WQ0003254_Regional Office Physical File Scan Up To 1/19/2021

DIVISION OF ENVIRONMENTAL MANAGEMENT
GROUNDWATERSECTION
June 19, 1990
MEMORANDUM,
TO: Don Safrit
THROUGH: Bob Cheek RU
FROM: Jack Floyd��
SUBJECT.: Duke Power Company
Cliffpide Steam Station
Ash Reuse Program
Rutherford County
WQ0003254/GW90117
The' Groundwater Section has -reviewed the subject permit
application and recommends issuance of the permit with the following
conditions:
1. No ash shall be disposed hithin 50 feet of a water supply
well.
2. No ash shall be placed within one foot of the mean seasonal
highwater table.
3. No ash shall be disposed -within 500 feet of any residence,
place of business, or place of public assembly.
These comments are being Made without regional office input.
cc:
Central Files
Permit Issuance Files
10
Groundwater Section
- I office
Asheville Rolona

Date April 5, 1990
STAFF REPORT AND RECOMMENDATIONS
County Rutherford
WQ0003254
PART I - GENERAL INFORMATION
1. Facility and Address: Duke Power Company, Cliffside Station
13.0. Box 306
Cliffside, North Carolina 28204
2. Date of Investigation: February 14, 1990
3. Report Prepared By: Jim Reid
4. Persons Contacted and Telephone Number: Wayne Beaver
704-657-6314
5. Directions. to Site: From the intersection of US Hiahwav 221A
and NCSR 1002 in Rutherford County, travel east approx 0.1 mile
on NCSR 1002 to entrance to Duke Power Company's Cliffside Steam
Station.
6. Discharge Point - Latitude: 350 13' 05"
Longitude: 81 46' 15"
Attached a USGS Map Extract and indicate treatment plant site and
discharge point on map.
USGS Quad No. or USGS Quad Name_Chesnee SC -NC t
7. Size (land available for expansion and upgrading): 100 or
greater acres
8. Topography (relationship to flood plain included): 5-10% slope
above flood plain.
9. Location of nearest dwelling: > 500 feet
10. Receiving stream or affected surface waters: Non -Discharge
a. Classifications:
b. River Basin and Subbasin No.:
C. Describe receiving :stream features and pertinent downstream
uses:

<
NON NPDE% FACILITYAND PERMIT DATA
UPDATE OPTION TRXID 5OU KEY W'0003254
PERSONAL DATA FACILITY APPLYING FOR PERMIT APP/PERMIT FEE-$ 250.00 REGION
FACILITY NAME) DUKE POWER CO-CLIFF%IDE %TAT 5 COUNTY) RUTHERFORD Oi
ADDRESS: MAILING (REQUIRED) AGINEER:
STREET: PO BOX 33189 `%TREET:
CITY: CHARLOTTE %T NC ZIP 2S241 CITY: %T ZIP O
TELEPHONE [phone] TELEPHONE:
STATE CONTACT) FLOYD . FACILITY CONTACT
TYPE OF PROJECT) SLUDGE -LAND APPLICATIONLAT: LONG:
DATE APP RCVD 03/15/90 N=NEW,M=MODIFICATION,R=REI%%UE> N
DATE ACKNOWLEDGED 03/19/90 DATE R VIEWED / / RETURN DATE
REG COMM REQ% 03/26/90 DATE D NIED / / NPDE% 0-
REG COMM RCVD / / DATE R TURNED / / TRIB Q -----�� MGD
ADD INFO REQ% / / OT AG COM REQ% 03/26/90 TRIB DATE-
ADD INFO RCVD / / OT AG COM RCVD
END %TAT APP P ^ 06/13/90 DATE I$%UED / / DATE EXPIRE
FEE CODE( )i=(>iMGD),2=()iOKGD),3=()iK D),4=((iKGD+%F),5=(%)3OOA),6=(%\=3OOA),
7=(%ENDEL),8=(%EDEL),9=(CLREC),O=(NO FEE) DISC CODES A%N/CHG PRMT
�
ENG CERT DATE / / LAST NOV DATE / / CONBILL( )
�
COMMENTS: ^
MESSAGE: *** DATA ADDED SUCCESSFULLY
� VL

PART II - DESCRIPTION OF DISCHARGE AND TREATMENT WORKS
1. Type of wastewater: _ % Domestic
Industrial
a. Volume of Wastewater:
b. Types and quantities of industrial wastewater:
Non -Discharge, land application of sludge project.
C. Prevalent toxic constituents in wastewater: None known
d. Pretreatment Program (POTWs only)
in development
should be required
approved
not needed X_
2. Production rates (industrial discharges only) in pounds
a. highest month in the last 12 months
b. highest year in last 5 years
'411
5.
C.
7.
Description of industrial process (for industries only) and
applicable CFR Part and Subpart: Electric Power Generation
Facility, 40 CFR Part 423.
Type of treatment (specify whether proposed or existing):
Proposed, various land application and non -discharge
uses of fly ash, bottom ash, and sludge from ash ponds.
Sludge handling and disposal scheme: Proposed uses of
materials include fill, soil amendment, backfill, road
bed construction, and flowable fill.
Treatment plant classification: II
SIC Code(s) 4911
Wastewater Code(s) 68

PART III - OTHER PERTINENT INFORMATION
1. Is this facility being constructed with Construction Grants Funds
(municipals only)?
2. Special monitoring requests:
3. Additional effluent limits requests:
4. Other:
PART IV - EVALUATION AND RECOMMENDATIONS Issuance of
requested non -discharge permit is recommended. In accordance
with comments contained in Mr. Roberts' letter, the
non -discharge permit should not restrict use of ash products for
road building to DOT or its contractors. Additionally, the
deletion of the buffer requirements is recommended to facilitate
ash use in building foundations and other situations where it
would be prevented by application of buffer requirements.
Condition 19 in permit No. WQ0000563 fulfills the intent of the
buffer requirements. Condition number 14 should specify "100
feet" from wells rather than "fifty feet". The permit should;
specify provisions for protection of surface waters in use of
flowable fly ash for submerged structures such as bridge or
roadway supports. Such provisions should be similar to those for
protection of waters from "live" concrete.
.3�,
ature of Report"Preparer

W�1_
_M
State of North Carolina
Department of Environment, Health, and Natural Resources
Division of Environmental Management
i% 512 North Salisbury Street • Raleigh, North Carolina 27611
James G. Martin, Governor R. Paul Wilms
W. William Cobey, Jr., Secretary Date:]9` fe'.%^ i' Director
SUBJECT Application No. WQ t° V A
Dear hirl
The Divisions Permits and Engineering Unit acknowledges receipt of your permit application and supporting
materials on A .r`. - , 19 This application has been assigned the number shown above. Please
refer to this number when making inquiries on this project.
Your project has been assigned to a4 J �� `1 �` for a detailed engineering
review. A technical acknowledgement will be forthcoming. If this acknowledgement is not received within thirty (30)
days, please contact the engineer listed above.
Be aware that the Divisions regional office, copied below, must provide recommendations from the Regional Super-
visor or a Procedure Four Evaluation for this project, prior to final action by the Division.
If you have any questions, please call the review engineer listed above at [phone].
Sincerely
Arthur Mouberry, P.E.
Supervisor, Permits and Engineering
cc: j`r y -. Regional Supervisor RECEIVED
Water Quality Section
MAR 2 9 1990
Pollution Prevention Pays
,Asheville Regional: Office
P.O. Box 27687, Raleigh, North Carolina 27611-7687 Telephone [phone] Asheville, North Carolina
An Equal Opportunity Affirmative Action Employer

Nv=':,n Carolina Department of ronment, Health, and Natural Resource _
DEM USE ONLY
Environmental Management Commission
Permit Number:
NON -DISCHARGE PERMIT APPLICATION
*in accordance with NC General Statutes Chapter 143, Article 21
County: Rutherford
Applicant (name of board, individual, or others): Application Date:
Duke Power Company 3/12/90
Project (name of city, village, town, sanitary district, establishment):
Cliffside Steam Station, Cliffaide, N. C.
FOR:
Brief Project Description:
❑ Non -Discharge Treatment/Disposal Facilities
Various projects utilizing �ponded bottom asl
and fly ash for electric utility coal com-
❑ Pretreatment Facilities
bustion. Projects may include structural
❑ Sewer Collection System (private)
fills, flowable fills, road base material,
❑ Extension of Sewer Systems (public),
bedding material, soil amenaent and a
U Sludge Disposal
drainage material.
❑ Spray Irrigation
NATURE OF WASTEWATER:
❑ Domestic Sewage
Sludge/Industrial Waste
Estimated Completion Date: N/A
❑ Other Waste
From (sewers, pretreatment plant): Serving (city, institution, industry):
Ash disposal pond. Cliffside Steam Station
Into (name of treatment plant): Average Daily Gallons Sewage or Waste Flow:
Various land application projects. N/A
At (location of plant): (NPDES No.)
Projects iiray be located in any N. C. county. NCOO N/A
Name and Complete Duke Power Company i - 28242
Address of Engineering Firm: ' Zip Code:
P. 0. Box 38189 � 704/� ^73-6133
Telephone No:
Charlotte, NC (Ralph Ca Roberts)
Applicant assures that proposed works will be constructed, supervised, operated and maintained In accordance
with approved plans and specifications or approved changes thereto.
Mailing Duke Power Company
Print Name: M. D. McIntosh Address: Fossil Production Department
P. 0. Box 33189
Title: V. P. Fossil Production Zip Code: 28242
-, -' Signature: � - Telephone No. / 704 373-5941/
INSTRUCTIONS:
1.Fill-in All Spaces. If not applicable, enter N/A.
2.Secure appropriate signature (mayor/city manager for municipality, chairman for sanitary district board, owner/proper official of
corporation, or legally constituted board or commission in charge of proposed works). A letter of authorization is required from
proper official if design engineer or other agent signs application.
3.Submit to Division of Environmental Management, Permits and Engineering Unit, P.O. Box 27687, Raleigh, NC.27611 the original
and ALL carbon copies of the application, 3 sets of finalized plans, specifications and other supporting data as required by Com-
mission uuies, and permit tee. Plans and specifications must be signed and sealed by a registered North.Carolina engineer
FOR ASSISTANCE, CALL THE STATE CENTRAL OFFICE [phone], PERMITS & ENGINEERING• UNIT, OR:
Asheville [phone]
Mooresville [phone]
Washington [phone]
Winston-Salem [phone]
59 Woodfin Street
919 North Main Street
1424 Carolina Avenue
8025 N. Point Blvd.
P.O. Box 370
P.O. Box 950
P.O. Box 1507
..Suite 100
Asheville, NC 28801
Mooresville, NC 28115
Washington,NC 27889
Winston-Salem, NC 27106
i
Fayetteville [phone]
Raleigh [phone]
Wilmington [phone]
Suite 7114 Wachovia Building
3800 Barrett Drive
7225 Wrightsville Avenue -
Fayetteville, NC 28301
P.O. Box 27687
Wilmington, NC 28403
Raleigh, NC 27611

