Standards for the Use or Disposal of Sewage Sludge

SUMMARY: Today's action amends the existing regulation regarding the

land application, surface disposal, and incineration of sewage sludge.

The amendments clarify existing regulatory requirements regarding

operational standards for pathogen and vector attraction reduction and

provide flexibility to the permitting authority and the regulated

community in complying with the minimum frequency of monitoring

requirements. The amendments also make the incineration subpart of the

regulation totally self-implementing by providing information on air

dispersion modelling, incinerator testing methods, and continuous

emission monitors to the sewage sludge incinerator owner-operator. It

also amends the existing General Pretreatment Regulation for Existing

and New Sources of Pollution by adding a concentration for total

chromium in land-applied sewage sludge to the list of pollutants that

are eligible for a removal credit issued by a wastewater treatment

works treating domestic sewage.

EFFECTIVE DATE: The final rule is effective September 3, 1999. For

purposes of judicial review, this final rule is promulgated as of 1 pm

eastern time on August 18, 1999 as provided in 40 CFR 23.7.

FOR FURTHER INFORMATION CONTACT: Alan B. Rubin, Ph.D., Senior

Scientist, Health and Ecological Criteria Division (4304), Office of

Science and Technology, U.S. Environmental Protection Agency, 401 M

Street, SW, Washington, DC 20460, telephone (202) 260-7589.

SUPPLEMENTARY INFORMATION:

I. Regulated Entities

II. Authority

III. Background

IV. Final Amendments to the Part 503 Land Application, Surface

Disposal, Pathogen, and Vector Attraction Reduction Requirements

A. Ceiling Concentration Limits--Land Application

B. Frequency of Monitoring

C. Certification Language

D. Time of Application

E. Definition of pH

F. Class B, Alternative 1--at the Time of Use or Disposal

G. Site Restriction for Grazing of Animals

H. Vector Attraction Reduction Equivalency

I. Vector Attraction Reduction at the Time of Use or Disposal

J. Time Period for Vector Attraction Reduction Option 10

K. Technical Corrections

1. Sections 503.16(a)(1) and 503.26(a)(1)--Frequency of

Monitoring

2. Section 503.17(b)(7)--Recordkeeping for Land Application of

Domestic Septage

3. Section 503.18--Reporting

4. Section 503.21(c)--Contaminate An Aquifer

5. Section 503.22(b)--General Requirements

6. Section 503.32(a)(3)--Pathogens

7. Appendix B to Part 503--Pathogen Treatment Processes

V. Final Amendments to the Part 503 Incineration Requirements

A. Compliance period

B. Site-Specific Exemption from Frequency of Monitoring,

Recordkeeping, and Reporting Requirements

C. Pollutant Limits for Arsenic, Cadmium, Chromium, Lead and

Nickel

D. Management Practices

E. Frequency of Monitoring

F. Recordkeeping

VI. Final Amendment to Part 403

VII. Regulatory Requirements

A. Executive Order 12866, Regulatory Planning and Review

B. Regulatory Flexibility Act

C. Congressional Review Act

D. Paperwork Reduction Act

E. Unfunded Mandate Reform Act

F. Executive Order 12875, Enhancing Intergovernmental

Partnerships

G. Executive Order 13084, Consultation and Coordintion With

Indian Tribal Governments

H. Executive Order 13045, Protection of Children from

Environmental Health Risks and Safety Risks

I. National Technology Transfer and Advancement Act

I. Regulated Entities

Entities potentially regulated by today's action are those that

prepare sewage sludge and use or dispose of the sewage sludge through

application to the land, placement on a surface disposal site,

placement in a municipal solid waste landfill unit, or firing in a

sewage sludge incinerator. Regulated categories and entities include:

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Category Examples of regulated entities

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State/Local/Tribal Gov............ Publicly-owned treatment works that

treat domestic sewage.

Federal Government................ Federally-owned treatment works that

treat domestic sewage.

Industry.......................... Privately-owned treatment works that

treat domestic sewage, and persons

who receive sewage sludge and

change the quality of the sewage

sludge before it is used or

disposed.

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The above list of regulated categories and entities is not intended

to be exhaustive, but rather provides a guide for readers regarding

entities likely to be regulated by this action. The list includes the

type of entities that EPA is now aware could potentially be regulated

by this action. Other types of entities not listed above also could be

regulated. To determine whether your facility is regulated by this

action, you should carefully examine the applicability section in

Sec. 503.1 (Purpose and Applicability) of part 503 of Title 40 of the

Code of Federal Regulations. If you have questions regarding the

applicability of this action to a particular entity, contact the

individual whose name is in the preceding FOR FURTHER INFORMATION

CONTACT section.

II. Authority

The amendments to part 503 are promulgated pursuant to the

authority of section 405 of the Clean Water Act (CWA), which requires

EPA to establish numerical limits and management practices that protect

public health and the environment from the reasonably anticipated

adverse effects of toxic pollutants in sewage sludge. Section 405(e)

prohibits any person from disposing of sewage sludge from a publicly

owned treatment works (POTWs) or any other treatment works treating

domestic sewage for any use or disposal for which regulations have been

established pursuant to subsection (d) of section 405 except in

compliance with such regulations.

The amendment to part 403 is promulgated under the authority of

sections 307 and 405 of the CWA. In section 307(b) of the CWA, Congress

directed EPA to establish categorical pretreatment standards for

industrial discharges of toxic pollutants to POTWs. Congress authorized

POTWs in defined circumstances to provide relief from categorical

pretreatment standards in the form of a removal credit to

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indirect dischargers. Section 307(b) authorizes a removal credit where,

among other things, grant of the removal credit does not prevent the

POTW from using or disposing of its sewage sludge in compliance with

section 405 of the CWA.

III. Background

A. Part 503 Amendments

On February 19, 1993, EPA promulgated, pursuant to section 405(d)

of the CWA, Standards for the Use or Disposal of Sewage Sludge (58 FR

9248). This regulation establishes the requirements that protect public

health and the environment when sewage sludge is: (1) Applied to the

land to either condition the soil or fertilize crops grown in the soil;

(2) placed on a surface disposal site; (3) placed in a municipal solid

waste landfill unit; or (4) fired in a sewage sludge incinerator. EPA

amended the part 503 sewage sludge regulation on February 25, 1994 (59

FR 9095) and again on October 25, 1995 (60 FR 54764) to address various

issues.

On October 25, 1995, EPA published a document in the Federal

Register proposing several technical changes to part 503 (60 FR 54771).

These changes were intended to address a number of issues identified

since promulgation of the regulation. The proposed changes clarify

certain requirements, provide additional flexibility to the regulated

community in complying with the part 503 requirements, and modify the

requirements for sewage sludge incinerators to make the requirements

self-implementing. Comments on the October 1995 proposal were

considered in developing the changes in today's final rule.

B. Part 403 Amendment

Industrial facilities that discharge specific pollutants to POTWs

for treatment must pretreat their effluent to meet categorical

pretreatment standards promulgated under section 307(b) of the CWA.

Section 307(b) also provides that where POTWs provide some or all of

the treatment of an industrial user's wastewater required to meet a

categorical pretreatment standard, POTWs may grant ``a removal credit''

to such an indirect discharger. The credit, in the form of a less

stringent categorical pretreatment standard, allows an increased

concentration of a pollutant in the discharge from the indirect

discharger to the POTW.

Section 307(b) of the CWA establishes three criteria that a POTW

has to meet to obtain authority to grant a removal credit to a

discharger of a toxic pollutant to the POTW: (1) The POTW removes all

or any part of the toxic pollutant, (2) the POTW's ultimate discharge

does not violate the effluent limitation or standard that would be

applicable to the toxic pollutant if it were discharged directly rather

than through a POTW, and (3) the discharge to the POTW does not prevent

sewage sludge use or disposal by the POTW in accordance with section

405 of the CWA. EPA promulgated removal credit regulations that are

codified at 40 CFR 403.7.

On February 19, 1993, EPA amended the part 403 General Pretreatment

Regulations to add a new Appendix G that includes two lists of

pollutants eligible for a removal credit with respect to the use or

disposal of sewage sludge if the other procedural and substantive

requirements of 40 CFR 403.7 are met. The first list (Appendix G--

Section I) includes, by sewage sludge use or disposal practice, the

pollutants regulated in EPA's Standards for the Use or Disposal of

Sewage Sludge (40 CFR part 503). The second list (Appendix G--Section

II) includes, by sewage sludge use or disposal practice, additional

pollutants eligible for a removal credit if the concentration of the

pollutant in sewage sludge does not exceed the prescribed

concentration. The pollutants in Appendix G--Section II are the

pollutants EPA evaluated and decided not to regulate during the

development of the part 503 regulation. See 58 FR 9381-9385, February

19, 1993.

The October 1995 proposal addressed the concentration for total

chromium for land-applied sewage sludge on the list of pollutants in

Appendix G--Section II of the part 403 regulations. EPA concluded after

reviewing comments on the proposed concentration to establish the

concentration at the value in today's final rule.

IV. Final Amendments to the Part 503 Land Application, Surface

Disposal, Pathogen, and Vector Attraction Reduction Requirements

A. Ceiling Concentration Limits--Land Application

In the October 25, 1995, document, EPA proposed to amend the

applicability section of the land application requirements to clarify

that the ceiling concentration limits (Table 1 of Sec. 503.13) apply to

all sewage sludge that is land-applied. Specifically, EPA proposed to

amend Sec. 503.10(b)(1), (c)(1), (d), (e), (f), and (g) to expressly

provide that the ceiling concentration limits have to be met in all

cases. All commenters on this proposed change concurred with the

change. Thus, today's action amends Sec. 503.10(b)(1), (c)(1), (d),

(e), (f), and (g) to require that the ceiling concentration limits in

Table 1 of Sec. 503.13 be met.

B. Frequency of Monitoring

Sections 503.16, 503.26, and 503.46 require periodic monitoring of

sewage sludge for pollutants as well as periodic demonstration of

compliance with certain pathogen density and vector attraction

reduction requirements. The frequency of monitoring varies with the

amount of sewage sludge used or disposed. The current regulation allows

the permitting authority, after two years of monitoring, to reduce the

frequency, but in no case may the permitting authority authorize

monitoring less frequently than once a year. EPA proposed to amend the

regulation to authorize the permitting authority to reduce the

frequency of monitoring for pollutants and certain pathogen density

requirements 1 to less than once a year.

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\1\ For example, EPA proposed to authorize the permitting

authority to reduce the frequency of monitoring for the pathogen

densities in Sec. 503.32(a)(5)(ii) and Sec. 503.32(a)(5)(iii). The

frequency of monitoring for all other pathogen densities (e.g., the

1000 MPN per gram of total solids fecal coliform requirement for all

Class A pathogen alternatives), and for the vector attraction

reduction options (e.g., 38 percent volatile solids reduction)

cannot be reduced by the permitting authority.

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Several commenters opposed the proposed change because they

believed it would undermine public confidence in the quality of sewage

sludge that is used or disposed. They stated that consistent monitoring

of sewage sludge is essential to retaining public support for the part

503 regulation.

The Agency does not agree that the proposed change to the frequency

of monitoring requirements means that consistent monitoring of sewage

sludge will not continue. The reduction in the frequency only applies

to pollutant concentrations and certain pathogen density requirements,

and only can be made by the permitting authority.

EPA has decided to modify Sec. 503.16, Sec. 503.26, and Sec. 503.46

to delete the requirement to monitor at least once per year. This

change provides flexibility to permitting authority to tailor

monitoring requirements to specific circumstances without jeopardizing

public health and the environment.

Today's change allows, but does not require, the permitting

authority to reduce the frequency of monitoring. Moreover, the

permitting authority's ability to reduce the monitoring frequency is

limited to monitoring for pollutants and the enteric virus and viable

helminth ova density requirements in pathogen Class A,

[[Page 42554]]

Alternative 3 (see Sec. 503.32(a)(5)(ii) and (5)(iii)). This change

does not apply to any other pathogen density requirement or to the

vector attraction reduction requirements. Further, this change does not

preclude the permitting authority from increasing the frequency of

monitoring even if they reduce the frequency after two years of

monitoring at the part 503 frequency.

Thus, EPA is today amending Sec. 503.16(a)(2), Sec. 503.26(a)(2),

and Sec. 503.46(a)(3) by deleting the phrase ``* * * but in no case

shall the frequency of monitoring be less than once per year when * *

*'' Note that the part 503 frequency of monitoring requirements do not

apply if sewage sludge is not land-applied, surface-disposed, or fired

in a sewage sludge incinerator during the year.

C. Certification Language

Sections 503.17 and 503.27 of the current sewage sludge regulation

require sewage sludge preparers and land appliers, and the owner/

operator of a surface disposal site, respectively, to keep certain

records, and in the case of a Class I sludge management facility, to

report this information to the permitting authority. The regulation

also requires the recordkeepers to certify to compliance with

applicable requirements. Failure to certify may result in significant

penalties.

The October 1995 notice proposed to change the certification

language in the part 503 recordkeeping sections because the effect of

requiring the appropriate person to certify compliance may be to

discourage self-reporting of violations. If a requirement is not being

met, the applicable person obviously cannot certify to compliance with

the requirement without perjury. EPA proposed only to require that the

applicable person certify to the accuracy of the information that was

collected to show compliance. Compliance with the requirement then

would be determined by the permitting authority.

Commenters supported the proposed change. One commenter expressed

concern, however, that the language change may be construed to relieve

preparers of land-applied sewage sludge from meeting certain

requirements. This is not the case. As indicated in Sec. 503.7, the

preparer of land-applied sewage sludge is responsible to ensure that

the applicable land application requirements are met. The change in the

certification language does not relieve a preparer from this duty.

Under the regulation, as amended, the appropriate person must certify

that information collected to show compliance with a requirement was

prepared under his/her direction and supervision in accordance with the

system designed to ensure that qualified personnel gather and evaluate

information properly.

Another commenter suggested that the certifications in the land

application recordkeeping section (Sec. 503.17) for the preparer be

combined into one certification. The commenter also suggested this be

done for the certifications for the applier. EPA has decided to retain

the current certifications in the land application recordkeeping

section without change because they contain the applicable

certification for each requirement (i.e., pollutants, pathogens, and

vector attraction reduction), and ensure there is no confusion about

who is to certify to what.

