REGION VIII
SUPPLEMENTARY GUIDANCE FOR PERFORMING
PRELIMINARY ASSESSMENTS UNDER CERCLA
August 20, 1993

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August 1993
EPA REGION VIII
Preliminary Assessment Guidance
U. S. EPA Headquarters released National Preliminary Assessment (PA)
Guidance in September 1991. Region VIII issued Regional PA Guidance shortly
thereafter, to focus the Guidance on Regional data collection needs. After one
year of implementation, the Region finds that the Regional PA Guidance should be
revisited. This guidance replaces the previous regional Guidance of January 1992
and continues to act as supplement to the National PA Guidance. The Region
places a priority on clearly differentiating between fact and interpretation in the PA
deliverables. This remains the primary reason for the regional supplemental
guidance. This guidance also clearly defines the deliverable which is to be
submitted to EPA in Region VIII.
Knowledge of the Hazard Ranking System (HRS) is critical to the
performance of PAs and Sis under Superfund. Data elements should be collected
and reported with HRS criteria in mind. The Region promotes the use of the
PREscore computer program as a learning tool and as a tool to determine when
enough relevant data has been collected and now requires PREscore as part of the
PA deliverable.
Deliverables
Basic data should be collected with the assistance of the PA Worksheets,
Attachment V. This is intended to be submitted to the Region as part of the PA,
and should be typed. The PA narrative is a presentation of the facts, with a
summary which highlights the most relevant data elements with respect to the
HRS. The text and worksheets are not appreciably different from the format we
have used for the last several years in this region, however the worksheet has
been revised. The PA Worksheets should prompt the writer to include pertinent
data elements in the text. No interpretation should appear in any part of the PA
deliverable without factual support in the PA narrative or worksheets. Because the
PA Form requires interpretation (of primary and secondary targets) on pages 3 and
4, only pages 1 and 2 will be filled out in the current deliverable. Data elements
requested on pages 3 and 4 of the PA form are incorporated, without interpretive
interference, in the PA Worksheet.
The Region finds that PA-score is not a worthwhile use of contractor or EPA
resources in this part of the country. There was not a close correlation between
PA-scores and PREscores run using the same basic data. Both false-positive and
false- negative decisions to perform Sis were possible (12% and 18% of cases
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PA Guidance
EPA Region VIII
August 1993
respectively) using PA-score. PA-score is no longer part of the required deliverable.
It has been replace by PREscore. It is our intention to continue to make accurate
data collection the focus of the PA, rather than interpretation (via scoring models).
Federal Facilities
Federal Facilities are not required or expected to submit scores of any kind
to this Region as part of a PA or equivalent under CERCLA 120 (d). The basic
facts as outlined on the PA Worksheets are our highest need. However, if any PA
scores or scoresheets are created, the Region requests they be sent for our
information. We will retain them as part of the file, and consider them in the
decision process. As stated above, no interpretation should appear without factual
support in the PA text or worksheets.
Freedom of Information Act (FOIA) Issues
All scores are interpretive and some PA-scores and PREscores will exist in
our files which have not been checked for accuracy and documentation. They will
sometimes contain hypothetical samples or conditions which help us determine
whether it is reasonable to believe a particular site could have the potential to be a
candidate for the NPL. The Agency does not stand behind these scores. Official
scores are only those printed in the Federal Register for proposal or finaiization on
the NPL.
As a matter of policy, the EPA does not release predecisional material. The
Region applies this to scores and interpretive documents, except the PA form, by
not releasing them until a final determination is complete. Once a No Further
Remedial Action Planned (NFA or NFRAP) decision has been made, the materials
used in making that decision, including the score if one exists, will be released
upon request. Official scores are always released upon request after NPL proposal
or final listing.
PA Short Format