Duke Power CompanY [phone]
/nssil Production DepurtnuvN
P.O. lio.r 3. i 189
-i°_' So wh C."mr (h street
March 12, 1990
Mr. Donald Safrit
North Carolina Department of Environment,
Health, and Natural Resources
Division of Environmental Management
Permits and Engineering Unit
P. 0. Box 27687
Raleigh, North Carolina 27611
Subject: Allen Steam Station
Cliffside Steam Station
Dan River Steam Station
Ash Reuse Permits
Files: AS-704.15, CS-704.15, DR-704.15
Dear Mr. Safrit:
Enclosed are three Non -Discharge Permit applications for Duke Power Company's
Allen, Cliffside and Dan River Steam Stations. These stations are located in
Gaston, Rutherford and Rockingham counties, respectively. The goal is to have
general permits which would allow the recycling of ponded bottom ash and fly
ash in a variety of applications,. while allowing quick response to customer
ash demand. Permits similar to what we are requesting were issued last year
for Riverbend and Marshall Steam Stations.
Typical land applications for ash reuse include structural fill, flowable
fill, road base material, bedding material under pipes and concrete, soil
amendment and as drainage material. Projects may be located anywhere in North
Carolina where economics allow. For background information the following docu-
ments are attached:
1) Four papers describing ash reuse by industry and a glossary of terms.
2) A letter to the Mooresville Regional Office of NCDNRCD dated February 9,
1989 which describes some of the typical land application reuses of ash
Duke Power expects to be involved with and the controls to prevent the
ash from leaving the site.
3) A copy of the Marshall Steam Station ash reuse permit.
4) Test data for ponded ash.
Precautionary measures will be implemented to prevent recycled ash from
leaving the application area and adversely impacting the environment or
adjacent property owners. All uses of ash (except some NCDOT use of bottom ash
and soil amendment) will be promptly covered with soil, pavement or structures
t

Mr. Donald Safrit
March 12, 1990
Paqe two
T'
T
MAR 5 i990
after ash placement, which prevents ash from leaving the sMA, ^in some
applications, such as flowable fill, the ash is mixed1with a
cement) which prevents migration of ash off site.
C
To prevent aeolian transport of ash off site during the construction phase of
a project, the ash surface will be kept moist. Trucks hauling ash to the site
will be covered and the ash will also have adequate moisture content (15% to
25%) to prevent dusting.
Transport of ash off site by water runoff during the construction phase of a
project will be prevented by using sedimentation ponds, silt fences, ditches,
etc. as required in properly designed erosion control plans.
The permits for Allen, Cliffside and Dan River Steam Stations are requested to
be similar to the Marshall permit except with the following modifications:
Condition 7 - Restricts ash use on roads to NCDOT or its contractor.
Private road owners or developers and other governmental agencies
should be allowed to utilize bottom ash for their own road construc-
tion or maintenance.
Condition 17 - The buffer requirements on condition 17 effectively
prevent the recycling of pond ash, and unless they are eliminated
from the new permits the potential success of the ash recycling
program will be greatly diminished. The buffers are designed to
protect adjacent property owners from ash migration. This can be
achieved without buffers; some of the methods have been previously
discussed. Preventing ash migration is required by permit condition
19, and is the responsibility of the permit holder. The buffers do
not provide significant additional environmental protection, but do
assign the right to prevent a project, for non -environmental rea-
sons, to adjacent property owners.
Condition 20 - Soil amendment is a beneficial and environmentally
safe use for recycled pond ash and its addition to the 'list of
authorized uses should be considered. The enclosed paper from EPRI
provides some information on this use.
Thank you for your help in recycling a valuable resource and saving limited
disposal space. The $750 application fee for the three permits is enclosed. If
you have any questions, please call me at [phone].
Very truly yours,
7
Ralph C. Roberts
Fossil Environmental Compliance
RCR:mp
Enclosures

'
AUG a 91988
�. 11A lu 11tS 6, 1988
- J
000
i Pr- aivilT
Memo to: Frank Burn
EC - 1090
Design Engineering
subject: Results of F.iverbend Dredge Pond Ash
Hazardous Waste Characterization
Attache(J are th= results of the hazardous waste
characterization that you requested on the 2 waste
samples. All results were less than the EPA limits unless
otherwise indicated. All tests -were performed using
approved EPA or ASTM methods as referenced in the manual
Test M=t_hods for Evaluating solid Wastes: Physical/Chemical
Methods(EPA 1982). If you have any questions concerning this
data, my number is 875-5227.
cc: T. Whisenant
T. Bowlin,-
,9 u✓� Sc,u=-� C-�x
��i ndy Knox n/" �s �
�i �X,L i�'r! /rsTs

1
HAZARDOUS WASTE CHARACTERIZATION RESULTS
RIVERSEND DREDGE POND ASH
W.C.. #: 88-08-047
SAMPLE I.D.>
#2-0 FT.
#7-8 FT.
EPA LIMITS)
FRACTIC-N #>
01
02
RESULTS
AG
<
0.04
<
0.04
5.0
AS
0.2
0.28
5.0
BA
1.1
0.75
100.0
CD
<
0.004
0.018
1.0
CR
<
0.03
<
0.03
5.0
HG
0.022
<
0.01
0.2
PE
<
0.08
<
0.08
5.0
SE
<
0.2
<
0.2
1.0
ALL METAL RESULT'S
ARE
IN MG/L
pH
N,2,T
REQUIRED
< 2, > 12
All samples were non-flammable

L
HAZARDOUS WASTE CHARACTERIZATION RESULTS
RIVERSEND DREDGE POND ASH
W.C.. #: 88-08-047
SAMPLE I.D.:-
#11-8 FT.
#12-0 FT.
EPA LIMITS
FRACTION #>
03
04
RESULTS
AG
<
0.04
<
0.04
5.0
A53
0..3
0.39
5.0 '
BA
0.73
0.76
100.0
CD
<
0.004
<
0.004
1.0
CR
<
0.03
<
0.03
5.0
HG
<
0.01
<
0.01
0.2
PB
<
0.08
<
0.08
5.0
SE
<
0.2
<
0.2
1.0
ALL METAL RESULTS
ARE
IN MG/L
pH
NOT
REQUIRED
< 2, > 12
All samples were non-flammable

Memo to: Frank Burns
Design Engineer
EC - logo
RE�:''IVE•-
_-"iV;1Z!0,�
E P 1 0 198aep t emt er
ivibloN USE
::i N f TO FILE
l NO.
Subject: Results of Mineralogy Test
Riverbend Dredge Pond Ash
Q
14, 1988
Listed below are the results
of the mineralogy test performed
on the ash
from Riverbend
Steam
Station. The ash
digested using
ASTM method #D3682-78(Major
was
and Minor Elements
in Coal and
Coke Ash by Atomic Absorption)
and
analyzed= -for
aluminum, calcium,
iron, magnesium,
potassium, sodium,
silicon, and
titanium. The
sample
was digested using a
slight modification
of the
Chemical
Sciences
Procedure #
PESEC/6.6 and
analyzed using PESEC/6.5
for total phosphorus
determination.
Sulfur content(by
%)
was determined using
procedure #CFL
105.
SAMPLE I.D.>
#2-0 FT.
#7-8 FT.
#11-8 FT.
#12-0 FT.
PARAMETERS
ALUMINUM MG/G
153
152
165
158.
%
15.3
15.2
16.5
15.8
CALCIUM MG/G
10
8.4
8.6
9.7
%
IRON MG/G
1.0
46
0.84
0.86
0.97
53
64
82
4.6
5.3
6.4
8.2
POTASSIUM MG/G
29
28
30
29
%
2.9
2.8
3.0
2.9
MAGNESIUM MG/G
8.5
6.9
7.3
7.7
0.85
0.69
0.73
0.77
SODIUM MG/G
3.5
3.5
4.0
3.5
%
0..35
0.35
0.40
0.35
SILICON MG/G
224
221
251
245
%
22.4
22.1
25.1
24.5
TITANIUM MG/G
8.0
8.4
9.4
9.3
%
0.80
0.84
0.94
0.93
PHOSPHORUS MG/G
0.56
0.63
0.65
0.71
0.056
0.063
0.065
0.071
SULFUR %
0.02
0.06
0.07
0.04
If you need additional
information
or have
any questions, I
can be reached at 875-5227.
' /�
Cindy Knox
cc: T. Whisenant
T. Howling

a pwr
MAR
n
State of North Carolina - 1.
Department of Natural Resources and Community Development
Division of Environmental Management
512 North Salisbury Street • Raleigh, North Carolina 27611
James G. Martin, Governor R. Paul Wilms
William W. Cobey, Jr., Secretary March 13, 1989 Director
Mr. Ralph Roberts
Duke Power Company
Fossil Production Department
P.O. Box 33189
Charlotte, N.C. 28242
SUBJECT: Permit No. WQ0000563
Marshall Steam Station
Ash Reuse Program
Catawba County
Dear Mr. Roberts:
In accordance with your application received October 3, 1988, we are
forwarding herewith Permit No. WQ0000563, dated March 13, 1989, to the Duke Power
Company for the continued operation of the subject ash reuse program.
This permit shall be effective from the date of issuance until February 28,
1994, shall void Permit No. 10667R1, and shall be subject to the conditions and
limitations as -specified therein.
If any parts, requirements, or limitations contained in this permit are
unacceptable to you, you have the right to request an adjudicatory hearing upon
written request within 30 days following receipt of this permit. This request must
be in the form of a written petition, conforming to Chapter 150B of North Carolina
General Statutes, and filed with the Office of Administrative Hearings, Post Office
Drawer 11666, Raleigh, North Carolina 27604. Unless such demands are made this
permit shall be final and binding.
If you need additional information concerning this matter, please contact Mr.
Jack Floyd, telephone No. 919/733-5083.•
Sincer y,
R. Paul Wilms
cc: Catawba County Health Department
Mooresville Regional Supervisor
Groundwater
P.O. Box 27687, Raleigh, North Carolina 27611-7687 Telephone [phone]
An Equal Opportunity Affirmative Action Employer

