EPA Erosion and Sediment Controls

What pipe allowed to be installed in ROWs?

HP and RCP

What is the female end of an HP called?

The bell end

What pipe is not allowed to be installed in ROWs?

HDPE

What material is used for bedding under both RCP and HP pipes?

Screening

How much screening is placed below the pipe for both RCP and HP?

6 inches

For RCP, to what point is the screening brought up around the pipe?

To the spring line

For HP pipe, how far above the pipe is the screening brought up?

12 inches above the pipe

What materials make up a normal silt fence?

Metal stakes and black fabric

What materials make up reinforced silt fence?

Normal + Wire backing

What materials make up super silt fence?

Normal + Chain link backing

Inlet protection is typically used for what type of projects?

Undeveloped projects

What materials are used to build inlet protection?

T-posts, hardware cloth, and gravel

Where is the gravel placed when constructing inlet protection?

Around the catch basin

What erosion control device is used for storm drains?

Silt Sack

What is the purpose of a rock outlet?

To allow water to flow through while collecting some sediment and taking the load off the silt fence

Where are rock outlets typically located?

Periodically along a silt fence

What is another name for a wet pond?

A retention pond

Does a wet pond hold water permanently or temporarily?

Permanently

Where does the inlet of a wet pond discharge water first?

Into the forebay

What does water pass through after the forebay before reaching the MTA?

It filters through rocks

What structure in the MTA allows water to exit once it reaches a certain level?

The riser

Where does the water go after entering the riser?

Out through the outlet pipe

Why are rocks placed around the inlet and outlet pipes in a wet pond?

To provide additional filtering and to prevent runoff from mixing directly with the water coming from the pipe

What is another name for a dry pond?

A detention pond

Does a dry pond hold water permanently or temporarily?

Temporarily

What materials can be used to cover a sand filter?

Sand, sod, or rocks

What feature helps identify a sand filter installation?

Capped PVC pipes sticking out of the ground

How does a sand filter function to clean stormwater?

Water seeps through the sand and top layer, then into perforated PVC pipes underground that collect and route it to an outlet pipe

What are bio-retention ponds, and how do they differ from sand filters?

They function similarly to sand filters but are covered with various plants instead of just sand or rock

What are two key features that identify a temporary sediment basin?

Baffles and a skimmer

What is the purpose of a temporary sediment basin?

To temporarily collect and settle out sediment from stormwater runoff before it leaves a construction site

What are bonds in the context of construction or erosion control projects?

An insurance policy or financial guarantee held by the contractor's agreement

How does a bond work?

The contractor lists all tasks to be completed, each assigned a monetary value

What can be done if the contractor fails to complete or fix specific items?

The bond can be cashed out for the value of those incomplete or unsatisfactory items

For low impact development, what is the required total buffer distance between the silt fence and TB?

50 feet

In a low impact development buffer zone, how wide is the revegetated buffer directly behind the silt fence?

30 feet

In a low impact development buffer zone, how wide is the undisturbed buffer beyond the revegetated buffer?

20 feet

For high impact development, what is the required total buffer distance between the silt fence and TB?

100 feet

In a high impact development buffer zone, how wide is the revegetated buffer directly behind the silt fence?

50 feet

In a high impact development buffer zone, how wide is the undisturbed buffer beyond the revegetated buffer?

50 feet

What are the dimensions of the trench used to install a silt fence?

6 inches deep and 6 inches wide

Where is the backfill placed when installing a silt fence?

In front of the fabric in the trench

How far apart should the metal stakes be placed when installing a silt fence?

6 feet apart

What is the main goal of the erosion and sediment control?

To preserve topsoil and manage stormwater and sediment effectively

Why is it important to preserve topsoil in erosion and sediment control?

It maintains soil health and supports revegetation

How should stormwater be directed to help control erosion?

Toward vegetated areas for infiltration and filtering

Why is it important to control the flow rate and volume of stormwater?

To prevent erosion and reduce sediment transport

What are some key practices to minimize sediment trackout?

Stabilizing entrances/exits, cleaning tires, and maintaining gravel pads

How can soil compaction be minimized on construction sites?

By limiting equipment traffic and restoring compacted areas

What measures help minimize dust generation on a site?

Applying water or other dust suppressants, and stabilizing disturbed soil

Why must stockpiles be managed carefully in erosion control?

To prevent erosion and sediment runoff from stored materials

What should be done to protect storm drain inlets during construction?

Use inlet protection devices such as silt sacks, hardware cloth, or gravel barriers

Are ESCs typically temporary or permanent?

They are typically temporary but can be permanent in some cases

What is considered the first line of defense in erosion and sediment control?

