### SCREENWASH 

### RETURN WATER MODIFICATION STUDY 

### GLENWOOD 

### AND 

### PORTJEFFERSON POWER STATIONS 

### KEYSPAN CORPORATION April 1,2002

BY KeySpan Environmental Engineering and Compliance Department



### 175East Old Country Road Hicksville, 

### NY 1 

### 1801

Iwater empties onto the beach along side the screenhouse foundation. The trash basket is emptied from time to time to dispose of accumulateddebris. The objective ofthe proposed conceptual fish return scheme, as depicted on drawing PJPSM-FY-99000(attached) is to safely return any sea life caught in the intake screen wash system back to Port Jefferson Harbor. This would be accomplishedby removing the trash basket from the intake sump area located on the north side ofthe intake and replacing it with a stainless steel open trough. The trough would route the discharge from the screen wash trench, across the sump, to a 24''dia. fiberglasspipe supported on the outside of the sump structure. The pipe, running in an easterly direction,would deliver the discharge and any included sea life to a point at least 14feet beyond low tide, thereby insuring safe return to sufficientwater depths. The pipe is on an approximate 1YO slope and is equipped with two y-sections for clean out in the event the pipe becomes clogged. The total length of the return pipe will be approximately 120feet. It will be supported by brackets mounted on the existing sheet steel bulkhead at an elevation of approximately +8.5'(MLW). Upon approval of the conceptual fish return scheme and receipt of any required wetlands permits, final construction drawingswill be prepared. Depending on availability of KeySpan construction forces, materialprocurementand contractor selectionwould then be initiated,with constructionto be completed approximatelytwo months after start of work.

AC Gross 4- 1-02

3112

/----- ELEVATION “D

### - D’

Figure N-13 Intake StrUCtUre,Units 4&5 Glenwood Power StationKeyspan Corporation Environmental EngineeringDepadment 175EasiOId Countrv Road Hicksville,New York.11801-4280
June 21 , 2002 Mr. Larry Wilson NYSDEC Bureau of Habitat 625 Broadway,5' Floor Albmy, NY 12233-4756 Re: Intake Mitigation Projects at Keyspan Power Stations Submission of Study of TravellingScreen Continuous Operation Dear Mr. Wilson: Pursuant to Item 2 of our letter of March 29, in which we agreed to conduct and provide certain studiesrequested in your letter ofFebruary 12,2002, please find enclosed our report onthe feasibility of increased screen wash frequency at the Port Jefferson, Glenwood and Far Rockawaypower stations. Northport and EF Barrett presently operate their screens in a continuousmode. Thereport concludesthat, while more frequent screen operation is feasible, wear and tear, maintenance, electrical consumption and maintenance are all increased. In addition, a number of equipment upgrades would be required to supportmore frequent operation. Added costs for continuous operation would be $1 10, 577the first year and $79,777 per year thereafter. In order to achieve maximum effectiveness in reducing fish impingement exposuretimes while minimizing equipment wear and operational costs, we examined the fish impingementdata collected during the extensivemonitoring programs conducted in 1976-77. These data are summarizedby month for each plant in the attached table. This indicatesthat amajority of impingement at the three plants occurs during relatively few months. Based on these data, we propose to operate the screenswash systems continuously during the months of October, November and December at Glenwood and Port Jefferson and during May and November at Far Rockaway. If you have any questions on the above, please call me at 5 16-545-2561. Very truly yours,

A. Christopher Gross EnclosuresMONTHLY FISH IMPINGEMENTTOTALS, 1976-77DATA

JANUARY FEBRUARY MARCH APRIL MAY JUNE JULY AUGUST SEPTEMBER OCTOBER NOVEMBER DECEMBER

TOTAL FAR ROCK GLENWOOD PORT JEFF BARRETT NORTHPORT (1 UNIT) (2UNITS) (2UNITS) (2UNITS) (3UNITS)

1976 1976 1976 1976 1976-77ave 448 240 624 9139 5342 242 864 756 1379 2785 240 344 168 4996 1685 1528 452 413 24215 1087 2484 320 856 8062 1763 1216 546 315 2751 1198 1390 720 712 2891 677 1804 148 632 2749 2786