NORTH CAROLINA
ENVIRONMENTAL MANAGEMENT COMMISSION
DEPARTMENT OF NATURAL RESOURCES AND COMMUNITY DEVELOPMENT
RALEIGH
P E R M I T
For the discharge of -Sewage, Industrial Wastes, or Other Wastes
In accordance with the provisions of Article 21 of Chapter 143, General Statutes
of North Carolina as amended, and other applicable Laws, Rules, and Regulations
PERMISSION IS HEREBY GRANTED TO
Duke Power Company
Catawba County
FOR THE
construction and operation of an ash reuse program to utilize fly ash and bott
yom ash
from the Marshall Steam Station for the purposes as listed in condition No. 2 ith
no discharge of the wastes to the surface waters, pursuant to the app ' tion
received September 14, 1988, and in conformity with the project plan,
specifications, and other supporting data subsequently filed and approved by the
Department of Natural Resources and Community Development and considered a part of
this permit.
This permit shall be effective from the date of issuance until February 28, 1994,
shall void permit no. 10667R1, and shall be subject to the following specified
conditions and limitations:
1. This permit shall become voidable unless the facilities are constructed in
accordance with the approved plans, specifications, and other supporting data.
2. This permit is effective only with respect to the nature and volume of wastes
described in the application and other supporting data.
3. The facilities. shall be properly maintained and operated at all times.
4. This permit is not transferable.
5. In the event that the facilities fail to perform satisfactorily, including the
creation of nuisance conditions, the Permittee shall take such immediate
corrective action as may be required by this Division, including the construction
of additional or replacement wastewater treatment or disposal facilities.
6. This permit may be rescinded unless the reuse program is carried out in a manner
which will protect the assigned water quality and groundwater quality standard.

7. All ash utilization on roadways shall be performed by the N.C. Department of
Transportation or its contractor.
8. Ash shall not be applied in inclement weather or until 24 hours following a
rainfall event of 1/2 inch or greater in 24 hours.
9. The Permittee, at least six (6) months prior to the expiration of this permit,
shall request its extension.. Upon receipt of the request, the Commission will
review the adequacy of the facilities described therein, and if warranted, will
extend the Permit for such period of time and under such conditions and
limitations as it may deem appropriate.
10. The facilities shall be effectively maintained and operated as a non -discharge
system to prevent the discharge of any wastewater resulting from the operation of
this facility.
11. The issuance of this permit shall not relieve the Permittee of the responsibility
for damages to surface or groundwaters resulting from the operation of this
facility.
12. No ash except that from the Marshall Steam Station shall be used in this program.
13. Adequate records of the ash use program shall be maintained by the permittee.
These records -shall include but are not necessarily limited to the following:
a. date of ash application,
b. type of ash used,
c. type of application,
d. volume of ash applied in tons,
e. location of use, and
f. ash receiver.
These records shall be summarized monthly and submitted to the Mooresville
Regional Supervisor annually on or before January 31 of the following year.
14. No ash shall be placed within fifty feet of any water supply well.
15. No ash shall be placed within one foot of the mean season high water table.
16. The permittee shall provide an ash analysis -to all users.
17. The following buffers shall be maintained:
a. 500 feet between application area and any residence, place of business, or
place of public assembly, unless permission is first obtained.
b. 100 feet between application area and any stream, creek, lake, pond or
other natural drainageway or other surface water body.
C. 100 feet between application area and property lines unless permission is
first obtained from adjacent property owners.

18. Any monitoring deemed necessary by the Division of Environmental Management to
insure surface and ground water protection will be established and an acceptable
sampling reporting schedule shall be followed.
19. Adequate provisions shall be taken to prevent wind erosion and surface runoff
from conveying pollutants from the ash application area onto the adjacent
property or into the surface waters.
20. The following uses of ash are hereby authorized:
a. Fly ash and bottom ash may be used for structural fills such as roadway
embankments and foundations, industrial and residential construction
foundations.
b. Fly ash may be used for flowable fills such as cement and brick mixtures,
backfill materials around water, sewer and storm drain piping.
C. Bottom ash may be used for secondary road overlay and snow and ice control,
drainage material and pipe bedding for railroad beds and underground storage
tanks, and septic drain fields.
21. Issuance of this permit shall void Permit No. 10667R1.
Permit issued this the 13th day of March, 1989.
NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION
R. Paul Wilms, Director
Division of Environmental Management
By Authority of the Environmental Management Commission
Permit No. WQO000563

Engineer's Certification
1, , as a duly registered Professional
Engineer in the State of North Carolina, having been authorized to observe
(periodically/weekly/full time) the construction of the project,
U
(Project)
(Name or Location)
for the
hereby state that, to the best of my
(Project Owner)
abilities, due care and diligence was used in the observation of the project
construction. such that the construction was observed to be built within substantial
compliance and intent of the approved plans and specifications.
Signature
Date
Permit No. WQ0000563
Registration No.

AMERICAN COAL'ASH ASSOCIATION, INC.
GLOSSARY:
Terms related to the annual survey of coal consumption and coal
ash produced and utilized/consumed.
Agriculture -- Soil amendment, other than mine spoil amendment
(See also: Mining Industry/Surface Reclamation), for changing
physical and/or chemical characteristics of the soil to improve
crop yield.
Aggregate --. Lightweight aggregate manufactured from coal fly
ash. Normal -weight aggregate manufactured from scrubber sludge.
Bottom ash or boiler slag used as a fine aggregate.
Backfills -- Use of moisture -conditioned fly ash or bottom ash as
an alternative to imported borrow for filling trenches, volumes
behind retaining walls, and miscellaneous excavations.'
Blasting Grit -- Use of boiler slag as substitute for sand or
oxide -abrasives in cleaning of castings, paint removal,,etc.
Boiler Slag -- Hard, glassy coal ash particles collected from wet
bottom, or cyclone furnaces. when molten by-product materials
flowing from the furnaces is quenched in water baths.
Bottom Ash -- Solid particles of coal combustion by-products
which -are collected at the bottom of dry bottom furnaces.
Coal Type -- Anthracite, bituminous, subbituminous and lignite.
Concrete Block -- Use of fly ash for a portion of.the cementious
material, and/or use of bottom ash as a substitute for sand and
other fine graded aggregates in the manfuacture of building
blocks.
Embankments -- Use of coal combustion by-products as a structural
fill above grade for carrying a roadway or a building, or for
gravity dam construction.
FGD Sludge -- Flue_ gas desulfurization sludge (see Scrubber
Sludge),.
Fly Ash Class.-- Fly ash as defined by ASTM C-618, Class C or F.
Filler in Asphalt -- Use of fly ash in bituminous concrete
mixtures to compensate for deficient fines in the aggregate being
used, or to impart other physical characteristics.

Fillers
Filler in Coatings -- Use of fly ash as a substitute for
various minerals in the manufacture of coatings.
Filler in Metals -- Use of fly ash as a substitute for
various alloy materials.
Filler in Paints -- Use of fly ash as a substitute for
titanium dioxide, calcium carbonate, zinc phosphate, etc.,
in the manufacture of paints.
Filler in Plastics -- Use of fly ash as a substitute for
glass, ceramics,'talc, limestone, and sintered clays in the
manufacture of plastics.
Flowable Fill -- Use of fly ash with water as a backfill-type
material, achieving compressive strengths of 1,200 psi or less;
also containing, in varying proportions, portland cement and
aggregate, as appropriate (See also: Mining Industry/Underground
Grouting; oil & Gas Industry). The generic term for this type of
material, as described.by Committee 229 of the American Concrete
Institute, is Controlled Low Strength Material.(CLSM).
Mining Industry -
Surface Reclamation -- Use of fly ash in landfill
applications"to restore surface mining areas to original or
desirable contours; or to amend mine spoil materials.
Underground Grouting -- Use of.fly ash in a flowable fill
(see above) to correct subsidence conditions or to control
mine fires.
Miscellaneous/Other -- Use of coal combustion by-products in
ballast, slurry, walls, chemical manufacture and mineral recovery,
etc.
Oil.& Gas Industry -- Use of fly ash with water and Appropriate
admixtures for grouting and closing wells.
Pavement Bases -- Use of fly ash with various activators in
pozzolanic stabilized mixtures in the construction of highways,
airport runways, parking lots and haul -roads on Federal lands.
Portland Cement -- Use of fly ash by a cement manufacturer:
-- as a raw material. feedstock to the kiln in the
production of portland cement clinker; or
-- as an additive to portland cement for the production of.
blended cements.
2

