ML19350E689

Revised Process Control Program.

ML19350E689
Person / Time
Site:	Beaver Valley
Issue date:	05/31/1981
From:	DUQUESNE LIGHT CO.
To:
Shared Package
ML19350E687	List: ML19350E686 ML19350E688 ML19350E689
References
PROC-810531, TAC-8132, NUDOCS 8106230444
Download: ML19350E689 (31)

Text

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O DUQUESNE LIGHT COMPAhT Beaver Valley Power Station Docket No. 50-334

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PROCESS CONTROL PROGRAM March, 1979 Revised: May, 1979 Revised: May, 1981 q

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• TABLE OF CONTENTS PAGE I. PURPOSE . . . . . . . . . . . . . . . . . . . . . . . 1 II. SOLID WASTE DISPOSAL SYSTEM DESCRIPTION . . . . . . . 2 A. FUNCTION . . . . . . . - . . . . . . . . . . . . . 2 B.

SUMMARY

OF SYSTEM OPERATIONS . . . . . . . . . . 2 III. OPERATIONS PERFOPJ1ED TO VERIFY SOLIDIFICATION OF RESni WASTES . . . . . . . . . . . . . . . . . . . 5 A. FEED RATE CONTROL . . . . . . . . . . . . . . . . 5

3. OPERATOR FOLLOW . . . . . . . . . . . . . . . . 7 C. FINAL DTSPECTION . . . . . . . . . . . . . . . . 7 4 IV. OPERATIONS PERFOPJ1ED TO VIRITY SOLIDITICATION -

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A. BORIC ACID CONCENTRATION . . . . . . . . . . . . . . . . . 9

3. FEED RATE CONTROL . . . . . . . . . . . . . . . . 9

- C. OPERATOR FOLLOW . . . . . . . . . . . . . . . . . 10 D. FINAL INSPECTION . . . . . . .. . . . . . . . . . 11 tI . DISPOSAL OF SOLID OBJECTS Di CONCPITE LDIERS. . . . . 12 VI. CRITICAL ITEMS LIST . . . . . . . . . . . . . . . . . 13 VII. LD1ITATIONS AND SURVEILLANCE P2QUIREMENTS . . . . .- . 16

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A. LIMITATIONS . . . . . . . . . . . . . . . . . . . 16

3. SURVEILLANCE P2CUIP2MENTS . . . . . . . . . . . . 16 APPENDIX A - CEM9 fT SOLIDI?ICATION TESTS WITE RESDI AND EVAPORATOR EOTTOM WASTI

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SOLUTIONS. . . . . . . . . . . . . . . . . . 20

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I. -PURPOSE e

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1. To-provide appropriate radwaste system feed rates

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necessary to achieve the waste to cement ratios .re-

. quired to assure solidification of liquid radioactive wastes.- -

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2. To crovide results of tests' performed to determine the

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waste to cement ratio required for solidification of the radioactive wastes (evaporater bottoms, boric acid and spent resins) generated at Heaver Valley. These results form the basis for set points indicated in Chapter 13 (Solid Waste Dis.cosal Svstem) of . tie Un'it 1 Operating

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Manual.

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3. To indicate the rec.uirements for disc.osal of radicactive

• filter cartridges, rags and other solid obj ects in the

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matrix of the solidifie,d. concrete.

4. To indicate critical set points and limitations-for opera-tion of the radwaste solidification system.

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5. To indicate surveillance requirements for solidified

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- II.. SOLID WASTE DISPOSAL SYSTEM DESCRDTION

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A. FUNCTION .

The Solid Waste Disposal System (SWS) is designed to provide holdup, packaging, and storage facilities Ccr the eventual off-site shipment and ultimate disposal of radioactive waste =aterial. Liquid wastes are in=cbilized in a concrete matrix using a ATcon solifification system provided for this purpose. A facility is also-provided to wash shipping containers after leading to prevent release of activity to the environment.

