4-50

Delineation Drilling Activities Offshore Santa Barbara County

gime by the total number of days of observations, 1804

days, which is approximately 5 years of data. From

this relatively strong data set we see that the:

· Upwelling Synoptic Flow Regime occurs 35.0

% of the year,

· Convergent Synoptic Flow Regime occurs 31.2

% of the year,

· Relaxation Synoptic Flow Regime occurs 27.0

% of the year, and

· transitional or “other” flows occur 6.8 % of the

year.

Understanding the monthly, seasonal, and annual frequency of these flow regimes helps to read

the real-time monitoring data from the MMS/Scripps

website in proper context” (Browne 2001).

4.4.5 WAVE CLIMATE OF THE SOUTHERN

CALIFORNIA BIGHT

Discussion of the wave climate of the Southern

California Bight is exclusively taken from Hickey 1993

and USDI, MMS 1991. Local wind driven waves and

long period swell formed by distant tropical storms

dominate the wave environment in the Southern California Bight. The Southern California Bight’s offshore

islands and ridges serve as a shelter for the coast from

the effects of deep ocean gravity waves. Much of that

energy is dissipated in island surf zones or reflected

back offshore.

Figure 4.4-15. Suface current vectors located at the

present MMS-SCRIPPS monitoring program

current mooring sites depicting the current flow at

these locations during the (a) upwelling, (b)

convergent, and (c) relaxation flow regimes (Dever

2000).

 Percentage of Total Days of Five

Five Years of Each Calendar Month Years of Each Calendar Month

 Month Days % Upwell % Conv % Relax % Other Upwell Conv Relax Other

 1.0000 155.0000 30.1613 26.1290 37.4194 6.2903 46.75 40.50 58.00 9.75

 2.0000 141.0000 51.7730 26.0638 19.1489 3.0142 73.00 36.75 27.00 4.25

 3.0000 154.5000 53.0744 33.9806 2.4272 10.5178 82.00 52.50 3.75 16.25

 4.0000 150.0000 86.0000 8.8333 2.6667 2.5000 129.00 13.25 4.00 3.75

 5.0000 155.0000 47.7419 32.0968 14.6774 5.4839 74.00 49.75 22.75 8.50

 6.0000 150.0000 44.6667 32.8333 17.3333 5.1667 67.00 49.25 26.00 7.75

 7.0000 155.0000 22.4194 32.0968 32.9032 12.5806 34.75 49.75 51.00 19.50

 8.0000 155.0000 28.8710 35.3226 27.5806 8.2258 44.75 54.75 42.75 12.75

 9.0000 152.0000 20.0658 36.3487 37.9934 5.5921 30.50 55.25 57.75 8.50

 10.0000 155.0000 19.0323 41.9355 32.7419 6.2903 29.50 65.00 50.75 9.75

 11.0000 135.0000 5.3704 33.5185 53.1481 7.9630 7.25 45.25 71.75 10.75

 12.0000 146.5000 9.2150 34.3003 49.3174 7.1672 13.50 50.25 72.25 10.50

 Total 1804.00 632.00 562.25 487.75 122.00

Table 4.4-2. Five year monthly frequency of the

upwelling, convergent, and relaxation flow

regimes. The columns are month (1-12 is Jan.-

Dec.), total days of observations within each

month, percent (%) upwelling, (%) convergence, (%)

relaxation, (%) other, total days for each of the

twelve months where upwelling, convergence,

relaxation and “other” occurred. The total days of

observations within each month are the number of

days for each month between Dec. 1993 and Nov.

1999 when SMIN, ANMI, and PAIN all returned

good velocity data (Dever 2000, Browne 2001).
4-51

Description of the Affected Environment: Physical Oceanography

The restricted fetches within the Southern California Bight allow only the development of locally wind

driven waves with relatively small amplitudes, short

periods, and short wavelengths. Also, because the important winds are the sea breezes, the duration is normally less than 10 hours. It is only when gale winds

blow from the west at 17 m/sec (38 mph) or more that

high waves are formed in the local region and travel

over the shelf. These are most common in the San

Pedro Channel where waves as high as 7.6 m (24.9 ft)

have been encountered.

The sheltering effect of the Northern and Southern Channel Islands is dramatically illustrated in data

collected at Begg Rock (located north of San Nicolas Island) and Sunset Beach (located just south of Palos

Verdes) wave monitoring sites. Spectral amplitudes are

an order of magnitude smaller at Sunset Beach than

they are at Begg Rock.

The dominant swell period at Begg Rock varies

from 14-18 seconds in winter to 5-10 seconds in summer. Long period swell can be generated from the

north, west, or south, but most long period winter

swell is generated by North Pacific storms. The summer wave spectra at Sunset Beach are dominated by

16-18 second long period swell coming from the southern hemisphere. Begg Rock is sheltered from swell

coming from the south.

Wave spectra during a major winter storm period are an order of magnitude greater than that of

waves occurring during a typical winter period. Severe waves such as these are usually generated from

storms that develop between Hawaii and the Pacific

coast. The dominant wave period is about 16 seconds. The amplitudes of these waves are significantly

reduced at the coast. Typically, waves impinging on

the Southern California Bight coastline generate a net

southeastward alongshore drift in the coastal surf

zone. This alongshore drift is responsible for much of

the sediment movement along the coast.

“The coastal area between Point Conception and

Ventura is the most protected from swell. Except at

Pt. Conception itself, swell cannot reach the area without considerable reduction by the Channel Islands or

extreme refraction over the mainland shelf. From

Ventura to Pt. Hueneme, swell cannot reach the area

without considerable reduction by the Channel Islands

or extreme refraction over the mainland shelf. From

Ventura to Pt. Hueneme, swell approaching from the

west arrives unchanged and has sometimes caused

substantial destruction along the shore. From Long

Beach to Newport significant swells arrive from the

west and south. From Newport to Oceanside, only

swell from the south arrives unchanged. The coast

near San Diego is the most exposed, especially to swell

from the south, which arrives without significant

modification.

Swell from the north boundary of the Pacific

High: This occurs when the high elongates and migrates to the south, most commonly in winter. Because of lower wind velocities swell from this source

is moderate.

Swell from Hawaiian lows: The source of these

swells is the low pressure centers developing in the

expanse of the Pacific Ocean north of Hawaii. These

develop most commonly in the spring and the height

of this swell is normally moderate, usually less than

2.5 m (8.2 ft).

Swell from storms in the Southern Hemisphere:

This swell is probably present about two-thirds of the

time but is so low that is masked by swell from other

areas. The effect is greatest in summer when storms

in the Southern Hemisphere are most intense and follow tracks which are further to the north.

Swell from tropical hurricanes: Very rarely,

tropical storms which develop off the coast of Costa

Rica may reach the waters off Southern California and

cause extensive damage. These storms usually dissipate long before that, but swell may arrive from the

areas where the storms develop. It is estimated that

heavy swell from this source may reach the Southern

California every four to five years, although more frequent occurrence is possible.

