA) (Prepared by EPA)

4.1 Assess toxicity of residues 4.2 Hazard characterization/ecological effects 4.3 Development of the measurement endpoint 4.4 Evaluation of data 4.5 Prepare ERA Report 4.6 Deliverables:

Draft and Final ERA Reports TASK 5 – RI REPORT 5.1 Incorporate Site Characterization Report and EPA Risk Assessment

5.2 Prepare RI Report 5.3 Deliverables:

Draft and Final RI Reports TASK 6 - TREATABILITY STUDIES (If Necessary)

6.1 Prepare Candidate Technologies Memorandum 6.2 Prepare treatability study work plan 6.3 Conduct treatability studies 6.4 Prepare Treatability Studies Evaluation Report 6.5 Deliverables:

Candidate Technologies Memorandum Draft and Final Treatability Studies Reports TASK 7- FEASIBILITY STUDY

7.1 Refine Remedial Action Objectives (RAO) 7.2 Develop Preliminary list of applicable or relevant and appropriate

requirements (ARARs) and Information To-Be-Considered 7.3 Develop screen remedial alternatives

7.4 Conduct detailed analysis of remedial alternatives 7.5 Prepare FS Report 7.6 Deliverables:

Revised remedial action objectives memorandum Listing of ARARs and To-Be-Considered memorandum Development and Screening of Remedial Alternatives Report Detailed analysis of alternatives memorandum Draft and Final FS Reports


26

003068

5.1 Scoping Phase Planning Documents The Scoping Phase Planning Documents include the Scoping Phase Work Plan, the DGA report, the RI/FS WP, the SAP (which contains the FSP and QAPP) the HSP, and the DSP. The Scoping Phase Work Plan (AATA, 2004a) and the DGA report (AATA, 2004b) have been completed. The RI/FS WP is addressed in this document. The FSP and DSP will be submitted to the EPA after approval of the RI/FS WP.

5.2 Site Reconnaissance A site reconnaissance will be performed before the initiation of formal Site investigations. The purpose of this Site reconnaissance is to:

• Conduct a general classification of mine and mill residues and smelter

wastes; • Conduct field mapping and ground-truthing of the GIS data in

conjunction with the aerial imagery; • Identify chat, chat base, flotation tailings, tailings ponds, smelter waste

and TZ soil sampling locations; • Identify chat pile seepage / runoff sampling locations; • Determining upstream and downstream sampling locations for

evaluation of COPC contributions from mill residues to surface waters; and,

• Measure conductivity and pH in the field from chat pile seepages. Data on the location, area, and volume of current and former mine and mill residues and smelter wastes will be collected according to the categories of development rock (waste rock or overburden), chat, chat bases (with or without vegetation), screened chat, mill-related ponds, and smelter wastes. This data collection will use a two-step process: (1) aerial imagery analysis including volumetric analysis; (2) field verification and ground-truth during the Site reconnaissance. While development rocks, chat, fine tailings and smelter wastes can be easily identified through visual examination; field sieving will be required to differentiate chat from screened chat. All major chat piles (i.e., those over 85,000 yd3in volume) will be sieved during Site investigation in the field to not only differentiate chat from screened chat, but also to obtain particle size distribution data that can be used in prioritizing remedial actions during the FS (AATA, 2004b). Three sieves sized 3/8 inch (9.5 mm), #4 (0.187 inch or 4.75 mm) and # 40 (0.0165 inch or 425 µm), will be used to conduct the size distribution analysis in the field, which will generate 4 size groups of chat:

• Group I: + 3/8 inch;


27

003069

• Group II: - 3/8 to + #4; • Group III: - #4 to + #40; and, • Group IV: - #40.

Generally, chat will contain particles of all the four Groups. Re-milled chat will have Groups II, II and IV particles but missing Group I particles. The discarded portion from commercial screening of chat (commercial residues) is expected to contain only Group III and Group IV particles. Samples to be sieved will be collected using ATSM’s bulk sampling techniques from a freshly cut, exposed portion of the chat pile being sampled. Detailed sampling procedure will be presented in the SAP. As required by the AOC, the location, area and volume of development rock will be mapped but not chemically sampled as it has been shown not to be a significant source (if any) of COPC. Because of the composition of the parent material (Pennsylvanian Shale), it is expected that the particle sizes of the surface (0-1 inch) TZ soil at the Site are less than 250 µm and will not require screening to obtain this size fraction for the HHRA. To confirm this, representative samples of the surface TZ soils will be collected during Site reconnaissance for particle size analysis. The samples will be screened in the field with a #40 sieve to remove any debris such as vegetation roots or rock chips (if any) and then sent to the laboratory where further particle size analysis will be conducted with a #60 sieve (250 µm mesh-size). The identification of sampling locations during the reconnaissance will be conducted with representatives from EPA, ODEQ and the Quapaw Tribe.

5.3 Site Investigation Formal Site investigation will start after the Site reconnaissance. This section discusses the objective and tasks to be completed during the Site investigation. Data on the physical and chemical characteristics of OU4 will be compiled or collected to define distribution and concentration of COPC and COPC transport pathways, and will provide sufficient engineering data for development and screening of remedial action alternatives for OU4. Information will be collected on chat piles, chat bases, fine tailings, smelter wastes, transition zone soils, rural residential soils, smelter affected soils, surface water transport from chat piles, shallow groundwater for domestic use, and biota (flora and fauna). A geographic information system (GIS) will be used to organize, analyze, plot, and display key data sets. This effort will use the ArcView GIS system as a platform for database management, research, analysis, and reporting.


28

003070

Preparation for field activities will include procurement of subcontractors, coordination with analytical laboratories, confirmation of Site access, and mobilization of personnel and equipment. Prior to beginning the field activities, a Site coordination and health and safety meeting will be conducted to advise the field team of Site-specific procedures such as Site access and departure procedures, and health and safety issues including personal protective equipment, decontamination procedures, and who to contact in the event of an emergency, as well as an overall review of the Site-specific Health and Safety Plan. AATA will ensure that the field methods, sampling procedures and chain of custody records are consistent with EPA’s “A Compendium of Superfund Field Operations Methods” (Two Volumes, U.S. EPA, Office of Emergency and Remedial Response, EPA/540/P-87/001a, August 1987; Office of Solid Waste Emergency Response Directive No. 9355.0-14). A Preliminary Site Characterization Summary report will be submitted to EPA after the Site investigations. 5.3.1 Surface Feature Mapping and Aerial Imagery Analysis Mine and mill residues at the Site will be delineated as part of the Site reconnaissance. Other surface features to be mapped during Site investigation include, but are not limited to, mine shafts, subsidence features, fencing, property ownership and utility lines, roadways, railways, drainage ditches, leachate springs, surface water bodies, flood plains, vegetative communities, residences, commercial buildings, and other man-made structures. Historical data on surface features will also be collected by examining earlier aerial photographs and other available sources. Existing OU4 surface features will be described using 2004 aerial imagery combined with ground-truth confirmation during fieldwork at the Site. Surface features will be geo-referenced and entered into the project GIS system. 5.3.2 Sampling and Analysis As stated in the DGA, when selecting sample sites for chat, chat bases, fine tailings and TZ soils, priorities were given to those areas which a) have not been studied previously; b) are in close proximity to OU4 residents; c) are in close proximity to residential area, and d) are in direct drainage to Tar Creek, Lytle Creek, Beaver Creek or Elm Creek. Proposed sampling locations will be presented in the SAP and finalized during Site reconnaissance. 5.3.2.1 Chat Bulk chat and screened chat will be collected for chemical analysis. In addition, chat sampled at 0 to 1 inch depth and sieved to <250 µm (herein


29

003071

surface fine chat) will be analyzed. The following numbers of samples will be collected as defined in the SOW of the AOC:

• bulk chat – 120 samples (from 15 chat piles; 8 samples per pile); • surface fine chat – 16 samples (from 8 piles; 2 samples per pile); and, • screened chat – 40 samples (from 5 screened chat piles; 8 samples per

pile). All chat samples will be analyzed for COPC (Cd, Pb and Zn). To support the HHRA, ten percent of the bulk chat and screened chat and all of the surface fine chat will be analyzed for the TAL metals as listed in Table 4. Samples will be collected based on a modified method from ASTM D-75 “Standard Practice for Sampling Aggregates” (ASTM, 2003a). The method in ASTM D-75 was defined for one composite sample with 3 subsamples to characterize an aggregate pile; while eight composite samples (each with 5 subsamples) will be collected to characterize a chat pile. Sample mixing and splitting methods will be based on ASTM C-702, “Standard Practice for Reducing Samples of Aggregate to Testing Size” (ASTM, 2003b). At each sample location, a 5-part composite sample will be collected from the center and corners of a 10-foot square. Each of the 5 subsamples will be collected by digging a small pit of two feet long, two feet wide and one foot deep (using a shovel) and taking one shovel (approximately a quarter of a gallon) of chat from the innermost part (bottom center) of the pit. All 5 subsamples will be placed on a clean heavy plastic sheet. The sample will be mixed by alternatively pulling one corner of the sheet over the opposite corner a minimum of 10 times. A conical heap will then be formed and split in four similar parts by dividing with a spatula in a cross-shaped pattern. Two opposite quarters are removed and the remaining quarters will be re-mixed. This cone and quarter method will be repeated three times until about 20 oz of sample is obtained. The sample will then be put in a double Ziploc plastic bag with proper labeling and shipped to the laboratory for analysis. 5.3.2.2 Chat Base A chat base is the area that was previously occupied by a chat pile that was subsequently cleared. Since chat removal at the Site was done for commercial purposes, a thin layer of chat was normally left in place. Chat bases can be vegetated in some cases. Chat bases at the Site will be mapped by examining recent and historical aerial photographs followed by on-Site confirmation during field investigations.