3 B.

SUMMARY

OF SYSTEM OPERATIONS The waste solidification system consists of a' cement '

storage bin, cement feeder, mixer-feeder, resin waste

p. hold tank, evaporador bottoms hold tank, resin hold and bottoms hold tank feed pumps, and the necessary piping, valves and instruments for the system to function. chis equipment is used to immobilize the following wastes:

^; (1) spent resin, (2) concentrated liquid wastes, and.(3) solid wastes such as filter cartridges and polyethylene bags containing contaminated rags or other radioactive debris. Solid wastes are contained.within an open-mesh

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metal basket located in the approximate center of the concrete liner. The basket is suspended off the bottom so that the concrete mixture will totally surround the basket.

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Wastes are solidified in a carbon steel 1iner which has a total capacity of approximately 65 cubic feet with usable capacity of about 60 cubic feet. This liner J is moved into positien under the mixer-feeder by 2

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transfer cart through remote control operation. Where b . - solid waste disposal is involved',1the metal basket con-

. taining :the ' wastes is placed within the concrete liner prior to =cving the liner into position. m ransport of- -

the liner-is performed"with the operator. stationed be-

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hind a concrete wall at. the waste solidification control panel. A television camera is provided for cperator

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view of operations. involved with solidification.

Liquid wastes requiring solidification come f cm either the evaporator bottoms hold tank or the resin waste hold

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tank. Schematic design of the overall system is shcwn in Figure 1. System parameters are listed in gable 1.

}- Equipment design requires that each waste' form be pro-cessed separately. .Though capable of automatic operation, the-system-is cperated in the manual mode to ; ensure that

, the system is operating properly and that the set points s'

for cement-liquid waste ratics are-as required to achieve solidification. . operator attention is required to actuate the controls for each step of the operation. Metered flow of cement and waste solution are combined at the mixer-feeder which discharges into the concrete liner. Cement feed is maintained at a constant rate for all solidification operations. Liquid waste flows are adjusted as required to provide for a higher liquid waste to cement ratio in the case of beric acid solutions. The normal operating i limit for boric _ acid concentration in wastes to be solidi-fled is a nominal 12*.'. A waste to cement ratio in range of 0.9 to 1.1 is specified for the solidification of boric acid 1

solutions. Other wastes require less cement to achieve

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solidification.

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After the liner has been filled with concrete, it is covered with a lid.and:the' liner'is' moved from the. loading area. The liner is allowed

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to set for five days or more. While the controls exercised in maintaining a proper. cement / liquid ratio ensurefsolidification, an inspection of containers fromLeach: shipment is also perfonned to check for free water.

In the event.that water is. present, cement will be added as required to.

achieve a' water-free mix. The lid is then fastened in. place and sealed

' tolthe liner with a metal seal. The outside of the liner is washed with

.a . series of spray-nozzles to remove any surface contamination .resulting from . loading operations. A smear check.is performed prior to. moving

-the-. liner from the loading area to.the clean side.

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III. OPERATIONS PEPSOP3!ED TO VERIFY SOLIDIFICATION

%. OF RESIN WASTES Testing performed at 3eaver Valley de=cnstrate that

- solidification of resin' with a high resin to water ratio

~ will censistently occur at a waste to cement ratio (W/C) o_' l.25 to 1.75. A high resin to water ratio is obtained F durine. initial processinv .of a full resin waste' hold . tank.

When the resin waste solution is.largelv watert as in the .

case when the resin hold tank leve1' indication decreased to belcw 20 inches, a W/C ratio of 1 to 1.50 is' required to achieve solidification. Results of the test operations are reported in the Appendix to this precedure. ,

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Solidification in this application can be achieved by ,

ad4usting J the feed rate of the liquid waste to produce a W/C ratio in the rance of 1.25 to 1.75 or 1 to 1.5 de-

. pendent on resin hold tank level indication. Ratios cf about 1.6 and 1 are maintained i n actual plant solidifi-cation operations with ficw rate adjustment made at abcut the 20 inch level. This is not meant to imply that there

< is a sudden change in resin to water ratic at this level.