There are a number of sites which may require Preliminary Assessments
under CERCLA pursuant to the National Contingency Plan but which are quickly
eliminated as candidates for the National Priorities List (NPL) under Superfund.
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PA Guidance
EPA Region VIII
August 1993
These sites may qualify for a less cumbersome and less time consuming PA than
other sites. These can include sites for which a complete removal has been
performed by EPAs Emergency Response Branch, or where the waste is no longer
present; sites where the waste is fully contained and a release is found not to have
occurred, RCRA subtitle C permitted facilities where an effective corrective action
plan is in place, or sites which are under a Federal Nuclear Regulatory Commission
(NRC) permit. PA Deliverables required are itemized on the Table of Preliminary
Assessment Activities and Deliverables. The PA narrative may be as little as
several paragraphs. It may include as little as sections 1.0, 3.0, 5.0, the PA Form
(p. 1 and 2), and Attachment III. Consult the EPA Site Assessment Manager
(SAM) to determine whether an individual site is eligible for this reduced reporting
format.
Conclusions
Recommendations for future work, site priority, HRS listing potential or NFA
status of a site are not appropriate in the body of a PA report. They are welcome
in the cover letter which accompanies the report. Site scores, if they are
generated, should not appear in any part of the report. References to site scores
should not appear in the text.
Conclusions should generally summarize the most critical data elements
gathered in the PA such as identified targets, potential pathways of exposure, data
needs, etc.
Attachments:
I	Activities and Deliverables Table
II	Sample PA Narrative Table of Contents
III	CERCLA Eligibility Worksheet
IV	PA Form
V	PA Worksheets
This acts as a Regional Addendum to the National PA Guidance.
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PA Guidance
EPA Region VIII
August 1993
ATTACHMENT I
PRELIMINARY ASSESSMENT
ACTIVITIES and DELIVERABLES
Activity/Deliverable
-PA Worksheet
-CERCLA Eligibility Worksheet
-Site Recon (windshield survey)
Photo Log
Separate Site Visit Report
Initial Health and Safety Plan
-Aerial Photography **
-PA Report (narrative)
(condensed narrative)
-EPA PA report Form 2050-0095
PA Form—1st 2 pages only
-PREscore
Deliverable Type
PA Short Form Standard PA
optional by case x
x
x
x
x
x
x
* with EPA approval, not required.
** where available
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PA Guidance
EPA Region VIII
August 1993
ATTACHMENT II
PRELIMINARY ASSESSMENT NARRATIVE REPORT
TABLE OF CONTENTS (AS OF 1/24/92)
1.0 INTRODUCTION
Include site name, location, CERCLIS ID; contractor or State agency
performing PA, contract and work assignment numbers or cooperative agreement-
mention Cooperative Agreement if applicable. State that the work is being
performed under Superfund.
2.0 OBJECTIVES—State PA objectives. Specify that this is under Superfund.
3.0 SITE DESCRIPTION
3.1	Site location, description-include township and range, county, street
address, and aliases as applicable.
3.2	Site history, including history of hazardous substance related activities
and regulation.
3.3	Site characteristics: Physical geography, geology, hydrogeology,
hydrology, meteorology (air studies only).
4.0 PRELIMINARY PATHWAY ANALYSIS-presented by pathway
4.1	Waste Characterization-contaminant quantity, concentrations, source
types, waste streams, containment.
4.2	Air Pathway-meteorology, air targets, evidence of release (analytic,
direct observation, or strong possibility of release)
4.3	Ground Water Pathway-hydrogeologic setting, GW targets, evidence
or likelihood of release
4.4	Surface Water Pathway-hydrologic setting, SW targets, evidence or
likelihood of release
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EPA Region VIII
August 1993
4.5 Soil Exposure Pathway-soil conditions, SE targets, likelihood of
resident population
5.0 SUMMARY and CONCLUSIONS-summarize the most important findings of
the PA. Clearly identify principle pathways and targets of concern.
6.0 REFERENCES
FIGURES
1.	General Location Map
2.	Detailed site map
3.	Additional maps to support PA (i.e., well locations)
TABLES
as needed to support the PA
APPENDICES
A.	EPA Preliminary Assessment Form
B.	Preliminary Assessment Worksheets
C.	CERCLA Eligibility Worksheet
D.	Photo Log
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PA Guidance
EPA Region VIII
August 1993
ATTACHMENT III
CERCLA ELIGIBILITY WORKSHEET