0 259 880 1649 1814 1472 1346 3000 28001 1100 2064 15880 10808 63496 2969 1040 3192 7392 7348 4805

13928 2431 1 26556 156676 28011

Note: Barrett and Northportscreensoperatecontinuously at present FR, GWand PJ proposed to operatecontinuously in months bolded ACG 6/20/02June 

### 20,2002

Continuous Traveling Screen Operation Feasibility Study Far Rockaway, Glenwood, Barrett, Northport and Port Jefferson Power Stations

Purpose: This study was conducted, at the request 

### ofNew York StateDepartment 

### of Environmental Conservation, to evaluate the feasibility ofrunningthe

’ Traveling Water Screensin a continuous mode rather than intermittent operation. 

### DEC is concerned that any fish impinged on the screensmay be adversely affected by extended exposure during periods when the screens are not operating. To conduct this study, equipment upgrades were investigated, additional maintenance and power costs were calculated and reliability issues were looked at. The report attempted to answer the questions; can we operate the Traveling Screens continuously, if so, what upgrades would be necessary and then, what would the additional costs be? Executive Summary: Continuous operation ofTraveling Screens decreases the time to failure of the wear components and increases the electrical power consumption. Although the drive motors for the screensvary between 3/4 

### hp and 3 hp, the larger power usage 

### comes fi-omthe screen wash 

### pump motors that 

### vary between 40 to 50 hp, by design. 

### If screens for all Keyspan’s Long Island stations were run continuously instead 

### ofthe present operation, the additional auxiliary power costs would be $39,399/year.
The report details equipment upgrades available for continuous operation. A major portion of the upgrades was conducted a few years ago. All our power stations now have fiberglass baskets with stainless steel screening material. This reduces the weight 

### ofthe baskets by 40%, resulting 

### in less power consumptionand less loading on the headshaft bearing. The original

1specification for headshaft and footshaftbearing material was bronze. Bearing material upgrades are now available and are recommended in this report to provide increased wear protection. 

### Most of ourplants still have bronze bearings. The differential material cost for the improved bearing material is $1400/screen or $30,800 for all 22 screensfor the Long Island plants. Bearing replacements could be made duringnormal maintenance periods, when the bronze bearings would have been replaced 

### fi-omnormal wear. Increased maintenance would include additional time to clean screen wash nozzles, to clean screenwash pump strainers and time for increased lubrication frequencies. Additionally, increased attention will need to be given to assure screen alignments are true. Misalignments can cause accelerated wear. This report estimatesthe cost for additional preventative maintenance labor would be $40,378/year, if all screens were operated continuously, as opposedto the present operation. During the plant equipment inspections and discussions with plant personnel, it was determined that continuousoperation for extended periods was a feasible operation for all our plants. Northport Power Station and the Barrett Power Station already run their screensmostly in the continuous mode. These two stationshave 12 screens out of the system’s 

### 22 screens, therefore we already run more than half ofLong Island’s Traveling Screens mostly in the continuousmode. SinceNorthport and Barrett already run their screens mostly in the continuous mode, a decision to operate all screenscontinuously would directly affect Far Rockaway, Glenwood and Port Jefferson. The increased differential costs for auxiliary power, upgraded bearing material and increased labor costs would initially cost 

### $1l0,577/year. This number includes the improved bearing upgrades for all our plants. Recommended modifications can be made duringthe routine maintenance outages and would not preclude continuous operation, duringpeak impingementperiods, at this time. 

### A review ofthe 1976-77 fish impingement data at the plants indicates a peak in impingement abundance at Gfenwood and 

### Port Jefferson during

2November, with elevated numbers also during October and December. Far Rockaway numbers peak duringthe months ofNovember and May. Therefore, maximum benefits, in terms 

### ofreduction of impingement exposure, would be obtained ifthe Traveling Screens were 

### runin the continuousmode duringthese specific months. Northport and 

### EF Barrett already operate their screensmostly in the continuous mode, so exposure times there are presently minimized. Study Methods: Equipmentupgrade recommendations were discussed with the Traveling Screen manufacturers. Contactswere made with other utilitiesthat operate their screens continuously. They were questioned on what equipment changeswere performed and what problems were encountered. The original specificationsfor our Traveling Screenswere looked at. Equipment inspections and personnel interviews were conducted at all our power stations. Plant personnel discussed their present maintenance concerns and their operational methods. Finally, vendor manuals were referred to in orderto compare manufacturer’s recommended maintenance intervals 