Rather, the change is gradual with the 20 inch indication level serving as a benchmark to indicate that the concen-tration of resin in water is decreasing and a corresponding

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change in the W/C ratic is required. Control of waste flow rate and cement feed to obtain the desired ratic is achieved as follows:

'l-A. FEID RATE CONTECL Three sec.arate feed rates combine to maketo. the resin ,

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concrete mixture :ormec in t.ne mixer-:eecer a:_ the

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solidification system. These are as follows:

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1. Cement Feed Pump W: -

The feed rate of-this pt=p is adjustable over a wide range with gcod reproductibility as shewn in the calibration data presented in the Appendix to this 3

program. Flow is held constant at.a dial setting

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as noted in Chapter 13 of the- Cr.eratine Manual.

With this settingt the n.umn. will deliver the e.rc=.er-amount (lbs) of cement per minute.

2. Resin Waste Ecid Tank Meterinc Pump m

When the level indicator is readinv between pre-s determined levels noted in the~ Operating Manual,

.the dial of the meterinc. e.t==. is set to t.rovide a normal deliver rate of 7 gpm. As the waste tank 4 volume decreases ~, so does the -percent concentration .

of resin in the water. Current experience has.shown that there is little resin left in the tank at a level of about 20 inches and the waste is cc= posed a largely of water. This requires a lower W/C ratio

'l to achieve solidification. At this level (approxi matelv 20 inches), the dial of the meterinc. cumo.

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is adjusted to give a f4ed delivery rate of

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ac. croximatel.v 4 ge. m.

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3. Seal Water Flow to Pump

., This flow is held constant at the minimum ficw re-quirements to protect pump bearings. Flew adjustment is made using a low range flow meter.

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.. . NOTE:' Excessive seal water flow will change the I LW/C and therefore, limits noted in operating-procedure must be followed.

3. OPF3ATOR FOLLOW 4' .

As described above, solidification of' resin wastes is achieved by combining two. fixed flow rate systems with

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one adjustable flow-system (waste =etering =umo).

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liquid waste to cement ratio is maintained within a relatively narrow band in the range where solidifica-tion is known to occur on a consistent basis. With only one control valve to adjust, the operator can 9

=aintain close surveillance of solidification opera-tions. Full time operator attention is maintained since the syste= is operated in the manual =cde. The system

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f holds at the cc=ple, tion of each step until the operator activates a control to continue the sequence of opera-tions.

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C. FINAL INSPECTION As a final check, a visual ~inspecnion is performed to determine the presence of free liquid prior to shipment

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of the full liner. If free water exists, dry -

cement is manually added to achieve solidification of this water.

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IV. OPERATIONS PERFORMED TO VERIFY SOLIDIFICATION OF EVAPORATOR BOTTOM WASTES 3.

b The-liquid wastes generated at Beaver Valley will typi- '

cally contain signifi' cant concentrations of boric acid.

-While boric acid is known to retard the. solidification-

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. of ce nt, the inhib 1:ing_ pro =erties of . boric acid can-be overcome by increasing the concentration of cement in,the mixture and by limiting'the horic acid concentra-tion in the waste solution. Testing performed at Beaver-3-

Valley indicate that the criterion of gcod solidification with no free water can be achieved by maintaining a W/C racio'of 0.9 to 1.1 (by weight) . It is expected that solidificatica will also eccur at icwer N/C ratics, hew-

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ever, this would result is the excessive use of cement.

Gcod solidification will also occur with up to 14-165 horic acid concentrations using this ratio. Results of this work are reported in the Appendi:5 to this procedure.

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Solidification in this application is achieved by using approximate ecuivalent weights of waste and cement in J

s forming the concrete and by limiting the concentration of boric acid in solution to 12% . With a W/C ratio in the

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range of 0.9 to 1.1 and a madi=um boric acid concentration of approximately 12%, all operations are performed belcw 3 the point where free water will form after solidification.