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PA Guidance
EPA Region VIII
August 1993
CERCLA Eligibility Worksheet
Site Name
City	 State
EPA ID Number
Note: The site is automatically CERCLA eligible if it is a Federally owned or
operated RCRA site.
I.	CERCLA Eligibility
Did the facility cease operations prior to November 19,1980?
If YES, then STOP. The facility is probably a CERCLA site.
If NO, continue to part II
II.	RCRA Deferral Factors
Did the facility file a RCRA Part A
application?
If YES:
1.	Does the facility currently have interim status?		
2.	Did the facility withdraw its Part A application?		
3.	Is the facility a known or possible protective filer? (filed in error) 	
4.	Does the facility have a RCRA operating or post closure permit? 	
5.	Is the facility a late (after 11/19/80) or non-filer that has been identified
by the EPA or the State? (facility did not know it needed to file under
RCRA)		
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EPA Region VIII
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Type of facility:
Generator	 Transporter	Recycler
TSD (Treatment/Storage/Disposal)	
If all answers to questions 1, 2, and 3 are NO, STOP. The facility is a CERCLA
eligible site.
If answer to #2 or #3 is YES, STOP. The facility is a CERCLA eligible site.
If answer to #2 and #3 are NO and any other answer is YES, site is RCRA,
continue to part III.
III. RCRA Sites Eligible for the NPL
Has the facility owner filed for bankruptcy under Federal or State
laws?
Has the facility lost RCRA authorization to operate or shown probable
unwillingness to carry out corrective action?		
Is the facility a TSD that converted to a generator, transporter or recycler
facility after November 19,1980?		
IV. Exempted substances:
Does the release involve hazardous substances other than petroleum?	
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PA Guidance
EPA Region VIII
August 1993
V. Other programs: The site may never reach the NPL or be a candidate for
removal. We need to be able to refer it to any other programs in EPA or state
agencies which may have jurisdiction, and thus be able to effect a cleanup.
Responses should summarize available information pertaining to the question.
Include information in existing files in these programs as part of the PA. Answer
all that apply.
Is there an owner or operator?
NPDES-CWA: Is there a discharge water containing pollutants with surface
water through a point source (pipe, ditch, channel, conduit, etc.)?
CWA (404): Have fill or dredged material been deposited in a wetland or on
the banks of a stream? Is there evidence of heavy equipment
operating in ponds, streams or wetlands?
UIC-SDWA: Are fluids being disposed of to the subsurface through a well,
cesspool, septic system, pit, etc.?
TSCA: Is it suspected that there are PCB's on the site which came from a
source with greater than 50 ppm PCB's such as oil from electrical
transformers or capacitors?
FIFRA: Is there a suspected release of pesticides from a pesticide storage
site? Are there pesticide containers on site?
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PA Guidance
EPA Region VIII
August 1993
RCRA (D): Is there an owner or operator who is obligated to manage solid
waste storage or disposal units under State solid waste or ground
water protection regulations?
UST: Is it suspected that there is a leaking underground storage tank
containing a product which is a hazardous substance or petroleum?
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PA Guidance
EPA Region VIII
August 1993
ATTACHMENT IV
PA Form

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OMB Approval Number: 2050-0095
Approved for Use Through: 1/92
5-EPA Potential Hazardous
Waste Site
Preliminary Assessment Form
Identification
Stale:
CERCUS Number
CERCL1S Discovery Date:
1. General Site Information
Name:
Street Address:
City:
State:
Zip Code:
County:
Co. Code:
Cong.
DhL

