ML070400141

E-Mail from G. Hinrichs of Entergy to J. White of USNRC and T. Rice of Department of Environmental Conservation, Regarding GZA Procedure

ML070400141
Person / Time
Site:	Indian Point
Issue date:	10/19/2006
From:	Hinrichs G Entergy Corp
To:	Rice T, Jason White NRC/RGN-I/DRS/PSB2, State of NY, Dept of Environmental Conservation
References
FOIA/PA-2007-0080
Download: ML070400141 (10)

Text

1,ý'Jonn Wrirle - ý-VV: UZA PHUUEUUFiE Paale 111 I4onn Wnite - I-W: ULA PHUULUUHI=

Paqe 1 Ii From:

"Hi/ichs, Gary H" <ghinric@entergy.com>

To:

<jrwl @nrc.gov>, "Timothy Rice" <tbrice@ gw.dec.state.ny.us>

Date:

10/19/2006 5:24:45 PM

Subject:

FW: GZA PROCEDURE John and Tim Here is the GZA procedure we are. using for the Pilot test. Entergy has accepted the procedure, performed a 50.59 review and initiated a Work Order to perform the test. The schedule is to perform the step test on Friday 10/20, and the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> continuous flow test on Tues 10/24 through 10/26, weather permitting.

<<GZA SOP REMEDIATION WELL RW-1 PILOT TEST - PROCEDURE.pdf>>

CC:

"Adler, Joseph J." <jadler@entergy.com>

I John White - TEXT.htm Paae 1 John and Tim Here is the GZA procedure we are using for the Pilot test. Entergy has accepted the procedure, performed a 50.59 review and initiated a Work Order to perform the test.

The schedule is to perform the step test on Friday 10/20, and the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> continuous flow test on Tues 10/24 through 10/26, weather permitting.

<<GZA SOP REMEDIATION WELL RW-1 PILOT TEST - PROCEDURE.pdf>>

John White - GZA SOP REMEDIATION WELL RW-1 PILOT TEST - PROCEDURE.pdf Page 1 STANDARD OPERATING PROCEDURE PUMPING TEST INDIAN POINT ENERGY CENTER October 11, 2006 1.0 SCOPE AND APPLICATION Pumping tests are frequently used to assess aquifer properties. They can be particularly useful when evaluating groundwater flow in space and time and the effects of boundary conditions imposed on a hydrogeologic regime.

Typically, pumping tests are used to obtain aquifer characteristics such as hydraulic conductivity (K), transmissivity (T), specific yield (Sy) for unconfined aquifers, and the storage coefficient (S) for confined aquifers. This standard operating procedure (SOP) has been prepared to outline the protocol for conducting a pumping test in extraction well RW-1 at the Indian Point Energy Center (IPEC) in Buchanan, NY.

Information generated by the subject test will provide a portion of the data required to design a groundwater extraction system for containment of the contamination proximate to the Unit 2 Spent Fuel Pool (IP2-SFP). If test results are as anticipated, well RW-1 will be included as a component of that system. Based on testing completed to date, we believe the bedrock aquifer will effectively respond to pumping as an unconfined, porous media, with significant heterogeneities, and a small storage coefficient.

Again based on testing to date, we anticipate that an extraction rate of 4 gallons.per minute (gpm) will produce the desired capture zone.

The Hydrodynamic Containment System, for which this pilot test is being conducted, will have two design objectives: 1) Preventing tritium contaminated groundwater from migrating away from the Unit 2

- Spent Fuel Building; and, 2) Minimizing the potential for strontium impacted groundwater to migrate from the Unit I area to Unit 2.

Keeping these objectives in mind, there are two basic alternative pumping strategies: 1) Constant Rate Extraction; and 2) Constant head (at the extraction well) extraction.

There are advantages and disadvantages to either alternative. For example, in a uniform flow field that experiences relatively small seasonal water table fluctuations, a constant head system has the potential to pump only the water required to maintain containment.