30

003072

A total of 16 bulk chat base samples will be sampled from 4 chat base sites (4 from each site). Field sieving and depth determination of chat bases will be conducted at each chat base selected for sampling. All chat base samples will be analyzed for Cd, Pb and Zn. Chat base sampling will be conducted using the same methods as chat sampling described above. If the chat base is less than 1 foot thick, samples will be taken from the center portion of the chat profile excluding a minimum of 1 inch at top and the bottom. If the chat base is less than 2 inches thick, no sample will be taken and an alternative site will be selected. 5.3.2.3 Fine Tailings Areas identified as fine tailings accumulations (mill-related ponds) will be mapped out using the March 2004 imagery and followed by subsequent field confirmation. Drilling/excavations will be conducted at selected locations for subsurface sampling for volume estimation. A total of 100 samples from 10 fine tailings ponds will be collected and analyzed for COPC. Ten percent of the fine tailings samples will be analyzed for the TAL list of metals (see Table 4) for the HHRA. It is expected that particle sizes of all fine tailings at the Site are less than 250 µm in diameter. All fine tailings samples will be depth integrated as required by the AOC. Subsurface sampling of fine tailings will be conducted with a stainless steel shovel, hand-operated auger or by hollow-stem drilling following ASTM D-4700 sampling procedures, depending on the depth of the fine tailings accumulations. The depth-integrated sample will be collected by evenly scooping through the entire depth interval of the fine tailings accumulation. If needed, the sample will be mixed and split following the procedures outlined in ASTM C-702 (ASTM, 2003). 5.3.2.4 Smelter Wastes One former smelter location is known at the Site, i.e., the Ottawa Smelter near Hockerville. Visual inspections of the former smelter location will be conducted, noting the nature and type of smelter wastes present, particle size distributions of any wastes identified, and the locations of these materials. Five composite grab samples of near-field smelter waste will be collected from identified waste accumulations. These five samples will be analyzed for their COPC and antimony concentrations. Because of scattered nature and limited amount of smelter wastes at the site, opportunistic sampling of identified smelter waste will be conducted. Surface


31

003073

vegetation (if any), rocks and other debris will be removed before sampling. A stainless steel shovel or scoop will be used to collect 10 to 15 oz of the sample. The sample will be placed in a double Ziploc plastic bag for shipment to the laboratory. 5.3.2.5 Soils - Background, Transition Zone, Rural Residential, and

Smelter-affected Soil sampling will be conducted following established EPA and ASTM protocols (EPA, 1996b, 2000 & 2003; ASTM, 1998). Background soils will be sampled at selected locations within OU4. A total of seven samples of 0 - 6 inch depth will be sampled at locations removed from immediate vicinity of mine and mill waste accumulations. Four samples will be collected from areas where surface soils were derived from the Pennsylvanian Shale. Three samples will be collected from areas where surface soils were derived from the Mississippian Limestone. Specific sampling locations will be determined during the Site reconnaissance with consultation of the stakeholders. All background soil samples will be analyzed for TAL metals as listed in Table 2. TZ soils will be investigated to assess the transport of metals from mill residues to adjoining soils. Based on TZ soil studies performed within other mining-related sites in the District, a width of 300-foot from the edge of chat piles or tailings ponds was adopted for the sampling at the Site. TZ soil samples will be collected next to 5 isolated chat piles or tailings ponds. Samples will be collected along a transect at 0, 5, 10, 20, 40, 70, 120, 200 and 300 feet intervals from both upwind and downwind sides of selected chat piles or tailings ponds. At each sampling location, 4 samples will be collected at depths of 0-1 inch, 6 inches, 12 inches and 24 inches. A total of 360 TZ soil samples will be collected and these samples will be analyzed sequentially outward from the pile until COPC concentrations are less than 2 times the background concentration as defined in the AOC. TZ soil samples will be collected following the procedures below:

• Clear surface vegetation (if any), rocks and other debris not designated for sampling from the sampling point;

• Dig a sample pit of one foot long, one foot wide and two foot deep using a stainless steel shovel;

• Measure and mark the pit wall at designated depth (i.e., 0-1 inches, 6 inches, 12 inches and 24 inches);

• Scoop the pit walls (using a stainless steel scoop) evenly at each designated depth to obtain 10 – 15 oz of sample;

• Place the sample in a double Ziploc plastic bag that is properly labeled and ship the sample to the laboratory.


32

003074

Residences in OU4 that were not sampled as part of OU2 will be sampled for this RI/FS. All samples will be analyzed for COPC concentrations. In addition, ten percent of the yard soil samples (the surface 0-1 inch portion) will be sieved and analyzed only the < 250µm portion for COPC concentrations. Five-part composite samples will be collected at identified residential yards following EPA approved protocols presented in “Superfund Lead-Contaminated Residential Sites Handbook” (EPA, 2003). Surface (0-6 inch) and subsurface (6-12 inch and 12-18 inch) yard soil sample will be collected using a stainless steel shovel following similar procedures as for TZ soil sampling described above. If needed, the composite sample will be mixed and split with same methods described in chat sampling section. If soil lead concentrations are greater than the soil lead screening level of 400 mg/kg in a residential yard, then indoor dust samples will be taken and analyzed for lead, and the potential sources of lead in the yard soil and house dust will be evaluated. Sampling of indoor dust will be conducted following EPA procedures defined in Chapter C of the “Residential Sampling for Lead: Protocols for Dust and Soil Sampling” (EPA, 1995). For smelter-affected soils, up to 52 surface soil samples (0-6 inches) at distances from 0-5,000 feet will be taken in the predominant upwind and downwind directions at 200-foot intervals from the former smelter. The actual number of samples will depend on the distance at which chat or other mill residues are encountered. Analysis of the smelter-affected soil samples for COPC will be done sequentially starting nearest the smelter location and continue until the COPC levels are equal to or less than twice the background concentrations of COPC in soil as defined in the AOC. Five-part composite samples will also be collected for smelter-affected soils from the center and the four corners of a 10-feet by 10-feet square at each sampling site. Surface (0-6 inch) sample will be collected using a stainless steel shovel. If needed, the composite sample will be mixed and split with same methods described in the chat sampling section. 5.3.2.6 Surface Water Runoff / Seepage Investigation The OU4 RI/FS will determine the metal loadings from chat pile runoff/seepage during dry and wet weather events. Two representative chat pile locations will be selected for the runoff/seepage study during the Site Reconnaissance. A hydrological monitoring station will be installed at the selected runoff site for each of the two piles. The station will include a pressure transducer (installed in an open channel, weir or flume), data logger, flow meter, automatic flow-activated water quality sampler, and tipping bucket rain gauge. A rating curve of the relationship between stage vrs.


33

003075

discharge will be developed from the pressure transducer and flow meter data. The sampler will be programmed to collect water samples only when the water level in the channel reaches a specified height that indicates that the runoff event is significant. The automatic flow-activated water quality sampler will be used to collect surface water samples during the wet event. Automatic stormwater samplers will be programmed to collect two types of water samples during a runoff event from the chat piles. A first-flush sample will be collected automatically within the first 60 minutes of a runoff event. The first-flush sample potentially contains the highest concentration of contaminants during a runoff event. The second type of water sample collected will be a flow-weighted composite sample. In this type of sample, water samples are collected periodically throughout the storm hydrograph and composited to represent the average concentration of contaminants during a runoff event. Field measurements of pH, turbidity, alkalinity, dissolved oxygen, conductivity and temperature will be obtained from the samples collected. The first flush and flow-weighted composite samples will be analyzed for COPCs (total and dissolved fractions), iron, sulfate, total suspended solids, total dissolved solids, and hardness in the laboratory. Sediment transport off the chat piles will be measured by determining the total suspended sediment and bedload sediment fractions. Total suspended sediment will be sampled from the automatic composite sampler. A Helly-Smith Bedload Sampler or equivalent device will be used to measure the amount of bedload sediments during a runoff event. All water and sediment samples will be analyzed for COPCs. Chat pile seepage samples during dry weather conditions will be collected manually. A minimum of 7 days of consecutive dry weather (no measurable rainfall) would be observed before dry weather sampling would occur. One set of water samples will be collected by carefully immersing a laboratory-supplied clean sample container into the upper portion of the water column. For sample aliquots requiring preservatives, the containers with preservatives will be filled by pouring water into them from immersed sample containers not containing preservatives. Dry weather condition samples will be analyzed for the same analytes as described for the wet weather event except that bedload sediment will not be measured. Bedload sediment transport from chat piles is assumed to be negligible under dry weather conditions. Chat pile seepage discharge will be measured from a weir or flume at the time of sample collection.


