Document ID: EPA-HQ-OW-2008-0667-0106
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2011-02-23T05:00Z

Site Visit Report
                                       
Haynes Generating Station (HnGS)
6801 Westminster Avenue
Long Beach, CA 90803
September 2, 2009
Background and Objectives
The Environmental Protection Agency (EPA) is in the process of developing 316(b) cooling water intake structure requirements that reflect the best technology available (BTA) for minimizing adverse environmental impact for all existing power plants and manufacturing facilities. As part of this process, EPA staff is visiting electric generators and manufacturers to better understand the cooling water intake structure (CWIS) technologies in use at facilities, including the site-specific characteristics of each facility and how these affect the selection and performance of CWIS technologies.  EPA is also visiting facilities to better understand cooling water use and specific issues or technologies that can affect 316(b) compliance.  EPA selected Haynes Generating Station (HnGS) for a site visit due to its coastal location near the Pacific Ocean and its recent repowering project. 
Facility Description
HnGS is a natural gas - fired steam electric generating facility located in the City of Long Beach in Los Angeles County (a small portion of the facility property lies within the City of Seal Beach, Orange County). HnGS is owned and operated by the City of Los Angeles Department of Water and Power (LADWP).  The facility occupies approximately 160 acres of an industrially zoned site approximately 2 miles northeast of the entrance to Alamitos Bay.  The property parallels the east bank of the San Gabriel River for approximately (3/4) mile north of 2[nd] Street to State Highway 22.  The eastern edge of the property is bounded by the Orange County Flood Control District Channel.
AES's Alamitos Generating Station lies opposite HnGS on the west bank of the San Gabriel River.  A large residential neighborhood, Leisure World, lies across the flood control channel and extends the entire length of Haynes' eastern boundary.  Another residential neighborhood, Island Village, lies southeast of the facility's southern boundary.
Elevation at the site is relatively flat, with most of the site situated between 10 and 15 feet above sea level (asl).
The southern portion of the property is occupied by the generating units, parking areas, switchyard, and active fuel storage tanks, as well as miscellaneous storage and maintenance buildings.  Large fuel storage tanks used to occupy the northern portion of the property, although they have since been decommissioned and removed.  This area has been set aside by LADWP for the next planned repowering phase due to commence construction in January 2011, consisting of six 100 MW simple cycle combustion turbines with dry cooling.

Wastewater discharges to the San Gabriel River and water withdrawals from Alamitos Bay are covered under NPDES Permit No. CA0000353, which is administered at the state level by a regional water board.  Order No. 00-081, issued by the Los Angeles Regional Water Board, expired on May 10, 2005 but has been administratively continued to the present.  The facility had been previously notified that a reissued permit was delayed pending the outcome of the State Water Board's ongoing once-through cooling policy development.  At the time of EPA's site visit, it was unclear when the NPDES permit would be reissued.
Power generation began in 1962-3 with the commissioning of Units 1 & 2.  Units 5 & 6 were commissioned in 1966-7.  Units 3 & 4 have been decommissioned and retired and were replaced by combined cycle generating units (Units 8, 9 and 10) in 2005.
Haynes currently has 165 employees.
Electricity Generation and Transmission
HnGS currently operates four conventional steam turbine units (Units 1 & 2, 5 & 6) as well as one combined cycle system that consists of two combustion turbines (Units 9 and 10) and a heat recovery steam generator (HRSG)(Unit 8).  The combined generating capacity for HnGS is approximately 1,625 MW (Table 1).

Facility representatives noted that, with the exception of Units 8, 9 and 10, the capacity utilization rate (CUR) at HnGS has consistently trended downward over recent years as more modern and efficient sources have come online in the region, including an expanded renewable portfolio to meet state greenhouse gas objectives.  However, depending upon federal and state climate legislation, greater dependence on these local plants for base load energy supply and the balancing of new intermittent renewable resources may be necessary if LADWP is required to undertake an early divestiture of its coal resources.
                        Table 1  - HnGS Rated Capacity
Unit
Rated capacity
(MW)
2008 CUR
Unit 1
                                      230
                                      13%
Unit 2
                                      230
                                      13%
Unit 5
                                      330
                                     7.3%
Unit 6
                                      260
                                     7.3%
Unit 8
                                      575
                                      41%
HnGS total
                                     1625
                                      25%