Today's action amends Sec. 503.17 by revising the certification

language as described above in paragraphs (a)(1)(ii), (a)(2)(ii),

(a)(3)(i)(B), (a)(3)(ii(A), (a)(4)(i)(B), (a)(4)(ii)(A), (a)(5)(i)(B),

(a)(5)(ii)(F), (a)(5)(ii)(H), (a)(5)(ii)(J), (a)(5)(ii)(L),

(a)(6)(iii), and (b)(6). EPA is also amending Sec. 503.27 by revising

the certification language in paragraphs (a)(1)(ii), (a)(2)(ii),

(b)(1)(i), and (b)(2)(i).

D. Time of Application

In the October 25, 1995 Notice, EPA proposed to change certain of

the recordkeeping requirements for land-applied sewage sludge and for

domestic septage applied to agricultural land, forest, or a reclamation

site. EPA proposed to delete the requirement in

Sec. 503.17(a)(5)(ii)(C) and Sec. 503.17(b)(3) to record the time of

application of bulk sewage sludge and domestic sewage, respectively, to

a site. At the same time, EPA proposed to add a new requirement in

Sec. 503.17(a)(4)(ii)(E) for Class B sewage sludge. This change would

require appliers of Class B sewage sludge to record the date bulk

sewage sludge is applied to each site. EPA concluded that, because the

regulation restricts the use of sites to which Class B sewage sludge is

applied,2 it is important to record the date Class B sewage

sludge is land-applied. For the reasons discussed at proposal, EPA is

today adopting these changes.

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\2\ For example, Sec. 503.32(b)(5) prohibits the harvesting of

food crops with harvested parts below the land surface up to 38

months after land application of a Class B sewage sludge.

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E. Definition of pH

EPA also proposed a change to the definition of pH to clarify that

pH should be measured at 25 degrees Centigrade (C) or be converted to

an equivalent value at 25 degrees C. Twenty-five degrees C is the

reference temperature for reporting pH values in the scientific

literature.

Commenters favored the proposed change, which EPA is today adopting

as proposed. Today's notice amends the definition of pH in

Sec. 503.31(g) to read as follows: pH means the logarithm of the

reciprocal of the hydrogen ion concentration measured at 25 deg.

Centigrade or measured at another temperature and then converted to an

equivalent value at 25 deg. Centigrade.

The following equation from Smith and Farrell can be used to adjust

pH values taken at temperatures other than 25 degrees C to equivalent

values at 25 degrees C:

pH correction = [0.03 pH units/1.0 deg. C] x [Temp deg.

Cmeas -25 deg. C]

This equation indicates that for each degree difference between the

measured temperature in degrees C and 25 degrees C, there is a change

in pH of 0.03 units. Thus, if a pH of 12 is measured at 20 degrees C,

the pH at 25 degrees C is 11.85 [12 + (0.03 x -5)]. There is an

inverse relationship between temperature and pH.

F. Class B, Alternative 1--at the Time of Use or Disposal

EPA also proposed to amend Sec. 503.32(b)(2) to change the pathogen

reduction requirements in pathogen Class B, Alternative 1 to allow

those requirements to be met any time before the sewage sludge is used

or disposed. Under the current regulation, these requirements must be

met ``at the time the sewage sludge is used or disposed.''

There were two reasons for EPA's decision to propose this change.

First, the requirement in Sec. 503.32(b)(2) is inconsistent with the

requirements in the two other Class B pathogen

alternatives.3 Part 503 does not require that the

requirements in either Class B, Alternative 2 or Class B, Alternative 3

be met at the time the sewage sludge is used or disposed. For example,

when the requirements in Class B, Alternative 2 are met, the sewage

sludge can be stored and then land-applied. Part 503 does not require

additional treatment after the storage period.

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\3\ These alternatives are Class B, Alternative 2 (treat sewage

sludge in a Process to Significantly Reduce Pathogens (PSRP)) and

Class B, Alternative 3 (treat sewage sludge in a process that is

equivalent to a PSRP). See Sec. 503.32(b)(3) and Sec. 503.32(b)(4).

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Second, EPA concluded that protection of public health and the

environment does not require that the Class B pathogen requirements be

met at the time sewage sludge is used or disposed. The part 503 rule

imposes site restrictions for Class B sewage sludge that is land-

applied and management

[[Page 42555]]

practices for surface-disposed Class B sewage sludge irrespective of

which Class B pathogen alternative is selected. The site restrictions

and management practices allow time for the environment to further

reduce remaining pathogens in the sewage sludge to below detectable

levels.

To make the Class B pathogen alternatives consistent, the Agency

proposed to delete the requirement that the fecal coliform density in

Class B, Alternative 1 be met at the time of use or disposal. This

means that the fecal coliform density requirement can be met any time

(e.g., before storage) before the sewage sludge is used or disposed. As

mentioned above, the site restrictions for land-applied Class B sewage

sludge and the surface disposal management practices provide time for

the environment to further reduce the remaining pathogens in Class B

sewage sludge to below detectable levels.

One commenter opposed the proposed change believing that it would

increase the public health risk, particularly when the sewage sludge is

stored before it is used or disposed. The Agency disagrees and is

adopting the change as proposed.

There is no evidence of increased incidences of disease from

exposure to Class B sewage sludge that is either stored, or used or

disposed. There is evidence, however, that over time the densities of

Salmonella sp. bacteria, enteric viruses, and viable helminth ova in

sewage sludge are reduced to below detectable levels by environmental

conditions. Thus, in EPA's judgement, public health and the environment

are protected when the Class B pathogen requirements and the land

application site restrictions for a Class B sewage sludge are met. With

respect to the concern about stored sewage sludge, the U.S. Department

of Agriculture and EPA are preparing guidance on storage of sewage

sludge. This guidance will address, among other things, good practices

for storing sewage sludge. Today's action amends Sec. 503.32(b)(2)(i)

to indicate that seven representative samples of the sewage sludge that

is used or disposed shall be collected.

G. Site Restriction for Grazing of Animals

EPA also proposed to change the site restriction in

Sec. 503.32(b)(5)(v). The current regulation indicates that animals

shall not be allowed to graze for 30 days after land application of a

Class B sewage sludge. The language in the proposed change indicates

that animals shall not be grazed for 30 days after land application of

a Class B sewage sludge. This restriction applies to the intentional,

not inadvertent, grazing of animals. Commenters supported this change,

and EPA is adopting it today.

H. Vector Attraction Reduction Equivalency

Sewage sludge has a number of qualities that may attract disease-

spreading agents--``vectors''--like birds, flies and rats. The part 503

regulation includes requirements for reducing what is called ``vector

attraction'' potential. The regulation allows use of any of 10 vector

attraction reduction options when sewage sludge is applied to the land

(or 11 options in the case of sewage sludge that is placed on a surface

disposal site). See 40 CFR 503.33.

In the October 25, 1995, notice, EPA proposed to allow the use of

other vector attraction reduction options for any of the eight

treatment options if the permitting authority determined that such an

option was ``equivalent,'' (i.e, equally effective in reducing vector

attraction). This flexible approach is similar to that provided

currently in the part 503 regulation for Class A and Class B pathogen

reduction processes. Processes other than those prescribed in the

regulation may be used to reduce pathogens if the permitting authority

determines they are equivalent.

All of the commenters supported the proposed change. However, none

of the commenters provided information necessary to develop appropriate

measures that could be used to determine whether an option is

equivalent to one of the first eight vector attraction reduction

options. Without such measures, equivalency cannot be determined.

Because no measures exist currently that can be used to determine

whether a vector attraction reduction option is equivalent to one of

the first eight vector attraction reduction options, EPA concluded that

the part 503 regulation should not be amended at this time to allow for

vector attraction reduction equivalency. For this reason, today's

action does not amend Sec. 503.15(c), Sec. 503.25(b), and

Sec. 503.33(a).

The Agency encourages anyone with information that can be used to

develop appropriate measures for vector attraction reduction

equivalency to submit the information to EPA. If measures can be

developed, EPA will consider reproposing the changes to Sec. 503.15(c),

Sec. 503.25(b), and Sec. 503.33(a) to allow an option that is

equivalent to one of the first eight vector attraction reduction

options, if the equivalent option is approved by the permitting

authority.

I. Vector Attraction Reduction at the Time of Use or Disposal

Another proposed change in the October 25th notice was the time

when certain vector attraction reduction options have to be met. Under

the current regulation, vector attraction reduction Options 1 through 8

can be met any time before the sewage sludge is used or disposed. In

the case of Options 9, 10, and 11, however, they must be met at the

time the sewage sludge is used or disposed.

The October 25th notice proposed to change the time when vector

attraction reduction Options 6, 7, and 8 have to be met. The proposed

change required that those options be met at the time the sewage sludge

is used or disposed rather than any time before the sewage sludge is

used or disposed.

As explained in the proposal (60 FR 54775, October 25, 1995),

vector attraction reduction achieved by pH adjustment (Option 6) may

not always be permanent. The target pH conditions in Option 6 allow

sewage sludge to be stored for some period before use or disposal

without the pH dropping. If the sewage sludge is stored for some longer

period of time, however, the pH may drop. At that point, biological

activity in the sewage sludge may resume, and the sewage sludge may

putrefy and attract vectors.

Similarly, in the case of vector attraction reduction Options 7 and

8, the moisture content of the sewage sludge may increase during

storage after the percent solids requirements are met, and biological

activity could increase. This also could cause vectors to be attracted

to the sewage sludge.

EPA received a significant number of comments opposing the proposed

change for Option 6--pH adjustment. Several commenters stated that the

proposed change to Option 6 would require them to adjust the pH of the

sewage sludge twice--once before storage and then again after storage

before use or disposal. This would increase the cost of Option 6.

The commenters assumed incorrectly that part 503 requires the pH of

the sewage sludge to be adjusted prior to storage. EPA only proposed to

require that the pH be adjusted at the time of use or disposal. Thus,

the only cost attributable to part 503 would be the cost of one pH

adjustment at the time of use or disposal.

The commenters presented several other reasons for retaining Option

6 in its current form. These include the following. First, nutrient

problems could result when high pH sewage sludge is land-applied (micro

nutrients

[[Page 42556]]

are less available for plant uptake in high pH soils, particularly in

coastal plains). Second, the high calcium content of the sewage sludge

will lower the agronomic rate for the application site. Third, the

effectiveness of herbicides applied to a site will be reduced because

herbicides are less available in high pH soils. Finally, sewage sludge

with a high pH may induce manganese deficiency because manganese is

more water soluble at high pH and, thus, may be removed from a site

through leaching to ground water. Some commenters also indicated that

if Option 6 is changed, ``unstabilized'' sewage sludge could be

stockpiled or stored and could cause harm to public health. Other

commenters indicated there have been no vector attraction problems in

cases where the pH of the sewage sludge is adjusted prior to storage,

but not at the time of use or disposal.

The only comment on the proposed change to Options 7 and 8 (i.e.,

percent solids) suggest that these options are often relied on by small

POTWs. Thus, the change may have an economic impact on those POTWs.

After further review, EPA concluded that the time when vector

attraction reduction Options 6, 7, and 8 have to be met should not be

changed. In cases where Option 6 is met prior to storage of the sewage

sludge, the pH of the sewage sludge could drop during storage. The

Agency agrees, however, that there have been no documented cases of

vector attraction problems when this occurs, and that it is desirable

to reduce the attractiveness of stored sewage sludge to vectors. In

addition, there are measures that can be taken to keep the pH of the

sewage sludge from dropping during storage. Thus, the time when Option

6 can be met (i.e., any time before the sewage sludge is used or

disposed) remains unchanged.

In the case of Options 7 and 8, the Agency is not aware of any

documented cases concerning protection of public health and the

environment when those options are met prior to use or disposal. Thus,

the time when Options 7 and 8 can be met (i.e., any time before the

sewage sludge is used or disposed) also remains unchanged.

J. Time Period for Vector Attraction Reduction Option 10

In the October 25, 1995, notice, EPA proposed to modify the part

503 regulation to allow the permitting authority to change the time

period sewage sludge has to be incorporated into the soil in vector

attraction reduction Option 10. Vector attraction reduction Option 10

requires incorporation of sewage sludge into the soil within six hours

after it is land-applied or surface-disposed. This reduces the

attraction of vectors to the sewage sludge by placing a barrier between

the sewage sludge and the vectors. EPA proposed this change to allow

the permitting authority to consider site-specific conditions (e.g.,

the remoteness of the land application site) that may affect the time

period during which sewage sludge can be incorporated into the soil.

Commenters supported the proposed change. However, one commenter

asked EPA to modify the language so as to make it clear that, while the

permitting authority may relax the time requirements in Option 10, the

permitting authority could not tighten them. EPA is rejecting this

suggestion because there may be circumstances in which more rapid soil

incorporation is necessary to protect public health and the

environment.

The current regulation authorizes the permitting authority to

modify the existing part 503 requirements where warranted by

circumstances. Section 503.5(a) indicates that a permitting authority

may impose additional or more stringent requirements than the

requirements in part 503 if necessary to protect public health and the

environment. Section 503.5(b) indicates that a State or political

subdivision thereof can establish additional or more stringent

requirements than those in part 503 for any reason.

EPA is today amending Sec. 503.33(b)(10)(i) to allow the permitting

authority to increase the time period during which sewage sludge has to

be incorporated into the soil. Only the permitting authority can

authorize a time period that is different from the time period in part

503.

K. Technical Corrections

In the October 25, 1995 Notice, EPA proposed several technical

corrections to part 503 that were minor in nature and that clarified

some of the technical requirements of the part 503 regulation.

Commenters supported the clarifications. Today's final amendment makes

the following technical corrections to the part 503 regulation with the

one exception discussed below.

1. Sections 503.16(a)(1) and 503.26(a)(1)--Frequency of Monitoring

Sections 503.16(a)(1) and 503.26(a)(1) contain the requirements for

monitoring for pollutants, pathogen densities, and vector attraction

reduction. Those sections indicate there are pathogen density

requirements in Sec. 503.32(b)(3) and (b)(4). This is incorrect.