34

003076

Metals Loading Investigation An investigation will be conducted to compare surface water transport versus groundwater transport of COPCs to nearby surface waters. Chat pile runoff locations in Tar, Lytle, Beaver and Elm Creeks will be determined during the Site Reconnaissance. Sampling stations will be established upstream and downstream of those runoff locations. Dry weather samples will be taken at both upstream and downstream locations on each of the four creeks (eight locations) to determine COPC concentrations and loadings during dry conditions when groundwater is assumed to supply nearly all of the flow of the creeks. At the time of dry weather sampling, field measurements of pH, turbidity, dissolved oxygen and temperature will be made using modern water quality field instruments. Analyses to be performed in the laboratory include COPCs, (total and dissolved fractions), iron, sulfate, total dissolved solids, conductivity, hardness, alkalinity and total suspended solids. Stream discharge at the 8 locations will be measured through the velocity-area method according to USGS protocols (Rantz et al. 1982) during a dry period and wet weather event. Stream discharge will be measured in the stream by wading, or from a bridge, or by boat depending on site location and streamflows. If the sampling site occurs where the USGS already has an operating stream gage, then gaging at this site will not be necessary. Surface water sampling during wet weather runoff conditions will occur at the same eight locations used for dry weather sampling using composite, flow proportional sampling, to determine COPCs concentrations and loadings under runoff conditions. The composite, flow proportional sampling will be collected either with an automatic sampler as described for the chat pile seepage and runoff study or manually. If wet weather event water samples are collected manually, then a Van Dorn water bottle or similar device will be used to collect the water samples at various stream stages during the runoff event. Four water samples will be collected at four different stages of the hydrograph and later composited into one composited sample at each sampling location. A field team will sample the upstream and downstream locations of the creek during a particular runoff event. An on-Site precipitation gauge will record the amount of rainfall that fell during the runoff event that was sampled for surface water quality on each of the four creeks. The wet weather event samples will be analyzed for the same analytes as described for the dry weather samples. A total of 20 surface water samples will be collected during the surface water investigation. The results of the surface water runoff sampling will be used to determine the relative contribution of COPC from surface water seepage /


35

003077

runoff as compared to groundwater contributions. This will be done using mass balance equations comparing the dry period sampling results to the wet weather sampling results. 5.3.2.7 Groundwater An updated inventory of rural domestic wells in the shallow aquifer will be conducted by contacting the homeowners of all rural residences to determine their potable water supply source. Any identified shallow well in OU4 that is being used for domestic purposes will be sampled in accordance with standard EPA protocols involving clean techniques (EPA, 1996). Groundwater samples will be collected prior to any home treatment system. A first run sample and a flushed water sample will be collected at each identified shallow well. The following procedures will be followed in the collection of groundwater samples from domestic shallow wells at the Site:

• Disconnect water treatment system, if any; • Turn on the tap and collect the first run sample using a clean container

and measure pH, specific conductance, alkalinity and temperature; • For the flushed water sample, allow the water to run for at least 5

minutes prior to sample collection; • Collect the flushed water sample using a clean container and measure

pH, specific conductance, alkalinity and temperature; • Fill necessary sample bottles and complete labels (sample bottles and

labels will be provided by selected laboratory); • Place the sample bottles in a cooler at 4˚C for shipment to the

laboratory. Groundwater samples collected will be analyzed for COPCs, sulfate, total dissolved solids, iron and hardness in the laboratory. 5.3.2.8 Biota The biological investigations for the OU4 RI/FS will delineate the vegetation community types and wildlife habitats present at the Site and will collect data to evaluate the risk to waterfowl associated with the use of fine tailings ponds. Vegetation characterization The vegetation sampling locations and community types will be selected during the Site reconnaissance with agency consultation. Characterization of the major plant communities will be performed by sampling vegetation using a point and line intercept and quadrat sampling techniques. A total of 10 representative locations representing the major plant community habitats in OU4 will be sampled by point and line intercept methods. At each representative location, a transect will be established in each of the four


36

003078

cardinal directions. A GPS unit will be used to record the location of the transects. The transects will be 25 m in length at each sampling location. At one-meter intervals along the transect, quantitative measurements will be taken for cover, canopy closure, composition, and woody plant density. Ground cover at each transect point will be measured using point-intercept methodology. Intercepts with vegetation (by species or life form) litter, rock, or bare soil will be determined with the aid of an optically based point frame that uses cross hairs and parallax-free optics. Plant species, total cover (percent) and relative cover, density and frequency will be calculated for each transect at each location. Canopy cover will be estimated visually. Woody plant density (exclusive of vines) will be determined by direct counts of plants within large rectangular quadrats or belts sized at 6m by 30m. A belt will be established along each transect where woody plants are present. Because many species exhibit multiple stems, individual plants rooted in the belt will be recorded by species. Tree species also will be recorded by diameter at breast height (DBH) class. Qualitative information also will be noted while conducting the characterization inventories, such as land management practices, anomalies in the communities and activities by man in the area. Observations of Potential Phytotoxicity in the Field Identification of any obvious phytotoxic conditions in the transition zones, chat bases, and tailings ponds will be noted during the field reconnaissance and vegetation sampling. This will be accomplished by recording any visual trace metal toxicity symptoms observed in plants during the plant sampling program. These symptoms may include red veins in leaves from Cd, stunted foliage from Pb, or commonly interveinal chlorosis resulting from inhibition of Fe uptake caused by excessive Cu and / or Zn (Kabata-Pendias, 2001). EPA will conduct an independent evaluation of phytotoxicity as part of the risk assessment. Mapping of Vegetation Communities and Wildlife Habitat A supervised classification of a recent LandSat 7 Enhanced Thematic Mapper (TM) data will be performed for the Site to map vegetation community types and wildlife habitats. Land use and plant communities provide distinctive spectral signatures in Landsat enhanced TM imagery that are useful in delineating different vegetation types and land use. PCI Image Works and ArcView GIS software will be used to perform the vegetation classification. The automated classification will be generated using the following input data layers in the database:

• 30 meter multispectral Landsat 7 bands 1 through 5 and 7;


37

003079

• 15 meter panchromatic Landsat 7 band 8; and, • 3 x 3 mean texture measure results from 30-meter band 1.

Visual interpretation of the LandSat imagery and newly acquired aerial imagery will be utilized to define the various vegetation / land use classes. A Maximum Likelihood Classifier Algorithm will be employed to analyze the spectral and textural input information to define the vegetation / land use classes. The following classifications are anticipated.

• Woodlands (upland forest, floodplain forest, riparian forest, shrub thickets);

• Grasslands (remnant tall grass prairies, pastures); • Wetlands; • Croplands (including currently and recently cultivated); • Disturbed areas (chat piles, chat bases, tailings ponds, transition zone

soils, urban areas, roads); and • Water (creeks, ponds).

The March 2004 aerial imagery of the Site has a 6” pixel resolution and will be used to refine the LandSat classification and boundaries of the community types. The final vegetation / land use classes will also be field verified by inspections during other investigations. Fine Tailings Ponds To provide the data necessary to evaluate the potential risks associated with waterfowl usage of tailings ponds in the ERA, an investigation will be conducted to determine if COPCs are being taken up into the tissues of plants and benthic macroinvertebrates in tailings ponds potentially utilized by waterfowl. Three flooded tailings ponds will be selected for surface water, sediment, aquatic macrophyte and benthic macroinvertebrate sampling to evaluate risks to waterfowl from these potential COPC sources. The tailings ponds will be selected during the Site reconnaissance with agency consultation. Selection criteria for the ponds will include the availability of water year-round, size, depth, aquatic habitat quality, the existence of an established aquatic plant community, accessibility, and safety. A coordinate grid system will be superimposed on the aerial imagery of the selected mill ponds to select potential pond sampling locations for macrophytes, invertebrates, sediment and water samples. Within the grids that contain macrophyte beds, three 1m2 plots will be randomly selected for collocated aquatic macrophytes, sediment, benthic macroinvertebrates and water samples.