Energy efficiencies for HnGS's four natural-gas fired units are typical for units of this type and age.  Under peak conditions, Units 1 and 2 can operate at approximate efficiencies of 33% (9,650 BTU/kWh) while Units 5 & 6 which are supercritical units are slightly more efficient at 36% (9,400 BTU/kWh).  The combined cycle units, taken as a whole, operate more efficiently than conventional steam boiler units.  Under optimal conditions, the Unit 8, 9 and 10 efficiency can reach 50% or higher (6,800 BTU/kWh). 
LADWP representatives noted that capacity utilization rates are an inexact metric for determining a particular facility's importance to the overall system.  Although HnGS's overall CUR is relatively low, it occupies a critical position in LADWP's overall generation and transmission plans during peak periods.  The existing transmission system is limited in its ability to move electricity between the northern and southern sections of LADWP's service areas during high demand periods.  The physical location of HnGS, along with LADWP's other coastal units, enables LADWP to maintain a proper balance in the system without compromising service.  This is particularly notable since LADWP is its own balancing authority and as mentioned in Section 10 of this report, as a vertically integrated utility responsible for its own generation, transmission, and distribution of electricity, does not rely on the energy market for power purchases to supply its energy needs.  Therefore, LADWP believes that its coastal plants serve a critical function in providing local resource adequacy, reliability, and system stability.
Cooling Water System and Intake Structure
All steam units at HnGS, including the Unit 8 HRSG, use ocean water for condenser cooling in a single-pass configuration ("once-through cooling"). 
HnGS operates one CWIS to provide condenser cooling water to each of the five generating units.  Water is withdrawn from San Pedro Bay, via Alamitos Bay through seven openings in a bulkhead wall in the northeast corner of the Long Beach Marina.  Seven 8-foot diameter pipes (only six are typically used) lead under the San Gabriel River to a manmade canal extending 1.5 miles northeast to the station, where six separate screenhouses draw water from the canal.
The screenhouses for Units 1 and 2 are identical, with each containing two screen bays fitted with stationary screens.  Each screen is 10 feet wide with 3/8-inch wire mesh panels.  Velocities at the screens are reported to be 0.9 feet per second (fps).  Downstream of each screen is a circulating water pump rated at 48,000 gallons per minute (gpm), for a total capacity of 192,000 gpm, or 276 million gallons per day (mgd).
The screenhouses for Units 5 and 6 are identical, with each consisting of four screen bays fitted with vertical traveling screens (Figure 1).  Each screen is 8 feet wide with 3/8-inch wire mesh panels.  Velocities at the screens are reported to be 0.8 feet per second (fps).  Screens are normally rotated and cleaned once every 8 hours.  A high-pressure spray removes any debris from the screens, including impinged fish, for disposal at a landfill.  Two circulating water pumps for each unit are located downstream of the screens, with a design rating of 80,000 gpm, for a total capacity of 320,000 gpm, or 461 mgd.
Unit 8 uses the two screenhouses previously used by Unit 3 and Unit 4.  Each screenhouse consists of two screen bays (Figure 2).  Each screen is 10 feet wide with 3/8-inch wire mesh panels.  Velocities at the screens are reported to be 0.7 feet per second (fps).  Screens are normally rotated and cleaned once every 8 hours.  A high-pressure spray removes any debris from the screens, including impinged fish, for disposal at a landfill.  Two circulating water pumps for each unit are located downstream of the screens, with a design rating of 40,000 gpm for a total capacity of 160,000 gpm, or 230 mgd.  The total design intake flow (DIF) for HnGS is 967 mgd.

                                       
Figure 1  -  Plan View Unit 5 & 6 Screenhouse

Figure 2  -  Unit 8 Screenhouse
Data provided by HnGS representatives shows the average daily intake flows from 2005 through 2008 (Table 2).
Table 2  -  Average Annual Intake Flows
Year
Average Annual Intake Flow (mgd)
Percentage of DIF
2005
                                      775
                                      80
2006
                                      772
                                      80
2007
                                      619
                                      64
2008
                                      738
                                      76