Ready Mixed Concrete and Precast Concrete --*Use of fly_ ash'as'a
mineral admixture to improve characteristics of fresh and
hardened concrete, such as strength, and resistance to alkali -
aggregate reactivity and sulfate attack; and to decrease costs of
concrete production.
Real Estate Development -- Use of coal combustion by-products in
a landfill -type application to improve the topography, especially
for, but not limited to, commercial and residential building
construction.
Reefs -- Use of precast fly ash concrete specifically in the
construction of reefs as breakwaters and as habitats for water
life.
Respondent -- Preparer of ACAA Survey Form.
Roofing Granules -- Use of boiler slag as an inert substitute for
screened fine aggregates in asphalt shingles.
Scrubber Sludge -- Lime or powdered limestone combined with
sulfur products, collected from the flue gas stream of.coal-fired
furnaces by means of wet or dry scrubbers.
Short Ton -- A unit of weight equal to 2,000 pounds, contrasted
with a long ton of 2,240 pounds and a metric ton of 2,205 pounds.
Snow and Ice Control -- Use of bottom ash as an alternative to
sand for road de-icing operations.
Soil Amendment -- See Agriculture.
Soil Modification -- Any change to in -place soils that results
in immediate effects that can expidate highway pavement
construction operations. These changes can be measured in terms
of moisture' reduction, improved California Bearing Ratio (CBR)
values.and/or decrease in plasticity.
Soil Stabilization -- A permanent change to in -place soils that
makes significant improvements in the soil mixture
characteristics resulting in "higher type" subgrades for highway
pavements. Unlike soil modification, stabilized soils for
pavement subgrades can be assigned structural support values as
an intergal part of the pavement structure. The several
activities that should be monitered closely include mixture
proportioning, quality control and construction procedures, as
well as the in -situ strength verification of the stabilized soil
layer.
KI

Structural- Fills -- Use of coal' -by-products in.a'
landfill -type applita.tion to improve the.topography,- especially
for, but not limited to, commercial and residential building
construction (See also Embankments).
Utilization -External Market Consumption -- Consumption of coal
combustion by-products by end -users other than the producing
company or its affiliates.
Utilization -Internal Utility Consumption -- Consumption of coal
combustion by-products by the producing company or its
affiliates.
Wallboard -- Use of scrubber sludge with a satisfactory gypsum
(calcium sulfate) content in the manufacture of building panels.
Waste Stabilization/Modification
Hazardous -Waste Stabilization -- Use of fly ash interblended
with lime and soils containing such materials as heavy
metals, organics, or oils to chemically fixate contaminants
into a cementitious matrix. -
Non -Hazardous Waste .Modification -- Use. of fly ash
interblended with municipal waste sludges to reduce water
content, to provide physical stability, and to prevent
erosion and leaching.
FGD Sludge Solidification -- Use of fly ash interblended
with flue gas desulfurization sludge and lime to produce a
hardenable, cementitious product for environmentally safe
disposal.
Zero -Percent Moisture -- Coal combustion by-products produced and
handled in a manner not requiring or allowing the addition of
moisture may be assumed to contain 0%moisture.. Coal combustion
by-products for which the production and handling require or
allow added moisture will require a computation to adjust the
weight of the moist material to a weight containing 0% moisture.
4

ATTACHMENT 2
Need a Dependable Backfill - Try Flowable Fly Ash -
Joseph J. Funston, 1 M. ASCE and William C. Kre11,.2 F. ASCE _
Introduction
Flowable fly ash is a relatively new cementitious structural
backfill material. It can be used.in water or in the dry and will
flow into place without the,usual labor-intensive activities of
spreading, rolling, and compacting. Its properties are described and
illustrated.through the use of short case histories and results of
testing.
Background
Flowable fly ash is a cement stabilized backf ill material. It is
composed of fly ash and a small amount of cement, usually 5 percent by
the dry weight of -the ash, and enough water- to provide the desired
flowability or consistency for the; application at hand. This normally
means a slump of 8 to 10 inches (203 to 250 mm) when filling confined
areas and a slump of 5 to 6.5 inches (127 to 165 mm) when constructing
embankments.
Fly ash is a by-product from the generation of electricity at
modern power plants which burn coal. It is the very fine, light dust
which is removed from the stack gas stream and collected by the air
emissions control equipment. Fly ash is readily available in quantity
from coal burning utilities. It'ranks in the top six by weight of
minerals and fuels produced yearly in the United States following
stone, sand/gravel, coal, iron ore,, and Portland cement. It can be
obtained directly from producing power plants or as a recoverable
resource from the many existing ash storage sites.
Flowable fly ash came into being out of a desire to use fly ash
to construct a three track wide railroad embankment in water up to 30
feet (9m) deep (Funston, Krell, Zimmer, 1984). A trial program in
1979 proved that it could be done but the railroad project was
cancelled. Since then it has been used in a wide variety of
applications both in water and on land.
1. Soil Mechanics and Foundation Engineer, Detroit Edison Co.,
2000 Second - 356 ECT Detroit, MI 48226
2. Staff Civil Engineer, Detroit Edison Co.,
2000 Second --356 ECT, Detroit MI-48226
1 Funston-Krell

The material is somewhat unique in its handling characteristics
and the chemical composition of the fly ash and cement will vary with
the area of the country. Therefore the contractor and supplier should
allow for some experimentation to develop a feel for the flowable ash.
It should be noted that all of the fly -ash used in the work described
in this paper is that obtained from the burning of bituminous coal.
Ashes obtained from the burning of sub -bituminous coal and lignite are
also widely available. Ashes from all of Detroit Edison's plants with
carbon contents ranging from 4 to 12 percent have been used in
producing this backfill product.
Figure 1. Flowable Ash Being Placed In 10 Feet (3m) of Water
In the Detroit area it has been successfully produced in a wide
range of consistencies in pug mills, concrete batch plants, and
turbine type mixers. It has been transported in concrete ready -mix
trucks, conventional open bed trucks, and on conveyors. It has been
placed by chuting, pumping, end dumping, and directly off of
conveyors. The compression strength will generally be above 100 psi
(690 kPa) at 28 days based on tests using 2-inch (51 mm) cubes.
Although the material appears to be.very.forgiving from the standpoint
of precise moisture and temperature requirements, proper measuring,
mixing, delivery, and placing procedures should be followed to
maintain the quality required for a specific application. Some short
case histories and results -of testing will now be given to illustrate
a variety of properties and applications.
2 Funston-Krell

20�
(6m)
FLOWABLE FLY ASH
PLACED DIRECTLY INTO WATER
Figure 2.- Trial Embankment Construction In Water
Figure 2 is a cross section through a small peninsula 160 feet
(50 m) long, built in 1979 as part of a pilot program to verify
construction feasibility for its initial use in the now postponed
railroad embankment. Not only was constructability proven but a
number of other exciting characteristics were noted:
(a) The material could be end -dumped out of open trucks or dozed into
the water and still stay together in a mass.
(b) The angle of repose was steep, 2 plus vertical to 1 horizontal.
(c) The material exhibited erosion resistance when placed in .flowing
water.
(d) The material could be driven on by the following day and
sometimes sooner.
(e) A degree of flexural beam strength was indicated when a portion
of the embankment was undercut resulting in a cantilever
condition.'
Test pits dug in the flowable fly ash several months later had
sides that were straight, hard, and free of voids. The resulting
embankment was as strong or stronger than any that could have been
built in the dry using conventional materials placed in layers and
compacted at near optimum moisture.
3 Funston-Krell

Figure 3. Structural Backfill For Foundation Support
A telephone company was adding some air conditioning equipment at
one of their `major office complexes. The equipment was supported
above grade on five concrete walls. Figure 3 shows the construction
of these walls. The design called for the backfill to be placed and
compacted in -layers.' This was done on two of the walls over a one
week period. Realizing the saving in schedule the contractor opted for
flowable fly ash on the last three walls, backfilling them all on one
Saturday morning with'no labor involved.
4 Funston-Krell

C__1
286 TON
, (2545 k N )
CRANE
PLOWABLE FLYASH
FILL 1.5' (. 5 m) ± THICK
Figure 4. Structural Support of Construction Equipment
A contractor was constructing a multistoried apartment and hotel
complex consisting of precast concrete elements on.'a tight schedule in
the downtown area of a major city. As shown in Figure-4 a -runway had
to be built from 1 to 3 feet (.3 to 1 m) thick and 200 feet'(61 m)
long over a rubble strewn terrain to support the erection crane. The
use of flowable fly ash permitted a quick installation in a limited
access area and eliminated the need for regrading during the
construction period which the use of conventional fill materials would
have required.
5 Funston-Krell

CONCRETE WALL PLACED
AGAINST NEAT CUT IN
FLOWABLE FLY ASH FILL
Figure 5. Use As Formwork and Support In Caving Soils
On this same project the subcontract for the grade foundation
walls called for placement against a neat excavation. As it turned
out most of the site consisted of old basements that had been
backfilled with brick and rubble. During excavation these would fall
in resulting in a much wider hole than anticipated. The conventional
approach to this problem would have involved a contract change calling
for the walls 'to be formed and the placement .of compacted fill after
the forms were stripped. However a solution that was beneficial both
to schedule and cost was at hand and was used. Flowable fly ash was
rapidly placed in the oversized trenches. On the following day the
neat excavation for concrete placement was accomplished as shown in
Figure 5 and the walls constructed as per original contract.
6 Funston-Krell

EW SLAB
■
FLOWABLE
FLY ASH FILL_
Figure 6. Structural Fill of Pits Containing Debris
An auto company decided to renovate, modify, and reuse an old
production building which they had abandoned for several years.
Figure 6 depicts one of a number of pits containing assorted debris
which needed to be filled to permit the placing of a grade slab to
match the adjoining areas. The pits .varied in size and were up to 25
feet (7.6 m) deep, 8 feet (2.4 m)' wide, and 50 feet (15 m) in length.
In addition to saving time the use of flowable fly ash removed- the
need.for.going into the pits prior to placing the backfill. The
debris that would float came to the top and was removed at -that time.
That which did not float was encapsulated in the ash and posed no
problem to bearing capacity.
7 Funston-Krell

