Добавил:
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз: Предмет: Файл:

Biosolids Engineering - Michael McFarland

.pdf
Скачиваний:
50
Добавлен:
10.08.2013
Размер:
10.44 Mб
Скачать

Biosolids Management Practices and Regulatory Requirements

 

 

 

Management Practices and Regulatory Requirements

1.41

TABLE 1.17 Recordkeeping and Reporting Requirements for

 

 

 

 

Land-Applied Biosolids*

 

 

 

 

 

 

 

 

 

 

 

 

 

Person responsible

Records that

 

 

for recordkeeping

Type of

Records that

must be

 

 

 

biosolid

must be kept

Preparer

Applier

reported

 

 

 

 

 

 

 

EQ† biosolids

Pollutant concentrations

X

 

 

 

X

 

Pathogens-reduction

 

 

 

 

 

 

certification and description

X

 

 

 

X

 

Vector attraction reduction

 

 

 

 

 

 

certification and description

X

 

 

 

X

 

 

 

 

 

 

 

PC† biosolids

Pollutant concentrations

X

 

 

 

X

 

Management practice

 

 

 

 

 

 

certification and description

 

X

 

 

 

Site restriction certification

 

 

 

 

 

 

and description (Class B

 

 

 

 

 

 

requirements)

 

X

 

 

 

Pathogen-reduction

 

 

 

 

 

 

certification and description

X

 

 

 

X

 

Vector attraction reduction

 

 

 

 

 

 

certification and description

X

X‡

 

X

 

 

 

 

 

 

 

CPLR† biosolids

Pollutant concentrations

X

 

 

 

X

 

Management practice

 

 

 

 

 

 

certification and description

 

X

 

 

 

Site restriction certification

 

 

 

 

 

 

and description (Class B

 

 

 

 

 

 

biosolids)

 

X

 

 

 

Pathogen-reduction

 

 

 

 

 

 

certification and description

X

 

 

 

X

 

Vector attraction reduction

 

 

 

 

 

 

certification and description

X

X‡

 

X

 

 

 

 

 

 

 

APLR† biosolids

Pollutant concentrations

X

 

 

 

X

 

Management practice

 

 

 

 

 

 

certification and description

X

 

 

 

X

 

Pathogen-reduction

 

 

 

 

 

 

certification and description

X

 

 

 

X

 

Vector attraction reduction

 

 

 

 

 

 

and description

X

 

 

 

X

 

AWSAR§ for biosolids

X

 

 

 

X

 

 

 

 

 

 

 

*Adapted from ref. [24].

†EQ, exceptional-quality; PC, pollutant concentration; CPLR, cumulative pollutant loading rate; APLR, annual pollutant loading rate.

‡The preparer certifies and describes vector attraction reduction methods other than injection and incorporation of biosolids into the soil. These methods must be certified by the land applier.

§Annual whole sludge application rate (dmt/hectare-year or U.S. ton/acre-year).

Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved.

Any use is subject to the Terms of Use as given at the website.

Biosolids Management Practices and Regulatory Requirements

1.42Chapter One

TABLE 1.18 Physical and Chemical Characteristics of Domestic Septage Relative to Sewage Sludge*

 

 

Concentration

 

 

(mg/kg, dry-weight basis)

 

 

 

 

Parameter

Domestic septage

Sewage sludge

 

 

 

Arsenic

4

10

Cadmium

3

7

Copper

140

740

Lead

35

130

Mercury

0.15

5

Nickel

15

43

Selenium

2

5

Zinc

290

1200

Nitrogen as N

2%

2–7%

Phosphorus as P

1%

1–3%

pH

 

6–7

5–8

Grease

 

6–12%

5–10%

Biochemical oxygen demand (BOD5)†

 

6480 mg/liter

>2000 mg/liter

Total solids

3.4%

3–35%

 

 

 

 

*Adapted from ref. [15].

†BOD5 is highly variable in sewage sludge.

The specific definition of domestic septage in the 40 CFR Part 503 rule does not include many of the other materials that are often called septage by industry. For example, commercial and industrial septage are not considered domestic septage. The factor that differentiates commercial and industrial septage from domestic septage is not the type of establishment generating the waste; rather, it is the type of waste being produced. For example, even though restaurant grease trap wastes are not considered domestic septage, the sanitation waste residues and residues from food and normal dish cleaning from a restaurant are considered domestic septage. Similarly, sanitation waste residues from a gasoline station are domestic septage, whereas wastes containing petroleum are classified as nondomestic septage. Finally, it is critical to note that any mixing of domestic and nondomestic septage (e.g., the collection of both domestic and nondomestic septage in a pumper truck or holding tank) causes the entire batch of septage to be considered nondomestic septage. Nondomestic septage is not regulated under the 40 CFR Part 503 rule [20,26].

