The Class V Underground Injection Control Study Volume 19

0,98

MB

Heat Pump and Air Conditioning Return Flow Wells

62

stron

5005

ID

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

2001

rok

Table of Contents

1. Summary 1

2. Introduction 3

3. Prevalence of Wells 4

4. Wastewater Characteristics and Injection Practices 8

4.1 Injectate Characteristics . 8

4.2 Well Characteristics . 10

4.2.1 Well Types 10

4.2.2 Well Design . 12

4.3 Operational Practices 12

5. Potential and Documented Damage to USDWs . 14

5.1 Potential Injectate Impacts to USDWs . 14

5.1.1 Thermal Alteration 14

5.1.2 Mineral Precipitation Due to Changes in Water Pressure or Oxygen Levels . 15

5.1.3 Chemical Contamination . 15

5.1.4 Water Quantity . 17

5.2 Observed Impacts . 17

6. Best Management Practices . 18

6.1 Well Design and Siting 19

6.1.1 Alternative Technological Design 19

6.1.2 Pre-Construction Practices 19

6.1.3 Siting Issues . 20

6.1.4 Design Features 20

6.2 Heat Pump Injection Well Construction . 21

6.3 Heat Pump Injection Well Operation, Maintenance, and Monitoring . 22

7. Current Regulatory Requirements 24

7.1 Federal Programs . 24

7.2 State and Local Programs 25

Attachment A: State and Local Program Descriptions 27

References 58