Longitude;
Approximate Area of Site:
	Acres
______ Square Ft
Status of Site:
	~ Active ~ Not Specified
G Inactive 0 NA (GW plume, etc.)
2. Owner/Operator Information
Owner
Operator
Street Address:
Street Address:
City:
City:
Stale:
Zip Code:
Telephone:
(
State:
Zip Code:
Telephone:
( )
Type of Ownership:
~	Private
~	Federal Agency
Name
~	State
~	Indian
~	County
~	Municipal
G Not Specified
Q Other	
How Initially Identified:
G Citi2co Complaint
G PA Petition
G State/Local Program
G RCRA/CERCLA Notification
G Federal Program
G Incidental
G Not Specified
Q Other
3. Site Evaluator Information
Name of Evsluator:
Agency/Organization:
Date Prepared:
Street Address:
City:
State:
Name of EJ>A or State Agency Contact:
Street Address:
City:
State:
Telephone:
( )
4. Site Disposition (for EPA use only)
Emergency Response/Removal
Assessment Recommendation:
~	Yea
~	No
Dale:
CERCLIS Recommendauon:
O Higher Priority SI
O Lower Priority SI
Q NFRAP
Q RCRA
O Other	
Dale:
Signature:
Name (typed)
Position:
D-3

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O, CPA Potential Hazardous Waste Site
Preliminary Assessment Form - Page 2 of 4
CERCLIS Number
5. General Site Characteristics
Predominant Land Uae> Within 1 Mile of Site (check til that apply):
~	Industrial	~ Agriculture ~ DOI
Q Commercial ~ Mining	~ Other Federal Facility
~	Reaidenliai ~ DOD		
~	Forest/Fields ~ DOE
~ Other
Site Setting:
~	Urban
~	Suburban
~	Rural
Yean of Operation:
Beginning Year _
Ending Year _
~ Unknown
Type of Site Operations (cheek all that apply):
~ Manufacturing (muat check subcategory)
~	Lumber and Wood Product!
~	Inorganic Chemicals
G Plastic and/or Rubber Products
Q Paints, Varnishes
G Industrial Organic Chemicals
G Agricultural Chemicals
(e.g., pesticides, fertilizers)
G Miscellaneous Chemical Products
(e.g., adhcaives, explosives, ink)
Q Primary Meuls
O Metal Coating, Plating, Engraving
G Metal Forging, Stamping
G Fabricated Structural Metal Products
G Electronic Equipment
G Other Manufacturing
G Mining
G Metals
G Coal
G Oil and Oaa
G Non-metallic Minerals
G Retail
G Recycling
G Junky Salvage Yard
O Municipal Landfill
Q Other Landfill	
G DOD
DOE
DOI
Waste Generated:
~ Onsite
G Offsite
G Onsite snd Offsite
Other Federal Facility_
RCRA
~	Treatment. Storage, or Disposal
~	Larg e Quantity Generator
G Small Quantity Generator
G Subtitle D
C Municipal
~ Industrial
O 'Convener"
0 "Protective Filer'
G "Noo- or Late Flier"
G Not Specified
O Other	
Waste Deposition Authorized By:
G Present Owner
O Former Owner
G Present Jt Former Owner
G Unauthorized
G Unknown
Waste Accessible to the Public:
G Yes
G No
Distance to Nearest Dwelling,
School, or Workplace:
	 Feet
6. Waste Characteristics information
Source Waste Quantity:
(include units)
Source Type:
(check ail that apply)
~	Landfill
~	Surface Impoundment
~	Drums
O Tanks and Moo-Drum Containers
G	Waste Pile
~	Scrap Metal or Junk Pile
O Tailings Pile
G Traah Pile (open dump)
G Land Treatment
~	Cooummated Ground Water Plume
(unidentified source)
G Contaminated Surface Water/Sediment
(unidentified source)
G Cooummated Soil
G Other
G No Sources
C « Constituent, W = Wastes (ream. V = Volume. A — Area
Tier
General Types of Waste (check all that spply)
G Metals
G Orgamcs
G Inorganics
G Solvents
G Paints/Pigments
G Pesticides/Herbicides
G Acids/Bases
~ Oily Waste
G Municipal Waste
G Mining Waste
G Laboratory/Hospital Waste ~ Explosives
Q Radioactive Waste	O Other
G Comtructiou/Det&oiiboQ
Waste
Physical State of Waste as Deposited (check all that
*PP»y):
G Solid G Sludge G Powder
G Liquid G Gas
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PA Guidance
EPA Region VIII
August 1993
ATTACHMENT V
PA Worksheet