1.2.10.1 Use and disposal of domestic septage. In addition to being suitable for discharge in municipal wastewater or septage-only treatment facilities, domestic septage may be applied to nonpublic contact sites, applied to public contact sites, or disposed in a biosolids-only monofill or municipal landfill. If domestic septage is discharged into

Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved.

Any use is subject to the Terms of Use as given at the website.

Biosolids Management Practices and Regulatory Requirements

Management Practices and Regulatory Requirements

1.43

a treatment facility that receives only domestic septage, the treated septage can be applied to either public or nonpublic contact sites. Public contact sites are defined as lands with a high potential for contact by the public, such as public parks, ball fields, cemeteries, plant nurseries, turf farms, and golf courses. If treated septage is to be applied to a public contact site, the septage is considered a sewage sludge and must meet the more extensive requirements of the 40 CFR Part 503 rule, including (1) general requirements, (2) pollutant limits,

(3) management practices, (4) operational standards covering pathogen-reduction criteria and vector attraction reduction requirements, (5) monitoring requirements, (6) recordkeeping, and (7) reporting requirements. If the treated septage is to be applied to a nonpublic contact site (e.g., agricultural land, forest, or reclamation site), the requirements governing land application are less burdensome (see Sec. 1.2.10.2).

If domestic septage is discharged into a sanitary sewer or directly into a POTW that also receives municipal wastewater, the person discharging the domestic septage must follow the rules of that POTW. The residual solids from the treatment of the sewage sludge and domestic septage would be covered by the specific provisions of 40 CFR Part 503 rule that apply to the biosolids use or disposal practice being followed. Alternatively, if domestic septage is placed in a sewage sludge-only landfill (called surface disposal in the 40 CFR Part 503 rule) or incinerated in a sewage sludge-only incinerator, its disposal is covered by the requirements in the 40 CFR Part 503 rule for those disposal practices.

Finally, if domestic septage is placed in a municipal solid waste landfill, its disposal is covered by the rules of the disposal facility, which, in turn, must comply with the requirements of 40 CFR Part 258 that specifies the criteria for the disposal of nonhazardous wastes [10,11].

1.2.10.2 Land application of domestic septage. To meet the federal requirements for land application of domestic septage to nonpublic contact sites, the land applier must ensure that he or she has only domestic septage. Only when domestic septage is applied to nonpublic contact sites are the less burdensome land-application requirements specified within the 40 CFR Part 503 rule applicable. Persons who apply domestic septage to nonpublic contact sites (agricultural land, forests, and reclamation sites) must comply with (1) limits on volumetric application rates based on the nitrogen demand of the crop and restrictions on crop harvesting, animal grazing, and site access and (2) provisions for control of pathogens and vector attraction reduction [20,26].

Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved.

Any use is subject to the Terms of Use as given at the website.

Biosolids Management Practices and Regulatory Requirements

1.44Chapter One

Domestic septage applied to nonpublic contact sites is not required to meet the specific ceiling, cumulative, or pollution concentration limits that are applicable to land-applied sewage sludge. When a domestic septage land applier chooses not to meet these limits, the annual domestic septage application rate (gallons per acre-year) depends on the amount of nitrogen required by the planned crop and the yield. The maximum annual domestic septage application rate may be estimated by Eq. (1.4). The factor 0.0026 in Eq. (1.3) was obtained by assuming that (1) the nitrogen content in septage is completely mineralized over a 3-year period, (2) domestic septage is approximately 2.5 percent solids, and (3) the nitrogen content in septage is approximately 350 mg/kg (dry-weight basis) [15,20,26].

gallons

 

 

Annual application rate

 

acre yr

 

 

lb N

 

lb of nitrogen required by the crop

 

acre yr

(1.4)

 

0.0026

 