A potential disadvantage is managing the higher flows that occur during precipitation events.

The constant rate system takes advantage of aquifer storage to moderate variations in extraction rates, but generally does so by pumping more water (in the long run) than is required. While, traditionally, this has been the preferred alternative, the potential for inducing migration from the vicinity of Unit 1 may limit the viability of this containment strategy.

We will use the data generated from the pumping test to examine the merits, disadvantages, and risk of each system. Regardless, of the final system selected, we will use the start-up period (of either system) to confirm our design assumptions and evaluate the effectiveness of our controls.

2.0 METHOD

SUMMARY

Overall, the test will consist of a pre-test monitoring period, a step drawdown test, a single rate pumping test, and a recovery test. For one week prior to commencement of the step drawdown test, water levels in the extraction well and nearby monitoring wells will be recorded. The flow rates from the Unit I north Page 1 of 8

LJohn White - GZA SOP REMEDIATION WELL RW-1 PILOT TEST - PROCEDURE.pdf Page 2 1 STANDARD OPERATING PROCEDURE PUMPING TEST INDIAN POINT ENERGY CENTER October 11, 2006 curtain drain and chemical systems subbasement drain, and the Unit 2 footing drain will also be monitored. Finally, precipitation events will also be monitored during this period. It is anticipated that the ongoing monitoring well installations will be far enough away from RW-1 that the drilling will not impact the pilot extraction test. However, a log of drilling activities will be kept to evaluate interferences should they arise.

The step drawdown test will consist of pumping initially at a low rate for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. The pumping rate will be incrementally stepped up at one hour intervals until the pumping rate has reached 5 gpm. The aquifer will be allowed to recover and a single rate pumping test will be conducted for three days. This will be followed by a period of no pumping and observation of the aquifer recovery.

3.0 INTERFERENCES AND POTENTIAL PROBLEMS Interferences and potential problems include the barometric pressure changes (if not auto-corrected by the transducers or manually corrected based on a transducer dedicated to barometric pressure recording),

precipitation, groundwater withdrawals or injections (e.g. nearby construction activities such as dewatering or concrete cutting, drilling work, monitoring well sampling and tidal fluctuations). If any of these potential interferences exist, they should be described in the field notes.

4.0 EQUIPMENT/APPARATUS The following equipment will be needed to conduct the step drawdown test:

Variable speed submersible pump Power supply Water pressure transducers Flow meters Dataloggers Electronic water level indicators In-line Filtration equipment Watch or stopwatchs Five gallon (or larger) container Semi-log graph paper (if dataloggers cannot display static water level)

Calculators Flashlights

(

pH/conductivity/dissolved oxygen/redox potential meters Waterproof ink pen and log books Sample Bottles Manuals and Field Forms Page 2 of 8

J nWh*te - GZA SUP HEMEDIATION WELL RW-1 PILOT TEST - PROCEDURE.Ppd.

Pa.. 3 STANDARD OPERATING PROCEDURE PUMPING TEST INDIAN POINT ENERGY CENTER October 11, 2006 5.0 PROCEDURES The following subsections will describe the procedures necessary to perform the pumping test. All data will be collected by integrated, electronic datalogging equipment or the field forms for hand measurements that are attached as to this SOP.

5.1 Preparation

1)

Review appropriate provisions of Health and Safety Plan

2)

Check that that the extraction well has been properly developed and that any FLUTE system or other apparatus have been removed from the corehole

3)

Decontaminate any equipment that is purchased or rented for this test.

4)

Install the pump in the extraction well and connect to power, controllers, instrumentation and discharge piping. Check that activation of the pump does not cause electrical interference with the transducers.

5)

Check that all Site transducers and dataloggers are working properly and are fully charged.

Have additional transducers/dataloggers available in case of malfunction.

Check that the clocks on all transducers are synchronized to NIST time. Check that personal watches or stopwatches are synchronized with the dataloggers to NIST time.