38

003080

Aquatic macrophytes will be collected from 3 separate locations in each pond and composited into one sample for COPC analysis. The stems and leaves of aquatic macrophyte specimens (unwashed) will be collected from a boat with a rake from selected 1m2 locations. The species of the plants collected for analysis will be recorded. Enough plant material will be collected to comprise approximately 20 grams wet weight. Macrophyte samples will be placed in a stainless steel bowl, cut up with stainless steel scissors, and thoroughly mixed. Samples of the mixed plant tissues will be placed in gallon size plastic ziplocked bags and placed in a cooler on ice. Plant tissue samples will be sent to the analytical lab for analysis. The laboratory will dry and weigh the plant tissue to determine dry weight of the samples. The plant tissue will then be analyzed for COPC concentrations. The results will be reported as µg of lead, cadmium or zinc per gram of dry weight of plant tissue. Benthic macroinvertebrates will be sampled in the three representative tailings ponds from a boat using an Ekman dredge and will be analyzed for COPC content. Sampling results will be standardized by units of effort expended during sample collection (number of dredge samples). A minimum of three dredge samples will be collected from each pond and composited. The composited benthic sample will be sieved in the field through a 0.5 mm mesh screen. The benthos retained on the screen will be transferred to a labeled, plastic container, placed on ice in a cooler at 4ºC, and shipped to the analytical laboratory for analysis. The laboratory will determine the dry weight of the samples and analyze the tissues for COPCs. A minimum of 5 grams of wet weight of benthos will be required for COPC analysis. The results will be reported as µg of cadmium, lead, or zinc per gram of dry weight benthic macroinvertebrate tissue. Details on sampling specifics (e.g., locations, species selection, etc.) for aquatic macrophytes and benthic macroinverbrates will be made in consultation with the EPA, ODEQ, DOI and Quapaw Tribe stakeholders. Three replicate surface water and sediment samples will also be collected. These surface water samples will be analyzed for pH, total and dissolved lead, cadmium, zinc and iron, sulfate, specific conductance, dissolved oxygen, temperature, alkalinity, TSS, TDS and hardness. The sediment samples will be analyzed for COPCs (total cadmium, lead and zinc). Surface water samples from the ponds will be collected utilizing a Van Dorn water sampler or similar device. Surficial sediment samples will be collected with an Ekman dredge.

5.4 Preliminary Site Characterization Summary Upon the conclusion of site investigations and the completion of all laboratory analytical work, a Preliminary Site Characterization Summary (PSCS) report will be prepared and submitted to EPA.


39

003081

The PSCS will present a brief review on the following:

• Description of Site investigation activities; • Results of field sampling and analysis; • Sampling locations of all media investigated (with maps or aerial

photographs); • Location and characteristics of surface features (with maps and aerial

photographs); • Location of OU4 rural residences where yard soils were sampled; • Location and boundary of development rocks, chat, chat base, mill-

related ponds, and smelter affected-soils (with maps or aerial photographs);

• COPC concentrations at all sampling sites (with maps or aerial photographs); and,

• Results of volumetric calculations of chat remaining at the Site.

5.5 Human Health Risk Assessments EPA will develop a HHRA for OU4. EPA will perform a statistical evaluation of the existing data along with the data that will be collected for the RI/FS investigation. EPA, with collaboration of the Quapaw Tribe, will develop a risk assessment specific to the way of life for a typical tribal member.

5.6 Ecological Risk Assessment (ERA) EPA will conduct a conservative ERA based on existing and OU4 media data that will include assessment of direct contact toxicity and assessment of food chain risks. The terrestrial ecology of the Site will be characterized including, but not limited to, the flora and fauna in the area for use in the environmental characterization for EPA’s ERA.

5.7 RI Report The RI Report will be prepared following EPA approval of the final Preliminary Site Characterization Summary report and after EPA’s completion of the HHRA and ERA. The RI Report will describe the field investigation work and the results of that work, define the sources of COPC contamination, determine the nature and extent of contamination at OU4, and evaluate the fate and transport of COPC. The RI Report will follow the format described in Table 3-13 of the RI/FS Guidance and will include text that covers all the topics listed in the table. Section 6 of the RI Report


40

003082

(Baseline Risk Assessment) will be provided by EPA. The RI Report will include a summary on the results of all the sampling and analysis, all the data collection and compilation, the results of the QA/QC reviews, and all other information gathering described in the AOC.

5.8 Treatability Studies The following subsections describe the approach that will be taken to identify the need for treatability studies, present a plan for implementing the treatability studies, and describe the evaluation of the results of any treatability studies undertaken in order to identify remedial actions for the Site source materials and affected media. 5.8.1 Candidate Technologies Report During the Site investigation task and as part of the identification and screening of potentially applicable remedial technologies, the need for treatability studies will be evaluated. The early identification of specific remedial technologies applicable to the Site will help ensure that data needed to evaluate them is available and allow determinations as to the need for treatability studies. A Candidate Technologies Report will be prepared to describe candidate technologies for potential use in the remedial action for OU4. The screening of technologies for potential treatability testing will be conducted in accordance with the National Contingency Plan (NCP; 40 CFR Part 300) and the guidance document “Technology Screening Guide for Treatment of CERCLA Soils and Sludges”, EPA/540/2-8/004, September, 1988. The screening will include the following:

• Identification of COPC; • Selection of effective or potentially effective technologies; • Review of the technologies to determine expected performance; • Determination of pretreatment and residual management needs; and, • Identification of data needs and requirements for evaluation of

technologies. Concurrent with the identification of candidate technologies and based on work undertaken at other sites in the District, a literature survey will be conducted to acquire information from vendors, case studies, other CERCLA site studies, and available literature on known treatment techniques. The information gathered will be used to determine the following for each screened technology:

• Potential uses or restrictions of the technology;


41

003083

• Critical testing parameters; • Specific equipment needs for testing; • Commercial applicability, implementability and availability (i.e.,

beneficial uses, including evaluation of commercial uses of chat based on its site-specific chemical and physical characteristics);

• Any short-term and/or long-term environmental impacts; • Removal efficiencies or other performance capabilities; • Potential for and/or methods to prevent or reduce recontamination of

remediated areas; • Operation and maintenance requirements; and, • Relative technology costs.

Treatability studies will be recommended for those technologies that appear to be viable but for which inadequate data are available because the technology has not been tested on materials sufficiently similar to those at the Site. To identify potential treatability study needs, the following areas will be evaluated, at a minimum:

• Beneficial uses of surficial mill tailings, including commercial reuse (e.g., evaluation of samples of washed chat from commercial chat washing operations, evaluation of chat usage in concrete, for road building as an aggregate in asphalt or for road base material, either used separately or mixed with an additive such as fly ash);

• Methods to prevent or reduce the potential for recontamination of

areas previously remediated; and,

• Restoration of contaminated property to beneficial use (e.g., evaluation of the suitability of using former chat pile areas for agricultural land use including phytotoxicity evaluation of target species).

Potential technologies that may require treatability studies, as well as the process for identifying such technologies, will be documented in the Candidate Technologies Report. This report will outline the data utilized from other sites in the District, the technologies screened and a summary of the screening results. Additional data requirements will be outlined to the extent possible for planning purposes. The Candidate Technical Report will also include the results of the literature survey of candidate technologies. 5.8.2 Treatability Study Work Plan If EPA determines that practical candidate technologies have not been sufficiently demonstrated in the Candidate Technologies Report, or if EPA determines that candidate technologies cannot be adequately evaluated for OU4 on the basis of available information, EPA will require treatability studies for candidate technologies. Following that determination, a


42

003084

Treatability Study Work Plan will be submitted to EPA (with copies to ODEQ and Quapaw Tribe). The Treatability Study Work Plan will describe the work needed and a schedule for its completion. Elements of the Treatability Study Work Plan would include, but not be limited to the following topics:

• Data that must be gathered; • Type of treatability test (bench vs. pilot); • Site background; • Remedial technologies to be tested; • Test objectives; • Test location(s) and apparatus; • Experimental procedures; • Treatability conditions to be tested; • Measurements of performance; • Data quality objectives (DQOs); • Analytical methods; • Data management and analysis; • Health and safety procedures; and, • Residual waste management.

If pilot-scale treatability testing is to be performed, the Treatability Study Work Plan will describe pilot plant installation and start-up, pilot plant operation and maintenance procedures, operating conditions to be tested, a sampling plan to determine pilot plant performance. If testing is to be performed off-Site, the Treatability Study Work Plan will describe permitting requirements and how compliance with the requirements will be achieved. If EPA determines that the QAPP or FSP prepared for the RI is not adequate for defining the activities to be performed during any treatability studies, then a separate, written Treatability Study SAP will be prepared and submitted to EPA (with copies to ODEQ and the Quapaw Tribe) for review and approval. Similarly, if EPA determines the HSP for the RI is inadequate for treatability testing, a separate, written Treatability Study HSP will be prepared and submitted to EPA (with copies to ODEQ, and the Quapaw Tribe) for review. 5.8.3 Treatability Study Evaluation Report Upon completion of treatability studies, if necessary, the results will be analyzed and interpreted for use during the FS. All treatability studies conducted will be summarized in a Treatability Study Report and submitted to EPA (with copies to ODEQ and the Quapaw Tribe) for review and approval. The report will evaluate each candidate technology for its effectiveness, implementability, cost of implementation, and a comparison of actual study results versus predicted results. The report will also provide an evaluation of


43

003085

the full-scale application of each candidate technology, including without limitation a sensitivity analysis identifying the key parameters affecting full-scale operation.