Although Eq. (1.4) was included in the 40 CFR Part 503 rule to facilitate the land application of a “typical” domestic septage, in some cases, the assumptions that are inherent in Eq. (1.4) do not apply. For example, in cases where the domestic septage has been dewatered prior to land application (e.g., which typically occurs during storage of domestic septage), the solids content will be significantly greater than the 2.5 percent assumed in developing Eq. (1.4). Under these circumstances, it is recommended that the dewatered septage be treated by the land applier as a POTW sewage sludge [15,20,26]. This approach would necessitate the measurement of the actual nitrogen content of the septage prior to land application. In other cases, the domestic septage may have a nitrogen content far in excess of the assumed valued of 350 mg/kg (e.g., septage discharged from a type III marine sanitation device). Although the 40 CFR Part 503 rules does not require it, good practice would dictate that the volume of domestic septage that is applied to land should be reduced from the value calculated using Eq. (1.4) if its nitrogen content is significantly greater than 350 mg/kg. In any event, under no circumstances can domestic septage be applied to land at rates in excess of those calculated by Eq. (1.4). Examples of domestic septage application rates for various crops using Eq. (1.4) are provided in Table 1.19.

1.2.10.3 Domestic septage pathogen-reduction requirements. Domestic septage that is to be applied to land on a nonpublic contact site must

Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved.

Any use is subject to the Terms of Use as given at the website.

 

Biosolids Management Practices and Regulatory Requirements

 

 

Management Practices and Regulatory Requirements

1.45

TABLE 1.19 Typical Domestic Septage Rates*

 

 

 

 

 

 

 

 

Yield

Nitrogen requirement

Application rate†

 

Crop

(bushel/acre-year)

(lb N/acre-year)

(gal/acre-year)

 

 

 

 

 

 

Corn

100

100

38,500

 

Oats

90

60

23,000

 

Barley

70

60

23,000

 

Grass/hay

4 tons/acre

200

77,000

 

Wheat

70

105

40,400

 

Soybeans

40

30

11,500

 

Cotton

1.5 bale/acre

90

35,000

 

 

 

 

 

 

*Adapted from refs. [15,20,26]. †Calculated using Eq. (1.4).

be managed so that pathogens are reduced. The 40 CFR Part 503 rule offers domestic septage land appliers two alternatives to meet this requirement. The first alternative uses crop, grazing, and site restrictions exclusively with no chemical treatment, while the second alternative requires raising the pH of the septage to 12 for 30 minutes through chemical addition.

For septage land appliers who choose the second alternative to meet pathogen-reduction criteria, the chemicals most commonly used to raise the pH of domestic septage are hydrated lime (Ca(OH)2) and quicklime (CaO). Regardless of the chemical chosen, at a minimum, two separate representative samples of the chemically treated domestic septage must be taken 30 minutes apart to verify that the pH remains at a value of 12 or higher for that time period.

The lime can be added to the septage in dry form or as a slurry. In most cases, 20 to 40 lb of lime must be added per 1000 gallons of domestic septage. The exact amount will vary depending on the septage characteristics. If, after adding lime, the septage does not maintain a pH of at least 12, more lime must be added so that the septage will remain at a pH of 12 or higher for 30 minutes. The pH of the domestic septage sample can be evaluated using either a pH meter or pH-sensitive colored paper.

Although there is the added expense of chemical addition, the second alternative for meeting the pathogen-reduction requirement has an advantage in that domestic septage subject to alkaline treatment need only meet crop restriction requirements (i.e., there are neither grazing nor site restrictions). The requirements for both pathogenreduction alternatives are summarized in Table 1.20.

It should be noted that some of the pathogen-reduction requirements outlined in Table 1.20 describe approaches that are unique for certain types of crops. The principal crop characteristic that affects the choice of pathogen-reduction approach is whether the edible part of the crop will touch the soil-septage mixture. Table 1.21 provides a list

Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved.

Any use is subject to the Terms of Use as given at the website.

Biosolids Management Practices and Regulatory Requirements

1.46Chapter One

TABLE 1.20 Land Application of Domestic Septage: Pathogen-Reduction

Requirements*

Alternative I: Septage That Is Land Applied without Chemical Treatment

Crop restrictions

Food crops with harvested parts that touch the septage-soil mixture and are totally above ground shall not be harvested for 14 months after application of domestic septage.

Food crops with harvested parts below the soil surface of the land shall not be harvested for 38 months after application of domestic septage.

Animal feed, fiber, and those food crops that do not touch the soil surface shall not be harvested for 30 days after application of the domestic septage.

Turf grown on land where domestic septage is applied shall not be harvested for 1 year after application of the domestic septage when the harvested turf is placed on either a lawn or land with a high potential for public exposure, unless otherwise specified by the permitting authority.

Grazing restrictions

Animals shall not be allowed to graze on the land for at least 30 days after application of domestic septage.