Control of boric acid concentration, waste ficw rate and l l

cement feed to obtain the desired ratio is achieved as

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follows:

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'A. ' BORIC ACID CONCENTRATION

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Waste liquids inL the evaporator are sampled _perio' dical'y during evaporation to determine boric acid concentration and curie content of1the liquid. Hot _ samples 'are pipetted into a volumetric

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flask'and' diluted to prevent precipitation prior to analysis.

Solidification of the wastes is performed.when the following limit 11s attained:

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A nomi.a1 12% boric acid concentration in the liquid.

Some dilution of the boric acid concentration will result from the primary grade' seal water flow added at the mixer-feeder system during

~t he solidification process. This dilution is not considered in calculating boric acid concentration in the end product.

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B. FEED RATE CONTROL Three separate feed rates combine to makeup the evaporator bottoms-concrete mixture formed in the mixer-feeder of the solidification system. These are as follows:

1. Cement Feed pump The feed rate of this pump is adjustable over a wide range with good reproducibility as shown in i

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. the calibration data presented in- the Appendix.

to this program. Flow rate is held constant at a flow rate setting as noted' in Chapter .18 of the Operating Manna'l. With this setting, the pump will deliver the proper amount (pounds) of cement

.per minute.

2. Evaporator Bottoms Eold. Tank Meterine Pum:

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The dial of the metering pump is set to give a-feed delivery rate as identidied in the Operating Manual. A waste-to-cement (W/C) ratic of approxi-

} mately 1 is achieved with this feed rate.

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3. Seal Water Flow to Pump

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- This is held constant at the minimum ficw required

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to o. rotect .numa bearings.

_ Flcw ad";ustment is made using a low-range flow meter.

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NOTE: Excessive seal water ficw will change the W/C ratio; therefore, limits noted in the operating procedure must be fcilcwed.

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) C. OPERATOR FOLLOW As described above, solidification of evapcrator hottom wastes is achieved by combining two fixed flew rate 3

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systems with cne adjustable flew system (waste meter-ing pump). The liquid waste-to-cement ratic is main-tained within a relatively narrcw band in the range

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where solidification is kncwn to cccur en a censistent 10 3

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basis.- With only one control valve to. adjust, the

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operator can maintain close surveillance lof solidifi-cation operations.-- ' Full time operator attention is maintained since the system is operated -in the manual -

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mode. The system holds at the completion of each step until the operator activates a control to continue the sequence of operations.

D. FINAL INSPECT 7.CN

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As a final check, a visual inspection is'perf:::cd to determine the presence of free liquid prior to shipment

9. . of t6e ' full liner. If free water exists, dry cement

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is manually added to achieve-solidification of this water.

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f V.: iDISPOSAL OF SOLID OBJECTS'IN CONCRETE LINERS.

' Solid wastes such:as filter. cartridges and contaminated rags or other radioactive' debris will,- on occasion, be placed within an

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o' pen-mesh metal' basket and immobilized in'the concrete of the waste being solidified. The basket is suspended off the bottom- '

so that the concrete mixture will surround the wastes .in the basket.

Liners that cortain solid objects will be so identified in sur-veillance requirement. reports. .The report will identify the ' type of solids contained (e.g. filters,' rags) and estimate the principle radionuclides .and total curie quantity of the solids.

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VI. CRITICAL ITEMS LIST The following list indicates set points and items in the solidifi-cation system operating procedures (Chapter 18 - Solid Waste Disposal System). Close operator follow is required in these areas to assure preper operation of the systeia and to verify solidification of resin hold tank or evaporator bottom hold tank wastes.

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1. Feed rate of the cement feed pump is held constant at a dial setting as indicated in the operating procedures for all-solidification operations perforned at Beaver Valley. Any variation in this dial setting will affect solidification of the c7ncrete. Since this is an adjustable pump, the dial setting should be checked prior to performing any solidifi-cation operation.

