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This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsi- bility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Refer- ence herein to any specifc commercial product, process, or seMce by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recom- mendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.

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GEOLOGIC REPORT

NIAGARA . FALLS c STORAGE SITE -

JUNE 1984

Prepared for

UNITED STATES DEPARTMENT OF ENERGY

OAK R I D G E OPERATIONS OFFICE Under Contract DE-AC05-810R

DOE/OR/20722--

DE84 013459

__^ _ *^^9 BECHTELl. National, Inc. Advanced Technology Division Oak, Sidge, Tennessee

.>

• , I

DISCLAIMER

This report was prepared as an account of work sponsored by an

agency of the United States Government. Neither the United States

Government nor any agency Thereof, nor any of their employees,

makes any warranty, express or implied, or assumes any legal

liability or responsibility for the accuracy, completeness, or

usefulness of any information, apparatus, product, or process

disclosed, or represents that its use would not infringe privately

owned rights. Reference herein to any specific commercial product,

process, or service by trade name, trademark, manufacturer, or

otherwise does not necessarily constitute or imply its endorsement,

recommendation, or favoring by the United States Government or any

agency thereof. The views and opinions of authors expressed herein

do not necessarily state or reflect those of the United States

Government or any agency thereof.

DISCLAIMER

Portions of this document may be illegible in

electronic image products. Images are produced

from the best available original document.

FOREWORD

This report is one of a series of engineering and environmental reports planned for the U. S. Department of Energy's properties at Niagara Falls, New York. The report describes the essential geologic features of the Niagara Falls Storage Site. It is not intended to be a definitive statement of the engineering methods and designs required to obtain desired performance features for any permanent waste disposal at the site. Such requirements, if developed, will be reported separately.

iii

TABLE OF CONTENTS

i

1.

Introduction

1.1 Purpose 1.2 Previous and Related NFSS Reports

Geology

2.1 Regional Geology 2.2 Site Geology 2.2.1 Site Stratigraphy 2.2.2 Ground Water

Program Description

3.1 Phase 1 Program 3.2 Phase 2 Program 3.2.1 South Dike Area 3.2.2 R-10 Dike Area 3.2.3 Northern Disposal Area 3.2.4 K-65 Tower Area

Phase 1 Investigation

4.

Exploration Methods 4.1.1 Geologic Mapping 4.1.2 Geophysical Surveys 4.1.3 Exploratory Drilling Findings of^ the Phase^1 Investigation 4.2.1 East Dike, R-10 Dike Area 4.2.2 North Dike, R-10 Dike Area 4.2.3 West Dike, R-10^ Dike Area 4.2.4 Analysis of Contaminant Migration

Page

1

2 2

11

V

5.0 Phase 2 Investigation

5.1 Exploration Methods 5.1.1 Geophysical Measurements 5.1.2 Test Pit Excavation 5.1.3 Exploratory Drilling 5.1.4 Vibrating Wire Piezometers 5.1.5 Observation Wells 5.2 Findings of Phase 2 Investigations 5.2.1 Brown Clay Unit 5.2.2 Gray Clay Unit 5.2.3 Sand and Gravel Unit 5.2.4 Bedrock Hydrogeology 5.2.5 Analysis of Contaminant Migration

6.0 Findings

7.0 Conclusions

8.0 Continuing Geotechnical Activities

REFERENCES

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Page 23

n

LIST OF TABLES

Id Table Title

1 Phase 1 Exploration Summary, R-10 Dike Investigation 2 Phase 2 Exploration Summary 3 Summary of Gray Clay Depths -- Phase 1, R-10 Dike Investigation 4 As-Built Data -- Observation Wells 5 Field Permeability Test Results 6 Summary of Gray Clay Depths -- Phase 2 7 Water Levels/Vibrating Wire Piezometers

v i i

Page 40

41 4 2

4 3 44 45 4 6

LIST OF FIGURES

(&Figure

10 11 12

13

14

Title Site Location Map Site Plan Showing the Four Areas of Investigation Allegheny Plateau to Laurential Plateau, North-South Section Generalized Geologic Column Isopach of Gray Clay Boring Location Plan -- R-10 Area (Phase 1) Boring Location Plan (Phase 2 ) Surficial Geologic Map, R-10 Dike Area Explanation to Geologic Map Profiles in R-10 Dike Foundation Area