Erosion control

What is considered the second line of defense in erosion and sediment control?

Sediment control

What are the two main types of erosion and sediment controls (ESCs)?

Structural and non-structural

What are structural ESCs?

Physical structures or devices such as sediment basins, silt fences, and inlet protection

What are non-structural ESCs?

Activities or methods such as preserving existing vegetation and maintaining buffer zones

What factors should be considered when selecting and designing ESCs?

Precipitation patterns, flow patterns, soil type, and particle sizes

Why should contingencies for major storms be included in ESC design?

To ensure controls remain effective during heavy rainfall or extreme weather events

Why might different phases of a project require different ESCs?

Because site conditions, construction activities, and drainage patterns change over time

When should erosion and sediment controls (ESCs) be installed?

During the pre-construction phase

What must be installed before starting any land-disturbing activities?

Downgradient sediment controls and any controls needed for the next disturbing activities

What are examples of downgradient sediment controls?

Natural buffers, perimeter controls, exit point controls, and storm drain inlet protection

What type of work is considered routine maintenance in erosion and sediment control?

Minor repairs or general upkeep

What is considered a corrective action?

A significant repair or repeated maintenance issue that requires more than routine attention

When is corrective action triggered?

When the same routine maintenance is required three or more times at the same location

When can corrective action be exempted or not considered necessary?

If it is documented in the report explaining why it shouldn't be corrective action, usually due to an unforeseen incident

Where should the SWPPP be kept?

On site and easily accessible

What information should the SWPPP include about construction activities?

A descriptive and projected schedule for construction phasing, temporary and final stabilization, and ESC removal

What should the site map in the SWPPP show?

The locations of phased activities, stockpiles, and ESCs

What details about ESCs must be included in the SWPPP?

Descriptions, design specifications, routine maintenance details, and the implementation schedule

What procedures must the SWPPP include regarding ESCs?

Inspection, maintenance, and corrective action procedures

What should be maintained as a key non-structural ESC?

Natural buffers

Where should stormwater be directed as part of non-structural ESC practices?

Toward vegetated areas

What type of disturbances should be minimized to reduce erosion risk?

Disturbances on steep slopes

Why should topsoil be preserved in non-structural ESC practices?

To maintain soil health and promote revegetation

How can soil compaction be minimized on a construction site?

By limiting heavy equipment traffic and avoiding unnecessary disturbance

What measures should be taken to minimize dust on-site?

Apply water or dust suppressants and stabilize disturbed soil

What is a natural buffer?

An area of undisturbed natural cover

What is the purpose of providing and maintaining a natural buffer?

To protect water quality and reduce sediment and pollutant runoff

Can a natural buffer replace ESCs?

No, a natural buffer is not a replacement for ESCs

According to the CGP, when do special buffer requirements apply?

When a site is within 50 feet of a receiving water

What is Option 1 for meeting the CGP buffer requirement?

Maintain a natural 50-foot buffer

What is Option 2 for meeting the CGP buffer requirement?

Maintain a natural buffer of less than 50 feet supplemented with additional ESCs

What is Option 3 for meeting the CGP buffer requirement?

If a natural buffer isn't possible, implement ESCs that achieve an equivalent sediment load reduction to a 50-foot natural buffer

How should stormwater be directed to help control erosion and improve water quality?

Toward vegetated areas to maximize filtration and infiltration

How does directing stormwater through vegetation help reduce sediment?

It filters and infiltrates runoff, reducing sediment transport

How should flow from the site perimeter be directed?

As non-erosive flow toward natural buffers

What is the exception to directing stormwater toward vegetated or natural buffer areas?

Sites with underlying geology or groundwater contamination concerns

What slope grade is considered steep and should be minimized for disturbance?

Slopes greater than 15%

When disturbance of steep slopes cannot be avoided, what must be done?

Implement appropriate erosion and sediment controls to manage runoff and prevent erosion

According to regulations, which sites must stabilize disturbed areas sooner—those with 5 or more acres of disturbance, or those with less?

Sites with 5 or more acres of disturbance

What type of ESCs are check dams, stockpile management, stabilized construction entrances, diversions, perimeter dikes/swales, and level spreaders examples of?

Structural erosion controls

What is the main purpose of structural erosion controls?

To slow, divert, or spread stormwater to reduce erosion and sediment transport

What type of ESCs are perimeter controls, sediment basins, storm drain inlet protection, pumped water filter bags, and turbidity curtains examples of?

Structural sediment controls

What is the main purpose of structural sediment controls?

To capture and settle out sediment from stormwater before it leaves the construction site

Where should perimeter controls be installed in relation to disturbed areas?

Downslope from disturbed areas