Today's final amendment deletes the reference to Sec. 503.32(b)(3) and

(b)(4) from Sec. 503.16(a)(1) and Sec. 503.26(a)(1).

Sections 503.16(a)(1) and 503.26(a)(1) also indicate that the

frequency of monitoring requirements apply to vector attraction

reduction Option 5 in Sec. 503.33(b)(5) and Option 6 in

Sec. 503.33(b)(6). This also is incorrect. Today's final amendment

deletes the reference to vector attraction reduction Options 5 and 6

from Sec. 503.16(a)(1) and Sec. 503.26(a)(1).

2. Section 503.17(b)(7)--Recordkeeping for Land Application of Domestic

Septage

Today's final amendment changes Sec. 503.17(b)(7) by changing an

incorrect reference.

3. Section 503.18--Reporting

Today's final amendment corrects the omission of a reporting date

in the part 503 regulation by inserting February 19th in

Sec. 503.18(a)(2).

4. Section 503.21(c)--Contaminate An Aquifer

Today's final amendment corrects the reference to the maximum

contaminant level for nitrate in Sec. 503.21(c). On January 30, 1991,

EPA published a regulation (56 FR 3526) that changed the reference for

the maximum contaminant level for nitrate from 40 CFR 141.11 to 40 CFR

141.62(b). That change was effective July 30, 1992. For this reason,

the reference to the maximum contaminant level for nitrate in the

definition of contaminate an aquifer is being changed to 40 CFR

141.62(b) in today's final rule.

5. Section 503.22(b)--General Requirements

Today's final amendment changes Sec. 503.22(b) by correcting the

statutory reference and by inserting the appropriate date.

6. Section 503.32(a)(3)--Pathogens

In the October 1995 notice, EPA indicated that pathogen Class A,

Alternative 1 only applies to thermal processes such as anaerobic

digestion, and does not apply to composting. Upon further review, EPA

concluded that the time/temperature conditions in Class A, Alternative

1 can be achieved through composting. If the temperature of every

particle of the composted sewage sludge is raised to the appropriate

value for the appropriate time period, Salmonella sp. bacteria, enteric

viruses, and viable helminth ova in the sewage sludge are reduced to

below detectable levels. For this reason, the proposed change to

[[Page 42557]]

Sec. 503.32(a)(3) to exclude composting is not being made.

7. Appendix B to Part 503--Pathogen Treatment Processes

The description of Process to Further Reduce Pathogens (PFRP) No. 6

(Gamma ray irradiation) is corrected to insert the phrase ``at dosages

of at least 1.0 megarad at room temperature (ca. 20 deg. C)'' that was

omitted inadvertently.

V. Final Amendments to the Part 503 Incineration Requirements

A. Compliance Period

In the October 25, 1995, proposal, EPA proposed to amend Sec. 503.2

to require compliance with the revised incineration requirements in

subpart E of part 503 as expeditiously as practicable, but in no case

later than 90 days after publication of the final amendment. If

compliance with the revised subpart E requirements required

construction of new pollution control facilities compliance had to be

achieved as expeditiously as practicable but no later than 12 months

after publication of today's final amendment.

Commenters indicated that 90 days are not enough to comply with the

revised incineration requirements, particularly the requirement to

install continuous emission monitors for total hydrocarbons (THC). EPA

agrees, and has increased the time to comply with the revised

requirements in subpart E.

Today's final rule amends Sec. 503.2 by adding a new paragraph (d)

that, unless otherwise specified in subpart E, requires compliance with

the revised subpart E requirements in the final rule as expeditiously

as practicable, but in no case later than 12 months after the effective

date for the final rule. If new pollution control facilities have to be

constructed to comply with the revised requirements, compliance with

the revised subpart E requirements shall be achieved as expeditiously

as practicable, but no later than 24 months after the effective date

for the final rule.

B. Site-Specific Exemption From Frequency of Monitoring, Recordkeeping,

and Reporting Requirements

The October 25, 1996, notice proposed to amend the applicability

section in Sec. 503.40 to exempt sewage sludge incinerators on a site-

specific basis from the frequency of monitoring, recordkeeping, and

reporting requirements for a specific pollutant in defined

circumstances. Under the proposed approach, if the limit for arsenic,

cadmium, chromium, lead or nickel, determined pursuant to Sec. 503.43,

is significantly higher than the measured concentration for the

pollutant, the permitting authority could exempt the pollutant from the

above requirements so long as the incinerator continued to operate

within the values for the incinerator operating parameters established

during the performance test required by the regulation. The notice

requested comments on whether this approach is appropriate, and how to

determine whether the calculated limit for a pollutant is significantly

higher than the measured concentration of the pollutant in sewage

sludge.

All commenters favored allowing such an exemption. With respect to

how to determine whether a calculated pollutant limit is significantly

higher than the measured concentration, commenters suggested two

different approaches. The first limits the availability of the

exemption for a pollutant to circumstances in which the monthly average

pollutant concentration did not exceed 50 percent of the calculated

limit. The second approach varies the frequency of monitoring, based on

the percentage the measured concentration bore to the calculated limit.

For example, the frequency of monitoring could be reduced to once per

year if the measured concentration is 80 percent of the calculated

limit. If the measured concentration is 60 percent of the calculated

limit or less, there would be no monitoring requirement for that

pollutant.

After considering this proposed change further, EPA has decided not

to amend the regulation for the following reasons. Although several

commenters offered suggestions on how to determine whether a calculated

limit is significantly higher than the measured concentration for a

pollutant, no commenter provided any test the permit writer could apply

for ensuring that, in fact, the actual concentration for the pollutant

falls substantially below the calculated limit. Moreover, there are

questions about how much data are needed to support an exemption and

the period of the exemption (e.g., one year, five years, or forever).

In addition, there are many factors that could affect the actual

concentration of a pollutant in sewage sludge (e.g., variability of the

pollutant in the influent to the treatment works).

Another concern EPA has about the proposed change is the assumption

that the incinerator will be operated as it was during the performance

test. There are many factors that affect the performance test results

(e.g., feed rate and excess oxygen). If these factors change, the

calculated limits for a pollutant could change.

Given the concerns about changes in both the calculated limit and

the measured concentration of a pollutant in sewage sludge, EPA

concluded that the part 503 regulation should not provide for a site-

specific exemption from the frequency of monitoring, recordkeeping, and

reporting requirements in subpart E. Thus, today's notice does not

amend Sec. 503.40 to add a new paragraph (d).

C. Pollutant Limits for Arsenic, Cadmium, Chromium, Lead and Nickel

In the October 25, 1995 notice, EPA proposed several changes to the

requirements in Sec. 503.43 for sewage sludge that is incinerated. As

explained in greater detail in the preamble to the proposal (60 FR

54777-54779, October 25, 1995), 40 CFR 503.43 establishes limits on the

allowable ``daily concentration'' of arsenic, cadmium, chromium, lead

and nickel in sewage sludge. The allowable limits are calculated using

equations set forth in the regulation, and are dependent on a number of

factors that vary with specific conditions at an incinerator site. To

calculate the limit for each of the five pollutants, the regulation

requires determination of two factors that are dependent on site-

specific conditions. They are: (1) A dispersion factor (DF)--how

pollutants are dispersed when they exit the incinerator stack, and (2)

the incinerator's control efficiency (CE)--how efficiently the

incinerator removes a pollutant in the sewage sludge that is

incinerated. The regulation requires use of an air dispersion model to

determine the DF and a performance test to establish the CE, both of

which must be specified by the permitting authority. In addition, in

the case of chromium, the regulation requires the permitting authority

to determine whether the risk specific concentration (RSC) for

chromium, which is used to establish the allowable chromium sewage

sludge pollutant concentration, should be based on default values

provided in the regulation (Table 2 of Sec. 503.43) or determined by a

site-specific calculation.

The requirement for site-specific action by the permitting

authority has significant implications for compliance and enforcement

of the regulation. Site-by-site tailoring of a particular incinerator's

requirements effectively defers the determination of an individual

incinerator's limits until action by the permitting authority. Given

the resource-intensive nature of these site-by-site determinations and

constraints on available resources, EPA

[[Page 42558]]

proposed to adopt a different approach. The Agency proposed to delete

the requirement for the permitting authority to approve the air

dispersion modeling and performance tests used to determine DF and CE,

respectively, as well as modify the requirement for the permitting

authority to determine the appropriate chromium RSC. EPA also proposed

to clarify the definition of the allowable concentration of a pollutant

in sewage sludge.

1. Average Daily Concentration

EPA proposed to revise 40 CFR 503.43(c)(1) and (d)(1) to clarify

that the calculated sewage sludge concentration is an average daily

concentration based on the number of days in a month that the

incinerator operates. This change made the calculated concentration

consistent with the risk specific concentration (i.e., the allowable

ambient air concentration for a pollutant developed through risk

assessment) for a pollutant.

Comments on this proposed changed were generally favorable, but the

commenters asked for a clarification with respect to the number of days

in the month the incinerator operates. Commenters questioned whether

the calculated limit was a monthly average. Upon further review, EPA

concluded that it is not appropriate to calculate the allowable

concentration of a pollutant in sewage sludge fed to a sewage sludge

incinerator using the number of days in the month the incinerator

operates. Instead, the average daily concentration should be the

arithmetic mean of the concentration of a pollutant in the samples

collected and analyzed during a month. Thus, if one sample is collected

and analyzed during the month, the average daily concentration is the

concentration of a pollutant in that sample. If two samples are

collected and analyzed during the month, the average daily

concentration is the arithmetic mean of the concentration of a

pollutant in those two samples. Likewise, if only one sample is

collected and analyzed during the year, the average daily concentration

is the concentration for a pollutant in that one sample.

After considering the comments on the proposed change to the

allowable concentration of a pollutant in sewage sludge, EPA concluded

that the allowable concentration should be an average daily

concentration. Thus, today's notice amends Sec. 503.43(c)(1) and (d)(1)

by changing the definition of ``C'' in equations (4) and (5),

respectively, to average daily concentration. Today's notice also

amends Sec. 503.41--Special Definition--by adding the following

definition for average daily concentration: ``Average daily

concentration is the arithmetic mean of the concentration of a

pollutant in milligrams per kilogram of sewage sludge (dry weight

basis) in the samples collected and analyzed in a month.''

2. Approval of Air Dispersion Model and Performance Test

As noted above, the October 1995 notice proposed to amend the

regulation to delete the requirement in Sec. 503.43(c)(2), (c)(3),

(d)(4), and (d)(5) for the permitting authority to specify the air

dispersion model and performance test used to calculate the sewage

sludge pollutant limits. EPA received no comments on these proposed

changes. Therefore, today's notice amends Sec. 503.43 (c)(2), (c)(3),

(d)(4), and (d)(5) by deleting the requirement for the permitting

authority to specify how to meet these requirements.

EPA also proposed amending Sec. 503.43(d)(3) to delete the

requirement for the permitting authority to specify one of the two

means of calculating the risk specific concentration for chromium. EPA

received only one comment, and it favored the proposed change. Thus,

today's final rule amends Sec. 503.43(d)(3) by deleting the requirement

for the permitting authority to specify how to meet this requirement.

The October 1995 notice also proposed to add a new paragraph (e) to

Sec. 503.43. This paragraph contains requirements for air dispersion

modeling and performance tests to serve the purpose of the deleted

requirements in Sec. 503.43(c)(2), (c)(3), (d)(4), and (d)(5) that the

permitting authority specify the air dispersion model and performance

test.

The proposed Sec. 503.43(e)(1) required that any air dispersion

model and performance test be ``consistent with good air pollution

control practices for minimizing air pollution.'' One commenter

objected to this provision asserting that such a requirement was

inappropriate. In the commenter's view, an air dispersion model and a

performance test are used to measure something, not to minimize air

emissions. EPA concurs with the comment on Sec. 503.43(e)(1). Thus,

today's final amendment only requires that the air dispersion model be

appropriate for the geographical, physical, and population

characteristics at the incinerator site, and that the performance test

be appropriate for the type of sewage sludge incinerator.

Proposed Sec. 503.43(e)(2) required that an air dispersion modeling

protocol be submitted to the permitting authority within 30 days of the

publication date of this final amendment. The permitting authority

would then have 30 days to review the protocol, including the selected

air dispersion model, and provide comments on the protocol. If the

permitting authority did not object within 30 days, the protocol could

be used to determine the dispersion factor for the incinerator site. No

comments were received on this proposed requirement.

Upon further review, EPA concluded that the air dispersion model

protocol should not be submitted to the permitting authority 30 days

from the date of publication of this final amendment because the Agency

lacks the resources to review and comment on the protocol within 30

days after it is received. Instead, today's action amends

Sec. 503.43(e)(2) to require that results of air dispersion modeling

initiated after September 3, 1999, be submitted to the permitting

authority no later than 30 days after completion of the modeling. This

requirement does not apply to air dispersion modeling completed prior

to September 3, 1999.

EPA encourages the person who conducts the air dispersion modeling

to coordinate with the permitting authority prior to conducting the

modeling. This could prevent future problems if the permitting

authority has concerns about the air dispersion modeling.

As indicated in the October 1995 notice, EPA has published several

guidance documents that contain recommendations on how to select

appropriate air dispersion models. These models consider such site-

specific factors as stack height, stack diameter, stack gas

temperature, exit velocity and topography of surrounding terrain. See

Guidelines on Air Quality Models in Appendix W to 40 CFR part 51 and in

the U.S. EPA, ``Technical Support Document for Sewage Sludge

Incineration'' at Section 5.6.1 (EPA 822/R-93-003, November 1992).

Information on air quality models also can be obtained from the Support

Center for Regulatory Air Models (SCRAM) on the Technology Transfer

Network, (http://ttnwww.rtpnc.epa.gov/).

Proposed Sec. 503.43(e)(3) contained the minimum procedures for

conducting a performance test. A performance test measures the degree

to which a sewage sludge incinerator and associated air pollution

control devices remove a pollutant. As previously explained, the

pollutant control efficiency from a performance test is used to

calculate the allowable concentration of a pollutant in sewage sludge

fired in the incinerator.