Waves and Swell from Local Cold Front Passages: These waves are characterized by their

choppiness and are always accompanied by strong

winds. Since the swells are generated in nearby surrounding areas, the sheltering effects of points, headlands, and islands is considerably reduced.

Tsunamis: The highest water levels along the

California coast are produced by tsunamis: long gravity waves which are generally produced by intense

submarine earthquakes. Tsunamis occur very infrequently and the damage is usually not extensive to

properly designed structures. Hazards from tsunamis include a variation in water level from 1.5 to about

4.5 m (4.5 to 13.5 ft) and possible high current velocities in shallow or restricted waters” (USDI 1991).

Tides: The tides are mixed with a semi-diurnal

constituent being more dominant than the diurnal

constituent. The time between successive highs or

lows vary between 10 and 14 hours. The barotropic

tidal wave advances towards the Southern California

coastline from the southeast along the coastline reaching Pt. Conception 1⁄2 hour after it arrived at San Diego.

Both cross-shelf and along-shelf tidal current velocities within the Southern California Bight (including the Santa Barbara Channel) are on the order of

10 cm/sec. Cross-shelf tidal currents are predominantly baroclinic (depth and density dependent)

whereas along-shelf tidal currents tend to be more

barotropic (depth dependent only). Maximum velocities along the vertical profile of these currents tend to
4-52

Delineation Drilling Activities Offshore Santa Barbara County

4.5 WATER QUALITY

REGULATORY SETTING

In 1972, Congress passed the Federal Water Pollution Control Act, which was reauthorized in 1977,

1981, 1987, and 2000 as the Clean Water Act (Pew

Oceans Commission (POC), 2001). The goal of the

law was to eliminate pollution in the nation’s waters

by imposing uniform standards on all municipal and

industrial wastewater sources based on the best available technology. Facilities discharging wastes at

discernable, or point, sources, were required to obtain permits from the U. S. Environmental Protection Agency (EPA) in the form of National Pollutant

Discharge Elimination System (NPDES) permits.

Overall, the NPDES program has resulted in dramatic

reductions in the amount of pollutants entering U. S.

waters, including coastal waters (POC, 2001). The

Southern California Bight (SCB), in particular, has

seen great reductions in pollutants over the past 25

years, including 50 percent for suspended solids, 90

percent of combined trace metals, and more than 99

percent for chlorinated hydrocarbons. Measurements

of sediments, fish and marine mammals all show decreasing contamination This has occurred despite

great increases in population and volumes of discharged wastewater (Schiff et al., 2000). This reduction as accomplished through source control, pretreatment of industrial wastes, reclamation and treatment

plant upgrades.

In August, 1999, a California Coastal Commission letter to the MMS raised seven issues of concern.

Amongst these was a question regarding changes in

water quality regulations and anticipated further

changes in these regulations. The following discussion addresses this concern.

1 EPA’s Region 9, with offices located in San Francisco, covers

California, Nevada, Arizona, Hawaii, and the Trust Territories.

See Region 9’s website at: http://www.epa.gov/region09/

reg9bck.html. Also, for more information on EPA’s nation-wide

NPDES program see the website at: http://www.epa.gov/owm/

npdes.htm#top.

2

 The CCC conditions are as follows: (1) Include effluent

standards for produced water based on the more stringent of

EPA criteria or California Ocean Plan criteria; (2) Revise the

maximum feasibility mitigation study requirement in the

permit; and (3) Inclusion in the fact sheet of a description of

EPA’s commitment concerning third party monitoring.

be at the surface and bottom boundary layers. Tidal

currents are larger in the upper 100m over the shelf

edges, slopes and open basins (15 – 20 cm/sec) than

they are over the shelf. Tidal currents in the island

passages of the Santa Barbara Channel tend to exhibit velocities four times greater reaching 50 cm/sec

during strong ebbs.

While offshore oil and gas does contribute to the

pollution of the ocean, effluent parameters are limited according to the limitations of the appropriate

NPDES permit issued by the EPA, Region 91. At

present, two types of permits exist to regulate effluents from the 23 offshore oil and gas facilities. One

type is a General permit and the other is a series of

Individual permits The General permit (referred to

hereafter as the “1984 General permit”) was issued

in 1983, reissued in January 1984, and expired in June

1984 with no new General permit to take its place.

This permit covers 14 platforms in the Pacific OCS

Region. The remaining nine platforms are presently

covered by Individual permits. However, two of the

Individual permits were issued in 1977 and have never

been updated, while the permits for the remaining

seven platforms were all applied after the 1984 General permit had expired. All the newer Individual

permits are more stringent and cover a wider array of

effluents than the 1984 General permit.. Of the 23

platforms, only four facilities are operating under permits that contain the more stringent effluent guidelines for the Offshore subcategory of the Oil and Gas

Extraction Point Source Category promulgated on

March 4, 1993 (58FR12454). At this time, all facilities are operating under expired individual or general

permits, that have been administratively extended

pursuant to the 40 CFR 122.6.

To rectify this inequitable permit situation, EPA,

Region 9 began, in October 1996, the process of issuing a new General permit (referred to hereafter as

the “new General permit. In January 2001, the new

General permit received California Coastal Commission (CCC) Consistency Certification, albeit with conditions2

. At present, EPA is considering how to handle

the conditions and how to reissue the changed permit. There is no anticipated date of reissuance.

In general, the new General permit is more stringent than either the 1984 General permit or any of

the Individual permits. Table 4.5-1 illustrates this by

comparing the 1984 General permit with the draft limitations of the new General permit. The Individual

permits are by and large more stringent than the 1984

General permit by decreasing limits on some components of produced water, requiring more frequent

monitoring, and monitoring an increased total number of effluents. In part, the greater number of effluents is a reflection of the increased sophistication of

offshore oil and gas activities. As can be seen, the current General permit regulated 12 discharges while the

new draft permit will regulate those and 10 others.

A key aspect of the regulatory regime for water

quality is compliance monitoring. In 1989, MMS, Pacific OCS Region and EPA, Region 9 signed a Memorandum of Agreement (MOA) detailing the role each

agency would play in conducting NPDES inspections

and sampling at the offshore oil and gas platforms.
4-53

Description of the Affected Environment: Water Quality

The centerpiece of the MOA is the workplan, created

annually by EPA and MMS. The workplan gives the

details of the inspection and sampling efforts and includes the number, location, and type of samples to be

taken. Which platforms are to be sampled for the year

is closely held since all inspections and sampling are

unannounced.

Violations of any permit limit can be treated in

several ways by EPA. The most common is for EPA

and the operator to determine the cause of the violation and to take steps to avoid future occurrences.

Further actions by EPA, such as fines or other sanctions, would be determined at EPA’s discretion depending on the specific aspects of the event.