2. When the level indicator of the resin waste hold tank is reading between predetermined levels as indicated in the operating procedures, the dial of the metering pump is set to provide a W/C ratio of 1.25 to 1.75. A low flow rate setting can result in an overly dry mix with perhaps some void areas in the liner. High flow rate settings can result in free water on the top of the liner. It has been established that good results are achieved with the '1/C ratio of about 1.7 (currently in use for solidification); therefore. this ratio should be maintained.

The W/C ratio is determined as follows:

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GPM X 8.6 lbs/ cal of resin slurry l lbs cement / min l l

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i I, a 3.. At a level indication of approximately 20 inches, the dialLof resin waste metering' pump is set to provide a W/C ratio of 1 to

.l.5. Low or high flow rate settings can result .in an overly;

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dry mix or -free water in the liner. Good results. are achieved '

- with 'the W/C ratio of.aobut 1 (currently in use), therefore, this ratio should be maintained.

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'The W/C ratio is' determined as follows:

GPM X 8.3 lbs/ gal of resin slurry lbs cement / minute i

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4. The correct resin-water ratio must be maintained as indicated in the operating procedure. -Insufficient water can result in-the loss of water from the resin beads during the . hydration l process involved as the concrete sets. The hydrated resin can swell on subsequent exposure to water creating tensile forces

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. which can' damage concrete _ integrity. Too much water can result in. free water on the top of the liner.

5. Seal water flow to the metering pumps must be held at a minimum as indicated in the operating procedure. Excessive seal water flow will change the W/C ratio, thus can affect solidification of the concrete.

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6. - ' The dial of.the evaporator bot' toms hold tank metering pump should be-set to_fiveLto give a W/C ratio in the range of-0.9 to 1.1. -

(Existing control procedures result in a W/C ratio of approximately 1). Flow' rate requirements are identified in the operating procedure.

-If flow rates- differ widely from the norm, a good solidification _ may not occur or there can be ' free water on the top of the liner.

7. ' Boric acid determinations are required during evaporation to control

!, 'to a boric: acid concentration in the nominal 10 to 12% range at the

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waste tank. Below 10% there can be free w ' ater in the liner for at..

least the first day after solidification. This water will be absorbed within the concrete. With concentrations above 12%, solidification of lines can occur.

8. Activity determinations are performed when required of evaporator feed and/or bottoms during evaporation so that the activity level of the evaporator bottoms can be estimated. The curie content is estimated /

calculated to minimize radiation level control problems during l processing and shipment of the liner. -

l l 9. In the event that an oil spill occurs, the waste containing oil snall not be processed via evaporation and solidification with concrete.

The Barnwell site license requires that the oil content be less than 1%.

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.VII. LIMITATIONS AND SURVEILLANCE REQUIREMENTS A. LIMITATIONS

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-1.- If; solid wastes (e.g. , filter cartridges, rags, etc.)

are immobilized in the' concrete' matrix, the wastes will be contained within an open mesh metal basket located in the approximate center of.the concrete liner.. The

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basket is suspended off the cottom so that the concrete-mixture will surround the basket.

-2. The concrete in the liner must be solidified and have no free water as determi ied by visual inspection prior to sealing the liner. The liner is inspected far free-

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water prior to sealing which occurs 5 days or more after

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the liner is filled.

B. SURVEILLANCE REQUIREMENTS

1. The Effluent and Waste Disposal Semi-annual Report shall include the following information for each type of solid waste shipped off-site during the report

_ period:

a. . Container volume l

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b.- Total curie quantity (determined by measure-ment cr estimate)

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c. Principal radionuclides (determined by measure-ment or estimate)

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d. Type of waste (e .g. , spent resin, evaporator

• bottoms)

- e. ~ Type of container (e.g., LSA, Type. A, Type 3,

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large quantity), and

f. Solidificatien agent

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-' TABLE 1

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SYSTEM PAFRIETERS PERTINENT TO THE

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PRCCESS CONTROL PROGP.UI Liner capacity Approximately 65 ft3 49 inches diameter x 62 inches

. Liner dimension .