Site restrictions

Public access to land with a low potential for public exposure shall be restricted for at least 30 days after application of domestic septage. Examples of restricted access include remoteness of site, posting with no trespassing signs, and/or fencing.

Alternative II: Chemically Treated Septage That Is Land Applied†

Crop restrictions

Food crops with harvested parts that touch the septage-soil mixture and are totally above ground shall not be harvested for 14 months after application of domestic septage.

Food crops with harvested parts below the soil surface of the land shall not be harvested for 20 months after application of domestic septage when the domestic septage remains on the land surface for 4 months or longer prior to incorporation into the soil.

Food crops with harvested parts below the surface of the land shall not be harvested for 38 months after application of domestic septage when the domestic septage remains on the land surface for less than 4 months prior to incorporation into the soil.

Animal feed, fiber, and those food crops that do not touch the soil surface shall not be harvested for at least 30 days after application of the domestic septage.

Turf grown on land where domestic septage is applied shall not be harvested for 1 year after application of the domestic septage when the harvested turf is placed on either a lawn or land with a high potential for public exposure, unless otherwise specified by the permitting authority.

Grazing restrictions

None

Site restrictions

None

*Adapted from refs. [20,26,31].

†Domestic septage has had its pH raised to 12 or higher by addition of alkaline material and, without adding more alkaline materials, the domestic septage remains at a pH of 12 or higher for at least 30 minutes prior to land application.

Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved.

Any use is subject to the Terms of Use as given at the website.

Biosolids Management Practices and Regulatory Requirements

 

 

Management Practices and Regulatory Requirements

1.47

TABLE 1.21 Crops Affected by Domestic Septage Pathogen

 

Requirements*

 

 

 

 

 

 

 

 

 

Crops that do

Crops that do

Crops that are

 

not touch the soil

touch the soil

below ground

 

 

 

 

 

 

Peaches

Melons

Potatoes

 

Apples

Eggplant

Yams

 

Corn

Squash

Sweet potatoes

 

Wheat

Tomatoes

Rutabaga

 

Oats

Cucumbers

Peanuts

 

Barley

Celery

Onions

 

Oranges

Strawberries

Leaks

 

Grapefruit

Cabbage

Radishes

 

Cotton

Lettuce

Turnips

 

Soybeans

Hay

Beets

 

 

 

 

 

 

*Adapted from ref. [15].

of various crops and distinguishes whether or not the edible parts are likely to touch the soil-septage mixture.

1.2.10.4 Vector attraction reduction approaches. If the septage pathogen-reduction requirements are met using alternative I, one of two approaches must be employed to meet vector attraction reduction. The first approach is to use subsurface injection of the septage, whereas the other approach requires incorporation of the septage into the soil (i.e., plowing or disking) within 6 hours of land application.

If the septage pathogen-reduction requirements are met using alternative II (i.e., alkaline treatment of septage), vector attraction reduction requirements are assumed to be met. A summary of the vector attraction reduction alternatives for land application of domestic septage is provided in Table 1.22.

If the pathogen and vector attraction reduction requirement for domestic septage is met using alkali addition, each container, i.e., truck

TABLE 1.22 Domestic Septage Vector Attraction Reduction Approaches*

Approach I Domestic septage shall be injected below the surface of the land, and no significant amount of the domestic septage shall be present on the land surface within 1 hour after the domestic septage has been injected.

Approach II Domestic septage applied to the land surface shall be incorporated into the soil surface plow layer within 6 hours after application.

Approach III The pH of domestic septage shall be raised to 12 or higher by addition of alkaline material and, without the addition of more alkaline material, shall remain at 12 or higher for 30 minutes.

*Adapted from refs. [26,31].

Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved.

Any use is subject to the Terms of Use as given at the website.

Biosolids Management Practices and Regulatory Requirements

1.48Chapter One

Figure 1.11 Typical pathogen-reduction certification for land appliers of domestic septage.

load, of domestic septage must be tested for pH before it is applied to agricultural land, forest, or a reclamation site. Domestic septage that is not treated by pH adjustment does not need to be monitored.

The land applier of domestic septage must sign a certification form that states that the pathogen and vector attraction reduction requirements of the 40 CFR Part 503 rule have been met. The septage land applier must retain this certification for at least 5 years. Figure 1.11 illustrates a typical pathogen and vector attraction reduction certification form for land-applied domestic septage.

1.2.10.5 Management practices. There are no specific federal management practice requirements for land appliers of domestic septage to nonpublic contact sites in the 40 CFR Part 503 rule. On the other hand, many states do require that specific management practices be

Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved.

