TABLE OF CONTENTS

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1. INTRODUCTION AND SUMMARY

1.1 Introduction 1-1

1.2 Nitrate Compliance Program 1-1

1.3 Report Purposes and Goals 1-2

1.4 Organization of the Report 1-2

1.5 Summary of Findings and Conclusions 1-4

1.6 Summary of Proposed Plan 1-6

2. HEALTH EFFECTS AND REGULATION OF NITRATE

2.1 Health Effects of Excessive Nitrate 2-1

Methemoglobinemia (Blue-baby Syndrome) 2-2

Other Health Concerns Associated with Nitrate 2-2

2.2 Drinking Water Standards and Sources of Nitrate 2-4

Environmental Protection Agency Regulations 2-4

Major Sources of Nitrate in Groundwater 2-5

Non-Agricultural Nitrate Sources 2-6

Agricultural Sources of Nitrate 2-6

2.3 Regulation of Groundwater Nitrate in California 2-7

Porter-Cologne Water Quality Control Act (State Water Code) 2-7

State Water Resources Control Board and Regional Boards 2-7

Programs of the State Board 2-8

Central Valley Regional Water Quality Control Board 2-9

Water Quality 2-9

2.4 Use of Onsite Systems in California 2-10

Report of the State Technical Advisory Committee for Onsite Sewage Disposal Systems 2-10

Use of Onsite Systems in Butte County 2-11

2.5 Regulatory Actions in the Chico Urban Area 2-12

Nitrate Action Plan 2-12

Regional Board Prohibition Order 2-13

Recent Requirements of the Regional Board 2-13

Potential Enforcement Actions by the Regional Board 2-14

2.6 Role of County Service Area 114 2-17

Scope of Authorized Activities 2-17

Summary of Activities and Expenditures 2-18

3. SCOPE AND RESULTS OF THE TECHNICAL PROGRAM

3.1 Overview 3-1

3.2 Previous Studies 3-2

3.3 Recent Technical Program Studies 3-4

Hantzsche Equation 3-4

Technical Team 3-6

Scope of Technical Studies 3-6

Nitrate Characterization 3-8

d¹⁵N Isotopic Analysis 3-9

Evaluation of Potential Nitrate Sources 3-12

3.4 Conclusions as to Nitrate Loading from Onsite Systems 3-14

3.5 Refinement of the Hantzsche Equation 3-15

4. NITRATE ELIMINATION, REDUCTION, & ONSITE COMPLIANCE

4.1 Technical Basis for Implementation Plan 4-1

Objective: Sustainable Nitrate Loading Within the Chico Urban Area 4-2

Cost-Effective, Targeted Solutions 4-2

4.2 Elimination: Sewering Higher Densities & Designated Areas 4-3

Nitrate Loading 4-3

Prevalence of System Failures and/or Operational Problems 4-5

Poor Soils and Separation from Groundwater 4-5

Average Age of Existing Onsite Systems 4-5

Rational Boundaries and Equitable Cost Distribution 4-10

4.3 Application of Sewer Criteria to Chico Urban Area 4-10

4.4 Reduction: Retrofit Technologies for Onsite Systems 4-12

Recirculating Trickling Filters 4-12

4.5 Non-Residential Systems 4-13

4.6 Compliance: Meeting the Maximum Contaminant Level 4-13

Resolution 68-16 (Non-Degradation) 4-13

Water Code §13280 (Prohibiting Disposal Systems) 4-14

Water Code §13282 (Individual Disposal Systems) 4-14

Water Code §13283 Alternatives to Disposal 4-14

Region 5 Basin Plan Wastewater Reuse Policy 4-15

Alternatives and Interim Measures for Difficult Sewer Connections 4-15

5. SEWER FEASIBILITY, COST & FINANCING

5.1 Summary of Sewer Feasibility Analysis 5-1

Objectives of the Sewer Feasibility Study 5-1

Engineering Team and Scope of Work 5-2

Current Sewer Treatment and Disposal in the Chico Urban Area 5-3

Alternative Methods of Sewer Collection 5-4

5.2 Estimated Cost of the Collection System 5-4

5.3 Treatment Plant Issues 5-6

Operation of the Water Pollution Control Plant Under Waste Discharge Requirements 5-6