6)

Check that pump is in working order and that the flow control system allows a constant flow to be established quickly and easily. This check needs to be performed at least 2 days prior to the step test. Also check that all piping is in place, not leaking, and connected to the flow meter, the water quality parameter probe, and, ultimately, to north curtain drain.

7)

Check that the flow meters are accurately measuring flow.

8)

Perform a site survey and visit each monitoring well. Check that each monitoring well is in good condition, well caps are not missing, and that well keys are available.

5.2 Pre-test Monitoring

1)

Check that the pump has been installed into extraction well RW-l according to manufacturers instructions. Typically the pump can be installed 5 feet from the bottom of the core hole. Install a pressure transducer approximately 2 feet above the top of the pump and attach to datalogger.

2)

Install pressure transducers and associated dataloggers in each of the primary monitoring wells to be evaluated (i.e. MW-30, MW-31, MW-32, MW-33, MW-34, MW-35, MW-111, MW-36, MW-37, MW-42, MW-47, MW-51, MW-52, MW-53 and 1-2). In cases where the transducers are already installed, check transducer function including temperature, zero and span response. Please note that the listed monitoring wells are the most important and those for which special time intervals will be recorded during Page 3 of 8

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-HUU~lJUHE.pdt ae 4 A STANDARD OPERATING PROCEDURE PUMPING TEST INDIAN POINT ENERGY CENTER October 11, 2006 portions of the pumping test. This is important to evaluate if the step drawdown test has an unanticipated effect(s). In the rest of the SOP, these wells will be referred to as "the primary observation wells." The static water levels in the remaining monitoring wells are to be monitored at thecurrent frequency of once per hour. Monitor static water levels in the primary observation wells and extraction well for a period of one week at a frequency of once per hour. Note any potential interference. It should be noted that if a monitoring location has more than one depth interval, each interval should be outfitted with a pressure transducer and the static water level monitored as appropriate.

3)

Monitor the flow at the Unit 1 north curtain drain and chemical systems sub-basement and Unit 2 VC footing drain. The Unit I north curtain drain flow will be measured via "continuous" transducer monitoring of the water elevation in the spray annulus sump along with the Unit 1 treatment system flow totalizer.

The Unit 1 chemical systems sub-basement sump drain flow will also be similarly monitored using a water elevation transducer and the existing flow totalizer. The Unit 2 VC footing drain discharge into manhole 5 will be monitored with a calibrated container and a stopwatch. Unit 1 "drain transducers" should be downloaded every two to three days and the totalizers read once a day. The Unit 2 drain should be monitored once a day during the pre-test period, with increased frequency during/after precipitation events.

4)

Download transducers/dataloggers onto a laptop and check that the transducers and dataloggers are operating properly and there is sufficient remaining memory available in the datalogger every two to three days during pre-test period. Download the laptop into backed-up network files directly after downloading transducers/dataloggers.

5.3 Step Drawdown Test

1)

At the beginning of the test (i.e. time = 0 hrs), the pump should be turned on and set to quickly and consistently begin discharging at I gpm. Simultaneously, the dataloggers attached to transducers in the primary evaluation monitoring wells and extraciion well should begin recording in logarithmic mode with the maximum time interval set to 5 minutes. Generally, the reading interval for the pumping well should not exceed the following guidelines:

Elapsed Time Since Start of Test Interval Between Measurements (Minutes)

(Minutes) 0-10 0.1i.e,, 10_seconds) 10-15 1

15-60 5

It is anticipated that the actual measurement interval for the RW-I test will be logarithmic up to a maximum time between measurements of 5 minutes.

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Flow totalizers at the Unit I north curtain drain and chemical systems sub-basement drain should be read just prior to the start of the test and then every four hours thereafter with the respective elevation transducers downloaded daily. The Unit 2 VC footing drain flow should be recorded just prior to the start of the test, two hours after test start and then every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> thereafter until the test is complete. The date, time, visual observations, and recorded flow rate (where applicable) are to be recorded in the log book.