FILL POINTS
250' ( 76 m ) +
C TO C
r,RAnF
v % - . . ..., - , - . 1 11 L
Figure 7. Structural Fill of Underground Enclosures
A natural use for the flowable fly ash is the filling of
abandoned below grade enclosures such as storage tanks, tunnels, and
sewers. Figure 7 illustrates the filling of a sewer pipe at the site
of a new automotive facility. In this instance the fill points were
spaced about 250 feet (76 m) apart along the length of the pipe.
Before being used for placing the fly ash they served as vents for the
displaced air ,and as a way -of monitoring the progress of the fill down
the pipe. Experience has indicated that there is no set method of
placing the material, venting, and monitoring for these types of
backfill projects. Some time for experimentation and latitude for
change should be included in the schedule.
8 Funston-Krell

j FLOWABLE
FLY ASH FILL
Figure 8. Settlement -free Backfill Around Buried Pipes
Another common use of flowable fly ash as shown in Figure 8 has
been that of bedding and encasing underground pipes. When
conventional backfill materials are used the trench must be wide
enough or sloped back to make room for equipment to compact the fill
and allow for inspection. When a roadway is involved, in spite of
good intentions on the part of engineer and contractor, conventional
fills often continue to -consolidate after thepavement is replaced and
cracks or dips in the road show.up at a later date. Here the use of
flowable fly ash does away with future settlement problems and could
result in a reduction in the amount of excavation and subsequent
backfill. Inspection costs are also minimized.
9 Funston-Krell

RANDOM SITE FILL
FLOWABLE
FLY ASH FILL
9.5 (3m)
0. D_ CONC.
PIPES
Figure 9. Cost Savings At Multiple Large Pipe Installation
The use of flowable fly ash around pipes on a major installation
can result in significant savings. Its use around the circulating
water lines at Detroit Edison's Belle River Plant shown in Figure 9
has been described previously (Narang, Funston, 1983; Funston, Krell,
Zimmer, 1984). The trench was about 1 mile (1.6 km) long. Savings of
close to $1 million were effected in a number of ways:
(a) The pipes could be placed closer together and the amount of
excavation and backfill reduced.
(b) The flowable fly ash had a lower unit cost in place than the
other structural fill materials at this site.
(c) With conventional earthfills the engineer would have asked for
the grouting of each joint to protect the exposed steel. With
the encasement of flowable fly ash this requirement was
eliminated since the ash was basic in nature similar to
concrete.
(d) The schedule for this portion of project was shortened.
10 Funston—Krell

Recent Testing Results
During the course of some of the projects mentioned under the
case histories, foundation designers requested information on the
modulus of subgrade reaction, or subgrade modulus, of the flowable fly -
ash to aid them in their soil/structure interaction foundation
analysis. A small research program was undertaken to determine the
subgrade modulus for different age samples and to develop an empirical
correlation between the subgrade modulus and standard laboratory
tests. (Bird, 1984).
A placement approximately 16 x 26 feet (5 x 6 m) in plan and
2-feet (.6m) thick was made in an excavation to provide for the field
testing. A cement content of 5 percent and a slump of 10 inches
(254 mm) were reported. Field plate bearing tests were run at 3, 7,
and 28 days. A 1.95-inch (50 mm) diameter plate (field CBR piston)
was -used for the 3-day test to measure the value of the subgrade
modulus. Both this plate and a 13.5-inch diameter plate were used for
the 7 and 28 day tests.
At the time of placing, 2-inch (51 mm) cubes and 3 x 6-inch
(76 x 152 mm) cylinders, 9 of each, were molded for the laboratory
testing. Unconfined compression tests were run at 3, 7, and 28 days to
correlate with the field testing.
The results of this testing program indicate that the unconfined
compressive strength (Qu) of 2-inch (5 cm) cubes is a -useful indicator
of the modulus of subgrade reaction (K) for a one square foot (.09 m2)
area plate on the flowable fly ash. The recommended relationship is:
K = 50 x Qu, with K in pci and Qu, in psi. In addition, the
unconfined compressive strength of the 3 x 6-inch (7.6 x 15 cm)
cylinders was found to be an excellent indicator of the modulus of
elasticity (E) by the relationship: E = 180 x Qu, where E and Qu are
in consistent units. Additionally, the K value determined by the use
of a field CBR piston was found to be approximately twice that of the
K for a one square foot (.09 m2) area.plate.
The flowable fly ash had on occassion given the indication of
possessing a degree of flexural strength. To confirm this a series of
beam tests were run (Krell, 1985). The material used was the same as
that placed for the plate load tests. Two standard beam forms,
normally used to test paving concrete, were filled from the ready -mix
truck at the mixing plant just prior to making the delivery to the
plate load test site. The beams were nominally 6 inches (152 mm)
square and 40 inches (.34 m) long.
The two specimens were left unattended at the mixing plant for
about 3 weeks with only a light covering of plastic. They were then
transported to Edison's laboratory and permitted to dry out at room
temperature. Several days before testing one beam was wet down so
that there would be two moisture conditions to compare. Testing took
place at 165 days of age. After the flexual testing was complete
several 5-inch (127 mm) cubes were cut from the remaining pieces and
tested in compression at 178 days. The following is a summary of this
testing.
11 Funston-Krell

Moisture Compressive Modulus
Content Strength of Rupture
psi (kPa) psi (kPa)
0.6 413 (2846) 170 (1171)
10.0 279 (1960) 215 (1480)
Note that the average compressive strength for the 2-inch (51 mm)
cubes at 28 days from the plate load test program was 290 psi (1998
kPa).
Although the findings on the subgrade modulus and modulus of
rupture were of necessity based on a small number of tests, the
results indicate that the flowable fly ash possesses significant
strengths in both respects. Testing for other properties is now
underway. cinder the sponsorship of the Electric Power Researh
Institute the determination of freeze -thaw, wet -dry, shrinkage,
capillarity, and permeability characteristics will be included in this
program. This information will be useful in the design of roadways,
embankments, bridge approaches, light weight fills, dikes, and
reservoirs-. Results are expected to'be available during the coming
year.
Figure 10. Flowable Fly Ash Being Chuted Into Place
12 Funston-Krell

Conclusion
Flowable fly ash is a cement stabilized backfill material that
flows into place either in water or on land. It provides properties
,that are significantly better than those of conventional structural
backfill materials. It becomes economically competitive wherever a
structural well -compacted fill is required. As contractors and
engineers become familiar with this relatively new product, they are
coming up with a variety of ways to put it to use. Current testing
should enhance this growth in utilization.
Appendix - References
Bird, D.W., "Modulus of Subgrade Reaction Testing," Report to Detroit
Edison, SME Project No. 7574, August 1984.
Funston, J.J., Krell, W.C., and Zimmer, F.V., "Flowable Fly Ash: A
New Cement Stabilized Backfill," Civil Engineering Magazine, ASCE,
March, 1984.
Krell, W.C., "Flowable Fly Ash Flexural Test," Internal Report -
Detroit Edison, January, 1985.
Narang, R.P. and Funston J.J., "Innovations Cut Costs of a Power
Plants Water System," Civil Engineering Magazine, ASCE, July, 1983.
13 Funston-Krell

Duke Power C,mpum 704) 3,73-40/l
Fossil Production Departmen(,__�
P 0. Box .,mis.9
422.5outh Church Street
Charlotte. N.C. 28242
February 9, 1989
Mr. J. Thurman Horne, P.E.
North Carolina Department of Natural Resources
and Community Development
P. 0. Box 950
Mooresville, North Carolina 28115
Subject: Ash Reuse Permits
Marshall Steam Station - WQ0000563
Riverbend Steam Station - WQ0000452
Files: MS-704.15; RB-704.15
Dear Mr.. Horne:
This letter provides information concerning the possible uses of ash and the
precautions to be implemented which will prevent its release to the surface
water -.environment, as we discussed in our meeting on February 3, 1989. Also
included as attachments, are specific examples of ash use and an ash reuse
permit -issued by NCDEM to -Carolina Power and Light Company. The following
information is for land application uses of ash:
1., Structural Fills - Ash is a lightweight, inexpensive fill material which
can be used to improve load bearing capacity of soils and to level uneven
terrain. The ash used can be'flyash and/or bottom ash. The ash is
-spread in lifts at a designed moisture content and rate of compaction.
Typical uses for filled sites include roadway embankments, recreation
areas and commercial, industrial and residential construction.
To prevent the loss of ash offsite or to surface water bodies during
construction of the structural fill, all runoff shall be routed to
sedimentation basins. Silt barriers shall be installed and maintained
.along the fill boundary and properly designed ditches shall be provided
along all slopes to insure the integrity of•the slope and prevent the
movement of ash.
Upon completion of the structural fill it shall be covered with soil; a
minimum depth of 6 inches on horizontal surfaces and 2 feet on slopes
greater than 5%. A cover depth of 2 feet shall be required on fills for
residential development and no soil cover is required for areas -to be
promptly covered with asphalt -,.concrete or building structures.. The soil
cover shall not contain rocks larger than 12 inches maximum dimension,
excessively wet soil, logs, brush or roots larger than 1 inch diameter,
sod or perishable material.

Mr. J. Thurman Horne, P.E.
February 9, 1989
Page two
After placement of the
and seeded with grass.
uniform stand of grass
soil cover, the fill' shall be promptly fertilized
Any area which fails to produce and maintain a
shall be reseeded.
Ash shall not be placed closer than 50 feet to surface water. In special
cases where the ash is placed within 50 feet of surface waters the NCDEM
Regional Office will be provided project details that ensure protection
of the surface waters.
To prevent the loss of ash during transport all trucks hauling ash shall
be covered and the ash shall have an adequate moisture content (15%-to
25%) .
2. Flowable Fills - Flyash is mixed with water and small percentages of
cement and aggregate and slurried into place. The American Concrete
Institute calls this a controlled low strength material, achieving a
compressive strength of 1200 psi or less.
Primary application is as backfill around water, sewer and storm drain
pipelines and retaining structures.
To prevent -any impact to the surface water the flowable fi11'shall be
covered with a minimum of 6 inches of soil on -.horizontal surfaces and 2
feet on slopes greater than 5%, unless covered with asphalt or concrete.
All areas with a soil cover shall be promptly.fertilized 'and seeded with
grass.
3. Road Base and Subgrade Stabilization - Flyash can be used in the base and
subbase courses of roadways and parking lots and foundation subgrades.
It is mixed with the on -site soils or in combination with lime'and/or
cement.
This application of ash is always covered with asphalt, concrete or a
structure. It shall not be placed closer than 50 feet to surface waters.
4. The existing permit adequately addresses controls for D.O.T. use of
bottom ash for secondary road overlay and snow and ice control.
5. Drainage Material, Pipe Bedding and Dry Bed Material , Bottom ash has
been used extensively as a bedding and drainage material. It is easily
placed and free draining.
Possible uses include sub ballast for railroads, backfill around under-
ground storage tanks and piping and where permitted, septic drain fields.
Precautions to.protect the environment include a soil ,'.concrete -or
asphalt cover -as described for structural fills or a stone cover for the
railroad application. These applications.will also not Ibe placed within
50 feet of surface water.