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Liner weight - (fully loaded) Approximately 6000 lbs Shipping container types for 1.5_ inches steel

! liner (if necessary) -1.5 inches lead ecuivalent 4 inches lead equivalent Liquid wastes solidified Spent-resin (bead ferm)

Evaporator bottems which can centain boric acid Solidification material Cement (Specification provided by

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_. +;? ATCOR or'other station approved solidification agent).

Solid wastes immo<ilized Filter, cartridges, rags, etc.

) in liner

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Waste to cement (W/C) ratio 0.9 to 1.1 for evapcrator bottens Typical = 1 s

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W/C ratio for resin wastes 1.25 to 1.75 (high resin content) Typical = 1.7

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W/C ratio for resin wastes 1 to 1.5 (low resin content) Typical = l'

) Maximum boric acid concen- Apprcximately 12%

tration in evaporator bottems hold tank Detection of free water Visual inspection on liner prior to sealing the lid

) Curie centent in liner Determined by analysis of the waste solutien er estimated, based en gamma survey performed after solidificatien Identification of crincicle Estimated by gamma ray spectrum of 2 radionuclides

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waste prior to or after concentration.

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RESIN [ BOTTOMS llOLD 2 -

Il0LD GEMENT

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TANK O __

TANK STORAGE

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SEAL WATER I FLOW

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METERING l PUMP i

METERING r

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- PUMP-

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MIXER FEEDER I

SillPPING LINER l

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FIGURE I BEAVER VALLEY e l UNIT-h SOLIDIFICATION SYSTEM

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APPENDIX A

'l CEMENT SOLIDIFICATION TESTS WITH RESIN AND EVAPOPATOR BOTTOM WASTE SOLUTIONS

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c I. INTRODUCTION-t-

Testing has been performed at Beaver Valley to determine the W/C ratios required to assure solidification of resin and evaporator bottom waste solurions using cement as the 7

immobili::ing agent. The ratios used in this work are based on the cement and liquid feed rates specified in Heaver Valley Operating Procedures. E:dsting W/C ratios were

. - selected as a starting point for this work because gcod r

solidification without free water is new achieved in solid-ification operations performed at Seaver Valley.

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• II. EVAPORATOR 30TTOM SOLIDIFICATION TESTS The evaperator bottem wa'stes generated at 3eaver Valley will typically contain significant concentrations of boric

!; acid. While boric acid is known to retard the solidifica-

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tien of cement, the inhibiting properties;of boric acid can be overccme by increasing the concentration of cenent in the mixture and by limiting the horic acid concentration in the waste solutien. Maximc= boric acid cencentratien in the evaperator bot cms .at Beaver Valley is li=dted to approx-imately 12% because solidificatien in pipe lines can occur above this concentration. Thus 12% concentration was se-

) lected as a ncminal value for solidificatien cperaticas in this process..

Testing wid u simulated boric acid waste solutions was per-

) formed at W/c ratios of 1 and 1.5 with 8, 10, 12, 14 and 16% boric acid solutions. The W/C ratic of 1 was selected as a starting point based on its current use at Beaver Valley. The' ratio of 1.5 was investigated to obtain infor-

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mation concerning permissible range of deviation with respect to waste er cement feed rates. ,A range was used to investi-gate solidification qualities of horic acid solutiens at concentrations cther than 12%. It is unlikely that the 9 boric acid concentration will ever be above 12%, however, the conservative apprcach requires testing in chis range.

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Results of boric-acid-cement solidification tests performed are presented in Table LA. Note that for a W/C ratic of 1, goed solidificacion results were achieved within five days for the entire range of boric acid concentrations tested.

Except for the 8% boric ~ acid test, no free water was

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' observed en any sa=ple at the end of one day. Water in the 8% sa.7ple was gene at the end of twc days. In terms of resistance to penetration with a sharp object, there

• - was little or no difference between the 8, 10 and 12% .