Any use is subject to the Terms of Use as given at the website.

Biosolids Management Practices and Regulatory Requirements

Management Practices and Regulatory Requirements

1.49

followed. State or local management requirements may include the specification of minimum distances between domestic septage landapplication sites and drinking water wells and/or surface water. Good practice also would suggest a caution against applying domestic septage to flooded, frozen, or snow-covered land that could result in contaminated runoff.

1.2.10.6 Recordkeeping. For land application of domestic septage to nonpublic contact sites, the records that must be kept for at least 5 years are summarized in Table 1.23.

1.2.11 Liability issues and enforcement oversight

The 40 CFR Part 503 rule is self-implementing, which means that its provisions must be followed regardless of whether or not a permit has been issued. The 40 CFR Part 503 rule includes enforcement measures regarding the proper testing and application of biosolids [24]. Landowners and leaseholders who use biosolids beneficially as a fertilizer substitute or soil conditioner in accordance with the 40 CFR Part 503 rule specifications are protected from liability under CERCLA (i.e., Superfund) as well as any enforcement action from the USEPA. Where the federal requirements are not followed, appliers of biosolids are vulnerable to USEPA enforcement actions or citizen-ini- tiated law suits and can be required to remediate any problems for which they are found liable.

The USEPA oversight of biosolid land-application practices includes a program for administering permits and for monitoring, reporting, and inspecting [30]. Preparers and land appliers of biosolids are

TABLE 1.23 Records That Must Be Kept by Septage Haulers/Land Appliers*

1.The location of the site on which domestic septage is applied.

2.The number of acres in the application site.

3.The date and time domestic septage is applied.

4.The nitrogen requirement of the crop or vegetation grown on the site in a 365-day period.

5.The rate in gallons per 365-day period at which domestic septage is applied.

6.Certification that pathogen and vector attraction reduction requirements have been met.

7.Descriptions of how pathogen and vector attraction reduction requirements have been met.

*Adapted from refs. [20,26,31].

Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved.

Any use is subject to the Terms of Use as given at the website.

Biosolids Management Practices and Regulatory Requirements

1.50Chapter One

required to maintain appropriate records, and Class I biosolids management facilities must self-report on their activities during the preceding calendar year by February 19. Annual compliance reports must include information on biosolids quality and, in the case of CPLR biosolids, a field-by-field analysis of the site activity including information on management practices and the cumulative application of regulated pollutants.

To ensure compliance with the 40 CFR Part 503 rule, the USEPA conducts routine sampling and inspection of regulated facilities. If discrepancies are identified, enforcement actions can be taken, including fines, injunctive relief, and, in cases of deliberate violation of the federal requirements, criminal imprisonment [24].

1.3 Surface Disposal

In the 40 CFR Part 503 rule (Subpart C), surface disposal is defined as an activity in which biosolids are placed on land for final disposal. However, if the disposal activity involves the discharge of biosolids that meet pollutant concentrations (e.g., cumulative pollutant loading rates or annual pollutant loading rates) as well as ceiling limits, and the biosolids are land applied at agronomic rates, it is considered land application, not surface disposal. Although some surface-disposal sites may be used for beneficial purposes (e.g., nutrient management), the placement of biosolids on land for treatment or storage is not considered surface disposal. Finally, codisposal of biosolids in a municipal solid waste landfill is not considered surface disposal under the 40 CFR Part 503 rule. The practice of discharging biosolids to a municipal landfill is regulated by 40 CFR Part 258 [11,19,30,32]. The biosolids surface-disposal facilities regulated under the 40 CFR Part 503 rule include the following: (1) monofills, (2) surface impoundments and lagoons, (3) waste piles, (4) dedicated disposal sites, and (5) dedicated beneficial-use sites. Each of these facilities is described briefly in the following sections. Readers interested in obtaining further detail on the design of surface-disposal facilities are directed to the following references [14,32].

Monofills are defined as landfills in which only biosolids are disposed. The two basic methods of monofilling biosolids include (1) trenching and (2) area filling. In the trenching method, biosolids are disposed entirely below the ground surface. Since subsurface excavation is required, trenching is only feasible in situations where the groundwater and/or bedrock is located at a sufficient depth to permit biosolids land disposal while still maintaining an adequate soil buffer between the bottom of the biosolids deposits and the groundwater surface or bedrock [14].

Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved.

Any use is subject to the Terms of Use as given at the website.