3
Mr. J. Thurman Horne, P.E.
February 9, 1989
Page three
Hopefully the information provided in this letter and the attachments will
help in completing your review of our permit request.
If you have any questions, please call me at [phone].
Sincerely,
Ra-lph C. Roberts -
Fossil Environmental Compliance
RCR:mp
Attachments
bcc: J. 0. Fayssoua
B. K. Sipe
C. E. Brown
L. S. Harper

POWER PLANT ASH UTILIZATION
The burning of coal to help supply the nation's
electrical needs produces power plant ash, the nation's
fourth most abundant resource. Each power plant produces
distinct ash products suitable for different uses. Utility
plants produce fly ash, bottom ash and boiler slag. The
type of ash produced depends upon the type of boiler used,
the specific type of coal burned, and the type of ash
handling facilities available.
Past projects that have utilized power plant ash
nationwide have helped earn commercial and governmental
acceptance on the use of ash as a construction material.
Power plant ash has been used for 30.years in power plant
construction in dams, cooling towers, plant roads, etc.
Chemical and physical tests are conducted on the ash on a
routine basis to insure the ash meets all_ASTM standards and
any associated environmental requirements. ..
Fly ash may be handled -through a silo where moisture is
added for hauling and placing in a disposal area. The
alternative method is to store the ash in a lagoon through a
wet system. This method produces a product referred to as
ponded ash and is the source ofmaterial for large
construction projects which require large daily tonnages.

Bottom ash is normally handled by a wet system for
storing the ash in a lagoon where it is very readily
recovered for end use projects. The alternative to the wet
system is dewatering bins.
Fly Ash
Fly ash is a powdery material made up of .tiny separate
glass spheres. Chemically, fly ash consists primarily of
silica, alumina, iron"oxide and calcium oxide. Fly ash is
the primary type of ash produced (80% of ash production) and
has more of an identity in reuse applications.
o Cement Replacement in Concrete -. The most common
application for fly ash is as a partial replacement
for cement in ready -mix concrete and concrete
products. By replacinga portion of.the cement in
a mix, raw material costs are reduced, while the
strength and quality of concrete are improved.
o Structural Fills - Fly ash is a lightweight,
inexpensive fill,material. By using..fly ash
as a structural fill material, poor load -bearing
soils and uneven terrain can be converted into
valuable property. The ash is spread -in lifts
at the proper moisture content and compacted to
95% of standard proctor density. Large structures,
shopping malls and housing developments ,have been
constructed on fly ash fills.
_2_

o Road Base - Fly ash has been used as a base material
by combining with a bi.^.der such as cement or lime in
many states and in•private construction. Several
states now have specifications in place for this
application.
Dry Bottom Ash
Dry bottom ash is a coarse, granular material that
falls to the bottom of the power .plant furnaces during the
combustion process. As America's natural resources are
consumed in greater quantities, the need for a quality,
inexpensive aggregate becomes obvious. Bottom ash is a free
draining aggregate with consistent,gradations and has a low
unit weight.
o Drainage Media - By nature, bottom ash has excellent
drainage capabilities. It is equally effective as
natural aggregates, yet lightweight and less costly.
o Pipe Bedding and Dry Bed Material - Bottom ash has
been used extensively as a bedding material. Because
of the ease in placing this material around pipes and
under concrete slabs, this application has become the
largest use for bottom ash. The material can be
end damped and spread with an end loader or dozer or
by hand and compacted by rollers or tampers to the
required density. Because bottom ash is a free
draining material, additional moisture is required in
the field.
-3-

o Snow and Ice Control - Bottom ash replaces natural
aggregates in many states as an ice and snow
abrasive. The advantages besides price are ash
particles absorb the sun's rays to help melt snow
and ice, the material does not freeze in the stock-
pile, and the weight/volume relationships for bottom
ash allows the material to go further than natural
materials.
o Base Material - Many miles of cement treated bottom
ash have been placed in the country as base material
in the secondary and primary system. The active use
presently is in widening projects. The major advan-
tage is that the bottom ash on a tonnage basis goes
further than limestone or other aggregates because of
it being lightweight, thus major savings per mile in
highway construction. Many times the highway
contractor sets up equipment on power plant property,
thus saving the front end hauling costs.
-4-

Section 1
INTRODUCTION AND SUMMARY
The Electric Power Research Institute (EPRI) has initiated an ash utilization
research, development and demonstration program aimed at supporting the increased
use of fly ash in the United States. This program has been divided into three
principal areas:
• High -volume uses
• Medium -technology uses
• High-technology uses
High -volume uses include those fly ash products which are either large in quantity
or use high percentages (over 50 percent) of fly ash in the product. In addition,
these products must not require'a specified type or quality of fly ash, but must
satisfy only performance specifications. Hig`,-volume uses are typified by fills,
embankments, backfills, base courses, soil stabilization, soil amendment and
grouts. Medium -technology uses are defined as those uses which require the fly
ash to satisfy a specific specification, i.e., ASTM C618-83, and typically involve
only a small percentage (5-20 percent) of the product produced. Medium -technology
uses include cement pozzolans and bituminous fillers. High-technology uses are
currently directed at the extraction of metals, i.e., aluminum, iron, titanium and
silver from the fly ash. This report covers only high -volume uses of fly ash.
This area of ash utilization appears to have the highest probability of
dramatically increasing fly ash utilization in the short term due to its potential
to consume ash regardless of its physical, engineering and chemical properties.
The use of fly ash as a high -volume construction material is mandatory to increas-
ing ash utilization in the United States. In general, the use of fly ash for
fills, embankments, backfills, base courses, soil stabilization, soil amendment
and grouts is technically justified. In fact, fly ash is considered a typical
construction material in some countries. However, the use of fly ash for these
applications has been restrained in the United States for many reasons. One major
reason, and possibly the dominant one, is the presence of abundant and relatively
inexpensive virgin building materials in the United States.
1-1

DEFINITIONS OF HIGH -VOLUME PROJECTS
There are 2 basic ways to utilize fly ash produced from coal-fired electric
generating stations:
• Ina dry or slightly moistened state
• In a slurried or flowable state
In the first type of application, fly ash is either removed dry from the silo and
pneumatically transferred to a tank -type truck or it is conditioned with water
(approximately 20 percent moisture by weight) and placed in an open -type dumping
truck. In the slurried or flowable state, the fly ash is blended with enough
water so that it can be pumped into place similar to grouting applications.
Dry or Conditioned Fly Ash Placement
The dry or conditioned state is defined as Conditioned Ash Placement. This
category has been subdivided into eight sections:
• Backfills
• Embankments
• Fills
• Landfill Cover
• Pavement Base Course
• Soil Amendment
• Subgrade Stabilization
• Waste Stabilization
Slurried or Flowable Fly Ash Placement
The slurried or flowable state has been subdivided into four sections:
• Backfills
• Grouts
• Hydraulic Fills
• Embankments
1-3

The remaining projects were subgrade stabilization (7), landfill cover (1), soil
amendment (6), waste stabilization (3) and backfills (2). Therefore, the appli-
cations with established design and construction experience are fills, embankments
and LFA base courses. The remaining applications have fewer design and construc-
tion examples available.
Grouts comprised 21 of the 31 slurried -or flowable 'applications. Over 1,000,000
tons of fly ash have been placed into abandoned mine caverns, primarily in West
Virginia. Detroit Edison Company has developed a procedure for using flowable
cement -stabilized fly ash as a backfill. Four backfills were, placed by Detroit
Edison Company. There is only 1 example of a hydraulic fill and 1 example of a
flowable embankment.
One significant fact is that 126 of the 172 Class F.projects are 1,000 tons or
over and 24 of these are 100,000 tons or over. Therefore, the use of Class F fly
ash in high -volume applications is well' -established.
Class C Fly Ash Applications
There are 108 Class C fly ash applications identified. One hundred and two of
these projects utilized ash in 4 conditioned or dry state and 6 were placed as
Slurries.
Class C fly ash has a much higher content of lime than Class F fly ash. This
property, along with the pozzolanic nature of the fly ash, creates a material that
self -hardens when water is added. This property results in the fly ash developing
compressive strength similar to Class F fly ash stabilized with cement. Of
course, in most cases there is no need to'stabilize Class-C fly ash. It is more
common to experience situations in which -the ash hardens too quickly if it is not
Continually mixed and maintained in a slurried state. Retardents have been devel-
oped that slow the setting time of the fly ash allowing more time between
preparation of the slurry and placement.
The largest application of Class C fly ash is for subgrade stabilization.
Pavement base courses (13), embankments '(5), fills (4), backfills (3) and waste
stabilization (4) are.the next largest uses of Class C fly ash in a dry or condi-
tioned.state. Only 3 backfills and 3 grouts- were documented as slurried or
flowable applications and no hydraulic 'filIIs are listed.
1-5