Location of Geologic Sections (Phase 2)

Profile East of 411 Building -- Geologic

Section A-A' Profile South of 411 Building -- Geologic Section B-B' Profile West of 411 Building -- Geologic Section C-C' Northern Disposal Area --^ Geologic Section^ D-D' Northern Disposal Area -- Geologic Section E-E' Profiles Though K-65 Tower Area Bedrock Water Level Contour Map -- Queenston Formation

Page 4 7 48 49

5 0 5 1 5 3 5 5 57 5 9 61 63 64

65

66

69 71

ix

n

Appendix

A B C D E F G H I J K L M

LIST OF APPENDICES

Title Test Pit Logs (Phase 1) Harding Lawson Geophysical Survey (Phase 1) Boring Logs (Phase 1) Contaminant Migration Analysis Weston Geophysical Report (Phase 2) Test Pit Logs (Phase 2) Boring Logs (Phase 2) Acres American Boring Logs Piezometer Completion Reports Water Analysis -- Borings A-23, A-23A, A-35, A- Abandonment of Well W- Observation Well Completion Reports (Phase 2) Observation Well Hydrographs (Phase 2)

Page A- B- c- D- E- F- G- H - 1 1- J- K- 1- M-

xi

1.0 INTRODUCTION

The Niagara Falls Storage Site (NFSS) is a U.S. Department of Energy (DOE) surplus facility located in Lewiston Township, Niagara County, New York. of this report. The 77-ha (191-acre) site is a small portion of the original Lake Ontario Ordnance Works (LOOW) and was formerly used for uranium ore processing and radioactive waste storage and

transshipment. It is currently being managed for DOE by the

Advanced Technology Division of Bechtel National, Inc., (BNI), Oak Ridge, Tennessee, as part of the DOE Surplus Facilities Management Program (SFMP) established to manage and plan the ultimate disposition of surplus DOE-owned facilities. Portions of the former LOOW site and other vicinity properties are within the jurisdiction of the SFMP'S companion DOE program, the Formerly Utilized Sites Remedial Action Program (FUSRAP), which evaluates former Manhattan Engineer District/Atomic Energy Commission (MED/AEC) sites and conducts remedial action activities where appropriate.

The location of the site is shown on Figure 1 at the end

An inventory of radioactive residues and wastes is stored at the NFSS. Some areas of the site have also become contaminated from previous burial and spills of contaminated materials, and from radionuclide migration along drainage pathways. A plan of the site is shown on Figure 2.

The R-10 and South Dike Areas had been identified as planned

locations for interim storage of contaminated materials from on-site

and vicinity property cleanup activities; the Northern Disposal Area for the storage of a portion of the vicinity property cleanup, if required; and the K-65 Tower Area for temporary storage of residues from inside the tower. Planned storage facilities include shallow burial within a diked containment area.

This report presents the results of a geological investigation by

BNI which consisted of two phases. Phase 1 occurred during July

1982 and included geologic mapping, geophysical surveys, and a limited drilling program in the vicinity of the R-10 Dike (Figure 2). Phase 2, initiated in December 1982, included excavation of 1

test pits, geophysical surveys, drilling, observation well installation, and field permeability testing in the South Dike Area, the Northern Disposal Area, and the K-65 Tower Area.

1.1 PURPOSE

The purposes of the Phase 1 investigation were to document the dike foundation materials and to report the existence of zones of potentially high permeability. the dike foundation area, the scope of the investigation was expanded to determine the extent and depth of the sand zones within the surficial brown clay unit. During the Phase 1 investigation, construction of a confining dike around the R-10 Dike Area was in progress.

