City of Morro Bay and Cayucos Sanitary District OFFSHORE MONITORING AND REPORTING PROGRAM 2014 ANNUAL REPORT Estero Bay Marine Research Pt.Specialists Arguello Pt. Buchon 3140 Telegraph Rd., Suite A Ventura, California 93003 Report to the City of Morro Bay and Cayucos Sanitary District 955 Shasta Avenue Morro Bay, California 93442 (805) 772-6272 OFFSHORE MONITORING AND REPORTING PROGRAM 2014 ANNUAL REPORT Prepared by Bonnie Luke and Douglas A. Coats (Marine Research Specialists) and Bruce Keogh (City of Morro Bay Wastewater Treatment Plant Division Manager) Submitted by Marine Research Specialists 3140 Telegraph Rd., Suite A Ventura, California 93003 Telephone: (805) 644-1180 Telefax: (805) 289-3935 E-mail: [email protected] March 2015 TABLE OF CONTENTS Page LIST OF FIGURES ......................................................................................................................................... v LIST OF TABLES ......................................................................................................................................... vii LIST OF ACRONYMS .................................................................................................................................... ix EXECUTIVE SUMMARY .................................................................................................... ES-1 1.0 INTRODUCTION .............................................................................................................. 1-1 1.1 REPORT ORGANIZATION ............................................................................................ 1-1 2.0 TREATMENT PLANT PERFORMANCE ..................................................................... 2-1 2.1 WASTEWATER TREATMENT PLANT ........................................................................... 2-2 2.1.1 Operations ................................................................................................................ 2-3 2.1.2 Plant History ............................................................................................................ 2-6 2.1.3 Regulatory Setting ................................................................................................. 2-10 2.1.4 Description of the Treatment and Outfall System .............................................. 2-12 2.1.5 Pollution Prevention Program ............................................................................. 2-14 Industrial Waste Survey ..................................................................................... 2-14 Public Outreach .................................................................................................. 2-15 Source Identification .......................................................................................... 2-17 2.2 WASTEWATER CHARACTERIZATION ....................................................................... 2-18 2.2.1 Flow Rate ............................................................................................................... 2-19 2.2.2 Suspended Solids, Turbidity, and Settleable Solids ........................................... 2-20 2.2.3 Biochemical Oxygen Demand ............................................................................... 2-23 2.2.4 Oil and Grease ....................................................................................................... 2-24 2.2.5 pH ........................................................................................................................... 2-25 2.2.6 Temperature .......................................................................................................... 2-25 2.2.7 Ammonia ................................................................................................................ 2-26 2.2.8 Residual Chlorine .................................................................................................. 2-26 2.2.9 Coliform Bacteria .................................................................................................. 2-27 2.2.10 Toxicity ................................................................................................................... 2-28 2.2.11 Nutrients ................................................................................................................. 2-29 2.2.12 Chemical Compounds ........................................................................................... 2-30 Trace Metals ....................................................................................................... 2-32 Arsenic and Selenium ......................................................................................... 2-32 Radionuclides ..................................................................................................... 2-32 Phenolic Compounds .......................................................................................... 2-33 Cyanide ............................................................................................................... 2-33 Dioxin ................................................................................................................. 2-33 2.3 BIOSOLIDS ................................................................................................................. 2-33 2.3.1 Solids Treatment Process ...................................................................................... 2-34 2.3.2 Chemical Compounds ........................................................................................... 2-35 i TABLE OF CONTENTS (Continued) Page 3.0 RECEIVING WATER QUALITY ................................................................................... 3-1 3.1 MONITORING PROGRAM ............................................................................................ 3-1 3.1.1 Objectives of Sampling ........................................................................................... 3-1 3.1.2 Scope of Monitoring ................................................................................................ 3-2 3.1.3 Sampling Station Design ......................................................................................... 3-4 3.1.4 Navigation ................................................................................................................ 3-7 3.1.5 Sampling Equipment and Methodology ................................................................ 3-8 Auxiliary Measurements ...................................................................................... 3-8 Instrumental Measurements .................................................................................. 3-8 3.2 PLUME DISPERSION .................................................................................................. 3-10 3.2.1 Zone of Initial Dilution.......................................................................................... 3-11 3.2.2 Critical Initial Dilution Ratio ............................................................................... 3-12 3.2.3 Regional Oceanographic Processes ...................................................................... 3-13 3.2.4 Ambient Seawater Properties ............................................................................... 3-16 3.3 COMPLIANCE EVALUATION ...................................................................................... 3-19 3.3.1 Screening for Applicability ................................................................................... 3-20 Measurement Location ....................................................................................... 3-20 Presence of Wastewater Constituents ................................................................. 3-21 Natural Variation ................................................................................................ 3-22 3.3.2 Numerical Limits ................................................................................................... 3-23 COP Objectives .................................................................................................. 3-23 Basin Plan Limits ............................................................................................... 3-24 3.3.3 Other Lines of Evidence ........................................................................................ 3-25 Mixing Performance ........................................................................................... 3-26 Effluent Quality .................................................................................................. 3-27 Entrainment Signature ........................................................................................ 3-28 3.3.4 Visual Observations .............................................................................................. 3-29 3.4 BENEFICIAL USE ....................................................................................................... 3-29 4.0 MARINE SEDIMENTS AND BENTHIC BIOTA .......................................................... 4-1 4.1 MONITORING PROGRAM ............................................................................................ 4-1 4.1.1 Scope of Monitoring ................................................................................................ 4-1 4.1.2 Sampling Station Design ......................................................................................... 4-3 4.1.3 Benthic Sample Collection and Processing ........................................................... 4-4 Equipment ...........................................................................................................