A direct correlation between flow and generating capacity utilization cannot be easily made since generating CUR do not account for startup/shutdown periods, nor do they account for "hot standby" periods during which units are held in a near-ready state without generating electricity but still require cooling water withdrawals.
HnGS conducts periodic heat treatments to control biofouling (e.g., mussel growth) in the cooling water system, although these occur infrequently.  During heat treatment control gates on the intake and discharge tunnels are closed while a bypass gate is opened allowing all water to recirculate through the system until the temperature has reached 115° F and has circulated for 120 minutes. 
Biofouling is also controlled through periodic chlorine (sodium hypochlorite) injections to the intake flow.  Chlorination occurs at each unit for 40 minutes twice per day.
Impingement and Entrainment Information
Following the adoption of the Phase II rule, HnGS initiated compliance activities by submitting a Proposal for Information Collection (PIC) in October 2005 that outlined plans to conduct a source water characterization study.  Impingement and entrainment technologies would also be evaluated for their potential use at the site.  The PIC identified fine-mesh traveling screens, cylindrical wedgewire screens, operational measures, modular inclined screens and restoration as technologies that might offer some benefit to HnGS.  These evaluations were not completed, however, due to the suspension of the Phase II rule. 
At the direction of the Regional Water Board, HnGS conducted a source water characterization study in 2006 to determine the composition and abundance of all life stages of fish and shellfish that might be influenced by the intake structure (baseline characterization study).  HnGS collected data from nine source water sampling locations: six in San Pedro Bay and three in Alamitos Bay.  HnGS collected monthly sampling every six hours in a 24 hour period at each location which allowed for diel characterization.  As part of this study, HnGS also conducted impingement and entrainment sampling.  HnGS collected impingement samples at the traveling screen for each unit four times per week during 2006.  HGSHNGS conducted biweekly entrainment sampling in front of the bulkhead at the Long Beach Marina.  Facility representatives stated that 95% of the entrained fish were forage fish (gobies and blennies).  HnGS published the study in November 2007.
Because HnGS does not employ any technologies specifically designed to reduce impingement or entrainment, detailed effectiveness studies have not been performed on the current cooling system.
Cooling Tower Feasibility
Facility representatives noted that the feasibility of cooling towers at the HnGS location has been considered at different points, whether as part of a repowering project or to retrofit one of the existing units.  HnGS has not conducted a formal cost and engineering feasibility analysis, however.
A report prepared for the California Ocean Protection Council (OPC) and State Water Board in 2008 identified several obstacles that would influence the feasibility of cooling towers at the HnGS location.  Sufficient space is available at the existing location, primarily in the area where fuel oil tanks have been removed.  Visual impacts in this location would likely be limited given the industrial nature of most of the surrounding area.  The proximity of residential neighborhoods in Seal Beach, however, would likely require noise mitigation measures, such as fan deck barrier walls and grade-level barrier walls.
The 2008 OPC study considered these obstacles and configured three separate cooling towers on the northern portion of the facility with appropriate noise abatement technologies.  The initial capital cost for these towers was estimated at $152 million, excluding long-term costs such as operation and maintenance and energy penalty costs.
During the site visit, facility representatives noted that opposition from residents in nearby neighborhoods was likely to be significant if cooling towers were planned for HnGS, citing the opposition during the Unit 8 repowering project.  Representatives also noted that since the OPC study was issued, LADWP has decided to move forward with a repowering project to replace Units 5 & 6 using much of the old tank farm area for the replacement units.  This project, consisting of six combustion turbines with dry cooling, is slated to commence around January 2011.  Most significantly, however, representatives noted that retrofitting the existing once-through cooling systems for Units 1 & 2, 5 & 6 with cooling towers made little economic sense given the age and capacity utilization of each unit.
Debris Handling
Screens at HnGS can collect notable amounts of debris following storm events, although floating booms in the intake canal can provide some control.  Any debris captured on the bar racks or traveling screens is disposed of in a landfill. 
Repowering/Future Uses
LADWP completed the Unit 3 & 4 repowering project in 2005, replacing these units with the Unit 8, 9 and 10 combined cycle system using the existing (once-through) cooling system from Units 3 and 4.  The new unit consists of two gas combustion turbines and the HRSG.  The replacement unit generates electricity at an efficiency rate 30 to 40 percent higher than Units 3 & 4, reducing per-unit fuel consumption, greenhouse gas emissions and NOx emissions.
LADWP is also pursuing a repowering project for Units 5 & 6 that would retire those units and replace them with 6 quick-start gas combustion turbines with a total capacity of 600 MW.  The gas turbines would be located on land previously occupied by fuel oil tanks and might complicate placement of any cooling towers for other units.  Facility representatives noted that this project would likely be air cooled.
Cooling Ponds
HnGS does not use cooling ponds for condenser cooling.
Ownership
LADWP is the largest municipally owned utility in the country with a service population of approximately 4 million people.  LADWP maintains a total generating capacity of approximately 7,200 MW from diverse portfolio of fossil, hydroelectric, renewable, and nuclear units.  HnGS is one of three LADWP-owned facilities on the California coast that continues to use once-through cooling (together with the Harbor and Scattergood Generating Stations). 
As a vertically integrated utility, LADWP owns and operates the generating, transmission and distribution systems that provide electricity to a dedicated customer base.  This transmission system is not limited to the City of Los Angeles, but extends into Nevada, Utah, and Arizona.  The system is used to import power to all locations (LADWP owned and power exchanges with other utilities).  This differs from many investor-owned utilities, such as Pacific Gas & Electric or Southern California Edison, which must rely on the open market to procure a significant portion of their electricity needs.  LADWP must obtain approval from the Los Angeles City Council to implement any electricity rate increases.
LADWP is in the process of developing a new Integrated Resource Plan (IRP) and is currently soliciting input from the public on this new guidance document.  This new 2010 IRP will help set the course that LADWP will take in determining the best path to take for repowering the existing OTC facilities.
316(a)
Thermal discharges to surface waters are governed by the state's Thermal Plan (1972), which creates separate requirements for new and existing thermal discharges to ocean waters.  As an existing thermal discharger, HnGS is subject to the Thermal Plan's narrative requirement that any thermal discharge must ensure protection of identified beneficial uses.  This requirement is incorporated into the existing permit as a temperature limitation of no more than 100° F during normal operation and 120°F during heat treatments.  The facility does not have a 316(a) variance for thermal discharges and has complied with the existing limitation during its most recent permit cycle. 
HnGS was notified that the San Gabriel River was being reclassified from an ocean to an estuary-type receiving water.  Under the Thermal Plan, thermal discharges would be limited to no more than 20° F above the background and may not exceed 86° F.  LADWP has disputed the Regional Board's interpretation and has conducted hydrodynamic studies which affirm LADWP's claim that the San Gabriel River at the point of discharge is characteristic of an enclosed bay rather than an estuary, which would entail less stringent thermal discharge limits. 
Ash Handling
HnGS does not generate any ash.
Air Emissions Controls
Units 1, 2, 5 and 6 each employ selective catalytic reduction to minimize NOx emissions.  The gas combustion turbines that are part of the Unit 8 combined cycle system employ dry low NOx burners in addition to selective catalytic reduction.
Additional Information
Facility representatives noted that an ongoing legal battle over the availability of emission credits within the South Coast Air Quality Management District have raised the possibility that no new projects would be able to obtain the necessary air permits.  This would include facilities retrofitted with wet cooling towers.
HnGS's current NPDES permit, adopted in 2000, does not contain any numeric or narrative limitations regarding impingement or entrainment due to cooling water withdrawals.  The permit carries over findings from previous permits that essentially concluded the HnGS cooling water system represented the "best technology available" for compliance with 316(b).  Although these determinations were made prior to the adoption of the state policy on once-through cooling, future studies will determine whether this statement is still accurate or whether other technologies are available that would represent "best technology available" with costs that can be borne by industry.  HnGS is required to conduct semi-annual impingement monitoring coinciding with scheduled heat treatments. 
In addition to once-through cooling water, HnGS discharges a small volume of wastewater from several low volume waste streams.  These low volume wastes consist of boiler blowdown, floor drains, metal cleaning wastes (chemical and non-chemical) and settling basin discharges, and are commingled with once-through cooling water prior to discharge through one of 6 permitted outfalls.  All wastewater is discharged the San Gabriel River and eventually to the Pacific Ocean.
Domestic wastewater is captured in portable Baker tanks and disposed of and treated offsite. 
HnGS must comply with both water quality-based and technology-based effluent limitations for its wastewater discharge to the San Gabriel River.  In 1988, the State Water Board granted a variance to the total residual chlorine water quality standard for biofouling control in the cooling system.  EPA granted a similar variance for the total residual chlorine effluent limitation applicable to steam electric facilities.  It is not clear if these variances will be revisited in any future permit reissuance.
As noted in Section 11.0 above, under the current NPDES permit for HnGS, the San Gabriel River at the point of discharge is considered part of the Pacific Ocean.  Thus, water quality-based limitations are addressed by the state's Ocean Plan.  Reclassification of the receiving water from ocean to either an estuary or an embayment, will mean that future water quality-based limitations will be derived from the California Toxics Rule. Limits under the CTR may be more stringent than existing limits for certain parameters (e.g., metals).