The State of California developed a comprehensive water quality pollution control plan in 1972 called

the California Ocean Plan (California State Water Resources Control Board, 1997). It is required that the

plan undergo a triennial review. The plan was last

issued in 1997, thus, the plan is currently undergoing

review. The plan, which covers any facility that discharges into California State waters, up to 3 miles from

shore contains several categories including Effluent

Limitations, Water Quality Objectives, and Objectives

for Protection of Human Health (Non-carcinogens and

Carcinogens). Combined, these catego ries apply limits to 84 pollutants.

The U. S. Coast Guard (USCG) also regulates

offshore oil and gas platforms in several ways, including when pollution events occur. For example, an oil

sheen, a violation of USCG regulations, could result

in an enforcement action. The USCG does regulate

the spillage of oil in the Federal OCS (and State waters), although it is not regulated under NPDES regulations or permits.

Regional Setting: This section describes the water quality in the area potentially impacted by the proposed action (delineation drilling) and, in addition, includes a description of resources in a larger area that

could potentially be affected by oil spills resulting from

the development of the 36 undeveloped leases.

Water pollution has existed along the Pacific

coast since urban centers and industrial complexes

were built along the shores and rivers. Regulated

pollution sources primarily include treated sewage

outfalls and heated water outfalls from power plants

(chlorine is sometimes used in these to reduce fouling). Nonregulated pollutant sources include storm

drains, rivers, and other nonpoint source runoff

sources. Pollutants from these sources have included

chemicals, such as pesticides and manufacturing

wastes, oil and rubber from vehicles, general trash

and garbage and many other types of materials. In

addition, agriculturally-based materials from rural

areas, including animals wastes, pesticides and herbicides and soil can be washed into nearby streams and

rivers and the oceans.

The 1975-1978 BLM-sponsored baseline studies

in the Southern California Bight (SCB) indicated that

most of the metal and hydrocarbon loads of the four

basins examined (Santa Barbara Channel, San Pedro,

Santa Monica, and San Nicolas) were derived from

industrial and municipal wastes, entering the marine

environment through direct discharge, indirect runoff and atmospheric transport, all centering around

the Los Angeles metropolitan area (BLM, 1979).

Lead was the only metal that reached the Santa

Barbara Channel Basin in anything but natural

amounts (BLM, 1979). Lead, apparently, is more susceptible to atmospheric transport, and was thus carried to the far reaches of the SCB from the sources

(primarily industry and automobile gasoline exhaust).

Age-dated box cores revealed that rates of lead deposition in the Santa Barbara Channel Basin is decreasing (as of 1978). This, despite the fact that this Basin

has the greatest sedimentation rate of any of the four

basins examined (San Pedro, Santa Monica and San

Nicolas are the other three).

Analysis of hydrocarbons in the SCB showed significant increases over the last 50 years (as ascertained

using age-dated box cores). In part, this increase was

due to pulses of natural seepage, however, the majority was attributed to man-related combustion and sewage outfall sources. BLM (1979) noted that the degree of anthropogenic input to the Santa Barbara

Channel Basin is relatively constant in recent years.

Relative contributions from natural seepage were the

highest for the Santa Barbara Channel Basin and least

for the San Nicolas Basin, while combustion-derived

sources were the most for the San Nicolas Basin, followed by the San Pedro and Santa Monica Basins and

the least for the Santa Barbara Channel Basin.

Sources of pollution to the sea from offshore include shipping (for example, bilge and tank cleaning

and treated sewage), recreational boating (such as oil,

diesel, and general garbage) and oil and gas facilities,

albeit under the limitations of NPDES permits (see

regulatory setting discussion, above).

Standard water quality parameters for the study

area, including temperature, salinity, dissolved oxygen, pH, nutrient concentrations, turbidity, and organic material, have previously been described in

Dames and Moore (1982), SAI (1984), Arthur D. Little

(1984), and Chambers Group 1987 (a, b). These parameters and some basic characteristics are given in

table 4.5-3.

Water quality in the study area may be generally divided into two subregions:

• Point Lobos to the western entrance of the

Santa Barbara Channel; and

• The northern Southern California Bight

(SCB): Santa Barbara Channel to Point

Fermin, including the offshore islands.
4-54

Delineation Drilling Activities Offshore Santa Barbara County

Effluent Current General Permit Limits Draft General Permit Limits

001 Drilling Discharges

(mud and cuttings)

Once/mud system toxicity test if 

unapproved mud are discharged1

Monthly volume estimate

Continuous constituent and additive 

inventory

No discharge of oil-based drilling mud

Annual report of heavy metal 

contaminants in barite

Use of generic mud

Daily visual sheen observation

End-of-well toxicity test

Volume limits applied to each platform

Continuous constituent and additive 

inventory

No discharge of oil-based drilling mud or 

mud contaminated with diesel

Limits on cadmium and mercury in barite

Use of generic mud

Static sheen test

002 Produced Water Monthly oil and grease samples

Monthly flow estimate (daily max = 72 

mg/l)

Yearly metals and phenols analysis

Weekly oil and grease samples (29 mg/l 

monthly average; 42 mg/l daily max.)

Flow limits applied for each platform

Quarterly monitoring of metals and other 

parameters

Whole effluent toxicity (chronic)

003 Well Treatment,

Completion and

Workover Fluids

Volume monitoring

No discharge of free oil monitored by 

visual observations

Volume monitoring

No discharge of free oil monitored by 

static sheen test

Once per job oil and grease samples (29 

mg/l monthly average; 42 mg/l daily 

max.)

004 Deck Drainage Volume monitoring

No discharge of free oil monitored by 

visual observations

Volume monitoring

No discharge of free oil monitored by 

visual observations

005 Sanitary and

Domestic Wastes

Flow rate

Residual chlorine

(not needed for facilities permanently

manned by less than 10 persons)

Sanitary Wastes (For facilities with less

than 10 persons):

Flow rate

Observation of floating solids.

(For facilities with 10 or more persons):

Flow rate

Total Residual Chlorine (minimum of 1 

mg/l, (as close as possible); maximum 

concentration of 10 mg/l.