### to those performed in the field. Manufacturers Recommendations: Equipment upgrades recommended by the manufacturers include stoody bearings for the footshaft and Thordon bearings for the headshaft. KeySpan has already converted all our baskets to fiberglass baskets with stainless steel screens. Vendor Manual Recommendations: Normally screens should be operated when 6” differential exists. With up to a maximum differential 

### of 30”, the screenscan still start with a solid shearpin. If the screens are operated continuously, they shouldbe run at the slowest speed possible to maintain a 

### 6” differential. With 

### 100%clean screensthere will be a 0.I3-foot head loss across the screens, however with 70% clean screensthere will be a 0.30-foot head loss.

3Electrical Power Consumption: Assumed a fuel cost 

### of $3.50/rnillion BTU resulting in an auxiliary power cost of $O.O3248/k~-hr: Total: 22 screens continuousoperation =$4,461 .%/year Total: 1 

### 1 screenwash 

### pumps continuousoperation = $101,945.39/year
The total auxiliary power costs for the present operation, where Northport and Barrett run mostly in the continuous mode and the remaining plants 

### run 12.5% 

### ofthe time is $67,008. The added auxiliary power costs to run all the plants continuously is therefore $39,399.
ConclusionsRecommendations: The disadvantages

### of operating the traveling screens continuously include increased wear on the bearings and chains. This increased wear requires more frequent greasing and inspections. 

### To counter some 

### ofthe wear on the bronze bearings, upgraded materials 

### of construction should be used, specificallyThordon material for the upper, headshaft bearing and Stoody material for the lower, footshaftbearing. Theseupgrades can be done during normal maintenance outages, sincethe bronze bushings on the screensnow are acceptable for the interim. The improved materials will provide for longer intervals before replacement. For all the screens

### on the Long Island plants, total material upgrade costs would be 

### $30,800 or $1,40O/screen. The carrier chain and drive chain will need to be inspected and adjusted more frequently. With proper inspections, lubrication and adjustments, the screens can be maintained atthe same level ofreliability. Continuous operation will increase the auxiliary power consumption, mainly due to the screen wash pumps. The additional auxiliary power costs are estimated at $39,399,if all the screens are run continuously, over the present operation.

4Continuous operation will increase the labor required to cleanthe spray nozzles more often, clean the screen wash strainersmore often, increase the lubrication schedules, and increase the time to make screen inspections and alignments. The time required for the IOscreens at Far Rockaway, Glenwood and Port Jefferson were estimated at an additional one-man day per month per screen. Using a loaded labor rate of 

### $42.06/hr, this calculated out to be $40,378/year.
The added cost to run all ourtraveling screens in the continuousmode, over the present operation 

### is estimated to initially cost $1l0,577/year and then $79,777/year thereafter for power and labor. General items required for increased reliability include the following:


### 1

### - Thordon bearings for the headshaft 2. Stoodybearings for the footshaft 3. Increased screen adjustments(chain tension and shaft alignment) 

### 4. Increased 

### lubrications/inspections 5. Fiberglassbaskets (complete)
In summary, KeySpan has concludedthat continuous operation ofTraveling Screens,duringperiods ofpeak impingement, is a feasible operation with the existing screens. In order to maximize the benefits of increasing traveling screen operation and minimize the additional wear, while providing maximum benefit in terms 

### ofreducing fish impingement duration during times 

### of maximum impingement, plans could be made to 

### runthe screens at Glenwood and 

### Port Jefferson continuously duringthe months of October, November, and December, and atFar Rockaway duringthe months ofNovember and 

### May. Although Barrett and Northport Power Stations already runs their screens mostly in the continuousmode, the most critical months for Barrett with respect to impingement are April, October and November. The most critical months forNorthport areNovember, December, January and February. RWJ, 6-20-02

5