[[Page 42559]]

The procedures in the proposed Sec. 503.43(e)(3) parallel the

procedures in 40 CFR 60.8, a regulation that describes the general

procedures for conducting performance testing under the Clean Air Act.

EPA concluded that it is necessary to specify minimum procedures for

conducting performance tests now that the part 503 incineration

requirements are self-implementing.

The procedures in proposed Sec. 503.43(e)(3)(i) require that the

performance test be conducted under representative incinerator

conditions at the highest expected sewage sludge feed rate within

design specifications. A commenter suggested that EPA should recognize

the variability in the feed rate during the operation of the sewage

sludge incinerator.

EPA agrees that the feed rate used in performance tests may well

differ from the sewage sludge feed rate during day-to-day operation of

the incinerator. Part 503 takes this into account by requiring that the

``highest expected'' feed rate be used in the performance test. Because

the actual feed rate is expected to be equal to or less than the

highest expected feed rate, the actual feed rate should not cause the

control efficiency for a pollutant to decrease during the day-to-day

operation of the incinerator.

The above comment is more applicable to the feed rate used to

calculate the limit for a pollutant than to the feed rate during a

performance test. As provided in the current rule, the sewage sludge

feed rate used in the equations in Sec. 503.43(c)(1) and (d)(1) to

calculate the limit for a pollutant takes the feed rate during

operation into account. The feed rate used in these equations is either

the average daily amount of sewage sludge fired in all sewage sludge

incinerators within the property line of the site where the sewage

sludge incinerators are located for the number of days in a 365 day

period that each sewage sludge incinerator operates, or the average

daily design capacity for all sewage sludge incinerators within the

property line of the site where the sewage sludge incinerators are

located (see Sec. 503.41(j)). This definition recognizes potential

variability in the actual feed rate, and accounts for the variability

by providing for averaging over a 365 day period.

The October 25, 1995, proposal required in Sec. 503.43(e)(3)(ii)

that the permitting authority be notified at least 30 days prior to a

performance test so that the permitting authority may have the

opportunity to comment on the test protocol and test methods, and to

observe the test. This requirement does not apply in cases where

performance tests were conducted prior to September 3, 1999. This

change is included in today's final rule as proposed.

EPA has decided not to adopt a provision it proposed as

Sec. 503.43(e)(3)(iii) that would have required that performance

testing facilities contain safe sampling platforms and safe access to

them because that provision is not related directly to the use or

disposal of sewage sludge. In addition, for sewage sludge incinerators

subject to 40 CFR part 60, subpart O, the proposed provision reflects a

similar provision in 40 CFR 60.8 concerning performance tests. There

also may be other federal or state safety requirements that govern the

way performance tests are conducted. Therefore, the Agency concluded

that this provision does not need to be in today's final rule.

Today's final Sec. 503.43(e)(3)(iii), proposed as subparagraph

(e)(3)(iv), concerns the number of runs for a performance test. Each

performance test shall consist of three runs. The arithmetic mean of

the results of the three runs is the control efficiency for a

pollutant. All commenters on this proposal agreed with the requirement.

Thus, this requirement in today's final rule is the same as it was in

the proposal.

Today's action also promulgates Sec. 503.43(e)(4) as proposed on

October 25, 1995. This provision requires that the calculated pollutant

limits be submitted to the permitting authority within 30 days of

completion of air dispersion modeling and performance tests.

As proposed, Sec. 503.43(e)(5) requires new air dispersion modeling

and performance testing when there are ``significant changes'' in

specific aspects of the site or in incinerator operating conditions.

One commenter asked how high above the feed rate in the performance

tests or the feed rate used to calculate pollutant limits can the

actual feed rate be before a new performance test or a new limit for a

pollutant is required. One possibility is to allow the actual feed rate

to increase by a certain percentage (e.g., 10 percent) of the feed rate

in the performance test or the feed rate used to calculate a limit

before a new performance test has to be conducted or a new limit for a

pollutant calculated.

Another possibility is to decide how much the actual feed rate can

increase on a case-by-case basis. Under this approach, all the factors

that affect the decision on whether to conduct a new performance test

or calculate a new limit can be considered. For example, if the

measured concentration of a pollutant in sewage sludge is significantly

lower than the calculated limit for the pollutant, public health may

still be protected if the feed rate increases by more than 10 percent,

while in another case, an increase of 10 percent in the feed rate may

result in a pollutant limit being exceeded.

Today's final rule does not specify when new performance tests have

to be conducted or when new pollutant limits have to be calculated.

Section 503.43(e)(5) indicates that significant changes in incinerator

operating conditions will require that new performance tests be

conducted. The decision on whether a change in operating conditions,

including feed rate, is significant will be determined on a case-by-

case basis by the permitting authority. Protection of public health

should be the major factor in deciding whether to conduct new

performance tests or calculate new pollutant limits.

3. Technical Corrections

The October 1995 notice also proposed three technical corrections

to Sec. 503.43(d)(1) and (d)(2). Two of the changes corrected

typographical errors in the definition of terms in (d)(1) and the other

change corrected a reference in (d)(2). These changes are included in

today's final rule.

4. Air Emissions Analytical Methods

The preamble in the October 1995 notice requested comments on

whether to specify methods to analyze emissions from sewage sludge

incinerator stacks in part 503. Commenters on the proposal recommended

that EPA not include specific test methods for air emissions in part

503 because EPA approved methods already are required in other

regulations. EPA agrees with the commenters.

EPA's Office of Air Quality Planning and Standards has approved

Method 29 in 40 CFR part 60, Appendix A as a method for determining

compliance with the particulate emissions standards in subpart O of 40

CFR part 60 (Standards of Performance for Sewage Treatment Plants), and

the beryllium and mercury emissions standards in subparts C and E,

respectively, of 40 CFR part 61 (National Emission Standards for

Hazardous Air Pollutants). This method only requires that one sampling

train be used. The methods in 40 CFR part 266 (Boilers and Industrial

Furnaces), Appendix IX, section 3.1 also can be used to measure

emission rates. When those methods are used, more than one sampling

train is needed. Because both methods are available, today's final rule

does not specify a method to measure emission rates. EPA recommends,

however, that Method 29

[[Page 42560]]

be used during the performance test required by part 503 because that

method only requires one sampling train.

D. Management Practices

Sections 503.45(a)(1) and Sec. 503.45(b)-(d) of the sewage sludge

regulation require the installation of instruments that continuously

monitor total hydrocarbons (THC) concentration, oxygen concentration,

information to determine moisture content in the sewage sludge

incinerator stack emissions, and combustion temperature, respectively.

These instruments must be installed, calibrated, operated, and

maintained ``as specified by the permitting authority.''

As explained in the October 1995 proposal (60 FR 54779), the part

503 regulation required the permitting authority to specify the manner

in which the above instruments are installed calibrated, operated, and

maintained because, at the time the regulation was published, there was

only limited EPA guidance in this area. Because there is now EPA

guidance on how to install, calibrate, operate, and maintain the above

instruments, EPA proposed to amend Sec. 503.45(a)(1) and

Sec. 503.45(b)-(d) to delete the requirement that the permitting

authority specify how the instruments required by those sections are

installed, calibrated, operated, and maintained. With one exception,

all comments received on the proposed changes concurred with the

changes.

EPA received one comment suggesting alternative means of

demonstrating compliance with the total hydrocarbons or carbon monoxide

operational standards. The commenter suggested that EPA consider

providing for the site-specific establishment and continuous monitoring

of a minimum incinerator exhaust temperature, in lieu of continuous

monitoring of total hydrocarbons or carbon monoxide. The commenter also

suggested that the incinerator owner/operator be allowed to demonstrate

a site-specific correlation between total hydrocarbons and carbon

monoxide emissions as an alternative method of demonstrating compliance

with either emissions limit. The Agency did not propose either of these

alternatives in the October 25, 1995 proposal. However, in the preamble

to the proposal, the Agency stated that it would study monitoring for

other parameters, including temperature, to measure compliance with

either the total hydrocarbon limit or the carbon monoxide limit and

would decide whether further amendments to part 503 were needed as a

result of the study. (60 FR 54779). EPA undertook this study and

produced a report on the feasibility of alternatives to continuous

monitoring of total hydrocarbons or carbon monoxide. A copy of the

report, entitled ``An Investigation of Alternative Means for

Demonstrating Compliance with the part 503 Total Hydrocarbon

Operational Standards,'' EPA 822-R-98-001 is in the rulemaking docket.

The study indicated that, while technically feasible on a site-specific

basis , either of these options would be extremely resource intensive

and would involve the permitting authority in complex procedures to

determine and approve site-specific temperature limits or site-specific

total hydrocarbons/carbon monoxide correlations. As a result of these

findings, the Agency, has decided not to pursue either the option of

establishing and continuously monitoring for site-specific temperature

limits or the option of establishing site-specific correlations between

total hydrocarbons and carbon monoxide emissions in lieu of complying

independently with either the 100 ppm total hydrocarbons or carbon

monoxide emissions limits. However, the Agency invites the public to

comment on whether these options for demonstrating compliance should be

pursued further and to provide any additional information to supplement

the report that EPA relied on in deciding not to allow for these

alternatives at this time. Thus, the above changes are included in

today's final rule.

In the October 1995 notice, EPA also proposed to delete the

requirements in Sec. 503.45 (e) and (f) for the permitting authority to

specify the maximum combustion temperature for a sewage sludge

incinerator and the values for the operating parameters for the air

pollution control devices, respectively. These proposed changes help

make the part 503 incineration requirements self-implementing.

Commenters supported the proposed modifications, and they are included

in today's final rule.

EPA also proposed to amend Sec. 503.45 (e) to require that the

maximum combustion temperature for the incinerator, which is based on

information obtained during the performance test, not be exceeded

significantly. EPA recognized that the combustion temperature of a

sewage sludge incinerator could vary. Consequently, the Agency asked

for comment on: (1) What averaging period should be used to determine

the maximum allowable combustion temperature (daily average, hourly?)

and (2) how much the maximum combustion temperature could vary from the

performance test maximum combustion temperature.

Commenters' suggestions ranged from measuring maximum operating

combustion temperature as a hourly average to a daily average, with

temperature monitored hourly. EPA concluded that the operating

combustion temperature for a sewage sludge incinerator should be the

arithmetic mean of the hourly average temperature in the hottest zone

of the furnace for the hours during the day the incinerator operates,

and that the maximum allowable operating combustion temperature be

based on the average combustion temperature during the performance test

(see discussion below). Any variation in the operating combustion

temperature over a day is not expected to significantly impact either

the concentration of a pollutant in the emissions from the sewage

sludge incinerator or the ambient air concentration for the pollutant

and, therefore, is not expected to significantly impact public health.

Thus, EPA is amending the part 503 regulation to add a new definition

to Sec. 503.41--Special Definitions--for incinerator operating

combustion temperature as follows: ``Incinerator operating combustion

temperature is the arithmetic mean of the temperature readings in the

hottest zone of the furnace recorded in a day (24 hours) when the

temperature is averaged and recorded at least hourly during the hours

the incinerator operates in a day.''

As indicated above, EPA proposed that the maximum allowable

operating combustion temperature be based on information obtained

during the incinerator performance test required by Sec. 503.43 (c)(3)

and (d)(5). The proposed regulation required three separate runs for

each performance test. Commenters argued that the maximum combustion

temperature from each of the runs should be averaged to determine the

maximum combustion temperature for the performance test and that

temperature should then be increased by a certain percentage (e.g., 20

percent) to determine the maximum operating combustion temperature.

EPA agrees that an average should be used to describe the

combustion temperature in a performance test. The Agency does not

agree, however, that the maximum temperature from each run should be

averaged and that average increased by a certain percentage to obtain

the maximum operating combustion temperature. EPA concluded that the

performance test combustion temperature should be the arithmetic mean

of the average combustion temperature in the hottest

[[Page 42561]]

zone of the furnace from each of the runs in a performance test. This

accounts for variability in the combustion temperature because all of

the continuously measured temperature readings are used to calculate

the arithmetic mean. Thus, today's final rule amends Sec. 503.41--

Special Definitions--by adding the following definition for performance

test combustion temperature: ``Performance test combustion temperature

is the arithmetic mean of the average combustion temperature in the

hottest zone of the furnace for each of the runs in a performance

test.''

EPA also agrees that the performance test combustion temperature

should be increased by a certain percentage to determine the maximum

operating combustion temperature for an incinerator. After further

review, EPA concluded that a 20 percent increase in the performance

test combustion temperature is reasonable. The change in control

efficiency resulting from a 20 percent increase in performance test

combustion temperature is not expected to be significant because that

change is not expected to result in a significant change in the

concentration of a pollutant in the incinerator stack emissions and is

not expected to result in a significant change in the allowable limit

for a pollutant (control efficiency is one of the variables used to

calculate the limit for a pollutant). Because neither the stack

emissions concentration nor the allowable limit for a pollutant are

expected to change significantly, public health is not expected to be

impacted significantly with a 20 percent increase in performance test

combustion temperature on an average daily basis. This is particularly

true with respect to the pollutant limits because the limits are

designed to protect public health from a lifetime of exposure (i.e., 70

years). In addition, most of the calculated pollutant limits for sewage

sludge incinerators are higher (sometimes several orders of magnitude

higher) than the measured sewage sludge concentration for a pollutant.

Also, as indicated in the report titled ``Human Health Risk Assessment

for Use & Disposal of Sewage Sludge: Benefits of the Regulation'' (EPA

822-R-93-005, November 1992), the estimated aggregate risk (i.e., risk

to the entire exposed population) from exposure to emissions from

sewage sludge incinerators prior to the establishment of the part 503

incineration requirements (i.e., baseline risk) is low. Because the

baseline aggregate risk is low, a 20 percent increase in the

performance test combustion temperature on an average daily basis is

not expected to impact the risk to the exposed population from

incineration of sewage sludge.

A 20 percent increase also provides flexibility needed to operate a

sewage sludge incinerator, particularly multiple hearth incinerators.