Domestic wastes

Foam

006 Blow-out Preventer

Fluid

No free oil in the receiving water No free oil in the receiving water

Floating solids and foam

007 Desalination Unit

Discharge

No free oil in the receiving water Floating solids and foam

008 Fire Control System

Test Water

No free oil in the receiving water Chemical inventory

Chlorine (for antifouling)

Floating solids and foam

009 Noncontact Cooling

Water

No free oil in the receiving water Flow rate

Chemical inventory (if chemicals are used

in the effluent)

Chlorine (for antifouling)

Floating solids and foam

010 Ballast and Storage

Displacement Water

No free oil in the receiving water Flow rate

No free oil in the receiving water

Floating solids and foam

Table 4.5-1. Comparison of effluent limitations between the old (1984) general permit and the new

proposed general permit.
4-55

Description of the Affected Environment: Water Quality

011 Bilge Water No free oil in the receiving water Flow rate 

No free oil in the receiving water 

Floating solids and foam 

012 Boiler Blowdown Not in permit Floating solids and foam 

013 Test Fluids Not in permit Flow rate 

No free oil in the receiving water 

Chemical inventory 

Floating solids and foam 

014 Diatomaceous Earth 

Filter Media 

Not in permit No free oil in the receiving water 

Floating solids and foam 

015 Bulk Transfer 

Material Overflow 

Not in permit Floating solids and foam 

016 Uncontaminated 

Water 

Not in permit Floating solids and foam 

017 Water flooding Not in permit No free oil in the receiving water 

Chemical inventory 

Floating solids and foam 

018 Laboratory wastes Not in permit No free oil in the receiving water 

Floating solids and foam 

019 Excess Cement 

Slurry 

No free oil in the receiving water Flow rate 

No free oil in the receiving water 

Floating solids and foam 

020 Muds, Cuttings and 

Cement at Seafloor 

Not in permit No free oil in the receiving water 

Floating solids and foam 

021 Hydrotest water Not in permit Flow rate 

No free oil in the receiving water 

Chemical inventory 

Chlorine 

Floating solids and foam 

022 H2S Gas Processing 

Waste Water 

Not in permit Flow rate 

No free oil in the receiving water 

Floating solids and foam 

1

Operators commonly conduct toxicity tests on drilling mud whenever they are discharged into the sea. 

Table 4.5-1. Comparison of effluent limitations between the old (1984) general permit and the new

proposed general permit (continued).
4-56

Delineation Drilling Activities Offshore Santa Barbara County

Table 4.5-2. Relevant studies examining water quality in the study area.

Area of Study Citation 

Southern California Anderson, J. W., D. J. Reish, R. B. Spies, M. E. Brady, and E. W. Segelhorst. 1993. 

Human impacts on the Southern California Bight. Chapter 12, in, M.D. Dailey, D. 

J. Reish, and D. W. Anderson (eds.), Ecology of the Southern California Bight: A 

synthesis and interpretation. 

Northern Santa Barbara County Arthur D. Little (ADL). 1985. Union Oil Project/Exxon Project Shamrock and 

Central Santa Maria Area Study EIS/EIR (and appendices). Prepared for County 

of Santa Barbara, Minerals Management Service, California State Lands 

Commission, California Coastal Commission, and California Office of Offshore 

Development. 

Santa Barbara County ADL. 1984a. Point Arguello Field and Gaviota Processing Facility Area Study 

and Chevron/Texaco Development Plans EIR/EIS. Final Report. Prepared for: 

County of Santa Barbara, U.S. Minerals Management Service, California State 

Lands Commission, California Coastal Commission, California Secretary of 

Environmental Affairs. 

Santa Barbara County ADL. 1984b. Point Arguello Field and Gaviota Processing Facility Area Study 

and Chevron/Texaco Development Plans EIR/EIS. Appendix H. Marine Water 

Resources. Prepared for: County of Santa Barbara, U.S. Minerals Management 

Service, California State Lands Commission, California Coastal Commission, 

California Secretary of Environmental Affairs. 

Southern California Bureau of Land Management (BLM). 1979. Natural and Anthropogenic Fluxes 

of Chemicals into the Southern California Bight as Related to the Potential 

Impacts of Offshore Drilling. Southern California Baseline Study, Benthic, Year 

Two, Volume II, Report 24.0. Robert F. Shokes and Paul J. Mankiewicz 

(authors), Science Applications, Inc., La Jolla, California. BLM/DOI Contract 

No. AA550-CT6-40. 

Southern California BLM. 1978. 1975/1976 Southern California Baseline Study and Analysis. Vol. 

II, Integrated Summary Report. Robert F. Shokes and Richard A. Callahan 

(authors), Science Applications, Inc., La Jolla, California. BLM/DOI Contract 

No. 08550-CT5-52 

Santa Barbara County –Santa 

Barbara Channel 

Chambers Group, Inc. 1987a. Final Supplemental Environmental Impact Report 

for the Exxon Santa Ynez Unit Offshore Oil Development Proposal. Prepared 

for: California State Lands Commission. 

Santa Barbara County –Santa 

Barbara Channel 

Chambers Group, Inc. 1987b. Finalizing Addendum. Final Supplemental 

Environmental Impact Report of the Exxon Santa Ynez Unit Offshore Oil 

Development Proposal. Prepared for: California State Lands Commission 

Southern California Minerals Management Service. 1996. Outer Continental Shelf Offshore Oil and 

Gas Leasing Program: 1997 -–2002. Final Environmental Impact Statement. 

August 1996. 2 Vols. 

General National Research Council. 1983. Drilling Discharges in the Marine 

Environment 

Santa Barbara County –Santa 

Barbara Channel 

Science Applications, Inc. 1984. Final Environmental Impact Statement/Report. 

Technical Appendix 12: Marine Water Quality for the Santa Ynez Unit/Las 

Flores Canyon Development and Production Plan 

Southern California Valerie Raco-Rands. 1996. Characteristics of Effluents from Small Municipal 

Wastewater Treatment Facilities in 1995 (in SCCWRP, 1996) 

Southern California Valerie Raco-Rands. 1998. Characteristics of Effluents from Large Municipal 

Wastewater Treatment Facilities in 1996 (in SCCWRP, 1998) 

General James P. Ray and F. Rainer Engelhardt (eds.). 1992. Proceedings of the 1992 

International Produced Water Symposium. February 4-7, 1992, San Diego, 

California. 
4-57

Description of the Affected Environment: Water Quality

Area of Study Citation 

Northern Santa Barbara County URS Company. 1986. San Miguel Project and Northern Santa Maria Basin 

Area Study Final EIS/EIR (and appendices), Cities Service Oil and Gas 

Corporation and Celeron Pipeline Company of California. Prepared for County 

of San Luis Obispo County, County of Santa Barbara, Minerals Management 

Service, California State Lands Commission, California Coastal Commission, 

and California Office of Offshore Development. 

These subregions are loosely based on the level

of activity that is occurring both onshore and offshore.

For example, traveling from north to south, population, shipping traffic, nonpoint pollution sources, and

on- and offshore oil and gas activities increase, while

river runoff generally decreases. These factors result

in a general increase in pollution. The Point Sal,

Purisima, and Bonito Units can be considered to be

in the first subregion, above, although the Bonito Unit,

located west of Point Conception, can be considered

to be in a transition zone from the Santa Maria Basin

and to the Santa Barbara Channel proper. The Gato

Canyon Unit is in the north-central Santa Barbara

Channel; thus, in the second subregion, above.

Point Lobos to the western entrance of the Santa

Barbara Channel. The California coast south of Point

Lobos is, relative to southern California urban centers, sparsely inhabited with little industrial development and more agriculture and ranching (MMS, 1996).

Only two Publicly-Owned Treatment Works (POTWs),

or sewage treatment plants, discharge directly into

the Pacific Ocean in San Luis Obispo County (table

4.5-4). Three others discharge into local rivers discharge into the ocean. All the dischargers are small,

according to EPA criteria (less than 25 million gallons per day [mgd]).