When zones of sand were found within

The purposes of the Phase 2 investigation were to determine whether the gray clay unit is continuous beneath the surficial brown clay unit at the NFSS and to extend the knowledge of site stratigraphy by expanding on data from previous investigations so that-the

suitability of the site for long-term storage of low-level

radioactive wastes could be assessed. The Phase 2 investigation characterized the subsurface materials in areas where little or no data were available from earlier investigations; provided documentation of the depth, character, and thickness of the gray clay unit; and reported on the existence of sand and gravel deposits within the brown clay unit. Documentation of observation wells installed in known sand pockets in the R-10 Dike Area was also provided.

1.2 PREVIOUS AND RELATED NFSS REPORTS

Prior to the BNI Phase 1 and 2 geological investigations, Acres American, Inc. of Buffalo, New York prepared a report (Ref. 1) that presents an evaluation of the geology and hydrology of the NFSS. In the Acres American report the glacial sediments are divided into five units. In order of increasing depth, these units are: surficial soils and fill, brown clay, gray clay, sand and gravel, and red silt. 2

n

In addition to the Phase 1 and 2 geological investigations a contaminant migration study was performed by BNI in support of remedial action at the site. Study details and results are presented in the Waste Containment Design Report for the Niagara Falls Storage Site (Ref. 2 ) , which also contains the details and

results of a site seismicity study. The work completed and reported in the Design Report complements the work completed during the Phase 1 and 2 investigations.

The Environmental Impact Statement (Ref. 3 ) prepared by Argonne National Laboratory provides an independent analysis and comparison

of conceptual containment systems at the NFSS with alternatives at

another humid eastern site and an arid western site.

3

2.0 GEOLOGY

2. 1 REGIONAL GEOLOGY

Grs

The NFSS lies within the Central Lowland Physiographic Province, which is part of the Erie-Ontario Lowland and is characterized by topography developed on essentially undeformed Paleozoic sedimentary

rocks from the Ordovician and Silurian Periods which were deposited

between 400 and 450 million years ago. The rocks have a regional dip of less than one degree and occupy a broad basin sloping gently southward from the neighboring crystalline terrains of the Canadian Shield and the Adirondack Dome (Ref. 4 ). A metamorphic basement of

gneiss has been found in wells at depths varying from approximately

610 to 914 m (2,000 to 3,000 ft) (Ref. 5 ). The area was

significantly modified by glaciers. Variable erosional resistance

of the sedimentary rocks, combined with their gentle dip, resulted

in a series of east-west trending escarpments and low plains

(Ref. 6).^ Figure^^3 presents a generalized geologic section through the area illustrating these features.

The sedimentary rocks of the region consist predominantly of carbonates and fine clastic rocks. The uppermost bedrock in the vicinity of the NFSS is the Ordovician Queenston Formation, a silty shale or mudstone. To the south, the Niagara Escarpment is formed from rocks of the Medina Group (sandstone, siltstone, shale), the Clinton Group (limestone, dolomite, shale), and the Lockport Group (dolomite, limestone), which is the cap rock of the Escarpment.

Approximately 20 miles south of the Escarpment, near Buffalo, the

Lockport Group is overlain by the Salina Group (shale, gypsum).

Surficial deposits cover most of the Niagara County area and are described and mapped in detail by-Kindle and Taylor (Ref. 6). The deposits of the Quaternary Period belong almost entirely to the late Pleistocene (approximately 12,000 years before present) and include glacial drift and associated lacustrine deposits. With the

exception of minor exposures of bedrock, these deposits cover almost

the entire area.

5

The glacial deposits consist of till, principally from the most

recent glaciation (late Wisconsin), and stratified drift in the form

of kames, eskers, and sheets of outwash sand and gravel. The lacustrine materials were deposited on the bottoms and along the shores of glacial and post-glacial lakes.

2.2 SITE GEOLOGY

The stratigraphy and ground-water regime of the site have been reported previously by Acres American, Inc. (Ref. 1). That report forms the basis for the following sections on site stratigraphy and ground water.