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concentrations at the .end of five days and again at three weeks. Resistance- to penetration could perhaps be described as fair at five days and gced at three weeks. Tae 14 and 16%. concentrations were less resistant to penetration.

.

Test specimens with a W/C ratio of 1.5 shewed sc=ewhat the sa=e results as did the samples with a ratic of 1 with re-spect to the presence of free water. No free water was

' cbserved on any sa=ple at the end of one day, except for the 8% concentration. This water was gene at the end of .

two days. At the end of five days all samples showed much less resistance to penetration than did the sc=ples with

'

a W/C ratic'of 1. Solidification characteristics continued to improve with tine, hcwever, could not be described as goed at any time within the three week test pericd. Re-sistance to penetration can be described as very peer at the end of five days and poor to fair at the end of three weeks. The.re was little if any difference in resistance

,

to penetration damage (at five da; s or three weekr) for any of the horic acid concentrations tested (3, 10, 12, 14 and 16%) with a W/C ratio of 1.5.

As a confirmatory test, two large-scale tests were per-formed to determine if results wculd vary when sample

) volume was increased. Tetal weight of each sa=ple in this case was about 10 lbs . vs 0. 5 lbs . fer the samples pre-viously tested. A W/C ratic 1 was used at boric acid con-centrations of 12 and 14%. After mixing, the samples were

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consideration'in. checking for free water. -As with the.

previous. tests, there was _no indication of free water at theend if one day. . The samples were inverted with nega-tive results to check ' for water. Both samples could be

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.eas ily cenetrated with a pencil point at the end:cf three days, however, were starting to solidify 'at the end of five days. As might he e:gected, these samples behaved as did the small-scale samples.

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3 III. -RESIt{, SOLIDIFICATION TESTS Resin slurries constitute one of the waste forms that are solidified at Beaver valley. In for=ing the slurry, the g resin to water ratio is controlled by draining the waste resin hold tank and then adding water to about 4-5 inches above the resin level. Using this resin-water ratic, solid-ificatien operations are perfer=ed with a W/C ratio of about

1.7. For high water, icw resin slurries, solidificatien operations are performed with a W/C ratio of about 1. Good solidification results are achieved in either case.

_

) Testing with sinulated resin waste solutions was performed at W/C ratics of 1, 1.25, 1.50 and 1.75. A range of resin-water mixtures was investigated in this work. Test condi-tions included the use of mixed bed resin and caticn resin H, to simulate waste forms cs cecur in the plant. Rchs and Haas IRN-150 was uded for the mixed bed resin. This con-sists of a chemically eceivalent mixture of IRN-77 (strong acid) and IRN-78 (s trong base) . IRN-77 was used for the g cation resin. All sa=ples were covered with Saran Nrap after mixing with water and cement to eliminace evaporation frem consideration in checkingf'or free water.

v Results of the resin solidification tests are presented in

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Table JA. There was no indication of free water at the end of the first day in every test that simulated the ratics used in plant solidificatica aperatiens. One test that

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O was outside this range (No. 1) shewed sc=e indication of free water for two days, however, was dry on 9.e third day.

All concretc samples except for No. 1 were hard by the fourth day. Test No. I was fairly resistant to penetration with a s

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'. sharp object on the fourth day. Results of the resin solidification tests described here can be su=:tarized by sta':ing that all samples tested (including No. 1) =et the required end conditions for shipment off-site.

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IV. CEMENT FEED CALIBRATION Cement feed rate during solidification operations at Beaver Valley is held as a constant with a dial setting of 5.

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The vender literature does not include data'cencerning reproducibility of the cement feeder so a calibration test was performed to obtain this information. The data is as follows:

.

Dial Settine Cement Yeed Rate for Three Runs ( Eb s/ min. )

.

4 28 28 28.4

' 5 34.5 34.5 34.5 45 43 45.3

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The variation obtained in these runs will have no signifi-

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• cant effect on W/C ratios obtained during solidication operations. In fact, a considerable-wider latitude could be tolerated without problem.

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