The Santa Maria River, on the border of Santa

Barbara and San Luis Obispo Counties, and the Santa

Ynez River, which flows into the ocean between Points

Purisima and Arguello, are the major sources of pollution that could exist in the San Luis Obispo/northern Santa Barbara County area. Contaminants and

nutrients in runoff from rivers are influenced by three

factors (NRC, 2001):

• Land uses (for example, whether the primary

use of the land is forested, agricultural, industrial or urban;

• Human activities that involve the application

of fertilizers, pesticides and the generation of

wastes;

• Natural phenomena and land-use decisions

that affect water infiltration, groundwater

movement, runoff, and transport in streams

and rivers.

Pollutants that could be associated with these

rivers are predominantly agriculturally based and may

include dairy and ranching-related pollutants (for example, animal wastes) and pesticides. During winter,

high runoff periods associated with storm and rain

conditions followed by upwelling-favorable winds have

driven these river plumes south past Point Conception and to the vicinity of San Miguel Island (Hickey

and Kaschel, unpubl.).

The paradox of these plumes is that the higher

the flow, the greater the dilution. Additionally, the

only time the plumes would reach to the vicinity of

the outer continental shelf would be during times of

high flow. Thus, pollutants carried by the plume would

be well-diluted, but perhaps still detectable, in the

offshore area.

For most of the central California coast, there

are no oil and gas activities. Marine terminals at

Morro Bay, Avila Beach and Gaviota have all been removed. The most northern marine terminal, and the

only one in the Santa Barbara Channel is at Ellwood.

The most northern offshore oil and gas facility is Platform Irene, located just northwest of Point Arguello.

There may also be natural oil and gas seeps along the

central California coast, but there is little information on these. The primary seepage zones are all found

at Point Conception and south (see below).

There is little information regarding the fate of

pollutants that are discharged into this subregion, in

part due to the overall lack of pollution. For this subregion, there is no evidence for such mechanisms as

uptake and bioaccumulation of some anthropogenicbased materials such as mercury and certain pesticides, and DDT to occur.

Thus, due to the low population density, lack of

major industries and intermittent high-flow river runoff, the Santa Maria Basin area and points north has

good water quality.

Santa Barbara Channel to Point Fermin. Pollution in the Santa Barbara Channel and south, along

the Malibu coastline, is probably greater than north

of Point Conception, although no studies have been

conducted to quantitatively ascertain this. Nevertheless, increases in population and pollution sources

would indicate that this statement is true qualitatively.

Overall, there are 24 discrete sources of pollution from

Point Conception to Point Fermin including six sewTable 4.5-2. Relevant studies examining water quality in the study area.
4-58

Delineation Drilling Activities Offshore Santa Barbara County

age dischargers, two power plants, six industrial waste

dischargers and 10 sources of runoff (Anderson et al.,

1993). The largest fresh water inputs are the Santa

Clara and Ventura Rivers and the Oxnard municipal

wastewater treatment plant (MMS, 1996).

In general, water column particulates and

benthic sediments in the southern California OCS

reflect the chemistries of their source materials (BLM,

1978). Surface waters located in the inshore areas

usually contain only fine-grained materials mixed with

planktonic organisms while the near-bottom waters

can hold a various assortment of materials in suspension from downslope transport processes (for example,

turbidity flows). These inshore waters were found to

have a preponderance of land-derived materials whose

metal contents have been influenced by anthropogenic

sources (BLM, 1978).

Indicators of Pollution. The Natural Resources

Defense Council (NRDC) published its 10th Annual

report entitled, “Testing the Waters 2000: A Guide to

Water Quality at Vacation Beaches” on August 3, 2000

(NRDC, 2000; Los Angeles Times, 2000). This report

listed the number of nationwide beach closures due

to pollution for 1999. The data were collected by EPA

as part of its BEACH (Beaches Environmental Assessment, Closure and Health) program and was based

on responses from over 100 agencies to EPA’s questionnaire. Of the six southern California counties from

San Luis Obispo to Los Angeles, Santa Barbara County

had the largest number of closings, 1392 days; followed

by Los Angeles, 460; Ventura, 257; and San Luis

Obispo, 4. The closings were commonly posted due to

high bacteria counts (fecal coliform). The majority of

these closings were attributed to pollutants brought

to the coast by river runoff.

The National Oceanic and Atmospheric

Administration’s National Status and Trends Program

(NS&T) has conducted monitoring of the U.S. coastline since 1984. Data from this database (see the

website http://state-of-coast.noaa.gov/bulletins/html/

ccom_05/ccom.html) indicate that levels of pollutants

are generally decreasing along the southern California coast (Catalina Island to San Luis Obispo). Areas

of 50 percent or more occurrences of “high” concentrations of particular contaminants are all located

south of Point Dume. A site is said to have a high

level of any particular contaminant if it fell within

the top 15 percent of all levels for all sites. The monitored points north of Point Dume include Point Santa

Barbara, Santa Cruz Island, Point Conception and San

Luis Obispo; none of these sites exhibited high levels

of any contaminant.

yy y

Parameter (Units) Characteristics

Temperature (°C) Ocean surface temperatures minimums of 12-13 °C in April and maximums

of 15-19 °C in July-October

Salinity (o/oo) Typically 33.2-34.3 o/oo (parts per thousand)

Dissolved oxygen (DO)

(mg/L or ml/L)

Maximum values of 5-6 ml/l at the surface, decreasing with depth; nearshore

values at 200 m depth about 2 ml/l; at depths below 350 m, values as low as 1

ml/l; upwelling can brings oxygen-poor water to the nearshore surface waters,

especially in May-July

pH (unitless) pH values range from about 7.8 to 8.1. pH increases with increased CO2

consumption, via photosynthetic activity, and with increasing salinity; pH

decreases slightly with increasing depth and decreasing temperature.

Nutrients (μg-atoms/l) Nutrients limiting primary production include nitrogen, phosphorus, and

silicon (nitrogen more than phosphorus); micronutrients include iron (Fe),

manganese (Mn), Zn, Cu, cobalt (Co), molybdenum (Mo), vanadium (V),

vitamin B12, thiamin and biotin. Concentrations in the water column show

depletion near the surface, increasing with depth.

Turbidity (mg/L) Suspended sediment concentrations average near 1 mg/L, but can range from

0.93 – 1.5 mg/L in the nearshore, surface waters (BLM, 1978). Higher levels

are found near the bottom sediments (mean of 0.4 mg/L and a range of 0.1 to

1.4 mg/L) while lower levels are found in the offshore regions (mean of 0.15

mg/L and a range of 0.07 – 0.32 mg/L). Periods of highest turbidity

correspond to periods of highest upwelling, highest primary production and

river runoff. Turbidity controls the depth of the euphotic zone, has

applications for (absorbed) pollutant transport and is of aesthetic concern.