Cease and Desist Order for Discharge Violations 5-6

Expansion of Plant Capacity and Projected Connection Fees 5-7

5.4 Summary and Allocation of Costs 5-8

5.5 Financing of Sewer Improvements 5-8

State Revolving Fund Loan Program 5-8

Tax Increment Financing (Greater Chico Urban Area Redevelopment Project) 5-9

Assessment Installments (City of Chico) 5-11

Community Development Block Grant Program 5-11

Small Communities Supplemental Assistance Program 5-12

Development of Local Area Revolving Fund 5-12

Assessment Bonds 5-12

5.6 Creation of Financing Program 5-13

6. OVERSIGHT MONITORING PROGRAM FOR ON-SITE SYSTEMS

6.1 Summary of Septic Tank Regulatory Oversight 6-1

6.2 Need for Oversight 6-2

Development of an Oversight Monitoring Program 6-2

City of Chico Involvement with Onsite Systems 6-3

6.3 Description of the Oversight Monitoring Program. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4

6.4 Design and Operating Criteria for Onsite Systems 6-6

Design Standards 6-6

Operating Standards 6-6

6.5 Survey of Existing Systems 6-6

6.6 Training and Certification of Onsite Personnel 6-7

6.7 Waste Discharge Requirements 6-7

6.8 Supersedence of the Nitrate Action Plan. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-7

7. LOCAL GOVERNMENT JURISDICTION, DEVELOPMENT & RELATED ISSUES

7.1 County and City Jurisdiction and Cooperation 7-1

Existing County and City Agreements Relevant to Nitrate Compliance 7-2

Opportunities for Cooperation Between City and County 7-2

7.2 Annexation Policy 7-3

City of Chico Policy Requiring Annexation as a Condition of Sewer Service 7-3

Annexation Law and the Local Agency Formation Commission 7-3

7.3 Proposed Memorandum of Understanding Between County and City 7-5

Discussion of Issues and Draft Provisions 7-5

7.4 Wastewater Disposal Requirements for New Development 7-6

Minimum Lot Sizes and Density Limits for New Development 7-6

8. ENVIRONMENTAL REVIEW AND COMPLIANCE

8.1 Requirements of the California Environmental Quality Act 8-1

8.2 Previous Environmental Documents 8-2

EIR for Adoption of the Master Sanitary Sewer and Storm Drainage Master Plans 8-2

EIR for the Greater Chico Urban Area Redevelopment Project 8-3

City of Chico General Plan EIR 8-3

EIR for Expansion of Water Pollution Control Plant 8-4

8.3 CEQA Compliance Alternatives 8-4

8.4 Use of the Project EIR 8-6

8.5 Supplemental Environmental Documents and Processes 8-7

9. IMPLEMENTATION COMPONENTS AND SCHEDULE

9.1 Review of Recommended Implementation Components 9-1

Provision of Sewer Service to Designated Areas 9-1

Determination and Implementation of Financing Plan Components 9-2

Implementation of County Service Area 114 for Management of Onsite Systems 9-2

Adoption of Memorandum of Understanding with City of Chico 9-2

9.2 Public Information and Outreach 9-2

Outreach - Butte County Division of Environmental Health . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3

Citizen's Nitrate Advisory Committee 9-4

9.3 Agency Consideration, Public Hearings, and Action 9-5

Workshop Session and Formal Actions of the Regional Board 9-5

Formal Actions 9-5

APPENDICES

Appendix

A. Glossary

B. Summary of Key State and Regional Board Statutes and Resolutions

C. RWQCB Order No. 90-126 - Revision of the Water Quality Control Plan, Sacramento River Basin 5A, By the Addition of prohibition of Waste Discharge from Individual Disposal Systems in the Chico Urban Area, Butte County

D. RWQCB Resolution No. 95-024 - Deferral of Enforcement Action Regarding Board Order No. 90-12 (Basin Plan Amendment) for Chico Urban Area. Butte County

E. SWRCB Resolution No. 92-49 - Policies and Procedures for Investigation and Cleanup and Abatement of Discharges under Water Code Section 13304

F. SWRCB Resolution No. 88-63 - Adoption of Policy Entitled " Sources of Drinking Water"

G. The Hantzsche/Finnemore Mass Balance Equation

H. Members of the Citizens Nitrate Advisory Committee

I. CEQA Guidelines - Article 11. Types of EIRs

J. SWRCB Resolution No. 68-16 - Statement of Policy with Respect to Maintaining High Quality of Waters in California

K. Amendment to the Policy regarding the assessment of parcels within CSA 114

L. List of References

M. Assessment Bonds

N. Nitrate Action Plan

O. Proposed Septic Tank Installation Standards for the Chico Urban Area

P. Map of CSA 114

Q. Summary of CSA 114 Expenditures 1989-1999

R. Letter from the Regional Board regarding the Oversight Monitoring Program

S. Public Information Materials - Frequently Asked Questions - Minutes from the October 28, 1999 Public Meeting

TABLES

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Table 2-1: Summary of Responsiveness to RWQCB Requirements 2-16

Table 2-2: CSA 114 Revenues and Expenses 1989-1999 2-20

Table 2-3: CSA 114, Description and Amounts of Expenditures per Category, 1989-1999 2-21

Table 4-1: Septic System Failures and Operational Problems in the Chico Urban Area , 1991-1995 4-7

Table 5-1: Sewer Feasibility Study Areas 5-3

Table 5-2: Construction Cost Summary for Extension of the Existing Gravity Collection System 5-5

Table 9-1: Preliminary Schedule for Adoption of the Implementation Plan and Approval by Regional Board 9-7

FIGURES

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Figure 3-1: Nitrate Plumes as Identified by DWR, 1984 3-3

Figure 3-2: General Direction of Groundwater Flow 3-8

Figure 3-4: Nitrate in the Intermediate Aquifer 3-10

Figure 3-3: Nitrate in the Shallow Aquifer 3-11

Figure 3-5: Map to Accompany Historical Land Use Report 3-13

Figure 4-1: Nitrate Loading from Onsite Systems 4-4

Figure 4-2: Areas Exceeding Sustainable Density 4-6

Figure 4-3: Relationship of Rate of Repair to Age of Septic System 4-7

Figure 4-4: Septic System Failures and Operational Problems 4-8

Figure 4-5: Areas of Poor Soils and/or Perched Winter Groundwater Conditions 4-9

Figure 4-6 Application of Sewer Criteria to Chico Urban Area 4-11

Figure 5-1: Greater Chico Urban Area Redevelopment Project Area 5-10