In addition, one of the commenters on the proposal recommended a 20

percent increase even though their recommended increase was in the

maximum performance test combustion temperature. As mentioned above,

EPA concluded that it is reasonable to apply the increase to the

average temperature from the performance test. Thus, Sec. 503.45(e) in

today's final rule indicates that the arithmetic mean of the

temperature readings in the hottest zone of the furnace recorded in a

day when the temperature is average and recorded at least daily (i.e.,

the operating combustion temperature) shall not exceed the arithmetic

mean of the average combustion temperature in the hottest zone of the

furnace for each of the runs in the performance test (i.e., the

performance test combustion temperature) by more than 20 percent.

Today's final rule amends Sec. 503.45(f) to delete the requirement

that the permitting authority specify the air pollution control device

operating parameters. Instead, Sec. 503.45(f) requires that the air

pollution control device be appropriate for the sewage sludge

incinerator and that the operating parameters for the air pollution

control device indicate adequate performance of the device. As

explained in the preamble to the proposal (60 FR 54780, October 25,

1995), EPA intended that the values for the air pollution control

device operating parameters be expressed as a range, and requested

comment on what the allowable range of values should be relative to the

values determined during the performance test. EPA also requested

comments on whether to standardize operating parameters for different

air pollution control devices in today's final rule. Operating

parameters for different types of air pollution control devices are

presented in the ``Technical Support Document for Sewage Sludge

Incineration'' in section 7.5 and Appendix M (EPA 822/R-93-003,

November 1992).

All commenters opposed EPA establishing standardized operating

parameters in part 503 for the different types of air pollution control

devices. The operating parameters and the value for the operating

parameter should be established on a case-by-case basis. However, if

EPA decides to standardize operating parameters, commenters recommended

that EPA establish average daily values, and allow flexibility in

selecting the values for the operating parameters (e.g., allow values

for the operating parameters that are as low as 70 percent of the

average daily value in the performance test).

Because the operating parameters vary depending on the type of air

pollution control device used and the values for the operating

parameters depend on site-specific conditions, EPA agrees that those

parameters and values should be determined on a case-by-case basis.

Thus, today's Sec. 503.45(f) does not standardize the operating

parameters for the different types of air pollution control devices.

Section 503.45(f) in the proposal indicated that operation of the

sewage sludge incinerator shall not cause a significant exceedence of

the values for the air pollution control device operating parameters.

One commenter requested that EPA define ``significant exceedence'' as

the phrase was used in proposed Sec. 503.45(f). The commenter suggested

that EPA employ a concept that uses 20 percent and 40 percent ranges to

define ``significant exceedence.''

Subpart O of 40 CFR part 60 (Standards for Performance for Sewage

Sludge Plants) applies to sewage sludge incinerators when the material

charged is at least 10 percent sewage sludge or when more than 2205

pounds of sewage sludge are charged per day, and when construction or

modification of the incinerator commences after June 11, 1973. That

subpart contains the requirements for the operation of the incinerator

air pollution control device. For this reason, Sec. 503.45 (f) in

today's final rule requires that for sewage sludge incinerators subject

to subpart O of 40 CFR part 60, operation of the air pollution control

device shall not violate the requirements for the air pollution control

device in subpart O.

For all other sewage sludge incinerators, Sec. 503.45 (f) in

today's final rule indicates that operation of the sewage sludge

incinerator shall not cause a significant exceedence of the average

value for the air pollution control device operating parameters from

the performance tests required by Sec. 503.43 (c)(3) and (d)(5). EPA

decided not to define ``significant exceedance'' in this case at this

time. The Agency is considering whether to request comments on the

allowable ranges for the values for the air pollution control device

parameters in a subsequent proposal to amend the part 503 regulation.

[[Page 42562]]

EPA also proposed to add a new section Sec. 503.45(h). As proposed,

this provision would require that the instruments required in

Sec. 503.45(a)-(d) be appropriate for the type of sewage sludge

incinerator, and shall be installed, calibrated, operated, and

maintained ``consistent with good air pollution control practice for

minimizing air emissions.'' EPA received only one comment on this

provision. The commenter argued that the phrase ``consistent with good

air pollution control practice for minimizing air emissions'' is not

pertinent. EPA agrees that the requirement to install certain

instruments for measuring emissions, temperature, etc. is not directly

related to emissions capture, and has deleted this phrase from the

final rule.

E. Frequency of Monitoring

EPA proposed several changes to the frequency of monitoring

requirements in Sec. 503.46 for sewage sludge incinerators. 60 FR

54780-82, October 25, 1995.

1. Mercury and beryllium. In the case of mercury and beryllium

4, EPA proposed to delete the requirement that the

permitting authority specify the monitoring frequency, and that the

frequency be the frequency in the National Emission Standard for

Hazardous Air Pollutant (NESHAP) for beryllium in subpart C of 40 CFR

part 61 and in the NESHAP for mercury in subpart E of 40 CFR part 61.

EPA also requested comment on whether to establish a periodic

monitoring frequency for beryllium and mercury for sewage sludge

incinerators that is different from the monitoring frequencies in the

NESHAP.

---------------------------------------------------------------------------

\4\ The preamble to the proposal explains the current standards

and monitoring requirements for incineration of sewage sludge

containing mercury and beryllium. 60 FR 54780, October 25, 1995.

---------------------------------------------------------------------------

The October 1995 notice stated that the Agency was considering

three options for the frequency of monitoring for mercury. The options

were: (1) Periodic (quarterly or annual) stack or sewage sludge

sampling, (2) periodic (monthly, quarterly, or annual) sewage sludge

sampling, and (3) sewage sludge sampling based on the amount of sewage

sludge fired in a sewage sludge incinerator. For beryllium, EPA

indicated that periodic stack sampling only for sewage sludge

incinerators that must comply with the beryllium emission standard in

40 CFR 61.32(a) was being considered.

Most of commenters opposed additional beryllium and mercury

monitoring beyond that required by the current NESHAP for beryllium and

mercury. One commenter recommended a semi-annual frequency for mercury

monitoring if mercury in the stack emissions exceeds 1600 grams per day

(the NESHAP requires annual monitoring if mercury in the stack

emissions exceeds 1600 grams per day). Another commenter recommended

sewage sludge sampling for mercury according to the part 503 frequency

of monitoring for arsenic, cadmium, chromium, lead, and nickel rather

than stack emission sampling. Another commenter recommended no stack

sampling and that the monitoring frequency for mercury be based on the

amount of sewage sludge fired in a sewage sludge incinerator.

5

---------------------------------------------------------------------------

\5\ One commenter also requested clarification of the

applicability of the beryllium NESHAP to sewage sludge incinerators.

The beryllium NESHAP applies to incinerators that process beryllium-

containing waste, as defined in 40 CFR 61.31(g). Thus, if sewage

sludge contains beryllium-containing waste and the sewage sludge is

fired in a sewage sludge incinerator, the sewage sludge incinerator

is subject to the beryllium NESHAP.

---------------------------------------------------------------------------

EPA has decided not to establish additional monitoring requirements

for beryllium and mercury. The Agency concluded that monitoring

frequencies in the beryllium and mercury NESHAPs are reasonable. Thus,

today's final regulation amends Sec. 503.46(a)(1) to delete the

requirement for the permitting authority to designate the frequency of

monitoring for beryllium and mercury in emissions. The regulation, as

amended, now provides that the monitoring frequency for beryllium and

mercury is the frequency in the beryllium and mercury NESHAP,

respectively.

Even though the mercury NESHAP only requires annual monitoring if

mercury in the stack emissions exceeds 1600 grams per day, the

frequency can be increased on a case-by-case basis by the permitting

authority when necessary to protect public health and the environment

(see Sec. 503.5). Thus, in areas like the Great Lakes where mercury

emissions are a major concern, the monitoring frequency for mercury may

be increased by the permitting authority, or the person who fires

sewage sludge in a sewage sludge incinerator could elect to increase

the mercury monitoring frequency.

2. Reduction in frequency of sewage sludge monitoring. The October

1995 notice also proposed to amend Sec. 503.46(a)(3). This section

currently allows the permitting authority to reduce the frequency of

monitoring for pollutants after the sewage sludge has been monitored

for two years at the frequency in Table 1 of Sec. 503.46. In no event,

however, may monitoring be less frequent than once per year. EPA

proposed to delete the requirement for monitoring at least once per

year.

Commenters supported the proposed change. Thus, for the reasons

explained above in the previous discussions for the frequency of

monitoring for land application and surface disposal, today's final

rule amends Sec. 503.46(a)(3) by deleting the at-least-once-per-year

monitoring frequency requirement.

3. Continuous monitoring of THC, oxygen concentration, information

to determine moisture content, and combustion temperature. As

previously explained, the current regulation requires continuous

monitoring of THC, oxygen concentration, information to determine

moisture content, and combustion temperature. EPA proposed in the

October 1995 notice to amend this requirement so as to permit

monitoring at less frequent intervals. The Agency requested comment on

how to determine when less frequent monitoring should be authorized

(e.g., should the frequency of monitoring be based on the amount of

sewage sludge fired annually or on the number of days in a year an

incinerator operates?).

All commenters supported the proposed change to delete the

requirement for continuous monitoring for the four parameters. They

also offered several recommendations on when to allow less than

continuous monitoring of the exit gas. Some commenters recommended

exempting fluidized bed incinerators from the continuous monitoring

requirement entirely or any incinerator after two years of continuous

monitoring if the monitoring results indicate minimal THC

concentrations in the emissions. Others recommended exempting an

incinerator when the amount of sewage sludge fired is below a specified

amount or exempting an incinerator if a demonstration can be made that

temperature can be measured continuously in lieu of measuring THC

continuously. After reviewing the comments, EPA has decided not to

adopt any of the recommendations. EPA concluded that the commenters had

failed to provide adequate technical or scientific support for

relieving an incinerator from the continuous monitoring requirements.

The commenters failed to show how compliance with the applicable

requirements could be demonstrated in the absence of continuous

monitoring.

4. Operating parameters for air pollution control devices. As

explained in the preamble to the proposal (60 FR 54779, October 25,

1995), and as discussed above, Sec. 503.45 currently requires the

operation of a sewage

[[Page 42563]]

sludge incinerator's air pollution control device be specified by the

permitting authority. Section 503.46(c) requires the permitting

authority to specify the frequency of monitoring for the air pollution

control device operating parameters. EPA proposed to change

Sec. 503.46(c) to delete the requirement for the permitting authority

to specify the monitoring frequency for air pollution control device

operating parameters and to require that those parameters be monitored

at least daily. Commenters supported these proposed changes.

Currently, incinerators that charge more than 10 percent sewage

sludge (dry weight) or that charge more than 2205 pounds of sewage

sludge per day; that commence construction or modification after June

11, 1973; and that have a wet scrubbing device are required to measure

and record the pressure drop of the gas flow through the wet scrubber

continuously (see 40 CFR 60.153). Incinerators that meet the first two

of the above requirements and that have another type of air pollution

control device also may have to monitor air pollution control device

operating parameters continuously, if required by the EPA

Administrator. The Agency decided not to establish additional frequency

of monitoring requirements in today's final rule for sewage sludge

incinerators subject to 40 CFR part 60. Thus, the final rule indicates

for sewage sludge incinerators subject to part 60, the frequency of

monitoring for the air pollution control device operating parameters

shall be the frequency of monitoring in subpart O of part 60.

For all other sewage sludge incinerators, the frequency of

monitoring for the air pollution control device operating parameters in

today's rule is at least daily, as proposed. EPA is considering whether

to establish a continuous monitoring requirement for the air pollution

control device operating parameters in a subsequent proposal to amend

the part 503 regulation. Continuous monitoring is consistent with the

monitoring requirements for air pollution control device operating

parameters now being considered by other EPA programs. Until a

different frequency of monitoring requirement is established, however,

the frequency of monitoring for the air pollution control device

operating parameters for sewage sludge incinerators not subject to the

requirements in subpart O of part 60 is at least daily.

F. Recordkeeping

Today's action amends Sec. 503.47(f) by changing the requirement to

record the maximum combustion temperature for the sewage sludge

incinerator to a requirement to record the operating combustion

temperatures for the sewage sludge incinerator. This change makes

Sec. 503.47(f) consistent with the new definition of operating

combustion temperature in Sec. 503.41(i).

VI. Final Amendment to Part 403

Part 503, as published on February 19, 1993, restricted the total

chromium concentration of land-applied sewage sludge to prevent

possible plant injury (i.e., phytotoxicity). On November 15, 1994, the

U.S. Court of Appeals for the D.C. Circuit remanded the total chromium

land application pollutant limits for modification or additional

justification, concluding that EPA lacked an adequate evidentiary basis

for the risk-based total chromium limits. Leather Industries of America

v. Environmental Protection Agency, 40 F.3d 392 (DC Cir. 1994). On

October 25, 1995, EPA promulgated a final rule that deleted total

chromium from the pollutants regulated when sewage sludge is applied to

the land (60 FR 54764, October 25, 1995). EPA concluded that there is

no current basis for establishing total chromium limits for land-

applied sewage sludge.

At the same time EPA deleted the total chromium limits from the

part 503 land application requirements, the Agency took two other

actions. First, EPA removed total chromium from the list of pollutants

in Appendix G--Section I (40 CFR part 403) for which a removal credit

is available when sewage sludge is land-applied. EPA removed total

chromium because the Appendix G--Section I list is limited to those

pollutants specifically regulated in part 503. Second, to ensure the

continued eligibility of chromium for a removal credit when sewage

sludge is land-applied, EPA added a footnote to the table in Appendix

G--Section II. This table lists pollutants not regulated in part 503

that are eligible for a removal credit so long as the concentration of

the pollutant in sewage sludge does not exceed the concentration for

the pollutant in the table. The footnote stated that determination of a

concentration limit for total chromium in sewage sludge that is land-

applied would be made on a case-by-case basis. Case-by-case

determinations would continue until EPA published a concentration for

total chromium in Appendix G--Section II for land-applied sewage

sludge.

EPA reviewed the part 503 land application risk assessment for

total chromium, and on October 25, 1995, proposed to establish the

concentration for total chromium for removal credit purposes in

Appendix G--Section II at 12,000 mg/kg (60 FR 54771). This is the value

determined to be protective of ground water in the part 503 land

application risk assessment. The ground-water pathway was the pathway

that resulted in the most stringent limit for total chromium after the

phytotoxicity and animal grazing pathways were found to be

inappropriate (see EPA's reanalysis of the exposure pathways for total

chromium in land-applied sewage sludge in the docket for the October

25, 1995, proposal). Several comments were received on the proposal.