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PA WORKSHEET
Site Name
CERCLIS ID #
City, State
Reported by
Date

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HIGHLIGHTS:
A) IS THERE QUALITATIVE OR QUANTITATIVE EVIDENCE OF A RELEASE TO AIR, SURFACE
WATER, GROUND WATER, OR SURFACE SOIL? DESCRIBE BRIEFLY.
More detail in items GW-1 (for GW), SW-5 (for SW), A-1 (for air), and SE-1 (for soil
exposure pathway).
B) IS THERE EVIDENCE OF AN IMPACTED TARGET POPULATION? DESCRIBE.
Pathway
Target none/target size
Brief description
More discussion in
Ground Water
public drinking
water supply
domestic drinking
water supply


Surface
Water
drinking water
fishery
sens. env.


Soil Exposure
people w/in 200'
terrestrial sens. env.


Air
population


PA Worksheet
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SITE INFORMATION
G-1. Directions to the site (from nearest easily recognized point).
G-2. Are there other potential sources in the neighborhood to be aware of as the site is evaluated?
eg. Is the site in an industrial area, near a railroad, along a highway? Are sources with similar
contaminants to this site in the vicinity?
Background/Operating History
G-3. Describe the operating history of the site:
Source of information:
G-4. Describe site and nature of operations (property size, manufacturing, waste disposal, storage
etc.):
Source of information:
G-5. Describe any emergency or remedial actions that have occurred at the site:
Source of information:
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G-6. Are there records or knowledge of accidents or spills involving site wastes? Are there
Emergency Response Notification (ERNs) reports for this location?
Source of information:
G-7. Describe existing sampling data and briefly summarize data quality (e.g. sample objective,
age/comparability, analytical methods, detection limits, QA/QC, validatability):
Source of information:
G-8. Is there any other local, state or federal regulatory involvement? Describe. Include permits,
and names of contact individuals within each government organization.
AGENCY
PROGRAM
CONTACT
PHONE
PERMIT

























G-9. Attach site sketch or schematic. Include all pertinent features including wells, storage areas,
underground storage tanks, source areas, buildings, access roads, areas of ponded water. Refer to
figure(s) submitted with text of report if appropriate.
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SOURCE CHARACTERIZATION
WC-1. Describe each source at the site, on Table 1, in terms of source type, containment,
size/area/volume/quantity, and substances present. See HRS Tables 2-5 and 5-2 for source
descriptions, Tables 3-2, 4-2, 4-8, 5-6, 6-3, and 6-9 for containment.
WC-2. Briefly describe how waste quantity was estimated (eg. historical records or manifests,
permit applications, air photo measurements, etc.):
Source of information:
WC-3. Describe any restrictions or barriers to accessibility of onsite sources.
Source of information:
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GROUND WATER CHARACTERISTICS
GW-1. Any positive or circumstantial evidence of a release to ground water? Describe.
Source of information:
GW-2. Any positive or circumstantial evidence of a release to drinking water users? Describe
analytes, detection limits, background, hits, number of users, locations, QA/QC.
Source of information:
GW-3. Briefly describe the geologic setting.
GW-4. Describe geologic/hydrogeologic units on Table 2. Give names, descriptions, and
characteristics of consolidated and unconsolidated zones beneath the site.
GW-5. Is the site in an area of karst terrain or a karst aquifer?
GW-6. Net Precipitation (per HRS section 3.1.2.2).
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SURFACE WATER CHARACTERISTICS
SW-1. Mean annual precipitation (per HRS section 4.0.2) =	. If less than 20", then count
intermittant channels as surface water.
SW-2. Discuss the probable surface water flow pattern from the site to surface waters:
Source of information:
SW-3. If surface water exists within 2 miles of the site, describe surface water segments within
the 15-mile distance limit.
Segment Name
River/
Lake/
type
Fresh/
Salt
Water
Start
(mi.)
End
(mi.)
flow
in cfs






