2.2.1 Site Stratigraphy

The site stratigraphy includes 12 to 15 m ( 4 0 to 5 0 ft) of unconsolidated deposits overlying a thick sequence of sedimentary rocks. These surficial deposits are glacially derived sediments, which include glaciofluvial sands and gravel, dense tills, and glacial lacustrine clays. Beneath these deposits are shales, siltstones, and mudstones of the Queenston Formation.

S i x major units are identified within the interval from zero to 27 m ( 9 0 ft) below ground surface. In order of increasing depth, these units are: surficial soils and fill, brown clay, gray clay, sand

and gravel, red silt, and bedrock of the Queenston Formation. A

generalized stratigraphic column for the site is presented in Figure

4. Detailed descriptions of these units from youngest to oldest are presented below.

Surficial Soils and Fill*

Soil at the site is generally a loose to medium dense, brown or yellowish silt with organic matter usually present in the upper 15 cm (6 in.) (root zone). Gravel and sand are generally

9

*Refer to the first page of Appendix G for an explanation of terms used to describe soils and rock. b

Grl (^) encountered during exploration and are dispersed randomly throughout

this unit. The thickness of the surficial soils varies between 0 and 1.5 m (5 ft), averaging 0.3 to 0.6 m (1 to 2 ft). The unit is generally dry to moist and occasionally saturated. The unit is described as fill where man-made materials (e.g., glass and bricks) and obvious signs of disturbance were encountered.

Brown Clay Unit

Brown clay, which is thought to be predominantly glacial till, underlies the surficial soils. This unit was modified during submergence beneath glacial Lake Iroquois. Some lamination of the clay and deposition of sandy or gravelly zones within the clay resulted from this modification (Ref. 6).

Brown or reddish brown clay is predominant in this unit, and sand and silt are present in the form of seams, pockets, and lenses. Sandy gravel and gravelly sand and silt lenses are common within the basal portion of the unit. Regardless of the variability of the

materials within the unit, for purposes of discussion it is referred

to as the brown clay unit.

Beneath the site the brown clay varies in thickness from 2 to 7 m (6

to 23 ft). The consistency of the clay within the unit ranges from

hard to medium soft. The clay is dry to moist and exhibits low to medium plasticity with increasing depth. Gravel is dispersed throughout the clay portion of this unit. In general, the unit varies in classification from a clayey silt to a silty clay.

The sand, gravel, and silt lenses common within the basal portion of

the brown clay average 0.3 to 1.5 m (1 to 5 ft) in thickness. The

thickness and lateral extent of these lenses vary abruptly. The

sediments in these lenses are moist to saturated and vary from loose to dense. More extensive deposits of sand and gravel, 5.3 m (17.5 ft) and 6.1 m ( 2 0 ft) thick also occur within this unit.

7

Gray Clay Unit

The gray clay is of lacustrine origin and was deposited in the deeper portions of glacial Lake Iroquois (Ref. 6). Some post-depositional erosion of the unit is evident from the channels along its upper surface which are filled with coarser grained sediments of the overlying brown clay unit.

In general, this unit is the thickest unconsolidated unit on-site, varying from less than 1.5 m (5 ft) to about 9 m (30 ft) in

thickness within the areas of investigation (Figure 5), and is

characterized by gray clay that occasionally grades vertically to a silt and clay mixture. Gravel is dispersed throughout the unit as are pockets of fine to medium grained sand. Sand and gravel become

the predominant constituents near the base of the unit.

The overall consistency of this unit ranges from soft to medium soft. The clay is saturated, and sand lenses are wet to saturated. The clay portion of the unit is slightly to highly plastic.

There are some lateral facies changes within the upper 0.9 to 1.5 m ( 3 to 5 ft) of the gray clay unit which typically consist of an increase in silt and sand content.

