Tetra Tech, Inc.

10306 Eaton Place, Suite 340 Fairfax, VA 22030 phone 703 - 385 - 6000 fax 703 - 385 - 6007 DATE: July

3 , 2008 TO : Paul Shriner and Jan Matuszko FROM : Christine Wong, Kelly Meadows and Shari Goodwin, Tetra Tech SUBJECT: Design Intake Flow for Test Cooling Water Intake Structures Introduction After review ing technology efficacy studies impingement mortality

data , EPA and Tt identified e fficacy of Ristroph
- ty

pe coarse mesh traveling screens. technology
- based limits , EPA requested that Tt determine the intake flows that correspond to the study p eriods cl ear in describing the test conditions, including the intake flows withdrawn during testing. As such, Tt was tasked reviewed the studies and other supporting documentation (including summary reports, prim ary studies, and information from flow (DIF) of the cooling water intake structures (CWI S) reviews are presented in the table on the following page. Degree of Confidence Tt is reasonabl y confident that the DIFs for the Dunkirk and Huntley because the design capacity is explicitly

stated for the study

screens at each facility
. (Whether the screens operated at assuming they

were.) Based on the information available, Tt used its best professional judgment to assign a CWI S
- specific DI F to the Arthur Kill and Salem studies. representatives at both facilities communication efforts have not been successful with either facility. If and when contact is made with the facility representatives and DIF assumptions are confirmed, T amend the table as necessary . 

### MEMORANDUM 10306 Eaton Place, Suite 340

and Jan Matuszko , EPA Christine Wong, Kelly

Meadows and Shari Goodwin, Tetra Tech Design Intake Flow for Test Cooling Water Intake Structures technology

efficacy studies in the June 23 , 2008 memo from Battelle , EPA and Tt identified 6 studies that best represent ty pe coarse mesh traveling screens. To enable the development of , EPA requested that Tt determine the intake flows that correspond to the study p eriods in these documents . None of the studies were completely ear in describing the test conditions, including the intake flows withdrawn during testing. As such, Tt was tasked with determining an estimate of the flow rates. reviewed the studies and other supporting documentation (including summary reports, ary studies, and information from industry survey s) to determine the design intake flow (DIF) of the cooling water intake structures (CWI S) tested
. The results of Tt’s study reviews are presented in the table on the following page. Tt is reasonabl y confident that the DIFs for the Dunkirk and Huntley studies are correct

capacity is explicitly

stated for the study

screens at each facility
. (Whether the screens operated at the DIF for the entir e study period is unkn own; Tt is Based on the information available, Tt used its best professional judgment to assign a

DI F to the Arthur Kill and Salem studies. T t has attempted to contact both facilities to confirm the se assumptions. At this time, communication efforts have not been successful with either facility. If and when contact is made with the facility representatives and DIF assumptions are confirmed, T

. Christine Wong, Kelly

Meadows and Shari Goodwin, Tetra Tech

, 2008 memo from Battelle for best represent the To enable the development of , EPA requested that Tt determine the intake flows that . None of the studies were completely ear in describing the test conditions, including the intake flows withdrawn during the flow rates. T t reviewed the studies and other supporting documentation (including summary reports, survey s) to determine the design intake

The results of Tt’s study
studies are correct , capacity is explicitly

stated for the study

screens at each facility
.

own; Tt is Based on the information available, Tt used its best professional judgment to assign a has attempted to contact communication efforts have not been successful with either facility. If and when contact is made with the facility representatives and DIF assumptions are confirmed, T t willFa cility Name Generating

Units/CWISs DIF for Test

CWIS Screens Notes Data Source(s) Arthur Kill Unit 20 87 MGD Each unit contains 4 screens; only one of the four screens was upgraded for the study. No information provided on unit operation during study ; assume th at the flow through the upgraded test screen was 0.25 the maximum flow for the unit (347.9 MGD

– provided in study), or 87 MGD. EPRI2007

Unit 30 85 MGD Each unit contains 4 screens; only one of the four screens was upgraded for each study . No information provided on unit operation during study ; assume that the flow through the upgraded test screen was 0.25 the maximum flow for the unit (339.3 MGD

– provi ded in study), or 85 MGD. EPRI2007

Dunkirk Screenhouse

#1 , including Units 1 and 2 92.2 MGD Modifications were made to one of three existing screens. No information provided on unit operation during study ; assume flow through the test screen at maximum capacity . 92.2 MGD specified as prototy pe study screen capacity
. Beak Consultants, Inc., 2000 (DCN 5
- 4327) Huntley Units 67 and

68 82.8 MGD All (4 existing) screens replaced at Units 67 and 68 with 5 Ristroph
- ty pes screens. No information provided on unit operation during study ; assume flow through the test screen at maximum capacity . 82.8 MGD specified as prototy pe study screen capacity
. Be ak Consultants, Inc., 2000 (DCN 5
- 4325) Salem Unit 1

(1995 study) 266.4 MGD No information provided on unit operation during study ; assume flow through the test screen at maximum capacity . 266.4 MGD specified as Unit 1 design flow rate; 1995 study looked onl y at performance of Unit 1 screens. Ronafalv y, Cheesman, and Matejek, 20 00 (DCN 5
- 4333) Units 1 and 2 (1997
- 1998 study) 532.8 MGD No information provided on unit operation during study ; assume flow through the test screen at maximum capacity . 266.4 MGD specified as flow rate at each unit; 1997
- 1998 study looked at performan ce of screens at both Unit 1 and Unit 2 for a total DIF of 532.8 MGD. Ronafal vy , Cheesman, and Matejek, 2000 (DCN 5
- 4333)