Developing Green Stormwater Design Solutions For UIC

Compliance

Presented by: Adam Zucker PE, CWRE

819 SE Morrison Street ● Suite 310 ● Portland, Oregon 97214 ● 503.274.2010 ● www.vigil-agrimis.com

Underground Injection Control

- A federal program under the Safe Drinking Water Act that regulates the injection of fluids into the ground

Purpose:

To protect groundwater from contamination

What do we mean by UIC?

UIC 101 – History Of Injection Wells Early Injection- Injection of water to extract salts was documented in China around 300 A.D. and in France in the 9th Century

UIC 101 – History Of Injection Wells 1930s- Oil and Gas Extraction

1940s- Oil refineries begin to inject wastes into ground

1950s- Chemical companies begin injecting industrial waste into deep wells

UIC 101 – History Of Injection Wells 1960s- Deep well injection causes earthquakes in Colorado- 1st documented case of drinking water contamination

1970s- Wastes spilling out of an abandon oil well traced to an injection well used by a pulp mill some distance away

- Congress passes the Safe Drinking Water Act - 1974

UIC 101 – Regulations

1980s- Federal UIC regulations are passed ◦ Define 5 classes of injection wells

- Washington Department of Ecology (DOE) andOregon Department of Environmental

Quality (DEQ)delegated the authority to administer

the UIC program - 1984

UIC 101 – Regulations

State UIC enforcement responsibilities - Primacy

UIC 101 – Classes of Injection Wells Class I : Deep injection wells for municipalities and industries (549 wells)

Class II : Oil and Gas production (143,951 wells)

Class III : Mineral Extraction (18,505 wells)

Class IV : Shallow storage of hazardous and radioactive wastes. Banned in 1984 (32 sites)

Class V : All other injection wells (400,000 to 650,000 wells)

well inventory numbers based on

EPA data

Several subcategories for Class V wells

Septic Systems Groundwater RechargeHeating and CoolingGeothermal Stormwater Disposal

UIC 101 – Class V Wells

Injection Well Sump Soakage TrenchFrench Drain Seepage PitDrainfieldSoakaway

UIC 101 – Class V Stormwater Wells

UIC 101 – Class V Stormwater Wells…but for this presentation we generally mean

Drywells

UIC 101 – Drywells

UIC 101 – Wells

UIC 101 – Back to the Regulations- In 1999 Federal regulations for Class V UICs are revised/clarified -States begin to revise their rules and adopt the following general requirements:

◦ Must be registered◦ Have no impact on water Quality

◦ Meet all other state and federal requirements

◦ Stormwater only; runoff minimized◦ No other disposal options

◦ Isolated from Drinking water sources◦ No soil or groundwater contamination◦ Not deeper than 100’ AND adequate

groundwater separation ◦ Pretreatment and spill prevention

Generally requirement:

Groundwater Separation Requirements

The bottom of the drywell should be at least 10 feet above the groundwater table.

USGS Groundwater Study - 2008

How to deal with the groundwater vertical separation requirements?

- Connect into a piped stormwater conveyance system

- Modify the existing drywell

- Surface Infiltration – LID and Green Streets

Sorting out UIC compliance

Connecting to an Existing Storm System

Connecting to an Existing Storm System

Connecting to an Existing Storm System

Utility Conflicts

Utility Conflicts

Utility Conflicts

Utility Conflicts

Retrofitting Existing Drywells

Retrofitting Existing Drywells

Retrofitting Existing Drywells

Retrofitting Existing Drywells

Retrofitting Existing Drywells

Retrofitting Existing Drywells

Retrofitting Existing Drywells

Connecting to an Existing Storm System

Retrofitting Existing Drywells

Retrofitting Existing Drywells

Determining hydraulic capacity of drywell retrofit

- Drainage basin area

- Design storm

- Subsurface soil conditions

- Capacity tests

Retrofitting Existing Drywells

Retrofitting Existing Drywells

Surface Infiltration - Green Street / LID

Surface Infiltration - Green Street / LID

Surface Infiltration - Green Street / LID

Surface Infiltration - Green Street / LID

Surface Infiltration - Green Street / LID

Surface Infiltration - Green Street / LID

Surface Infiltration - Green Street / LID

Surface Infiltration - Green Street / LID

Surface Infiltration - Green Street / LID

-No longer an overflow to storm sewer system

-Space constraints; limited right-of-way

-Capturing all the runoff at intersections

- Facility Longevity

- Be conservative and provide redundancy

Surface Infiltration - Green Street / LIDDesign Challenges and Concerns

Questions

819 SE Morrison Street ● Suite 310 ● Portland, Oregon 97214 ● 503.274.2010 ● www.vigil-agrimis.com