Ground water to surface water distance	 Angle 0
SW-4. Provide a schematic diagram or simple figure which describes surface water segments,
locates targets, identifies flow direction, PPE(s), etc. Refer to figure(s) submitted with text of
report if appropriate.
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SW-5. Any positive or circumstantial evidence of a release to surface water? Evidence of a
release by direct observation? Is the source located in surface water? Describe.
Source of information:
SW-6. Any positive or circumstantial evidence of a release to surface water target populations?
Describe analytes, detection limits, background, hits, number of users, locations, QA/QC.
Source of information:
SW-8. Is the site or portions thereof located in surface water?
Is the site located in the 1 - < 10 yr floodplain?
>10-100 yr?
>100-500 yr?
> 500 yr?
SW-9. Two-year 24-hour rainfall	
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TARGETS
T-1. Discuss ground water usage within four mile of the site:
Source of information:
T-2. Summarize the drinking water population served via Ground Water within 4 miles of the site:
0-1/4 mi 	
1/4-1/2 mi 	
1/2- 1
mi
1 - 2
mi
2-3
mi
3-4
mi
Attach calculations for population apportionment in blended systems.
T-3. Identify and locate any of the following surface water targets within 15 miles of the site:
drinking water population^) served by intakes, fisheries, sensitive environments described in Table
4-23 of the HRS, and wetlands as defined in the Federal Register.
Targets
dist.
from
site
SW body
flow
in cfs
population
served/size
(incl. units)
contaminat
ion known/
suspected






























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T-4. Summarize the population within a four-mile radius of the site:
total pod. worker pop.
onsite				
0-1/4	mi		
1/4-1/2 mi		
1/2-1 mi		
1-2	mi		
2-3	mi		
3-4	mi		
T-5. Identify and locate any terrestrial sensitive environments described in Table 5-5 of the HRS.
T-6. Describe any positive or circumstantial evidence of a release to air target populations? Of a
release by direct observation where target population exists within 1/4 mile of the site? Describe
analytes, detection limits, background, hits, number of users, locations, QA/QC.
T-7. Identify and locate any potential or known resident soil exposure populations, if present.
Describe conditions which lead the researcher to suspect contaminated soil within 200' of
residences, if this condition exists.
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TABLE 1
WASTE CONTAINMENT AND HAZARDOUS SUBSTANCE IDENTIFICATION1
SOURCE TYPE
SIZE
(Volume/Area)
ESTIMATED
WASTE QUANTITY
SPECIFIC
COMPOUNDS
CONTAINMENT1
SOURCES OF
INFORMATION






























'Use additional sheets if necessary.
'Evaluate containment of each source from the perspective of each migration pathway (e.g., ground water pathway - non-existent,
natural or synthetic liner, corroding underground storage tank; surface water - inadequate freeboard, corroding bulk tanks; air -
unstabilized slag piles, leaking drums, etc.)
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TABLE 2
HYDROGEOLOGIC INFORMATION1
STRATA NAME/DESCRIPTION
THICKNESS
(ft.)
HYDRAULIC
CON DUCTI VITY(cm/sec)
TYPE OF
DISCONTINUITY2
SOURCE OF
INFORMATION

























lUse additional sheets if necessary.
2ldentify the type of aquifer discontinuity within four-miles from the site (e.g., river, strata "pinches out", etc.)
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