Frequently Asked Questions

Structural Soil was developed by River Sand, Inc. for urban tree landscapes.  The design specifies the type of gravel, soil, and additives by type and quality for a tested, proven structural soil mix. 

It’s a sand or sand blend designed to fill the divots creating by golfers when the club removes a portion of the turf beneath the ball.  These holes often occur on the tee box or at certain areas within the fairway.  Divot Sand is a way that the holes can be repaired quickly by the golfer to level the hole back up and provide a way for the turf to grow back over rapidly.  Divot sand, also called divot mix, can be just sand or it can be blended with grass seed, fertilizer, peat or compost.  The sand can also be dyed green or selected as a natural tan color to blend in the rootzone better than white sand.  Divot mix is like your favorite recipe, and can be blended based on each golf courses needs and preferences.

Engineered soil is a soil designed and blended, or manufactured, for a specific purpose or with specific physical and chemical characteristics.  Often, the engineered soil is a blend to meet a texture including a target percentage of sand, silt, and clay particles including a percentage of organic matter within those components.  Engineered soils are typically used in stormwater applications such as bioretention areas and bioswales, but can include any type of topsoil for a project. 

Applications where engineered soils may be required include:

• Bioretention ponds, basins, and cells
• Rain Gardens
• Detention and retention ponds for stormwater
• Parking lot infiltration
• Pervious pavers and pervious pavement
• Vegetated roof systems or Green Roof Soil
• Upslope from channels, ditches, streams, and other water bodies
• Treating runoff from impervious surfaces such as roads, highways, parking lots, and other land disturbing activities
• Structural soil for planting near curbs, sidewalks, and roads
• Rootzone for athletic fields
• Topsoil for reclamation areas or landscaping

Engineered topsoil is a topsoil that is designed to meet a specification.  Typical blends of engineered topsoil have parameters for pH, organic matter content, soluble salt, texture, and nutrients. 

In the Atlanta and surrounding areas in Georgia, fill dirt is typically characterized by red clay.  It can be more or less sandy in texture but is often unscreened, meaning that it can contain rocks or other debris.  It is excavated from the ground and is great to use to build up areas to the desired grade.  Some fill dirt can be used as compatible fill for dams, foundations, and other functions. 

Fill dirt is commonly used as a construction material for grading on construction projects.  For landscaping, fill dirt is an excellent material to build up low areas, add to divert runoff, and backfill against basements or other structures.  Fill dirt is not the best option for planting grass in but as an economical fill material you may consider filling up areas with fill dirt which stays in place easier.  Then topping the fill dirt with 6 to 8 inches of topsoil before planting. 

Good planting mix contains a combination of sand, soil, and compost.  The quality of the ingredients are a key part of a quality landscaper’s planting mix.  The ratio at which each component is blended also is critical to retain moisture, provide nutrients, and drain well.  Planting mix refers to a soil, unlike potting soil, that is best used in your landscaping and gardening areas. 

Most granite sand is used for aggregate in ready-mix concrete.  There are many types of granite sand.  Most of it is washed and screened but contains a lot of fine particles that allow it to compact.  The shape is generally angular and flat shape that adds to its ability to compact.  It works well as a compactable base for pavers and pathways.  It also works great as a base for horse arenas.  However, it is often too fine and dusty to be used as a footing.

Hydraulic dredging is when sediment is pumped from a body of water to a processing area where materials are either discharged for disposal or processed for further use or disposal.  The slurry is typically a high percentage of water.  Hydraulic dredging can move gravel, sand, silt, clay, or sludge.