One commenter stated that a numerical value for total chromium in

Appendix G--Section II for land-applied sewage sludge is not necessary

as a condition for granting a removal credit for total chromium. The

commenter believes that the Clean Water Act, as amended, provides EPA

the authority to grant a removal credit without having a numerical

value for the pollutant in Appendix G--Sections I or II. EPA disagrees

with this comment. EPA's position is that a numerical value for the

pollutant must be established in Appendix G--Sections I or II for the

POTW to be able to grant a removal credit to the indirect discharger

for that pollutant. As articulated in the preamble to EPA's recent

pretreatment streamlining rule, a POTW or industrial user can currently

petition the Agency to establish a Part 503 standard or an amendment to

Part 403, Appendix G--Section II for a pollutant along with an analysis

of the impact of the pollutant on the use or disposal of its sewage

sludge. Upon promulgation of the Part 503 standard or listing of the

pollutant in Part 403, Appendix G--Section II, the pollutant would be

eligible for inclusion in an application for a removal credit.

With respect to the numerical limit for total chromium, several

commenters took issue with some of the assumptions underlying the

proposed numeric limit in Appendix G--Section II. Specifically, the

commenters indicated that there are problems with the Agency's land

application ground-water pathway exposure assessment, which was the

basis for the proposed numerical value for total chromium in land-

applied sewage sludge in Appendix G--Section II. In the commenters'

views, the values for the land application site parameters and the

pollutant-specific parameters used in the ground-water pathway analysis

are too conservative. Moreover, the commenters believe that EPA's

assessment erroneously relied on parameters associated with chromium

[[Page 42564]]

in its hexavalent form rather than in the trivalent form.

EPA disagrees that the values for the land application site

parameters (i.e., soil type, depth to groundwater, and thickness of

aquifer) used in the ground-water pathway exposure analysis are too

conservative. Because food crops are grown in sandy soils and because

sewage sludge is applied to sandy soils, the Agency assumed sand, which

has a high pollutant transmission potential, as the soil type when

evaluating the ground-water pathway. Likewise, it is not unreasonable

to assume that there will be circumstances in which crops will be grown

on land that has a depth to groundwater of one meter. Similarly, it is

likely that in dryer climates the thickness of the aquifer below the

application site could be as small as one meter. Given the potential

for land application in such conditions, the values EPA used for the

site parameters in the ground-water pathway analysis are reasonable.

EPA agrees, however, that the numerical values for pollutant-

specific parameters used in the ground-water pathway analysis are

inappropriate for modeling either trivalent chromium or total chromium.

This is because the numerical value for the human health endpoint

(i.e., maximum contaminant level) used in the ground-water pathway

analysis is based on exposure to hexavalent chromium (see 56 FR 3537,

January 30, 1991), and because the numerical value for the partition

coefficient (KD value) used in the ground-water pathway analysis is

what would be expected for hexavalent chromium. EPA concluded,

therefore, that the 12,000 mg-chromium/kg-sewage sludge value proposed

for total chromium in Appendix G--Section II on October 25, 1995, is

for the hexavalent form of chromium in sewage sludge that is land-

applied.

Given that the 12,000 mg/kg concentration is for hexavalent

chromium only, EPA could either establish the concentration limit in

Appendix G--Section II for hexavalent chromium, or determine an

appropriate concentration for total chromium. EPA rejected the option

of setting a concentration limit for hexavalent chromium only. It is

extremely difficult to determine the concentration of hexavalent

chromium in sewage sludge for two reasons. First, it is present in

sewage sludge at very low levels relative to trivalent chromium levels.

Second, hexavalent chromium's high chemical reactivity characteristics

make it extremely difficult to quantify in analytical procedures.

Therefore, EPA concluded that the chromium limit for land-applied

sewage sludge on the list in Appendix G--Section II should be for total

chromium.

To determine a limit for total chromium, which represents a mixture

of both hexavalent and trivalent chromium, EPA had to determine

concentrations for both hexavalent chromium and trivalent chromium that

do not cause a reasonably anticipated adverse effect. As noted above,

EPA already determined that if the hexavalent chromium concentration

does not exceed 12,000 mg/kg, hexavalent chromium in sewage sludge that

is land-applied will not have an adverse effect on public health and

the environment. For trivalent chromium, formal ground-water modeling

has not been performed. Therefore, EPA derived the concentration value

for trivalent chromium for the ground-water pathway based on some

assumptions.

EPA made two assumptions in using a simple model to determine the

trivalent chromium concentration. First, the Agency assumed that all of

the values for the land application site parameters in the ground-water

model for hexavalent chromium are the same for trivalent chromium. That

is, the soil type is sand, the depth to groundwater is one meter, and

the thickness of the aquifer is one meter.

Second, EPA assumed that, with the exception of the oral reference

dose (RfD), the pollutant-specific parameters for hexavalent chromium

are the same for trivalent chromium, including the KD value of 59 l/kg.

The RfD for hexavalent chromium used to derive the human health

endpoint in the ground-water pathway is 5 x 10-3 mg/kg-day.

The RfD for trivalent chromium is 1 mg/kg-day--some 200 times greater.

Because the ratio of the numerical values for the RfDs of trivalent to

hexavalent chromium is 200, with all other land application site

parameters and pollutant-specific parameters being equal for the two

chromium valence species, the estimated allowable concentration value

for trivalent chromium in sewage sludge is 200 times the allowable

concentration for hexavalent chromium or 2,400,000 mg/kg. This is only

a theoretical value because the actual concentration can never exceed

one million milligrams per kilogram.

The above theoretical concentration for trivalent chromium is an

extremely conservative estimate based on many comments that stated that

the KD values for trivalent chromium are reported as high as several

thousand l/kg. If KD values like these are used in the analysis, the

estimated theoretical concentration for trivalent chromium would be

higher.

As indicated in the Technical Support Document for Land Application

of Sewage Sludge (EPA 822/R-93-001a, November 1992) on page 5-107,

sewage sludge contains little, if any, hexavalent chromium because

hexavalent chromium is reduced to trivalent chromium during sewage

sludge treatment. Thus, EPA believes the concentration of hexavalent

chromium in sewage sludge compared to the concentration of trivalent

chromium is negligible. At most, hexavalent chromium should not exceed

one percent (i.e., 10,000 mg/kg) of the total chromium in sewage

sludge.

EPA is today establishing the total chromium concentration in

Appendix G--Section II for land-applied sewage sludge at 100,000 mg/kg.

The Agency concluded that, although trivalent chromium is the prevalent

form of chromium in sewage sludge, it is the hexavalent form of

chromium that the total chromium concentration for land-applied sewage

sludge must limit. Two commenters recommended a concentration of

100,000 mg/kg as appropriate to protect ground water from total

chromium in land-applied sewage sludge. This concentration is

consistent with the total chromium concentration limit established for

granting a removal credit for sewage sludge placed in a lined active

sewage sludge unit. Because the percentage of hexavalent chromium in

total chromium is expected to be less than one percent, there is

virtually no potential that the hexavalent chromium concentration in

land-applied sewage sludge will exceed the allowable concentration for

hexavalent chromium (i.e, 12,000 mg/kg) in the 100,000 mg/kg total

chromium concentration limit.

A total chromium concentration of 100,000 mg/kg in land-applied

total chromium also ensures that the total chromium limit from other

pathways in the part 503 land application risk assessment is not

exceeded. For example, the total chromium limit for the animal grazing

pathway is 190,000 mg/kg, which is almost twice the total chromium

concentration in Appendix G--Section II in today's rulemaking.

Finally, it is important to note that the value for total chromium

the Agency is adopting today in Appendix G--Section II for land-applied

sewage sludge is 1-2 orders of magnitude greater than the highest

concentration of total chromium ever measured in sewage sludge based on

the results of the 1989 National Sewage Sludge Survey. This too should

ensure that the granting of a removal credit for total chromium will

not

[[Page 42565]]

adversely affect public health and environmental when sewage sludge is

applied to the land.

VII. Regulatory Requirements

A. Executive Order 12866, Regulatory Planning and Review

Under Executive Order 12866 (58 FR 51735, October 4, 1993), the

Agency must determine whether a regulatory action is ``significant''

and therefore subject to review by the Office of Management and Budget

(OMB) and the requirements of the Executive Order. The Order defines

``significant regulatory action'' as one that is likely to result in a

rule that may:

(1) Have an annual effect on the economy of $100 million or more or

adversely affect in a material way the economy, a sector of the

economy, productivity, competition, jobs, the environment, public

health or safety, or State, local, or tribal government or communities;

(2) Create a serious inconsistency or otherwise interfere with an

action taken or planned by another agency;

(3) Materially alter the budgetary impact of entitlements, grants,

user fees, or loan programs or the rights and obligations of recipients

thereof; or

(4) Raise novel legal or policy issues arising out of legal

mandates, the President's priorities, or the principles set forth in

the Executive Order.

It has been determined that this final rule is not a

``significant'' regulatory action under the terms of Executive Order

12866 and is not subject, therefore, to OMB review. Further, because

the effect of today's rule is to modify current requirements and

provide additional flexibility to the regulated community in complying

with the part 503 requirements, and to allow a removal credit for

chromium in land applied sewage sludge under part 403, costs to the

regulated community should be reduced or at least remain unchanged.

B. Regulatory Flexibility Act

Under the Regulatory Flexibility Act (RFA), 5 U.S.C. 601 et seq.,

as amended by the Small Business Regulatory Enforcement Fairness Act,

EPA generally is required to conduct a regulatory flexibility analysis

describing the impact of the regulatory action on small entities as

part of rulemaking. However, under section 605(b) of the RFA, if EPA

certifies that the rule will not have a significant economic impact on

a substantial number of small entities, EPA is not required to prepare

a regulatory flexibility analysis. Pursuant to section 605(b) of the

Regulatory Flexibility Act, 5 U.S.C. 605(b), the Administrator

certifies that this rule will not have a significant economic impact on

a substantial number of small entities.

This action to amend the part 503 regulation provides added

flexibility in complying with the part 503 requirements and technical

clarification for some of the requirements. For example, the permitting

authority has been given the discretion to reduce the frequency of

monitoring for some of the pollutants subject to the rule. Today's

action also makes the incineration requirements self-implementing by

specifying how an incinerator owner/operator is to determine pollutant

limits applicable to sewage sludge to be combusted. The incineration

amendments include requirements to provide notice to the permitting

authority prior to performance testing and to report information that

was previously obtained by the permitting authority during the

permitting process. These requirements involve minimal additional cost,

because the requirements to develop the information needed to calculate

the pollutant limits are not new. Only the need to provide prior notice

of testing and to report the results are new, and these requirements

involve little expense.

In addition, this action amends the part 403 regulation to

establish a total chromium in sewage sludge concentration to allow a

wastewater treatment works to issue a removal credit for chromium in

land applied sewage sludge. This relieves the wastewater treatment

works from having to perform a site-specific evaluation and calculation

to establish a total chromium concentration in sewage sludge in order

to issue a pre-treatment removal credit for chromium to an industrial

discharger. As such, the amendments impose no significant new

requirements on the regulated community, including small entities.

Accordingly, I certify that this regulation will not have a

significant economic impact on a substantial number of small entities.

Therefore, this final regulation does not require a regulatory

flexibility analysis.

C. Congressional Review Act

The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the

Small Business Regulatory Enforcement Fairness Act of 1996, generally

provides that before a rule may take effect, the agency promulgating

the rule must submit a rule report, which includes a copy of the rule,

to each House of the Congress and to the Comptroller General of the

United States. EPA will submit a report containing this rule and other

required information to the U.S. Senate, the U.S. House of

Representatives, and the Comptroller General of the United States prior

to publication of the rule in the Federal Register. A major rule cannot

take effect until 30 days after it is published in the Federal

Register. This rule is not a ``major rule'' as defined by 5 U.S.C.

Sec. 804(2). This rule will be effective September 3, 1999.

D. Paperwork Reduction Act

The information collection requirements for existing 40 CFR part

503 were approved by OMB under the Paperwork Reduction Act, 44 U.S.C.

3501 et seq. OMB approved the information collection requirements for

the existing regulation (part 503) and assigned OMB Control Nos. 2040-

0004 and 2040-0086. Today's action amending part 503 reduces

information collection requirements in part 503 by allowing the

permitting authority to reduce the frequency of monitoring for certain

part 503 pollutants.

However, today's action also adds a new notice requirement in

Sec. 503.43(e). The information collection request for this new

provision is currently under development. EPA expects to publish a

proposed Information Collection Request (ICR) for these requirements in

the Federal Register for comment within the next 60 days. The ICR will

be submitted for approval to the Office of Management and Budget (OMB)

under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. after public

comment. The information requirements will be published in the Federal

Register again for public comment when EPA submits them to OMB for

review and approval. An agency may not conduct or sponsor, and a person

is not required to respond to a collection of information unless it

displays a currently valid OMB control number. The OMB control numbers

for EPA's regulations are listed in 40 CFR part 9 and 48 CFR chapter

15.

E. Unfunded Mandate Reform Act

Title II of the Unfunded Mandate Reform Act of 1995 (UMRA), Public

Law 104-4, establishes requirements for Federal agencies to assess the

effects of their regulatory actions on State, local, and tribal

governments and the private sector. Under section 202 of the UMRA, EPA

generally must prepare a written statement, including a cost-benefit

analysis, for proposed and final rules with ``Federal mandates'' that

may result in expenditures to State, local, and tribal governments, in

the aggregate, or to the private sector, of $100 million or more in any

one year. Before

[[Page 42566]]

promulgating an EPA rule for which a written statement is needed,

section 205 of the UMRA generally requires EPA to identify and consider

a reasonable number of regulatory alternatives and adopt the least

costly, most cost-effective or least burdensome alternative that

achieves the objectives of the rule. The provisions of section 205 do

not apply when they are inconsistent with applicable law. Moreover,

section 205 allows EPA to adopt an alternative other than the least

costly, most cost-effective or least burdensome alternative if the

Administrator publishes with the final rule an explanation why that

alternative was not adopted.