5.9 Feasibility Study (FS) 5.9.1 Objectives of the FS Based upon information developed during the RI, a FS will be conducted to develop and evaluate remedial action objectives and candidate remedial alternatives. The FS will be conducted in accordance with the appropriate sections of the EPA RI/FS Guidance, “Guidance for Conducting Remedial Investigations and Feasibility Studies under CERCLA”, EPA/54O/G-89/004, October 1988). The major objective of the FS is to identify the most technically feasible and cost-effective remedial action alternative or combination of alternatives to deal with the mine and mill residues and smelter wastes at the Site based on detailed assessments and comparative evaluations. 5.9.2 Overview of the FS Activities The FS process can be viewed as occurring in two primary steps: 1) development and screening of alternatives, and 2) detailed analysis of the screened alternatives. This process is intended to reduce the number of potential remedial actions for the Site to the most appropriate and applicable methods currently available. The FS will evaluate various types of remedial actions and institutional controls as a means to prevent exposure to mine and mill residues, smelter wastes and affected media. The FS process will include a detailed review of all available Site data. In addition, the following tasks will be completed:

• Review and revision of the potential Remedial Action Objectives (RAOs), General Response Actions (GRAs), and Remedial Action Alternatives (RAAs);

• Identification and revision of potential chemical-specific and action-

specific Applicable or Relevant and Appropriate Requirements (ARARs) and To-Be-Considered (TBC) information;

• Review and screening of technologies for addressing mine and mill

residues and smelter wastes and affected media;


44

003086

• Development and screening of remedial alternatives appropriate for the Site;

• Detailed analysis of alternatives consisting of a nine-criteria analysis

and a comparative analysis in accordance with the revised NCP; and

• Preparation of the FS Report. 5.9.3 Development and Screening of Remedial Alternatives As the initial step in developing remedial alternatives, a review of candidate technologies will be performed to identify those technologies that may be applicable for addressing the RAOs. The specific tasks that will be performed during this initial screening include:

• Determine the volume of each medium of concern and the conditions of each medium, if any, requiring remedial action;

• Identify general response actions (GRAs) for areas of concern;

• Evaluate technologies previously considered for other sites in the

District;

• Eliminate from future consideration technologies and specific process options that are not applicable for the Site based on an evaluation of effectiveness, implementability, and cost;

• Define the technology for process options that would serve as a key

component or ancillary component to a remedial action. Key components are those that would establish a significant general approach for addressing a particular source area or managing one or more pathways of migration. Ancillary components are those which contribute to implementation of the overall approach or which are used to control incidental problems which result from implementation of another technology such as fugitive dust control during soil removal and its potential for recontamination of remediated areas;

• Identify chemical-specific and action-specific ARARs;

• Formulate alternatives that may be protective of human health and the

environment from available technologies for Site media and pathways; and,

• Screen alternatives based on short and long-term effectiveness,

implementability, and cost.


45

003087

The AOC identified the following general requirements for the development of remedial alternatives to be considered in the FS:

• Identify one or more alternatives to control source materials with little or no treatment, but which protect human health and the environment primarily by preventing or controlling exposure to hazardous substances or COPC (lead, cadmium, zinc), through engineering controls (containment), and as necessary, institutional controls (deed restrictions or easements) to protect human health and the environment and to ensure continued effectiveness of the response action. This potential alternative will include commercial use of chat as part of the alternative description.

• Develop a range of alternatives to control source materials in which a

principal element is treatment that reduces toxicity, mobility, or volume of hazardous substances or COPC. If EPA determines it appropriate, the range of alternatives will include an alternative that removes or destroys hazardous substances or COPC to the maximum extent feasible, eliminating or minimizing the need for long-term management.

• Develop other alternatives for control of source materials that, at a

minimum, treat the principal threats posed by OU4, but which vary the degree of treatment employed and the quantities and characteristics of the treatment residuals and untreated residues that must be managed.

• Develop one or more innovative treatment technologies for further

consideration if, as determined by EPA, those treatment technologies offer the potential for comparable or superior performance or implementability; fewer or lesser adverse impacts than other available approaches; or lower costs for similar levels of performance than demonstrated treatment technologies.

The screening of alternatives will follow the guidance in 40 CFR Part 300.430(e)(7)(i) through (iii). During the development and screening of alternatives, technical memoranda will be prepared to document the process and to obtain EPA review comments on the process. After the development and screening process, the Development and Screening of Remedial Alternatives Report will be submitted to EPA (with copies to ODEQ and the Quapaw Tribe) for review and approval. The report will include the results and reasoning employed in screening alternatives and identifying the specific ARARs for each of the alternatives that remained after screening.


46

003088

5.9.4 FS Report The FS Report analysis will identify pertinent advisories, criteria, or guidance documents. The analysis will include an assessment of the individual alternatives against each of the seven evaluation criteria described in 40 CFR Part 300.430(a)(9)(iii)(A) through (G). The analysis also will provide a comparative analysis that focuses on the relative performance of each alternative against each of the seven evaluation criteria. The analysis will reflect the scope and complexity of OU4 problems and the alternatives being evaluated, and it will consider the relative significance of the factors within each of the criteria. Development of the FS Report will follow the FS Report format described in Table 6-5 of the RI/FS Guidance (EPA 1988). The FS Report will include text that addresses all the topics listed in Table 6-5 of the Guidance. At the conclusion of the detailed FS analysis, a FS report will be prepared documenting the feasibility studies as outlined above. The FS report will provide the basis for the final remedy selection by EPA. The FS report will be submitted as a draft for review and approval prior to the final report being released to the public.


47

003089

6.0 Project Management and Organization The following sections explain how implementation of the OU4 RI/FS will be managed, provide procedures for amending the project work plans and data reporting, and provide a summary of the RI/FS deliverables.

6.1 Project Management Project management activities shall include:

• Coordinating RI/FS plans and schedules; • Monitoring the involvement and performance of RI/FS project staff

and subcontractors; • Monitoring project performance and providing day-to-day guidance of

the work, including preparing revisions of the schedules and manpower requirements, as well as participating in the discussion of technical issues;

• Submitting monthly progress reports to EPA; and, • Coordinating the quality control oversight with the Site activities.

The project management elements indicated in the “Guidance for Conducting Remedial Investigations and Feasibility Studies under CERCLA” (Interim Final, October 1988) are discussed below. 6.1.1 Project Team Several task managers and coordinators will manage the different project components and coordinate the work. These positions are:

• Lead Agency (EPA) • Respondents Project Coordinator • RI/FS Project Manager • Project Liaisons • Remedial Investigation Task Manager • Feasibility Study Task Manager • Site Data Manager • Quality Assurance Project Officer • Health & Safety Officer • Field Investigation Coordinators


48

003090

Figure 6.1 depicts, by discipline, an organizational chart for the RI/FS project. The EPA Remedial Project Manager is responsible for managing the project for EPA, coordinating preparation of the risk assessments and interfacing with the Respondents Project Coordinator. The Respondents Project Coordinator is responsible for coordinating all project activities of the RI/FS working team, as well as communications among the RI/FS Project Manager, the EPA Remedial Project Manager (RPM) and the Respondents. The RI/FS Project Manager is responsible for managing the day-to-day operations of the OU4 RI/FS. 6.1.2 Project Coordination Among Agencies, Potential

Responsible Parties, and the Lead Contractor Coordination among the parties directly involved in the RI/FS will be ensured by the EPA RPM and the Respondents Project Coordinator through the following functions:

• Liaison with the support agencies and Respondents; • Coordination of activities, technical guidance and quality control with

the support agencies, and Respondents; • Review of monthly progress reports and other project deliverables; and • Review and monitoring of schedules.

Project communications will be documented using written correspondence, technical and project memoranda, e-mails, telephone conversation records, minutes of meetings, and addenda and revisions to the project plans. The RPM will periodically convene meetings in Dallas, Texas or at other designated locations. 6.1.3 Schedule Management The project schedule is presented in Section 7.0. Tracking the project schedule will be a primary responsibility of the RI/FS Project Manager. Methods that will be used to ensure that the work stays on schedule include:

• Subdividing major tasks identified in the project schedule into smaller tasks and preparation of milestone chart(s);

• Calculating manpower and equipment requirements based on tasks to be completed at each stage of the project;

• Recording and tracking actual versus expected progress; • Managing resources to avoid schedule conflicts and minimize

mobilization/demobilization time; and • Reporting schedule status to Respondents and EPA.