Organics materials (μg/l) Naturally-occurring organic materials include a wide variety of molecules

ranging from hydrocarbons to biogenic-based substances. They may enter the

marine environment via natural processes or from anthropogenic sources.

Table 4.5-3. Key water quality parameters, typical units of measure and characteristics.
4-59

Description of the Affected Environment: Water Quality

The Southern California Bight Pilot Project

(SCBPP), a collaboration of 12 government organizations, conducted a 261-site comprehensive regional

monitoring survey in 1994. The primary objective was

to assess the spatial extent and magnitude of ecological disturbances on the mainland continental shelf of

the SCB and to describe relative conditions among

different regions of the Bight (Southern California

Coastal Water Research Project (SCCWRP), 1998).

The survey found water quality to be good

throughout the SCB. Almost all of the surface waters

were fully saturated with oxygen, and more than 99

percent of the SCB met California Ocean Plan waterquality objectives for dissolved oxygen and water clarity. Areas of reduced water clarity through the Bight

were mostly located in shallow water and probably

resulted from the natural resuspension of bottom sediments.

Trace metals, especially from anthropogenic

sources, are of concern throughout the Southern California Bight. Table 4.5-5 shows some values collected

during the 1976-1978 BLM-sponsored baseline studies. Inner shelves and basins are those associated either with the mainland or islands as opposed to those

located south of the Channel Islands towards and including Tanner and Cortez Banks.

Publicly-owned Treatment Works. There are six

POTWs that discharge treated effluent to the Channel (table 4.5-6). They are all small dischargers (less

than 25 million gallons/day) whose effluents are at a

mixed primary/secondary level of treatment (SCCWRP,

1996). Although secondary treatment of municipal

sewage removes at least 85 percent of the organic

material and suspended solids in wastewater, only onethird of the nitrogen and phosphorus is eliminated

(National Research Council (NRC), 1993; 2000). Generally, eutrification, or the over-abundant presence of

nutrients, is not generally a problem in the openocean, high energy environment that characterizes the

coastline of the study area. However, there are advanced treatment technologies that can remove up to

97 and 99 percent of nitrogen and phosphorus, respectively. There are very few other point sources of pollution along the shorelines of the Channel with few

industrially-based outfalls. Several power plants

spaced along the Santa Barbara, Ventura and northern Los Angeles County coastlines do discharge heated

water, and some chlorine is used to prevent fouling of

heat exchangers; however, effects from these effluents

are limited spatially.

Storm drains. Storm-water runoff is the largest

source of unregulated pollution to the waterways and

coastal areas of the United States (CCC, 2000). Because runoff is an untreated pollution source, it has

the potential to be a source of increased health risks

to swimmers near storm drains, higher concentrations

of metals in harbor and ocean sediments and increases

in toxicity to aquatic life. However, storm drain-associated pollution would be confined to the near-coastal

vicinity since, even during high runoff periods, the

volume would not be enough to carry pollutants very

far offshore.

The two major rivers, the Santa Clara and

Ventura, are both in Ventura County and drain largely

agricultural lands, although the urban areas of Ojai,

Ventura, Oxnard/Port Hueneme and Camarillo contribute pollutants via storm drains and other nonpoint

source runoff. Also, the plumes do cross the Channel

and can reach as far as the Northern Channel Islands

National Marine Sanctuary waters (Hickey and

Kaschel, unpubl.). However, as discussed above, most

of this untreated runoff occurs only during the rainy

season.

Past and Present OCS Oil and Gas Activities.

OCS oil and gas activities began off southern California in the late 1960’s (Galloway, 1997). Section 3 provides information on current offshore infrastructure

and levels and types of activities. Several reviews have

been made of the possible cumulative impacts of these

activities on physical, biological, and socioeconomic

resources in the region (Van Horn et al., 1988;

Bornholdt and Lear, 1995, 1997; MMS, 1996.

During the period of the 1950’s and 1960’s, regulation of discharges was less stringent that those of

Table 4.5-4. Dischargers in San Luis Obisbo county, the level of treatment and flow. g p y

Discharger Receiving water Treatment

Level

Flow (mgd)

City of Lompoc Santa Ynez River Secondary 3.72

San Luis Obispo San Luis Obispo Creek Tertiary 4.53

Pismo Beach Pacific Ocean Secondary 1.11

Avila Beach San Luis Obispo Creek Secondary 0.025

Tosco refinery Pacific Ocean Secondary 0.435

Source: Mike Higgins, Central Coast Regional Water Quality Control Board (pers. comm, 2001)
4-60

Delineation Drilling Activities Offshore Santa Barbara County

today. No records of what and how much was discharged exists from that period. In addition, six platforms and several piers, which support oil wells in

the Santa Barbara Channel, in State waters have been

decommissioned. Data from these platforms and piers

is similarly nonexistent (pers. comm., Michael Higgins,

Central Coast Water Resources Control Board, December, 2000). Of a total of 42 leases in State waters,

there are currently 18 producing leases, including five

offshore Ventura County and two offshore Santa Barbara County (California State Lands Commission

(CSLC), 2000).

The major discharges from oil and gas activities

have been described above and in table 4.5-1 along

with the 17 other potential oil and gas-related effluents. Each of the facilities that could discharge these

effluents are regulated by NPDES permits issued by

EPA. For facilities (including nonoil and gas) onshore

and in State waters, the local Water Resources Control Board has been delegated by EPA to oversee compliance with NPDES permits.

Oil and gas activities in the Channel currently

consist of 16 oil and gas platforms: 15 in Federal waters and one in State waters (for purposes of this discussion, the three oil and gas platforms west of Point

Conception – Harvest, Hidalgo and Hermosa – are

considered to be in the western Santa Barbara Channel). Only the facilities located in Federal waters discharge any effluents; no discharges are allowed from

facilities located in State waters. While all platforms

have the potential to discharge drilling muds and cuttings, only Exxon’s Platform Heritage is conducting a

drilling program at present, although Exxon is using

a both water- and oil-based drilling muds for these

extended-reach wells. Since oil-based muds cannot

be discharged, the amount of water-based muds being discharged for these wells is probably less than

for the other occasional wells that have been drilled

at the other platforms during the past 6 to 8 years.

Ten of the 16 platforms discharge produced water,

while all the platforms discharge deck drainage,

treated sewage, well completion and workover fluids,

and other effluents (table 4.5-1). The five most-common discharges, described in more detail below, contribute the most pollution and undergo the most treatment but may not comprise the most volume (this

could come from noncontact cooling water or firewater overpressure, both of which are sea water with no

treatment).

Drilling Fluids. Water-based drilling fluids (also

known as drilling muds), which are the only type permitted for discharge, is a fresh or sea water slurry of

clay (attapulgite or bentonite and sometimes others)

or natural organic polymer, barium or iron sulfate,

lignosulfonate, lignite and sodium hydroxide, plus

several minor additives (NRC, 1983). Oil-based drilling fluids may contain up to 10 percent mineral oil, as

well as water, and similar additives. Drilling muds

are not treated. If they become contaminated with a

material that exceeds oil and grease or toxicity limitations, they can be reinjected downhole or retained

and shipped to shore for disposal.