Before EPA establishes any regulatory requirements that may

significantly or uniquely affect small governments, including tribal

governments, it must have developed under section 203 of the UMRA a

small government agency plan. The plan must provide for notifying

potentially affected small governments, enabling officials of affected

small governments to have meaningful and timely input in the

development of EPA regulatory proposals with significant Federal

intergovernmental mandates, and informing, educating, and advising

small governments on compliance with the regulatory requirements.

EPA has determined that today's amendments do not contain a Federal

mandate that may result in expenditures of $100 million or more for

State, local, and tribal governments, in the aggregate, or the private

sector in any one year. The final amendments either clarify existing

regulatory requirements or provide additional flexibility to the

regulated community in complying with current part 503 requirements and

allow for the issuance of removal credits under part 403.

For example, EPA is making a number of changes to reduce the

reporting and recordkeeping burden of the current requirements. These

include an amendment to authorize the permitting authority to reduce

the frequency of monitoring of sewage sludge for pollutants and certain

pathogen density requirements. In addition, the amendments modify the

provision to certify that compliance with certain requirements was

achieved. Under today's amendment, a person certifies to the accuracy

of the submitted information and not, as is the case at present, to

compliance with regulatory requirements.

Today's amendments also delete the language from the current

regulation that requires the permitting authority to specify certain

factors used to calculate site-specific pollutant limits for sewage

sludge incinerators and to specify how to install, calibrate, operate,

and maintain incinerator continuous emission monitors. Instead, the

rule contains the information needed by the incinerator owner/operator

to make the site-specific calculations and properly monitor emissions

of total hydrocarbons. These self-implementing provisions contain a

one-time requirement for the owner/operator to provide notice and

report calculations which were previously obtained from the permitting

authority. In addition, today's amendments contain technical changes

that correct inaccurate cross-references and add omitted reporting

dates and inadvertently omitted phrases. Therefore, to the extent that

today's final regulation reduces the costs of complying with the

current part 503 requirements and allow for the issuance of removal

credits under part 403, the final regulation will lessen the regulatory

burden on State, local, and tribal governments and the private sector.

As noted above, there are minimal costs or reduced costs associated

with the other changes in today's final amendments. Thus, today's

amendments are not subject to the requirements of sections 202 and 205

of the UMRA.

EPA has determined that today's amendments contain no regulatory

requirements that might significantly or uniquely affect small

governments. The final amendments do not significantly affect small

governments because, as explained above, the amendments provide

additional flexibility in complying with existing regulatory

requirements, provide for self-implementation, or clarify those

requirements. The final amendments also do not uniquely affect small

governments because the changes are applicable to facilities operated

by small governments to the same extent they are to other sewage sludge

preparers and users or disposers. Thus this rule is not subject to the

requirements of section 203 of UMRA.

F. Executive Order 12875, Enhancing Intergovernmental Partnerships

Under Executive Order 12875, EPA may not issue a regulation that is

not required by statute and that creates a mandate on a State, local,

or tribal government, unless the Federal government provides the funds

necessary to pay the direct compliance costs incurred by those

governments, or EPA consults with those governments. If EPA complies by

consulting, Executive Order 12875 requires EPA to provide to the Office

of Management and Budget a description of the extent of EPA's prior

consultation with representatives of affected State, local, and tribal

governments, the nature of their concerns, any written communications

from the governments, and a statement supporting the need to issue the

regulation. In addition, Executive Order 12875 requires EPA to develop

an effective process permitting elected officials and other

representatives of State, local, and tribal governments ``to provide

meaningful and timely input in the development of regulatory proposals

containing significant unfunded mandates.''

EPA has concluded that this rule will create a mandate on State,

local, and tribal governments and that the Federal government will not

provide the funds necessary to pay the direct costs incurred by the

State, local and/or tribal governments in complying with the mandate.

However, the mandate created by these amendments to parts 503 and 403

will have only a minimal impact on these governments as described in

sections VII A and E of this preamble.

In developing this rule, EPA consulted with State, local, and

tribal governments to enable them to provide meaningful and timely

input in the development of this rule. Over the past three years in the

development of this rule, EPA on numerous occasions has had

communication with State, local, and tribal governments on this rule.

EPA has solicited and received suggestions for improving its

implementation. This outreach effort culminated in the formation of a

National Biosolids (Sewage Sludge) Partnership which serves as an

accessible forum for these exchanges to take place. The representatives

of these governments have expressed their approval of this

communications process.

The concerns of these governments as this rule was developed

centered around their need to have greater flexibility in complying

with certain provisions of the original part 503 rule. EPA recognized

these governments' concerns by providing an option for the permitting

authority to allow for a reduction in the frequency of monitoring of

certain part 503 pollutants and allowing for increased flexibility in

complying with certain pathogen and vector attraction reduction

requirements in the part 503 rule. EPA's conclusion is that the

incorporation of these provisions of increased flexibility into the

part 503 rule still results in adequate protection of public health and

the environment from pollutants in land applied sewage sludge.

[[Page 42567]]

G. Executive Order 13084, Consultation and Coordination With Indian

Tribal Governments

Under Executive Order 13084, EPA may not issue a regulation that is

not required by statute, that significantly or uniquely affects the

communities of Indian tribal governments, and that imposes substantial

direct compliance costs on those communities, unless the Federal

government provides the funds necessary to pay the direct compliance

costs incurred by the tribal governments, or EPA consults with those

governments. If EPA complies by consulting, Executive Order 13084

requires EPA to provide to the Office of Management and Budget, in a

separately identified section of the preamble to the rule, a

description of the extent of EPA's prior consultation with

representatives of affected tribal governments, a summary of the nature

of their concerns, and a statement supporting the need to issue the

regulation. In addition, Executive Order 13084 requires EPA to develop

an effective process permitting elected officials and other

representatives of Indian tribal governments ``to provide meaningful

and timely input in the development of regulatory policies on matters

that significantly or uniquely affect their communities.''

Today's rule does not significantly or uniquely affect the

communities of Indian tribal governments and it does not impose

substantial direct compliance costs on them. The amendments clarify

existing part 503 requirements and provide the regulated community

additional flexibility in complying with the regulatory requirements

and make other requirements self-implementing. In addition, the

amendment to part 403 allows for the issuance of a removal credit for

chromium when sewage sludge is land applied, thereby reducing a

regulatory burden to the private sector. As explained in sections VII A

and E in this preamble, today's changes do not impose substantial

direct costs. Accordingly, the requirements of section 3(b) of

Executive Order 13084 do not apply to this rule.

H. Executive Order 13045, Protection of Children From Environmental

Health Risks and Safety Risks

Executive Order 13045 (62 FR 19885, April 23, 1997) applies to any

rule initiated after April 21, 1997, or proposed after April 21, 1998,

that: (1) Is determined to be ``economically significant'' as defined

under EO 12866, and (2) concerns an environmental health or safety risk

that EPA has reason to believe may have a disproportionate effect on

children. If the regulatory action meets both criteria, the agency must

evaluate the environmental health or safety effects of the planned rule

on children, and explain why the planned regulation is preferable to

other potentially effective and reasonably feasible alternatives

considered by the Agency.

Because this rule was proposed on October 25, 1995, it is not

subject to EO 13045. Also as explained in the section on EO 12866,

today's final rule is not an economically significant rule. In

addition, EPA does not have reason to believe that today's amendments

pose any environmental health or safety risks presenting a

disproportionate risk to children. However, EPA reviewed the impact of

this rule on children's health in light of the Agency's Policy on

Evaluating Health Risks to Children.

Today's amendments to part 503 do not alter any of the existing

part 503 pollutant limits, which are based on the results of the risk

assessments undertaken for the part 503 rule as published on February

19, 1993 (58 FR 9248). Today's amendment to part 403 establishes a

limit for total chromium in land-applied sewage sludge for the purpose

of granting a removal credit. That limit is based on the results of the

ground-water pathway analysis. A child is protected in this case

because the limit based on the ground-water pathway results is more

stringent than the limit based on the results of the child ingestion

pathway.

I. National Technology Transfer and Advancement Act

Under section 12(d) of the National Technology Transfer and

Advancement Act (``NTTAA''), the Agency is required to use voluntary

consensus standards in its regulatory activities unless to do so would

be inconsistent with applicable law or otherwise impractical. Voluntary

consensus standards are technical standards (e.g., materials

specifications, test methods, sampling procedures, business practices,

etc.) that are developed or adopted by voluntary consensus standards

bodies. Where available and potentially applicable voluntary concensus

standards are not used by EPA, the Act requires the Agency to provide

Congress, through OMB, an explanation of the reasons for not using such

standards.

Today's final rule does not involve technical standards. Therefore,

EPA did not consider the use of any voluntary consensus standards.

List of Subjects

40 CFR Part 403

Environmental protection, Incineration, Land application,

Pollutants, Removal credits, Sewage sludge, Surface disposal.

40 CFR Part 503

Environmental protection, Frequency of monitoring, Incineration,

Land application, Management practices, Pathogens, Pollutants,

Reporting and recordkeeping requirements, Surface disposal, Vector

attraction reduction.

Dated: July 15, 1999.

Carol M. Browner,

Administrator.

For the reasons set out in the preamble, title 40 of the Code of

Federal Regulations is amended as set forth below:

PART 403--GENERAL PRETREATMENT REGULATIONS FOR EXISTING AND NEW

SOURCES OF POLLUTION

1. The authority citation for part 403 continues to read as

follows:

Authority: 33 U.S.C. 1251 et seq.

2. Appendix G to part 403 is amended by revising section II to read

as follows:

Appendix G to Part 403--Pollutants Eligible for a Removal Credit

* * * * *

II. Additional Pollutants Eligible for a Removal Credit

[Milligrams per kilogram--dry weight basis]

----------------------------------------------------------------------------------------------------------------

Use or disposal practice

-------------------------------------------------------

Pollutant Surface disposal

LA -------------------------------- I

Unlined \1\ Lined \2\

----------------------------------------------------------------------------------------------------------------

Arsenic................................................. ............ .............. \3\ 100 ........

[[Page 42568]]

Aldrin/Dieldrin (Total)................................. 2.7 .............. .............. ........

Benzene................................................. \3\ 16 140 3400 ........

Benzo(a)pyrene.......................................... 15 \3\ 100 \3\ 100 ........

Bis(2-ethylhexyl)phthalate.............................. ............ \3\ 100 \3\ 100 ........

Cadmium................................................. ............ \3\ 100 \3\ 100 ........

Chlordane............................................... 86 \3\ 100 \3\ 100 ........

Chromium (total)........................................ \3\ 100 .............. \3\ 100 ........

Copper.................................................. ............ \3\ 46 100 1400

DDD, DDE, DDT (Total)................................... 1.2 2000 2000 ........

2,4 Dichlorophenoxy-acetic acid......................... ............ 7 7 ........

Fluoride................................................ 730 .............. .............. ........

Heptachlor.............................................. 7.4 .............. .............. ........

Hexachlorobenzene....................................... 29 .............. .............. ........

Hexachlorobutadiene..................................... 600 .............. .............. ........

Iron.................................................... \3\ 78 .............. .............. ........

Lead.................................................... ............ \3\ 100 \3\ 100 ........

Lindane................................................. 84 \3\ 28 \3\ 28 ........

Malathion............................................... ............ 0.63 0.63 ........

Mercury................................................. ............ \3\ 100 \3\ 100 ........

Molybdenum.............................................. ............ 40 40 ........

Nickel.................................................. ............ .............. \3\ 100 ........

N-Nitrosodimethylamine.................................. 2.1 0.088 0.088 ........

Pentachlorophenol....................................... 30 .............. .............. ........

Phenol.................................................. ............ 82 82 ........

Polychlorinated biphenyls............................... 4.6 <50 <50 ........

Selenium................................................ ............ 4.8 4.8 4.8

Toxaphene............................................... 10 \3\ 26 \3\ 26 ........

Trichloroethylene....................................... \3\ 10 9500 \3\ 10 ........

Zinc.................................................... ............ 4500 4500 4500

----------------------------------------------------------------------------------------------------------------

\1\ Active sewage sludge unit without a liner and leachate collection system.

\2\ Active sewage sludge unit with a liner and leachate collection system.

\3\ Value expressed in grams per kilogram--dry weight basis.

Key: LA--land application.

I--incineration.

PART 503--STANDARDS FOR THE USE OR DISPOSAL OF SEWAGE SLUDGE

1. The authority citation for part 503 continues to read as

follows:

Authority: Sections 405(d) and (e) of the Clean Water Act, as

amended by Pub. L. 95-217, Sec. 54(d), 91 Stat. 1591 (33 U.S.C. 1345

(d) and (e)); and Pub. L. 100-4, Title IV, Sec. 406(a), (b), 101

Stat., 71, 72 (33 U.S.C. 1251 et seq.)

2. Section 503.2 is amended by adding a new paragraph (d) to read

as follows:

Sec. 503.2 Compliance period.

* * * * *

(d) Unless otherwise specified in subpart E, compliance with the

requirements in Secs. 503.41(c) through (r), 503.43(c), (d) and (e),

503.45(a)(1), (b) through (f), 503.46(a)(1), (a)(3), and (c), and

503.47(f) that were revised on September 3, 1999 shall be achieved as

expeditiously as practicable, but in no case later than September 5,

2000. When new pollution control facilities must be constructed to

comply with the revised requirements in subpart E, compliance with the

revised requirements shall be achieved as expeditiously as practicable

but no later than September 4, 2001.

3. Section 503.10 is amended by revising paragraphs (b)(1), (c)(1),

(d), (e), (f), and (g) to read as follows:

Sec. 503.10 Applicability.

* * * * *

(b)(1) Bulk sewage sludge. The general requirements in Sec. 503.12

and the management practices in Sec. 503.14 do not apply when bulk

sewage sludge is applied to the land if the bulk sewage sludge meets

the ceiling concentrations in Table 1 of Sec. 503.13 and the pollutant

concentrations in Table 3 of Sec. 503.13; the Class A pathogen

requirements in Sec. 503.32(a); and one of the vector attraction

reduction requirements in Sec. 503.33(b)(1) through (b)(8).