49

003091

Project LiaisonsFederal, State &Tribal Agencies

US EPA Region VIRemedial ProjectManager (RPM)

RespondentsProject Coordinator

EPARisk Assessment Team

Blue Tee Corp.Gold Fields Mining Corp.

RI/FSProject Manager

Quality AssuranceProject Officer Review Committee &

Project Consultants

Remedial InvestigationTask Manager

Site Data Manager

Analytical Laboratories

Feasibility StudyTask Manager

Remedial InvestigationField Coordinators

Field Studies Team

Health & SafetyProject Officer

Treatability Studies

Project ProfessionalStaff (Geologist, Soil

Scientist, etc.)

Project Engineers

Project CISManagement

Figure 6.1 Project Organization Chart Other Project andSupport Staff

003092

6.1.4 Training Documentation Measures taken to ensure that project staff members are trained with regard to requirements for the work will include the following:

• Staff health and safety training will be conducted and recorded in accordance with a Site-specific HSP;

• Sampling and analysis operations and QA/QC procedures will be specified in the SAP;

• General quality assurance procedures will be provided in the QAPP; • The Project Manager and task managers will verify that the assigned

staff have been trained and are familiar with the above planning documents; and,

• The Project Quality Assurance Officer will verify that all staff members have been trained adequately.

6.1.5 Data Management A technical information management system including a secured project web site and a project geographic information system (GIS) will be used for OU4 RI/FS data management. The project web site contains all available project-related information, including previous RI/FS work conducted at the Site and within the District. All of these existing materials were digitized and available for on-line review or download. The project web site is facilitated with a fully searchable database, with which references can be easily located for download or on-line review. The Project GIS System has been established with ArcView GIS 8.3. At its completion, the Project GIS system will include the following:

• Landsat imagery (Landsat Thematic Mapper data fused with 15 m panchromatic);

• Aerial photography (historical and contemporaneous); • Property ownership including tribally controlled properties; • Distribution of mine and mill residues (historical and

contemporaneous); • Soils, including transition zone soils; • Drainages; • Sampling locations (residues, rural yards, water, soil, flora, fauna,

etc.); • COPC concentration levels; • Vegetation (supervised classification); • Threatened and endangered plant species distribution and potential

habitats; • Predicted limits of TZ soils;


51

003093

• Site-specific attribute data; and, • Ground-level photodocumentation;

The Project GIS System will be used for data maintenance and analysis as a single repository for all map and attribute information associated with the Site. This system will provide all of the benefits of computerization when managing large amounts of spatial and technical information. The Project GIS System will be used to create Site maps, generate contours of COPC concentrations, delineate buffer zones (such as transition zone soil) boundaries, as well as calculate areas of COPC sources and affected media. This system will associate data to a coordinate location on a site map (i.e., making sampling sites as data points where key site information, such as Site description, levels of COPC and digital photography can be readily viewed). In addition, spatial analysis tools available in the geographic information system will aid in the characterization of the Site. The project web site together with the project GIS systems will not only provide the ability to store and update records, but will also standardize databases and record keeping, improve accuracy of calculations and analysis, improve record security, provide quick search and retrieval of data, and provide better auditing display capabilities. 6.1.6 Quality Assurance Quality assurance (QA) comprises all those planned and systematic actions necessary to provide adequate confidence that a product or service will satisfy given needs. The project QA program will be developed in detail in the QAPP and included within the SAP. The elements of quality assurance apply to all phases of the study through the development of final documents. The QA program will be organized and implemented by the Project QA officer who reports to the Project Manager. The QA officer will participate in project planning, prepare the QAPP, coordinate review of deliverables, audit performance and recommend corrective action as needed.

6.2 Procedures for Work Plan/SAP Amendments This Work Plan is intended to be a flexible document that will allow for modifications through a regular evaluation of existing and newly acquired findings throughout the RI/FS process. Work Plan amendments will require prior written approval from the EPA. Work Plan amendments may be additional tasks not originally identified in the Work Plan as well as changes, or deletions of tasks.


52

003094

The Work Plan is designed to be a general guidance document that defines the sampling strategy and approach but does not specify sampling locations and procedures. The SAP will provide the detailed information necessary to complete the tasks identified in the Work Plan. It is anticipated that most procedural changes that may be needed during the RI/FS will be defined in amendments to the SAP. The Work Plan Revision Form, attached as Appendix 2, will be used throughout the project to communicate and document revisions identified to complete the project. 6.2.1 Post-Approval Amendments - Additional Work Other work, in addition to the tasks completed under the RI/FS Work Plan, may be required if the EPA RPM or the Respondents Project Coordinator determines that, without such additional work, the RI/FS would be incomplete. If, at any time during the RI/FS process, a need for additional work is identified, a memorandum documenting the need for such work will be submitted to the EPA Remedial Project Manager within ten days of identification of the additional work needed. 6.2.2 Post-Approval Amendments - Other Reasons Revisions to the Work Plan for reasons other than additional work needs, such as Site conditions and/or incoming Site data, may prompt a need for changes in sampling strategies, task elements, or other aspects of the Work Plan. These changes to the Work Plan will be handled as described below. 6.2.2.1 Field Changes Field changes, such as modifications to sampling techniques, locations, quantities or analytical methods, generally will be addressed only in amendments to the SAP. Where such amendments contradict information in the Work Plan, the SAP amendments will be considered binding. 6.2.2.2 Minor Modifications Minor changes are those that do not require immediate execution as the field changes often do, but are not significant enough to halt work pending EPA RPM approval. Examples of minor modifications include changes of subcontractors and changes in the RI/FS schedule as a function of the actual time required for EPA review and approval of submittals. With the exception of minor schedule changes, the EPA will be notified in writing of the intent to make modifications using the form provided in Appendix 2. Any changes in subcontractors will also be submitted in writing for approval. Schedule changes that occur as a result of a variation in the time required for document review and approvals will be reported in monthly progress reports. Requests for schedule changes due to modifications will be submitted separately and


53

003095

are subject to EPA approval. Decisions to halt field activities because of emergency conditions will be made by personnel performing those activities. Activities not affected by an emergency will not be suspended. 6.2.2.3 Major Modifications Major revisions to the Work Plan are those that represent substantive modifications to the investigation approach or strategy, or represent changes that will materially alter the nature and amount of data or information to be obtained during the RI/FS. Major amendments will be requested in writing and will not be executed until approval is received in writing. The reasons for the change and the time for EPA review may necessitate a halt in the work related to the affected part of the Work Plan. Thus, the Work Plan amendments request may be accompanied by a request for an amended schedule that will provide an extension of time at least equal to that required for agency review of the proposed amendment, regardless of whether the amendment is accepted or rejected. The ultimate decision to halt work will be made by the EPA for major modifications.

6.3 Summary of RI/FS Deliverables The following sections outline the deliverables anticipated for OU4 RI/FS. 6.3.1 Monthly Progress Reports A monthly progress report detailing activities performed during the previous calendar month’s reporting period and a description of actions scheduled for the following calendar month’s reporting period will be submitted on or before the 20th day of the month. Note that if the 20th day of the month falls on a weekend or Federal holiday, then the due date will be the following Federal workday. The monthly progress reports will be submitted to EPA Remedial Project Manager. 6.3.2 Project Deliverables and Review Conferences Major deliverable documents of the Tar Creek OU4 RI/FS and their anticipated completion schedule are given in Table 6. Review conferences on the draft of all major deliverables will be scheduled and conducted prior to submittal of the final version. These conferences will be scheduled within the last 3-4 days of the reviewing period permitted for each submittal. EPA (and cooperating agencies and organizations on the OU4 RI/FS) will furnish written review comments on the data and reports submitted at the various investigation milestones. These comments will be discussed at a meeting scheduled after submittal of major draft document


54

003096

deliverables to the EPA, ODEQ, Quapaw Tribe and other affiliated agencies. The objective of the meeting is to discuss the comments and come to agreement on the resolution to all comments. The consensus of edits will be incorporated before submittal of the final report document.


55

003097

Table 6. Major deliverables and milestones of the OU4 RI/FS

ACTION TIMING 1. Effective Date – Administrative Order On Consent (Order)

Initiation of the RI/FS Process

2. Submit Project Coordinator to EPA Submitted 3. Identify Contractor to EPA Submitted 4. Identify Quality Assurance Official Submitted 5. Provide Proof of Insurance to EPA Submitted 6. EPA provides Preliminary Remedial Action Objectives (also see Item 29)

Received on January 9, 2004.