There is no evidence that past routine discharges

from offshore oil and gas facilities have no more than

temporarily degraded the water quality. While they

probably contributed to the overall pollutant load,

these discharges have been shown to dilute to below

detection fairly rapidly. For example Ayers et al.

(1980a) found that suspended solids concentrations

from discharged muds and cuttings reached background concentration at distances of 0.3 to 0.6 km

(9,600 to 19,200 ft) while Ayers et al. (1980b) found

g

Metal Average (ppm)

Inner Shelves

Average (ppm)

Inner Basins

Range (ppm)

All Sampled Areas

Barium 835 686 43 – 1899

Cadmium 0.57 0.93 0.2 – 5.5

Chromium 56 119 12 – 370

Lead 17 25 4.2 – 69

Zinc 54 101 12 – 227

Source: BLM, 1978.

Table 4.5-5. Selected trace metals found in sediments in the Southern California Bight.
4-61

Description of the Affected Environment: Water Quality

that suspended solids and particular trace metals

reached background levels in 0.5 to 1.0 km (16,000 to

32,000 ft). Houghton et al. (1980) found dilution rates

of 10,000 to 1 with 100 m (320 ft) of the discharge

point. Ray and Meek (1980), in a study in the high

energy environment of the Tanner Banks, offshore

California, found that suspended solids and trace

metals concentrations approached background levels

at a distance of 0.2 km (6,400 ft) from the exploratory

drilling rig. For all of these studies, once the discharge

ceased, parameters for water quality returned to normal. In addition, Jenkins et al. (1988) found that

barium levels resulting from drilling muds discharges

from an exploratory well reached background within

1,500 meters (4,800 ft) and ,more recently, tracers of

barium that was associated with drilling mud discharges from development wells offshore Point Conception, California, were detectable up to 6.8 km

(21,760 ft) from the discharging platforms.

Produced water. Produced water contains a suite

of components, including metals and dissolved hydrocarbons, that must be reduced as much as possible in

the effluent before it is discharged into the sea. These

components include, water-soluble organics such as

light aromatics (benzene, toluene and xylene); a variety of other aromatic and aliphatic compounds; and

metals such as barium (Ba), chromium (Cr), cadmium

(Cd), copper (Cu), zinc (Zn), mercury (Hg), lead (Pb),

silver (Ag), and nickel (Ni) (Unpubl. data, EPA, Region 9). Treatment of produced water is accomplished

by various mechanical (such as heat, corrugated plates,

and electrostatic) and chemical means. All facilities

that discharge produced water have a sampling point

installed in the pipe that discharges to the ocean where

samples for chemical and toxicity analyses are collected. This is the point where both the operator and

government inspectors can collect samples to ensure

that the produce water stream is meeting the limits

for the NPDES permit in effect at that facility (see

above regulatory setting discussion).

MMS has compiled an Excel spreadsheet for produced water discharges from 1988 to present (Panzer,

unpubl.). The data are based on the Discharge Monitoring Reports (DMRs) that each operator’s NPDES

permit require them to submit to the EPA. The

spreadsheet also has data from compliance sampling

conducted by EPA and MMS since 1990. Records of

discharges prior to 1988 are spotty at best and, in most

cases, include only a few records from a few platforms.

The data since 1988 generally indicate that operators

have met the terms of the permits (Panzer, 1999). Few

exceedances have been reported or detected by compliance monitoring. Operators are required, by the

terms of their permits, to report exceedences within

24 hours of the event. If this is not done, the operators are subject to penalties.

Produced water studies have shown dilutions of

up to 1500 to 1, which is similar to that cited in modTable 4.5-6. Publicly-owned treatment works that discharge into the Southern California Bight

(within the study area).

)

POTW Name Location Level of Treatment Volume Discharging 

(mgd) 

Goleta Santa Barbara 

Channel Primary/Secondary 5.2 

Santa Barbara Santa Barbara 

Channel Secondary 8.1 

Montecito Santa Barbara 

Channel Secondary 1.1 

Summerland Santa Barbara 

Channel Tertiary 0.17 

Carpinteria Santa Barbara 

Channel Secondary 1.5 

Oxnard Santa Barbara 

Channel Secondary 19.5 

Hyperion Treatment Plant Los Angeles Advanced Primary/ 

Secondary* 202/145 

Joint Water Pollution Control 

Plant (Los Angeles County) Los Angeles Advanced Primary/ Secondary* 144/188 

Terminal Island Los Angeles Secondary 16.9 

Catalina Island (Avalon) Los Angeles Secondary 0.67 

San Clemente Island Los Angeles Secondary 0.028 

Source: SCCWRP (1996; 1997) 
4-62

Delineation Drilling Activities Offshore Santa Barbara County

els developed to calculate dilution for the purpose of

determining compliance with NPDES permits (EPA,

2000a). Osenberg et al. (1992) studied a produced

water outfall offshore Carpinteria, California. This

outfall, located in shallow water (about 10 to 12 m (32

to 40 ft water depth)) in an open-coast environment,

was shutoff in 1986. In general the researchers found

that outplanted mussel performance (as measured by

shell growth) increased with distance from the outfall. However, the last two stations were 100 m and

1,000 m (320 and 3,200 ft, respectively) from the outfall. The researchers note that there was still some

detectable affect in mussel performance at 1,000 m

(3,200 ft) however, due to the lack of a station between 100 and 1,000 m, (320 to 3,200 ft) and their

inability to detect the physical signal of produced water past 100 m, they were unable to draw any firm

conclusions. Similarly, there was no evidence on the

competency of red abalone larvae settling past 500 m

(1,600 feet) from the outfall (Raimondi and Schmitt,

1992). The series of studies, cited above, resulted from

a study site in shallow water. No studies on produced

water discharges from OCS oil and gas facilities have

been conducted in deeper water. More detailed information on this effluent can be found in section

5.3.4.2(1).

Treated sewage. Sewage, treated with chlorine

to kill fecal coliform bacteria, is discharged from all

platforms. Generally, the sewage and the “gray” water from showers, sinks and the galley is co-mingled

after the sewage is treated and both are discharged

via the same outfall. Volumes discharged are calculated by assuming a factor of about 35 gallons per person per day aboard a platform or drilling vessel. Manning ranges from three to over 100 persons depending on the size of the facility and the amount of activity (for example, whether drilling is occurring).

Deck drainage. Deck drains capture various fluids and other materials that are spilled or washed

onto the decks of the platforms. All platforms have

4” (minimum required height) kick plates which prevent such spills from entering the sea. Deck drains

are generally plumbed to a settling tank where oily

liquids are skimmed off and the water treated with

the produced water stream. On some facilities, deck

drains are commingled with the produced oil and

treated, discharged, and regulated with the produced

water.