Attachments

Attachment A		List of Attendees
Attachment B		Site Photos
Attachment C		Facility Flows
Attachment D		Alden Report for Phase II Compliance (December 2004)
Attachment E		Addendum to Alden Report for Phase II Compliance (April 2007)
Attachment F		Impingement Mortality and Entrainment Study (November 2007)
Attachment G	Impingement Mortality and Entrainment Study Appendices (November 2007)

Attachment A--List of Attendees

Paul Shriner, EPA
Jan Matuszko, EPA
John Kemmerer, EPA Region IX
Tim Havey, Tetra Tech
Kelly Meadows, Tetra Tech
Ken Silver, LADWP
Vic Ybarra, LADWP
Kim Burmahln, LADWP
Susan Damron, LADWP
Dipak Patel, LADWP
Dawson Dong, LADWP
Ian Guthrie, LADWP
Katherine Rubin, LADWP

Also see attached materials for the sign-in sheet.

Attachment B -- Site Photos

                                       

                                       N
                                       

Attachment C -- Facility flows

Please see the attached materials.

Attachment D--Alden Report for Phase II Compliance (December 2004)

Please see the attached materials.

Attachment E	--Addendum to Alden Report for Phase II Compliance (April 2007)

Please see the attached materials. 

Attachment F	--Impingement Mortality and Entrainment Study (November 2007)

Please see the attached materials.

Attachment G--Impingement Mortality and Entrainment Study Appendices (November 2007)

Please see the attached materials.