7. Submit Draft Scoping Phase Work Plan to EPA Submitted on January 20, 2004 8. Meeting on Draft Scoping Phase Work Plan Held in Dallas, TX on February 10, 2004 9. Submit Final Scoping Phase Work Plan to EPA Submitted on March 9, 2004 and approved on March 22, 2004 10. Submit Draft Data Gap Analysis Report Submitted on June 20, 2004 11. Submit Conceptual OU4 Model Received from EPA on January 9, 2004 12. Meeting with EPA on Draft Data Gap Report and Conceptual OU4 Model

Scheduled on August 24-26, 2004

13. Submit Final Data Gap Analysis Report Within 30 days of the meeting on the Draft Data Gap Analysis Report

14. Submit Draft RI/FS Work Plan to EPA Within 60 days of the meeting on Data Gap Analysis Report 15. Meeting with EPA on the Draft RI/FS Work Plan Within 14 days of receipt of notice of meeting from EPA 16. Submit Final RI/FS Work Plan to EPA Within 30 days of meeting on Draft RI/FS Work Plan 17. Submit Draft Sampling and Analysis Plan (SAP) – to include Field Sampling Plan, Quality Assurance Project Plan, and Health and Safety Plan to EPA

Within 45 days of EPA Approval of the Final RI/FS Work Plan

18. Meeting with EPA on the Draft SAP Within 14 days of receipt of notice of meeting from EPA 19. Submit Final SAP to EPA Within 30 days of meeting on Draft SAP 20. Submit Draft Data Security Plan to EPA Within 30 days of EPA Approval of the Final RI/FS Work

Plan 21. Submit Final Data Security Plan to EPA Within 30 days of receipt of EPA’s comments on Draft Data

Security Plan 22. Commence Field Studies Within 45 days of Approval of Final SAP, QAPP, and H&SP 23. Notice of Field Activities 15 days prior to initiation of field activities and 10 days prior

to completion of field activities 24. Access Acquisition to Field Sites Within 30 days of identifying need to access field sites 25. Submit Draft Preliminary Site Characterization Summary to EPA

Within 90 days of receipt of the final laboratory sample results from field investigations

26. Meeting with EPA on the Draft Preliminary Site Characterization Summary

Within 14 days of receipt of notice of meeting from EPA

27. Submit Final Preliminary Site Characterization Summary to EPA

Within 30 days of meeting on Draft Preliminary Site Characterization Summary

28. EPA provides the HHRA, ERA and memorandum on its risk management decision

Within 60 days of receipt of Final Preliminary Site Characterization Summary

29. Submit Draft Proposal of Preliminary Remedial Action Objectives (RAOs)

Within 30 days of receipt of EPA’s HHRA and ERA memoranda on its risk management decisions

30. Submit Draft Candidate Technologies Report to EPA Within 60 days of approval of the Final Preliminary Site Characterization Summary

31. Meeting with EPA on RAOs and Draft Candidate Technologies Report


32. Submit Final Proposal of RAOs Within 30 days of meeting on the RAOs 33. Submit Final Candidate Technologies Report Within 30 days of meeting on Draft Candidate Technologies

Report


56

003098

ACTION TIMING 34. Submit Draft Remedial Investigation (RI) Report Within 90 days of EPA approval of Final Preliminary Site

Characterization Summary, or 30 days after receipt of Human Health and Ecological Risk Assessments, whichever is greater

35. Meeting with EPA on the Draft RI Report Within 14 days of receipt of notice of meeting from EPA 36. Submit Final RI Report Within 60 days of the meeting on the Draft RI Report 37. EPA determines need for Treatability Study or Studies Within 30 days of EPA approval of the Final Candidate

Technologies Report 38. If Treatability Studies required by EPA, Submit a Draft Treatability Study Work Plan to include SAP , QAPP, and HSP .

Within 60 days of receipt of statement of need to conduct treatability study from EPA

39. Meeting with EPA on the Draft Treatability Study Work Plan


40. Submit Final Treatability Study Work Plan Within 30 days of meeting on Draft Treatability Work Plan 41. Initiate Treatability Studies Within 30 days of receipt of approval of Final Treatability

Study Work Plan 42. Submit Draft Treatability Study Report Within 45 days of receipt of final results of treatability studies 43. Meeting with EPA on the Draft Treatability Study Report


44. Submit Final Treatability Study Report to EPA Within 30 days of meeting on Draft Treatability Study Report 45. Submit Draft Development and Screening of Remedial Alternatives Report to EPA

Within 60 days of receipt of approval of Candidate Technology by EPA, or within 45 days of approval of the Final Treatability Study Report, if required

46. Meeting with EPA on the Draft Development and Screening of Remedial Alternatives Report


47. Submit Final Development and Screening of Remedial Alternatives Report to EPA

Within 30 days of the meeting on the Draft Development and Screening of Remedial Alternatives Report

48. Submit Draft Detailed and Comparative Analysis of Alternatives to EPA

Within 60 days of receipt of approval of Development and Screening of Remedial Alternatives Report by EPA

49. Meeting with EPA on the Draft Detailed and Comparative Analysis of Alternatives


50. Submit Final Detailed and Comparative Analysis of Alternatives to EPA

Within 30 days of meeting on the Draft Detailed and Comparative Analysis of Alternatives

51. Submit Draft Feasibility Study Report Within 60 days of receipt of approval of Final Detailed and Comparative Analysis of Alternatives by EPA

52. Meeting with EPA on Draft Feasibility Report Within 14 days of receipt of notice of meeting from EPA 53. Submit Final Feasibility Study Report Within 45 days of meeting on Draft Feasibility Report 54. Submit Monthly Progress Reports Within 20 days of the last day of each month

55. Submit Laboratory Protocols Within 10 days prior to beginning any analyses


57

003099

7.0 Project Schedule Figures 7.1a-c present the project schedule based on the information presented in Table 6 and assumptions concerning duration of field investigations and agency review times. The OU4 RI/FS is expected to last into the 3rd Quarter of 2006, assuming that a treatability study is not required. This schedule outlines the major activities and project milestones. The schedule will be adjusted based upon the actual time required for field investigations or Agency review and approval.


58

003100

Figure 7.1a Work Plan Tasks and Schedule


59

003101

Figure 7.1b RI Tasks and Schedule


60

003102

Figure 7.1c FS Tasks and Schedule


61

003103

8.0 References AATA 2004a. Scoping Phase Work Plan for Tar Creek OU4 RI/FS Program.

Prepared for Tar Creek Respondents and U.S.EPA Region VI, Dallas TX.

AATA 2004b. Data Gap Analysis for Tar Creek OU4 RI/FS Program.

Prepared for Tar Creek Respondents and U.S. EPA Region VI, Dallas, TX.

Aggus, L. R.,Vogele, L. E.,Rainwater, W.C., and Morais, D.I. 1982. Effects of

Acid Mine Drainages From Tar Creek on Fishes and Benthic Macroinvertebrates in Grand Lake, Oklahoma.

ASTM. 1998. Standard Guide for Soil Sampling from the Vadose Zone

(Designation: D- 4700), pp. 16. ASTM. 2003a. Standard Practice for Sampling Aggregates (Designation D-

75), pp. 5. ASTM. 2003b. Standard Practice for Reducing Samples of Aggregate to

Testing Size (Designation C-702), pp. 4. Black and Veatch Special Projects Corp. 1998. Final Jasper County

Superfund Site Baseline Ecological Risk Assessment (ERA), Jasper County, Missouri. Prepared for U.S. EPA Region VII, Kansas City KS.

Brown & Root. 1995b. Work Plan, Mining Waste, Remedial Investigation /

Feasibility Study, Tar Creek Superfund Site, Ottawa County, Oklahoma. Prepared for the U.S. Army Corps of Engineers, Tulsa District and U.S. Environmental Protection Agency.

Brown & Root. 1995a. Sampling and Analysis Plan, Mine Waste, Remedial

Investigation / Feasibility Study, Tar Creek Superfund Site, Ottawa County, Oklahoma. Prepared for the U.S. Army Corps of Engineers, Tulsa District and U.S. Environmental Protection Agency.

Brown and Root. 1997. Residential Remedial Investigation Report,

Residential Remedial Investigation/Feasibility Study, Tar Creek Superfund Site – Volumes I and II.

Brichta, L.C. 1960. Catalog of recorded exploration drilling and mine

workings, Tri-State zinc-lead district -- Missouri, Kansas, and Oklahoma: U.S. Bureau of Mines Information Circular 7993, 14 p.


62

003104

Dames & Moore. 1993. Final Remedial Investigation for Cherokee County,

Kansas CERCLA Site, Baxter Springs/Treece Subsites. Volumes I and II.

Dames and Moore 1994. Final Site Characterization Memo – Neck/Alba,

Snap, Oronogo/Duenweg, Joplin, Thoms, Carl Junction, and Waco Designated Areas, Jasper County Site, Missouri.

Dames & Moore. 1995. Final Remedial Investigation Neck/Alba, Snap,

Oronogo/Duenweg, Joplin, Thoms, Carl Junction, and Waco Designated Areas, Jasper County Site, Jasper County, Missouri. Volumes I and II.