Section 2
TYPES OF PROJECTS INVESTIGATED
PURPOSE OF PROGRAM
The EPRI fly ash utilization program covers most known uses for fly ash in various
levels of technology. Some of these categories are shown on Table 2-1. This
project is designed to focus exclusively on the high -volume applications. High-
technology applications, such as metal extraction, and medium -technology applica-
tions, such as cement and concrete products, are included under separate EPRI
projects and are specifically excluded from this report. Examples of high -volume
applications are site fills, grouts and roadway subgrade stabilization. The ob-
jective of this project is to document as many different high -volume uses for fly
ash as can be found. Resources used to document projects included literature
surveys, telephone surveys, mail surveys and site visits. The survey methods are
described in detail in Appendix A. A list of individuals who supplied information
for this project is contained in Appendix C.
As discussed above, the purpose of the overall program for which this report was
prepared is to promote the use of fly ash in high -volume uses. One of the driving
forces for this project is the relatively low percentage of fly ash that is cur-
rently utilized. Figure 2-1 shows the quantity of fly ash produced and utilized
in each of the 9 EPRI regions in 1984. As the disposal costs for fly ash in-
crease, high -volume utilization becomes more attractive. In some areas of the
country where Class C fly ash is produced, the ash is valuable as a lime substi-
tute and roadbase material. This use is preferable to disposal and can become a
profitable alternative. The highest percentage of fly ash utilization occurred in
Region 1 where 35 percent of the total.ash produced was utilized. However, only
285,000 tons of fly ash were produced in this region, the smallest total of all 9
regions. In those regions with an ash production exceeding 5 million tons per
year, the highest percentage of utilization (28 percent) was in Region 7.
Approximately 80 percent of the fly ash produced in 1984 was not utilized, and a
significant amount of fly ash is available for high -volume projects.
2-1

N
1
W
A-1.
U-0.
11
A = FLY ASH PRODUCED
U - FLY ASH UTILIZED
(tons x 106 )
�A= 5.26
O{ U— 0.91
io►-9.91 ,- 2
L A-5.37 f� U-1.5711
U— 1.13
6�
A-5.2
A-6.46 l r
U-1.81 (`
J-�
t
.r
A-12.17
- . ^.37
Figure 2-1. Fly Ash Production and Utilization by EPRI Region
Source: American Coal Ash Association
A-0.28
U-0.10

procure coal from more distant sources because of air quality limitations.
Generally, bituminous coals, producing a Class F fly ash, are burned east of the
Mississippi River and subbituminous coal and lignite, producing a Class C fly ash,
are burned west of the Mississippi River. One notable exception is the four cor-
ners region in Arizona, Colorado, New Mexico and Utah where some utilities burn
local bituminous coal. Projects using Class C and Class F fly ashes are distribu-
ted according to the areas that burn specific coals. This report includes
projects that utilized both classes of fly ash.
DESCRIPTION OF UTILIZATION PROJECTS
There are 2 basic ways to utilize fly ash produced from coal-fired electric --
generating stations:
1. In a dry or conditioned state
2. In a slurried or flowable state
In the first type of application, fly ash is either removed dry from the ash silo
and pneumatically transferred to a tank -type truck or it is conditioned with water
(approximately 20 percent moisture by weight) and placed in an open -type dumping
truck. In the flowable or slurried state, the fly ash is blended with enough
water so that it can be pumped into place similar to grouting applications. The
following subsections describe typical types of projects for both of these appli-
cations.
The dry or conditioned state is defined as Conditioned Ash Placement. This
category has been subdivided into eight applications as follows:
1. BACKFILLS - These projects are usually small fills placed in
restricted areas behind retaining walls or in trenches. Because of
the restricted area compaction is likely to be performed by hand
tampers or other small equipment.
2. EMBANKMENTS - These are fills placed for use as support for
highways and railroads or as, dams to impound water. Embankments
usually have an exposed slope face where slope stability is an
important consideration.
3. FILLS - These projects are large area or site fills as opposed to
embankments or backfills. Fly ash is placed with larger trucks,
dozers and self-propelled compaction equipment.
4. LANDFILL COVER - In these projects, ash is used as a surficial fill
over other materials. An example is using fly ash as daily cover
for municipal wastes in lieu of soil.
2-5

Fill Applications
Fill applications include backfills, embankments and site fills. Historically,
the utilization of fly ash as a fill material has been a direct result of its
light unit weight, high strength, low compressibility and relative economy when
compared to natural borrow material. The light unit weight is particularly advan-
tageous in situations where filling is necessary on relatively weak and
compressible subsoils. The use of natural materials, which have dry unit weights
on the order of 100-130 ponds per cubic foot, can produce excessive settlement on
a compressible subsoil or, conceivably, complete failure of the weak, underlying
strata. The average range of compacted dry unit weights for fly ash, 70-95 pounds
per cubic foot, represents a considerable reduction in the surcharge placed on
these in -place materials. This is not to preclude the use of fly ash on suitable
subsoil. In general, where there is a lack of suitable borrow materials near the
construction site, fly ash from a nearby power plant can represent an economic
source of borrow material.
The use of fly ash as a fill material can be broken down into four general
categories:
1. Backfills for bridge abutments and utility trenches
2. Roadway embankments
3. Site development fills
4. Repair or stabilization of landslides
Backfills. Fly ash or cement -fly ash mixtures can be used as a replacement for
well -graded sandy gravel or other backfill materials in bridge abutment back -
fills. The advantage of fly ash in this application is low compressibility and a
lower unit weight than natural materials and thus, a reduction in lateral loads on
the abutment. Other potential advantages include reduced material cost and a
source of low moisture content borrow for use during periods of wet or freezing
weather.
A Portland cement -fly ash mix can also be used in lieu of earth for pipe
backfills. Advantages of fly ash in this application are high strength and low
compressibility.
2-7

and protective layer for synthetic liners. The spherical nature of the fly ash
particles are often less likely to abrade the liner than other materials.
Pavement Base Course
Fly ash is used in roadway and parking lot pavements because of its pozzolanic
properties which can be used to strengthen the pavement at a relatively low
cost. Fly ash is normally used as a constituent of the base and subbase
courses. Fly ash is not used as the surface course (the roadway surface) because
of its friability (i.e., where it is subject to abrasion and surface erosion).
d -
Fly ash as a part of base or subbase courses can be used in the following three
principal ways:
1. In combination with lime and/or Portland cement and coarse
aggregate
2. In combination with Portland cement alone or lime alone
3. In combination with the on -site soils with or without the inclusion
of lime
Lime, plus fly ash, plus coarse aggregate, is called LFA and when Portland cement
is used, LCFA. Fly ash plus Portland cement alone is called CFA. These three
materials are used as an alternate to a full depth asphalt base course, an all
aggregate base course. The overall approach is to use the LFA as a component in a
flexible pavement system, typically as a base course and sometimes as a subbase
course. As with all paving materials, LFA and LCFA are most effective when used
under proper conditions and within specified limitations. LFA and LCFA materials
can be used for a wide range of pavement systems from low -volume roads to heavy-
duty pavements. These materials can be used as either base or as subbase
materials in flexible pavement systems. A wearing surface is required. The wear-
ing surface can vary from a seal coat for low -volume roads to 4 to 6 inches of
asphalt concrete for heavy-duty pavements.
The use of Portland cement stabilized fly ash (CFA), without the inclusion of
coarse aggregate, can provide an excellent base course material. As with LFA or
LCFA, attention to proper conditions and limitations is essential to effective
performance. Those conditions listed for LFA and LCFA also apply to a CFA fly ash
base course. An asphalt wearing surface is used in conjunction with the CFA base
course.
2-9

moved by heavy equipment. This phenomenon, known as "puddling", occurs due to
compaction and compression of soil in the moist state. The collapse of the soil
structure due to the compaction reduces the capability of the soil to allow water
to infiltrate, especially after the soil has dried. By blending fly ash with the
puddled soil, pore space is increased and surface crusting is diminished, thereby
allowing water to enter the soil.
This increase in pore space is additionally beneficial in areas where soil
moisture is at a premium. As additional porosity is available, the soil can hold
more water and nutrients for plant consumption. The increase in subsurface poros-
ity also permits deeper root penetration, thereby allowing plants to seek deep
soil moisture previously unavailable to them.
Subgrade Stabilization
Subgrade stabilization, sometimes termed soil stabilization, generally refers to
the physical and/or chemical methods used to improve natural soils or soil -
aggregates for use in some engineering applications. Soil stabilization is used
predominantly in the construction of roadways, parking areas, runways and founda-
tions. Soil stabilization can eliminate the need for expensive borrow materials,
expedite construction by improving particularly wet or unstable subgrade, effect
savings in pavement thicknesses by improving subgrade conditions and permit the
substitution in the pavement cross-section of low cost materials for conventional
and more costly materials.
As a result of the low cost of fly ash and its excellent pozzolanic properties,
there are many cases in which lime -fly ash stabilization is more advantageous than
lime or Portland cement stabilization. Depending on the soil type, lime -fly ash
stabilization can produce greater strengths and improved durability when compared
to lime stabilization. In locations where lime is cheaper than Portland cement,
lime -fly ash stabilization can often produce material of comparable long-term
strength and durability at a reduced cost when compared to Portland cement
stabilization.
As indicated previously, stabilization of soils with fly ash alone is still in the
developmental stages, although it shows promise of becoming a yery effective and
economical technique. This method is most successful when fly ash with self -
hardening properties is used due to the typically high free -lime content. This
free -lime produces favorable changes in the properties of several soil types and,
2-11

• Reduce compressibility
• Fill undesirable voids in the formation being grouted
Fly ash has many properties which make its use in grouts for such purposes very
attractive. Among these properties are'its particle shape and size, gradation,
specific gravity, low, heat of hydration and-pozzolanic activity.. These properties
are discussed briefly below.
Particle Shape. The fineness of particle size and the predominantly spherical
shape of fly .ash particles enables grouts incorporating fly -ash to be pumped more
easily than those containing only Portland cement or sand. The spherical shape"
results in a ball -bearing effect which enhances the flow properties of the
grout. Partial replacement of either Portland cement or sand by fly ash improves
pumpability and injection by keeping the grout in suspension and thus reducing
sedimentation.
Specific Gravity. The specific gravity of fly'as.h-generally varies between 2.1
gm/cm3 and 2.6 gm/cm3 which is lower than that for Portland cement (3.15 gm/cm3)
or sand (2.7 gm/cm3). This is often advantageous where weight is a critical, fac-
tor. In addition, sedimentation is reduced because of the low unit weight.
Gradation. Fly ash particles are mainly of silt size, but fly ash also contains a
small but significant percentage of finer clay -sized material. Although the coef-
ficient of uniformity is low, these clay -sized particles provide sufficient
grading to -reduce segregation during pumping and injection and result in lower
voids and increased .durability of the grout when placed.
Pozzolanic Activity. The pozzolanic properties of fly ash enable it to combine
with Iime.to produce a stable cementitious material. Since the hydration of
Portland cement also produces lime. additional. cementation results when fly ash is
added to Portland cement. This reaction provides a more effective. bond tham that
between sand and Portland cement in weak Portland cement grouts.
Fly ash contains a certain amount of water-soluble sulfate. However, the
pozzolanic reaction- between fly ash and.lime released during the,hydration of
Portland cement has been shown to actually increase the sulfate -resistance of.a
Portland cement grout.
2-13