Well treatment and completion fluids. These materials can be discharged when existing production

wells need down-hole work, such as pump replacement

or any of a variety of well production enhancement

efforts. Any fluids emanating from these process can

be discharged provided they do not exceed oil and

grease limits or cause a sheen or other visible pollution on the sea surface. Most often, operators combine any fluids from the wells with the produced water stream (pers. comm., David Panzer, MMS); the

commingled stream then becomes subject to permit

limitations for the produced water effluent.

The various other effluents that can come from

facilities operating in the OCS are all subject to limitations but little treatment (table 4.5-1).

Natural seeps. Natural oil and gas seeps contribute significant amounts of hydrocarbon to the

marine environment. Most known seeps occur on the

mainland shelf, although others have been reported

around the Channel islands and offshore banks and

ridges (MMS, 1996). The four main seepage zones on

the mainland shelf are at Point Conception, Coal Oil

Point, Santa Barbara/Rincon in the Santa Barbara

channel and in the Santa Monica Bay (Anderson et

al., 1993). One of the world’s largest natural oil and

gas seeps lies offshore Goleta, just west of Santa Barbara. This seep was partially tented in the early 1980’s

by Arco, the owner at the time of the State leases on

which the seeps exist. Estimates of the amount of oil

an gas collected by the tents in the mid-1990’s were

150 bbl of oil and 230 MMSCF of gas per day (MMS,

1996). These and other seeps, occurring in the SCB,

contribute locally elevated hydrocarbons to the water

column and can form substantial slicks on the sea

surface.

The fate of pollutants discharged into the waters of this subregion can be many. For example, onshore-based pollutants from POTWs, storm drains and

other nonpoint sources can be taken-up by intertidal

animals, such as mussels or other bivalves. However,

mussels have been shown to be able to depurate their

body burdens when exposed to clean water after an

episode of pollution exposure (Neff, 1987; 1997).

Mussels are harvested from some offshore platforms

in the Santa Barbara Channel. These are collected by

scraping from the platform legs and taken to fresh

sea water for depuration and sold to local restaurants,

as well as to overseas markets.

Overall, water quality in the Santa Barbara

Channel area is relatively good. This is due to the

lack of major point- or nonpoint pollution sources such

as major sewage outfalls, urban-associated storm

drains, and major river outflow. Although river plumes

do impinge on the Santa Barbara Channel during periods of high outflow, the pollution associated with this

phenomenon becomes well-diluted as it spread across

the Channel. Additionally, pollution indicators, such

as beach closings, that show potential, coastally dependent pollution are somewhat contrasted with mussel watch data showing little land-based pollution problems.

High molecular weight petroleum aromatic hydrocarbons (PAHs) are one example of an anthropogenic-based pollutant. Offshore waters of the Southern California Bight receive this pollutant in the form

of soot from various combustion sources. Soot-asso-
4-63

Description of the Affected Environment: Water Quality

ciated PAHs are delivered to the Bight primarily in

aerial fallout, treated domestic waste discharges and

urban runoff. Petroleum aromatic hydrocarbons associated with soot are tightly bound to the particles

and are not readily bioavailable to marine organisms.

These compounds are not accumulated efficiently from

the food and are biodegraded rapidly in the tissues of

most marine animals; therefore, they do not

biomagnify in marine food webs and do not pose a potential hazard to fish that consume biofouling organisms from submerged platform structures.

Another example of a sink, in which pollutants

may bioaccumulate or biomagnify, is Santa Monica

Bay. Years of disposal of DDT, primarily via a sewage

outfall, and other chlorinated hydrocarbons resulted

in contamination of the sediments. Bottom-feeding

fish, such as white croaker, became contaminated,

resulting in public notices advising against eating

these and other fish caught in the Santa Monica Bay

area. Similarly, sewage sludge was discharged via an

outfall in the same area. This discharge ceased in the

mid-1980’s but the problem remained in terms of contamination of fish and other organisms that inhabit

the sea floor.

Effects on water quality from oil spills, can range

from a few days, to several weeks or months, depending on the size of the spill type of oil. Effects on the

water column could occur in the top 10 to 20 m (32 to

64 ft) of the water column, depending on sea state

and the type of oil. Specifically, the effects could include turbidity, biological and chemical oxygen demand

and release of hydrocarbons, such as BETX (benzene,

ethylbenzene, toluene and xylene) and naphthalene.

The slick would be affected by several factors including, wind and wave action, dissolution and volatilization losses. The dissolved components (BETX and

others) make up about 20 to 50 percent of crude oils

and would be subject to dispersion, dilution and volatilization, as well as to degradation via photolysis and

microbial processes. The majority of these low molecular weight aromatic compounds will be lost to volatilization within 24 to 48 hours (Jordan and Payne,

1980). Clean-up actions would also contribute to the

minimization of impacts to water quality.

4.6 BIOLOGICAL RESOURCES

4.6.1 ROCKY AND SANDY BEACH

HABITATS

Rocky beach habitat in this section refers to

the rocky tidepool habitat and its resident algal and

invertebrate communities. Sandy beach habitat refers to the habitat and the communities found on

the surface and inhabiting the sand. Birds, mammals and fishes present or visiting these habitats are

discussed in those specific sections in the EIS.

The Coastal Act of 1976 regulates development

in the coastal zone that includes sandy and rocky

beach habitats. Sandy and rocky beach habitats are

protected through local, State and Federal regulations and programs. County Local Coastal Plans

provide specific protection for sensitive habitats in

their County, limiting development activities that

impact these areas. The California Department of

Fish and Game manages marine resources in the intertidal zone, including commercial species such as

abalone. The U.S. Fish and Wildlife Service is the

Trustee for the resources under OPA 90 and would

be responsible for evaluating potential impacts in the

event of an oil spill, along with the California Department of Fish and Game. MMS protects rocky

and sandy beaches from oil and gas activities through

lease stipulations, regulations, inspection procedures

and mitigation measures designed to prevent oil from

reaching and impacting the shoreline, and to minimize beach impacts during pipeline installation.

REGIONAL SETTING

Approximately half of the shoreline from Point

Conception north along the coastline of California is

rocky, forming either broad benches or cliffs (Woodward and Clyde, 1982; Dugan et al., 1998, unpublished). Boulder and cobble beaches are patchily distributed within this same area (Dames and Moore,

1983; Woodward and Clyde, 1982). Within sandy

beach areas between Point Conception and the Santa

Ynez River, dune-backed and bluff-backed beaches

are evenly represented (Dugan et al, 1998, unpublished). North of Point Conception, where strong

and constant wave action prevails, sandy beaches are

found in the lee of each point due to depositional

patterns (NOAA, 1998, unpublished). Along the central coast, rocky shorelines form high cliffs and steep

rocky benches.

South of Point Conception, over three-fourths

of the shoreline is sandy (Dugan et. al., 1998, unpublished). Wave exposure changes dramatically

south of Point Conception with wave heights roughly

half the size of those found to the north, primarily