EPA. 1988. Guidance for Conducting Remedial Investigations and Feasibility

Studies Under CERCLA. Office of Emergency and Remedial Response, U.S. Environmental Protection Agency, Washington, D.C. EPA/540/G-89/004.

EPA. 1991. Risk Assessment Guidance for Superfund: Volume 1 – Human

Health Manual, Supplemental Guidance, “Standard Default Exposure Factors”. Interim Final, OSWER Directive 9285.6-03,Washington, D.C.

EPA. 1992. Statistical Analysis of Ground-water Monitoring Data at RCRA

Facilities. Addendum to Interim Final Guidance. Office of Solid Waste, Permits and State Programs Division. U.S. Environmental Protection Agency, Washington, D.C.

EPA. 1994. EPA Requirements for Quality Assurance Project Plans. Interim

Draft. EPA QA/R-5. EPA. 1994. Five Year Review Tar Creek Superfund Site, Ottawa County,

Oklahoma. EPA. 1995. Draft Supplement, Region VI Risk Assessment Guidance. EPA. 1996a. Low-Flow (Minimal Drawdown) Ground-Water Sampling

Procedures. EPA/540/S-95/504, April 1996. EPA. 1996b. Superfund Soil Screening Guidance: User’s Guide. EPA

Publication 9355.4-23, July 1996. EPA. 2000. Standard Operating Procedures for Soil Sampling (SOP 2012).

US EPA Environmental Response Team, February 2000, pp. 13.


63

003105

EPA. 2003. Superfund Lead Contaminated Residential Sites Handbook. EPA Publication 9285.7-50, pp. 74.

Fowler, G.M. 1942. Ore deposits in the Tri-State zinc and lead district, in

Newhouse, W.H., editor, Ore deposits as related to structural features: Princeton University Press, p. 206–211.

Fowler, G.M., and J.P. Lyden. 1932. The ore deposits of the Tri-State district

(Missouri-Kansas-Oklahoma): American Institute of Mining and Metallurgical Engineers Transactions, v. 102, p. 206-251.

Gilbert, R.O. 1987. Statistical Methods for Environmental Pollution Monitoring. Van Nostrand-Reinhold, New York, pp. 164-167.

Harvey, E.J. & L.F. Emmett. 1980. Hydrology and Model Study of the

Proposed Prosperity Reservoir, Center Creek Basin, Southwestern Missouri, pp. 50.

Kabata-Pendias, A. 2001. Trace Elements in Soils and Plants, 3nd Ed. CRC

Press, Boca Raton, FL. Luza, K.V. 1986. Stability problems associated with abandoned underground

mines in the Picher Field, northeastern Oklahoma. Oklahoma Geological Survey Circular 88, 114 p.

MacFarlane, P.A., and L.R. Hathaway. 1987. The Hydrogeology and

Chemical Quality of Ground Waters from the Lower Paleozoic Aquifers in the Tri-State Region of Kansas, Missouri and Oklahoma. Kansas Geol. Survey, Groundwater Series 9. Univ. of KS.

Marcher, M.V., Kenny, J.F., and others. 1984. Hydrology of Area 40,

Western Region, Interior Coal Province, Kansas, Oklahoma and Missouri: U.S. Geological Survey Water-Resources Investigations Open-File Report 83-266, 97 p.

ODEQ. 2000. Summary Report of Washed and Unwashed Mine Tailings

(Chat) from the Tar Creek Superfund Site Area. Ottawa County, Oklahoma. Prepared by the Oklahoma Department of Environmental Quality.

Oklahoma Water Resources Board. 1983. Tar Creek Field Investigation - Task

1.4: Groundwater Investigation, in the Picher Field, Ottawa County, Oklahoma. EPA Grant No. CX810192-O1-O.

OWRB 1991. Tar Creek After-Action Monitoring Report. Water Quality

Division, 39p.


64

003106

Playton, S.J., R.E. Davis and R.G. McClaflin. 1980. Chemical Quality of Water in Abandoned Zinc Mines in Northeastern Oklahoma and Southeastern Kansas. Prepared by the USGS in cooperation with the Oklahoma Geological Survey. Circular 82.

Rantz et al. 1982. Measurement and Computation of Streamflow. United

States Geological Survey Water-Supply Paper 2175, 631 pp. Reed, E.W., S.L. Schoff, and C.C. Branson. 1955. Ground-water Resources of

Ottawa County, Oklahoma: Oklahoma Geological Survey, Bulletin 72, 203 pp.

Ruhl, O., S.A. Allen, and S.P. Holt. 1949. Zinc-Lead Ore Reserves of the Tri-

State District, Missouri-Kansas-Oklahoma. Bureau of Mines, RI # 4490.

Sileo, Louis, W. Nelson-Beyer, and Rafael Mateo. 2004. Pancreatitus in wild

zinc-poisoned waterfowl. Avian Pathology 32(6), 655-660. Stroup, R.K., and R.B. Stroud. 1967. Zinc-lead mining and processing

activities and relationship to land-use patterns, Ottawa County, Oklahoma: U.S. Bureau of Mines unpublished report, 22 p.

TCSTF. 2000. Governor Keating’s Tar Creek Superfund Task Force, Water

Quality Subcommittee Task 1 Report, Surface Water and Groundwater Monitoring.

TCSTF. 2000. Governor Keating’s Tar Creek Superfund Task Force, Native

American Issues Subcommittee Final Report, 12 p. By E. Hatley, (Coordinator).

US Census Bureau. 2004. Web Site:

http://quickfacts.census.gov/gfd/states/40/40115.htm, accessed January 22, 2004.

USGS. 2004. National Water Information Service, Surface Water Data for

Oklahoma, USGS Gage Site No. 07185095, Tar Creek at 22nd St. Bridge, Miami, OK. Period of Record 1984-1993


65

003107

http://quickfacts.census.gov/gfd/states/40/40115.htm




Appendix 1

Abbreviations and Acronyms AATA AATA International, Inc. ABS Absorption ANOVA Analysis of Variance AOC Administrative Order on Consent ARARS Applicable or relevant and appropriate requirements ATSDR Agency for Toxic Substances and Disease Registry B&RE Brown & Root Environmental BIA Bureau of Indian Affairs BRA Baseline risk assessment CERCLA Comprehensive Environmental Response Compensation and

Liability Act CFR Code of Federal Regulations CLP Contract laboratory program COPCs Chemicals of Principal Concern COE Corps of Engineers CSF Cancer slope factor DBH Diameter Breast Height DGA Data Gap Analysis District Tri-State Mining District DQOs Data quality objectives DSP Data Security Plan DXF Data exchange format DXS Data exchange standard EPA Environmental Protection Agency ERA Ecological risk assessment ERMA Environmental Resource Management Application FS Feasibility Study FSP Field Sampling Plan GIS Geographic information system GPS Global positioning system HSP Health and safety plan HHRA Human health risk assessment IAG Interagency agreement IMS Information management system LOAEL Lowest-observed-adverse-effect-level MCL Maximum contaminant levels MCLG Maximum contaminant level Goals MDL Method Detection Limit MPH Miles per hour MSL Mean sea level NCP National Contingency Plan NIOSH National Institute of Occupational Safety and Health


003108

NAAQS National Ambient Air Quality Standards NAEL No-adverse-effect-level NOAEL No-observed-adverse-effect-level NPDES National Pollution Discharge Elimination System NPL National Priorities List OK Oklahoma OSDH Oklahoma State Department of Health OSHA Occupational Safety and Health Administration OWRB Oklahoma Water Resources Board PAHs Polycyclic aromatic hydrocarbons PM-10 Particulate matter less than 10 micron in size PRPs Potentially Responsible Parties QA/QC Quality Assurance/Quality Control QAPP Quality Assurance Project Plan RAA Remedial action alternatives. RAOs Remedial action objectives RCRA Resource Conservation and Recovery Act RfD Reference dose RI Remedial Investigation ROD Record of Decision SAP Sampling and Analysis SDS Spatial data standard SOW Statement of Work Site Tar Creek Superfund Site SMDP Scientific/management decision point TAL Target analyte list TAT Technical assistance team TBC To be considered TCL Target Compound List TSCA Toxic Substances Control Act TSP Total suspended particulates TSS Total Suspended Solids TZ Transition Zone UCL Upper confidence limit USGS United States Geological Survey WP Work Plan XRF X-ray fluorescence


003109

Appendix 2

Work Plan Revision Form Tar Creek OU4 RI/FS, Tar Creek Site, Ottawa County, Oklahoma

1. Date:

2. Prepared By:

3. Requested Revisions (use additional sheets if needed):

4. Justification (use additional sheets if needed): Authorization: 5. Remediation Project Manager: Date: 6. Technical Project Manager: Date: 7. __________________________\Approved _____ Rejected

____ Approved subject to the following conditions: Accepted: Project Manager: Date:


003110