Section 3
EXISTING PROJECTS
From the surveys and site visits discussed in Section 2, 278 separate projects
were identified that used fly ash in high -volume applications., These projects are
listed in Appendix B, Table B-1. Table 3-1 summarizes the various types of appli-
catibns'and the number of projects identified for each application.
Table 3-1
HIGH -VOLUME PROJECTS IDENTIFIED FROM SURVEYS
Application No. of Projects
Dry or Conditioned Ash Placement
1.
Backfi11
5
2.
Embankment
29
3.
Fill
29
4..
Landfill Cover
7
5.
Pavement Base Course
79
6.
Soil Amendment
6
7.
Subgrade Stabilization
80
8.
Waste Stabilization
7
Subtotal
Slurried or Flowable Ash Placement
Projects Over
1,000 Tons
4
25
25
6
49
4
22
7
RT
1..
Backfills
11
6
2.
Embankment
1
1
3.
Grout
23
22
4.
Hydraulic Fills
1
1
Subtotals
36
30
Total
278
172
3-1

w
i
w
Table 3-2
PROJECTS FOR WHICH FLY ASH WAS USED AS A CONDITIONED BACKFILL
Rank
Size
Class
1
10,500 cu. yds.
C
2
5,658 tons
F
3
3,500 tons
C
4
1,000 tons
C
5
Unknown
F
Description
Channel at Black Dog
Station
State Route 7 Bridge
Farmland Industries
Kroh Brothers Parking
Garage
Retaining Wall
Location
Burnsville, MN
Powhattan Point, OH
Kansas City, MO
Kansas City, MO
Eastlake, OH
Utility
Northern States Power
Ohio Edison
Kansas City Power & Light
Kansas City Power & Light
Cleveland Electric
Illuminating `

Landfill Cover
The use of fly ash for daily cover in landfills is a relatively recent application
and is limited to projects from New England Electric System except for one experi-
mental program conducted at the Morgantown, WV landfill by Allegheny Power Service
Corporation, the City of Morgantown and West Virginia University. The 5 largest
projects are listed in Table 3-5. All of these projects utilized fly ash from New
England Electric System. Since much of the borrow material locally available is
sandy and more permeable than fly ash, the use of fly ash reduces the amount of
infiltration into the landfill, thereby reducing leachate production. At most of
these sites, fly ash is also used as the final cover. For several of the projects
a synthetic membrane was required to further limit infiltration of rainfall. -Fly
ash serves as a good liner base and protective cover on the liner prior to placing
the final topsoil for revegetation.
The projects listed on Table 3-5 range in size from 14,000 to 160,000 tons.
Therefore, the procedures for using fly ash for landfill cover are well estab-
lished for large tonnage uses.
Pavement Base Course
Fly ash has been widely used as an additive to pavement base course materials.
The most widely used application is as an additive to lime -fly ash -aggregate (LFA)
base courses. In LFA mixes fly ash comprises 5 to 40 percent of the base course
depending on the other components of the mix and the desired strength of the
base. The primary objective of this project is to promote the use of cement -fly
ash in base course applications where fly ash comprises of at least 80 percent of
the mix. Both Class F and Class C fly ashes have been used as pavement base
courses. When Class F fly ash is used, 5 to 10 percent cement must be added to
stabilize the ash. When Class C fly ash is used, up to 100 percent fly ash can be
used, depending upon the free -lime content of the fly ash.
There are 79 pavement base course applications identified in Table 3-1. Only 11
of the 79 projects can be classified as high -volume applications in which fly ash
comprised over 75 percent of the base course. The 5 largest projects are listed
in Table 3-6. The largest project was a "homemade rock" roadbase constructed in
Amarillo, Texas as were the second and fourth -largest projects.- The homemade rock
process is discussed in Section 2. The third -largest project used 20,000 tons of
3-5

Table 3-5
THE FIVE LARGEST PROJECTS WHERE FLY ASH WAS USED AS A LANDFILL COVER
Rank
Size
1
160,000
tons
2
100,000
tons
V
3
80,000
tons
4
45,000
tons
5 14,000 tons
Class
F
F
F
F
F
Description Location
Capuano Brothers Landfill Cranston, RI
Municipal Landfill Somerset, MA
Norton Municipal Landfill Norton, MA
State Landfill Johnston, RI
Swansea Municipal Landfill Swansea, MA
Utility
New England Electric
New England Electric
New England Electric
New England Electric
New England Electric

Rank Size
1 78,000 tons
w
2 23,756 tons
3 20,000 tons
4 17,000 tons
5 5,525 tons
Table 3-6
THE FIVE LARGEST HIGH -VOLUME APPLICATIONS Or FLY ASH IN PAVEMENT BASE COURSES
Class
Description
C
Hommart Corp.
Mall
Parking Lot
C
Petro Truck Stop
C
Unidentified
road
C
Grand Central
Store
Parking Lot
F
Bikeway
Location
Amarillo, TX
Amarillo, TX
Velva, NO
Amarillo, TX
Montgomery County, OH
Utility
Southwestern Public
Service
Southwestern Public
Service
Basin Electric
Southwestern Public
Service
Dayton Power & Light

Subgrade Stabilization
There were a total of 80 projects identified where fly ash was used to stabilize
subgrades. In the majority of these cases, fly ash was used to reduce the plas-
ticity and increase the shear strength of soils on small commercial building sites
so that construction equipment could be moved onto the site quickly, often the
same day. Of the 80 projects, only 22 are known to be 1,000 tons or over. The 5
largest projects are shown in Table 3-8. Three of these projects are for highway
subgrades and 1 involves soil stabilization for taxiways, aprons and buildings at
an airport. Three of these applications involved Class C fly ash and 2 used
Class F fly ash.
Waste Stabilization
Seven projects were identified in which fly ash was used to stabilize pond or
sludge wastes. Six of these projects involved industrial wastes and 1 involved
municipal sewage sludge. Four projects used Class C fly ash and 3 used Class F
fly ash. All of the projects used 1,000 tons or more of fly ash. The 5 largest
projects are listed in Table 3-9. Since most of these projects involve
proprietary or sensitive information, detaile� information on the type of waste
could not be obtained. It is likely that there are many more applications in -
place; however, many of the project owners prefer not to publicize the locations
and other relevant data.
SLURRIED OR FLOWABLE ASH PLACEMENT
Backfi11s
Slurries of Class C fly ash or flowable cement -stabilized Class F fly ash have
been used to backfill trenches and around concrete foundation footings. As shown
in Table 3-1, a total of 11 backfills have been documented. Six of these applica-
tions are 1,000 tons or over and have been documented. The 5 largest applications
of flowable ash backfills are listed in Table 3-10. Four of the 5 largest
applications used the flowable ash concept developed by Detroit Edison Company.
Flowable ash is Class F fly ash stabilized with cement, usually 5 percent, to
produce a low -strength fill (100-300 pounds per square inch unconfined compres-
sion) that does not require compaction. This results in a backfill that has more
3-11

Table 3-9
THE FIVE LARGEST PROJECTS WHERE FLY ASH WAS USED FOR WASTE STABILIZATION
Rank
Size
Class
Description
Location
1
27,000
tons/year
C
DuPont Industrial Waste
Tecumseh, KS
Stabilization
2
30,000
tons
F
Rollins Environmental
Pleasantville, NJ
Industrial Waste
Stabilization
3
10,000
tons
C
Waste Management
Furley, KS
Industrial Waste
Stabilization
4
8,000
tons
C
Mobil Oil Co.
Augusta, KS
Industrial Waste
Stabilization
5
1,500
tons
F
Chem -Dyne Industrial
Cincinnati, OH
Waste Stabilization
0
Utility
Kansas Power & Light
Atlantic City Electric
Kansas Power & Light
Kansas Power & Light
Cincinnati Gas & Electric

w
U1
Table 3-10
THE FIVE
LARGEST
APPLICATIONS OF SLURRIED
AND FLOWABLE FLY ASH
USED AS BACKFILL
Rank
Size
Class
Description
Location
Utility
1
270,000
cu. yds.
F
Trench Backfill for
St. Clair, MI
Detroit
Edison
Circulating Water Lines
2
36,000
cu. yds.-
F
General Motors Poletown
Poletown, MI
Detroit
Edison
Foundation Backfill
3
20,000
tons
C
Trench Backfill for Water
Ferris, OK
Oklahoma
Gas & Electric
Pipe
4
17,000
cu. yds.
F
Millender Center Founda-
Detroit, MI
Detroit
Edison
tion Backfill
5
3,000
tons
F
Toys "R" Us Foundation
Taylor, MI
Detroit
Edison
Backfillj

r r�
I
FmhnnL--f+
The cement -stabilized Class F fly ash described above can also be used to place
embankments directly into water. This was done by Detroit Edison Company as an
experimental project near Monroe, Michigan. The embankment was intended to sup-
port a railroad spur. While the spur has not been constructed, the first segment
of the embankment is in place and in good condition.
HIGHLIGHTED PROJECTS
A number of the projects that are well documented are summarized in brochure
formats. These projects are representative of most of the different types of the
uti.lization applications discussed in this report. The summaries contain
information on the properties of the fly ash used, design procedures, construction
methods and performance and also include photographs. The brochures are contained
in Appendix D.
3-17