3)

Manual readings from the extraction well flow meters should be recorded in the log book once every 15 minutes (max) and the respective dataloggers downloaded and transferred to the data base once per day. It is important to keep the flow rate at +/-10% of the intended flow.rate.

4)

Standard field sampling water quality measurements from the recovery well should be recorded at the beginning and end of the step-drawdown testing, as well as whenever radiological test samples are obtained.

If the water quality meter is equipped with a datalogger, it should be synchronized with the pressure transducer dataloggers and information should be logged as stated in step 1. Radiological samples should be obtained after two well volumes have been extracted and just prior to the end of the test

5)

Steps 1-4 should be repeated changing only the pumping rates (i.e. 2, 3, 4, and 5 gpm).

Each step of the step drawdown test should last 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. If the desired flow rates cannot be maintained without inducing unacceptable drawdowns it may be desirable to terminate the test without completing all five steps.

For the purposes of this pump test, unacceptable drawdowns are defined in terms of their effect on average linear groundwater velocity as described in Section 6.0.

6)

Following 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> of pumping at 5 gpm, the data should be preliminarily analyzed to assess if the required information has been obtained or if higher pumping rates are required..

Assuming sufficient data has been obtained, the pump should be shut off.

Simultaneously, the dataloggers should begin recording as described in step I above.

Once the water levels in the extraction well and primary observation wells have stabilized, the step drawdown portion of the pumping test is complete. Ideally, the step drawdown test would be conducted on a Thursday or Friday and the aquifer allowed to recover over a weekend. Prior to commencement of the following constant rate pump test, the aquifer recovery data must be reviewed to evaluate whether or not the aquifer has rebounded to pre-pumping levels. Based on this evaluation, the constant rate pump test commencement may be delayed.

7)

Transducers/dataloggers should be monitored frequently to verify that they are working properly and retain sufficient remaining memory. Download data as necessary and at least daily during the step drawdown test.

Download the laptop into the backed-up network files each day.

8)

Hoses and connections shall be inspected every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for leaks.

Page 5 of 8

tIJohn White - GZA SOP REMEDIATION WELL RW-1 PILOT TEST - PROCEDURE.pdf Paae 6 11 STANDARD OPERATING PROCEDURE PUMPING TEST INDIAN POINT ENERGY CENTER October 11, 2006 rant Rate Pumping test the beginning of the constant rate pumping test (i.e. time = 0 hrs), the pump should be turned on and set to quickly and consistently begin discharging at 5 gpm. [Note: the test may not be conducted at 5 gpm. This flow rate is the current estimate of the rate to be used but must be verified (or modified) based on results of the step drawdown test. If for example, 3 gpm is the maximum sustainable pumping rate in RW-1, then that shall be the pumping rate used for the constant rate pumping test.] Simultaneously, the dataloggers attached to transducers in the primary evaluation monitoring wells and extraction well should begin recording in logarithmic mode with the maximum time interval set to I hour. Generally, the reading interval for the pumping and observation wells should not exceed the following guidelines:

It is anticipated that the actual measurement interval for the RW-1 test will be logarithmic up to a maximum time between measurements of 15 minutes.

I)

Flow totalizers at the Unit I north curtain drain and chemical systems sub-basement drain should be read just prior to the start of the test and then every four hours thereafter with the respective elevation transducers downloaded daily. The Unit 2 VC footing drain flow should be recorded just prior to the start of the test, two hours after test start and then every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> thereafter until the test is complete. The date, time, visual observations,

lýJohn White - GZA SOP REMEDIATION WELL RW-1 PILOT TEST - PROCEDURE.pdf Pag7JI STANDARD OPERATING PROCEDURE PUMPING TEST ZINDIAN POINT ENERGY CENTER October 11, 2006 the datalogger on a daily basis. Download the laptop into the backed-up network files each day.

5)

Following at least 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> of pumping at the selected extraction rate (assuming water levels have stabilized in the primary observation wells); the pump should be shut off.