Sand and Gravel Unit

This unit consists of a mixture of sand and gravel with silt. On-site, the unit varies from a clean silt to a sandy gravel, is normally wet to saturated, and exhibits a loose to medium relative

density. In general, the thickest portions of the unit are present

where depressions in the bedrock surface occur (Ref. 1). The sand and gravel are thought to be of glaciofluvial origin.

The sand and gravel unit is considered a major water-bearing zone

on-site and is discussed in Subsection 2.2.2 of this report.

8

bj Red Silt Unit

Poorly sorted and unstratified units such as the red silt unit are classified as a till. The presence of angular fragments of bedrock in the sandy silt matrix suggests that this till was locally derived and emplaced as a basal till (Ref. 1).

The red silt unit is distinguished from the other units because of

its color and high density. Typically, it is composed of clayey,

gravelly silt with lesser amounts of sand. Gravel is dispersed through out the unit and consists of both rounded gravel and angular fragments of bedrock. This unit is dry to moist, overconsolidated, and ranges from medium to very dense. The red silt varies in thickness and in some locations is absent.

Queenston Formation

The bedrock unit at the site consist-s of brownish-red shales, siltstone and mudstone of the Queenston Formation. Within this formation, occasional lenses of green siltstone and shale occur in the rock mass. The bedrock is slightly to moderately weathered in the upper few feet.

2.2.2 Ground Water

Within 30 m (100 ft) of the ground surface, two general types of water-bearing materials occur. These are the bedrock of the Queenston Formation and select permeable zones within the overlying unconsolidated deposits. The water-bearing characteristics of the unconsolidated deposits (overburden)-are presented in the following paragraphs.

The two significant water-bearing zones within the overburden are the intermittent sand, gravel and silt lenses found in the brown

clay unit between elevations 91.5 and 96.6 m ( 3 0 0 and 317 ft) m.s.1.

and the sand and gravel unit immediately below the gray clay unit,

9

typically between elevations 82.3 and 91.4 m (270 and 300 ft) m.s.1.

(Ref. 1). Both zones are described in the generalized geologic column presented in Figure 4.

Although the lenses of gravel, sand, and silt in the brown clay unit are discontinuous, the sand zones in that unit are referred to as the upper aquifer. The sand and gravel unit between the red silt unit and the gray clay unit is referred to as the lower aquifer.

Upper Aquifer

The sand, gravel, and silt lenses encountered within the brown clay unit are referred to in the Acres American report (Ref. 1) as the upper soil aquifer. These lenses vary abruptly in thickness and extent, and are not considered continuous across the site, T h i s

lack of continuity is discussed in Section 5.0. These lenses range

from dry to saturated. The rate of ground-water flow in the lenses also varies significantly from one location to another.

Lower Aquifer

The lower aquifer at the NFSS is the 0.9 to 2 m-thick (3 to 7 ft-thick) sand and gravel unit found between elevation 82.3 and 91.4 m (270 and 300 ft) m.s.1. This aquifer is confined between the underlying red silt unit and the overlying gray clay unit. Gravel quantities vary from 0 to about 40 percent of the aquifer unit. At different locations on-site the unit may grade to sand and gravel

with little or no clay or silt; a silt with little or no sand or

gravel: or a mixture of sand, gravel, silt, and clay (Ref. 1). At a few locations the unit is absent.

Measurements of water levels in wells constructed during the Acres American, Inc. exploration program indicate that the aquifer is confined. Water level measurements in July 1981 show the potentiometric surface between 95.4 and 96.3 m (313 and 316 ft) m.s.l., which is 7.6 to 9.1 m (25 to 30 ft) above the top of the aquifer (Ref. 1).

10

Queenston Formation

The top of the Queenston Formation is weathered and fractured. Ground-water movement in this formation is primarily in this weathered zone. Water levels recorded by Bechtel in April 1983 indicate that the ground water is confined and has a potentiometric

surface which is an average of 11.3 m ( 3 7 ft) above the top of the

aquifer. The confining layer for the Queenston Formation is the overlying red silt unit. Where this unit is absent, the Queenston is hydraulically connected with the lower aquifer (Ref. 1).