Table 1. Maximum Allowable Metal Concentrations in Sludge Amended Soils USEPA 503 Regulations (USEPA 1997)

ERDC TN-DOER-C12

February 2000

beneficial uses such as manufactured topsoil, engineered soil capping material, building blocks, or

flowable fill. The following discussion will explain how to approach the evaluation of specific

beneficial uses of dredged material.

ENGINEERED PRODUCTS

Manufactured Topsoil: To evaluate the potential for manufactured topsoil in a particular

location, local sources and types of cellulose and biosolids will need to be identified. Cellulose can

be in many forms, such as yard waste, sawdust, wastepaper, storm debris, shredded paper, etc.

Biosolids can be animal manures, such as dairy cow, beef cow, chicken, turkey, or swine manures,

and/or sewage sludge biosolids. The quality, quantity, and availability of these materials must be

determined. Potential markets for the soil products will need to be identified. Potential markets

could include, but not be limited to, landscaping, nurseries, bagged soil products, highway

construction rights-of-way, parks, ball fields, golf courses, etc. Characterization tests of the dredged

material should be conducted in accordance with Winfield and Lee (1999) and Lee (1999).

Screening tests of blends of the dredged material, cellulose, and biosolids should be conducted as

described in Sturgis and Lee (1999).

Results of the characterization and screening tests should be presented to local authorities for their

review, comment, and approval as a potential acceptable product. There are no universal soil

contaminant concentration standards that are acceptable in all situations. A number of states have

or are attempting to establish acceptable contaminant screening levels for soils used for residential

and industrial purposes. The basis for these screening levels varies from state to state. In some

cases, background concentrations of contaminants in local soils

Table 1

are considered, while other screening levels are related to risk

Maximum Allowable

assessments. In either case, local regulatory authorities will

Metal Concentrations in

decide the acceptability of manufactured soil products and their

Sludge Amended Soils

uses for residential, industrial, or any other purposes. The

USEPA 503 Regulations

USEPA has established maximum levels of metals in agricul-

(USEPA 1997)

tural soils receiving biosolids derived from sewage sludge

(Table 1, USEPA 1997). These soil concentrations have been

Concentration

derived from risk assessments of various soil to plant to animal

Metal

ppm

scenarios. It would appear that manufactured topsoil with metal

Arsenic

concentrations below those listed in Table 1 could be used for

Cadmium

Chromium

3,000

agriculture, or restoration of abandoned minelands, landfill cov-

Copper

1,500

ers, and Superfund sites that will be developed for wildlife

Lead

300

habitat. Coordination with local entities, such as municipal,

Mercury

Nickel

420

county, State, and Federal agencies, that have requirements for

2,800

Zinc

topsoil should be conducted to identify potential markets for

topsoil. A commercialization plan should be developed using

available resource materials. Participants in the development of the commercialization plan will

vary from location to location. Participants can be, but are not limited to, commercial entities

possessing patented technology (such as Recycled Soil Manufacturing Technology) or a properly

licensed commercial entity, sources of available cellulose and biosolids, and other interested entities.

The plan should then be submitted to the appropriate entity(ies) with authority over the dredged

material to be reclaimed.