Simultaneously, the dataloggers should begin recording as described in step 1 above.

Once the water levels in the extraction well and primary observation wells have stabilized, the test is complete. Ideally, the constant rate pumping test would begin on a Monday and end on a Wednesday. The recovery portion of the constant rate aquifer test would then begin on a Wednesday and possibly end on a Friday (assuming the aquifer has sufficiently recovered).

6)

Hoses/connections shall be inspected every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> for leaks..

5.5 Post Operation

1)

Return logging frequency of data loggers to hourly

2)

Review log book and field notes for completeness.

3)

Decontaminate all equipment that will not remain installed at the site.

6.0 STRONTIUM MIGRATION/TEST SHUTDOWN CRITERIA Strontium-90 has been found in groundwater near Unit 1. It is important that the groundwater withdrawal from RW-I does not cause impacted groundwater from Unit I to migrate to Unit 2. Therefore, once a day it will be necessary to calculate the average linear velocity of groundwater in the vicinity of Unit I moving from Unit 1 toward Unit 2. The equation for average linear velocity is shown below:

V=K*i*FS / n, Where:

V = average linear'groundwater velocity K = hydraulic conductivity = 0.3 ft/day (from bedrock packer and specific capacity data) n, = effective porosity = 0.02 (assumed) i = gradient (to be calculated)

FS= Factor of safety = 1.5 (assumed)

The gradient must be derived from groundwater contour plots that will be generated daily. The gradient can be measured as the change in groundwater elevation perpendicular to equipotential lines and moving from Unit I to Unit 2. Use the gradient and information supplied above to calculate the average linear velocity proximate to Unit 1. If this average linear velocity shows that groundwater from Unit 1 will reach Unit 2 in less than or equal to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, the constant rate pumping test should be stopped or pumping rates decreased appropriately. Likewise this procedure should be conducted twice (after 2 gpm and 5 gpm pumping rates) during the step drawdown test. However, in this instance, the criteria for Page 7 of 8

I.John Whie -GZASOPREMEDIATION WELL RW-1 PILOT TEST - PROCEDURE.pdf Pace 8 11 z'I&

STANDARD OPERATING PROCEDURE PUMPING TEST INDIAN POINT ENERGY CENTER October 11, 2006 pumping test termination shall be if the groundwater average linear velocity suggests water from Unit 1 will reach Unit 2 within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. It should be noted that the gradient should not be calculated using the static water level in the pumping well.

Other reasons that either pump test should be terminated include the following:

0 Emergency (e.g. fire doors closed, unacceptable radiation levels in any working area, etc.)

At the request of appropriate Entergy personnel Activation of station sirens.

Significant leakage of pump discharge line Evidence of pump maifunction (e.g. unsteady pumping rate, electrically shorting equipment, etc.)

Water leveldrops below the pump intake in the extraction well Precipitation causes significant differential changes to potentiometric surface. This would likely occur if, for example, one inch of rain fell during the course of one day.

7.0 QUALITY ASSURANCE/QUALITY CONTROL Instruments and equipment used during the pumping test should be calibrated according to the manufacturer's instructions. Documentation of calibration should be filed with the test data records. The calibration records will consist of laboratory measurements and any on-Site zero or calibration. Where possible, on-site flow measurements should be checked using a container with measured volume and a stopwatch.

8.0 REFERENCES

This SOP was adapted from the United States Environmental Protection Agency SOP # 2045, dated 10/04/1994, and entitled "Controlled Pumping Test".

This document is available on-line at http://www.dem.ri.gov/pubs/sops/wmsr2045.pdf.

9.0 ACCEPTANCE This SOP has been developed in accordance with accepted practices in the field. These procedures have been revie.d and approved by GZA.

David Winslow, PhD, P.G.

Matthew J. Barvenik, LSP Senior Project Manager Principle-In-Charge

• /eMantor P

IVý Senior Project Manager Page 8 of 8