* * * * *

(c)(1) The general requirements in Sec. 503.12 and the management

practices in Sec. 503.14 do not apply when a bulk material derived from

sewage sludge is applied to the land if the derived bulk material meets

the ceiling concentrations in Table 1 of Sec. 503.13 and the pollutant

concentrations in Table 3 of Sec. 503.13; the Class A pathogen

requirements in Sec. 503.32(a); and one of the vector attraction

reduction requirements in Sec. 503.33(b)(1) through (b)(8).

* * * * *

(d) The requirements in this subpart do not apply when a bulk

material derived from sewage sludge is applied to the land if the

sewage sludge from which the bulk material is derived meets the ceiling

concentrations in Table 1 of Sec. 503.13 and the pollutant

concentrations in Table 3 of Sec. 503.13; the Class A pathogen

requirements in Sec. 503.32(a); and one of the vector attraction

reduction requirements in Sec. 503.33(b)(1) through (b)(8).

(e) Sewage sludge sold or given away in a bag or other container

for

[[Page 42569]]

application to the land. The general requirements in Sec. 503.12 and

the management practices in Sec. 503.14 do not apply when sewage sludge

is sold or given away in a bag or other container for application to

the land if the sewage sludge sold or given away in a bag or other

container for application to the land meets the ceiling concentrations

in Table 1 of Sec. 503.13 and the pollutant concentrations in Table 3

of Sec. 503.13; the Class A pathogen requirements in Sec. 503.32(a);

and one of the vector attraction reduction requirements in

Sec. 503.33(b)(1) through (b)(8).

(f) The general requirements in Sec. 503.12 and the management

practices in Sec. 503.14 do not apply when a material derived from

sewage sludge is sold or given away in a bag or other container for

application to the land if the derived material meets the ceiling

concentrations in Table 1 of Sec. 503.13 and the pollutant

concentrations in Table 3 of Sec. 503.13; the Class A pathogen

requirements in Sec. 503.32(a); and one of the vector attraction

reduction requirements in Sec. 503.33(b)(1) through (b)(8).

(g) The requirements in this subpart do not apply when a material

derived from sewage sludge is sold or given away in a bag or other

container for application to the land if the sewage sludge from which

the material is derived meets the ceiling concentrations in Table 1 of

Sec. 503.13 and the pollutant concentrations in Table 3 of Sec. 503.13;

the Class A pathogen requirements in Sec. 503.32(a); and one of the

vector attraction reduction requirements in Sec. 503.33 (b)(1) through

(b)(8).

4. Section 503.16 is amended by revising paragraphs (a)(1) and

(a)(2) to read as follows:

Sec. 503.16 Frequency of monitoring.

(a) Sewage sludge. (1) The frequency of monitoring for the

pollutants listed in Table 1, Table 2, Table 3 and Table 4 of

Sec. 503.13; the pathogen density requirements in Sec. 503.32(a) and

Sec. 503.32(b)(2); and the vector attraction reduction requirements in

Sec. 503.33 (b)(1) through (b)(4) and Sec. 503.33 (b)(7) through (b)(8)

shall be the frequency in Table 1 of Sec. 503.16.

Table 1 of Sec. 503.16--Frequency of Monitoring--Land Application

----------------------------------------------------------------------------------------------------------------

Amount of sewage sludge \1\ (metric tons

per 365 day period) Frequency

----------------------------------------------------------------------------------------------------------------

Greater than zero but less than 290........ Once per year.

Equal to or greater than 290 but less than Once per quarter (four times per year).

1,500.

Equal to or greater than 1,500 but less Once per 60 days (six times per year).

than 15,000.

Equal to or greater than 15,000............ Once per month (12 times per year).

----------------------------------------------------------------------------------------------------------------

\1\ Either the amount of bulk sewage sludge applied to the land or the amount of sewage sludge prepared for sale

or give-away in a bag or other container for application to the land (dry weight basis).

(2) After the sewage sludge has been monitored for two years at the

frequency in Table 1 of Sec. 503.16, the permitting authority may

reduce the frequency of monitoring for pollutant concentrations and for

the pathogen density requirements in Sec. 503.32(a)(5)(ii) and

(a)(5)(iii).

* * * * *

5. Section 503.17 is amended by revising paragraphs (a)(1)(ii),

(a)(2)(ii), (a)(3)(i)(B), (a)(3)(ii)(A), (a)(4)(i)(B), (a)(4)(ii)(A),

(a)(5)(i)(B), (a)(5)(ii)(C), (a)(5)(ii)(F), (a)(5)(ii)(H),

(a)(5)(ii)(J), (a)(5)(ii)(L), (a)(6)(iii), (b)(3), (b)(6), and (b)(7),

and by adding a new paragraph (a)(4)(ii)(E) to read as follows:

Sec. 503.17 Recordkeeping.

(a) Sewage sludge. (1) * * *

(ii) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine compliance with the Class A pathogen

requirements in Sec. 503.32(a) and the vector attraction reduction

requirement in [insert one of the vector attraction reduction

requirements in Sec. 503.33(b)(1) through Sec. 503.33(b)(8)] was

prepared under my direction and supervision in accordance with the

system designed to ensure that qualified personnel properly gather

and evaluate this information. I am aware that there are significant

penalties for false certification including the possibility of fine

and imprisonment.

* * * * *

(2) * * *

(ii) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine compliance with the Class A pathogen

requirements in Sec. 503.32(a) and the vector attraction reduction

requirement in (insert one of the vector attraction reduction

requirements in Sec. 503.33(b)(1) through (b)(8)) was prepared under

my direction and supervision in accordance with the system designed

to ensure that qualified personnel properly gather and evaluate this

information. I am aware that there are significant penalties for

false certification including the possibility of fine and

imprisonment.

* * * * *

(3) * * *

(i) * * *

(B) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine compliance with the Class A pathogen

requirements in Sec. 503.32(a) was prepared under my direction and

supervision in accordance with the system designed to ensure that

qualified personnel properly gather and evaluate this information. I

am aware that there are significant penalties for false

certification including the possibility of fine and imprisonment.

* * * * *

(ii) * * *

(A) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine compliance with the management practices in

Sec. 503.14 and the vector attraction reduction requirement in

(insert either Sec. 503.33(b)(9) or (b)(10)) was prepared under my

direction and supervision in accordance with the system designed to

ensure that qualified personnel properly gather and evaluate this

information. I am aware that there are significant penalties for

false certification including the possibility of fine and

imprisonment.

* * * * *

(4) * * *

(i) * * *

(B) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine compliance with the Class B pathogen

requirements in Sec. 503.32(b) and the vector attraction reduction

requirement in (insert one of the vector attraction reduction

requirements in Sec. 503.33(b)(1) through (b)(8)if one of those

requirements is met) was prepared under my direction and supervision

in accordance with the system designed to ensure that qualified

personnel properly gather and evaluate this information. I am aware

that there are significant penalties for false certification

including the possibility of fine and imprisonment.

* * * * *

(ii) * * *

(A) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine

[[Page 42570]]

compliance with the management practices in Sec. 503.14, the site

restrictions in Sec. 503.32(b)(5), and the vector attraction

reduction requirement in (insert either Sec. 503.33(b)(9) or (b)(10)

if one of those requirements is met) was prepared for each site on

which bulk sewage sludge is applied under my direction and

supervision in accordance with the system designed to ensure that

qualified personnel properly gather and evaluate this information. I

am aware that there are significant penalties for false

certification including the possibility of fine and imprisonment.

* * * * *

(E) The date bulk sewage sludge is applied to each site.

(5) * * *

(i) * * *

(B) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine compliance with the pathogen requirements in

(insert either Sec. 503.32(a) or Sec. 503.32(b)) and the vector

attraction reduction requirement in (insert one of the vector

attraction reduction requirements in Sec. 503.33(b)(1) through

(b)(8) if one of those requirements is met) was prepared under my

direction and supervision in accordance with the system designed to

ensure that qualified personnel properly gather and evaluate this

information. I am aware that there are significant penalties for

false certification including the possibility of fine and

imprisonment.

* * * * *

(ii) * * *

(C) The date bulk sewage sludge is applied to each site.

* * * * *

(F) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine compliance with the requirement to obtain

information in Sec. 503.12(e)(2) was prepared for each site on which

bulk sewage sludge was applied under my direction and supervision in

accordance with the system designed to ensure that qualified

personnel properly gather and evaluate this information. I am aware

that there are significant penalties for false certification

including the possibility of fine and imprisonment.

* * * * *

(H) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine compliance with the management practices in

Sec. 503.14 was prepared for each site on which bulk sewage sludge

was applied under my direction and supervision in accordance with

the system designed to ensure that qualified personnel properly

gather and evaluate this information. I am aware that there are

significant penalties for false certification including the

possibility of fine and imprisonment.

* * * * *

(J) The following certification statement when the bulk sewage

sludge meets the Class B pathogen requirements in Sec. 503.32(b):

I certify, under penalty of law, that the information that will

be used to determine compliance with the site restrictions in

Sec. 503.32(b)(5) for each site on which Class B sewage sludge was

applied was prepared under my direction and supervision in

accordance with the system designed to ensure that qualified

personnel properly gather and evaluate this information. I am aware

that there are significant penalties for false certification

including the possibility of fine and imprisonment.

* * * * *

(L) The following certification statement when the vector

attraction reduction requirement in either Sec. 503.33(b)(9) or (b)(10)

is met:

I certify, under penalty of law, that the information that will

be used to determine compliance with the vector attraction reduction

requirement in (insert either Sec. 503.33(b)(9) or

Sec. 503.33(b)(10)) was prepared under my direction and supervision

in accordance with the system designed to ensure that qualified

personnel properly gather and evaluate this information. I am aware

that there are significant penalties for false certification

including the possibility of fine and imprisonment.

* * * * *

(6) * * *

(iii) The following certification statement:

I certify, under penalty of law, that the information that will be

used to determine compliance with the management practice in

Sec. 503.14(e), the Class A pathogen requirement in Sec. 503.32(a), and

the vector attraction reduction requirement in (insert one of the

vector attraction reduction requirements in Sec. 503.33(b)(1) through

Sec. 503.33(b)(8)) was prepared under my direction and supervision in

accordance with the system designed to ensure that qualified personnel

properly gather and evaluate this information. I am aware that there

are significant penalties for false certification including the

possibility of fine and imprisonment.

* * * * *

(b) * * *

(3) The date domestic septage is applied to each site.

* * * * *

(6) The following certification statement:

I certify, under penalty of law, that the information that will be

used to determine compliance with the pathogen requirements (insert

either Sec. 503.32(c)(1) or Sec. 503.32(c)(2)) and the vector

attraction reduction requirement in [insert Sec. 503.33(b)(9),

503.33(b)(10), or Sec. 503.33(b)(12)] was prepared under my direction

and supervision in accordance with the system designed to ensure that

qualified personnel properly gather and evaluate this information. I am

aware that there are significant penalties for false certification

including the possibility of fine and imprisonment.

(7) A description of how the pathogen requirements in either

Sec. 503.32(c)(1) or (c)(2) are met.

* * * * *

6. Section 503.18 is amended by revising paragraph (a)(2) to read

as follows:

Sec. 503.18 Reporting.

(a) * * *

(2) The information in Sec. 503.17(a)(5)(ii)(A) through

(a)(5)(ii)(G) on February 19th of each year when 90 percent or more of

any of the cumulative pollutant loading rates in Table 2 of Sec. 503.13

is reached at a land application site.

* * * * *

7. Section 503.21 is amended by revising paragraph (c) to read as

follows:

Sec. 503.21 Special definitions.

* * * * *

(c) Contaminate an aquifer means to introduce a substance that

causes the maximum contaminant level for nitrate in 40 CFR 141.62(b) to

be exceeded in the ground water or that causes the existing

concentration of nitrate in ground water to increase when the existing

concentration of nitrate in the ground water exceeds the maximum

contaminant level for nitrate in 40 CFR 141.62(b).

* * * * *

8. Section 503.22 is amended by revising paragraph (b) to read as

follows:

Sec. 503.22 General requirements.

* * * * *

(b) An active sewage sludge unit located within 60 meters of a

fault that has displacement in Holocene time; located in an unstable

area; or located in a wetland, except as provided in a permit issued

pursuant to either section 402 or 404 of the CWA, shall close by March

22, 1994, unless, in the case of an active sewage sludge unit located

within 60 meters of a fault that has displacement in Holocene time,

otherwise specified by the permitting authority.

* * * * *

9. Section 503.26 is amended by revising paragraphs (a)(1) and

(a)(2) to read as follows:

Sec. 503.26 Frequency of monitoring.

(a) Sewage sludge (other than domestic septage). (1) The frequency

of

[[Page 42571]]

monitoring for the pollutants in Tables 1 and 2 of Sec. 503.23; the

pathogen density requirements in Sec. 503.32(a) and in

Sec. 503.32(b)(2); and the vector attraction reduction requirements in

Sec. 503.33(b)(1) through (b)(4) and Sec. 503.33(b)(7) through (b)(8)

for sewage sludge placed on an active sewage sludge unit shall be the

frequency in Table 1 of Sec. 503.26.

Table 1 of Sec. 503.26.--Frequency of Monitoring--Surface Disposal

----------------------------------------------------------------------------------------------------------------

Amount of sewage sludge \1\ (metric tons

per 365 day period) Frequency

----------------------------------------------------------------------------------------------------------------

Greater than zero but less than 290........ Once per year.

Equal to or greater than 290 but less than Once per quarter (four times per year).

1,500.

Equal to or greater than 1,500 but less Once per 60 days (six times per year).

than 15,000.

Equal to or greater than 15,000............ Once per month (12 times per year).

----------------------------------------------------------------------------------------------------------------

\1\ Amount of sewage sludge placed on an active sewage sludge unit (dry weight basis).

(2) After the sewage sludge has been monitored for two years at the

frequency in Table 1 of this section, the permitting authority may

reduce the frequency of monitoring for pollutant concentrations and for

the pathogen density requirements in Sec. 503.32(a)(5)(ii) and

(a)(5)(iii).

* * * * *

10. Section 503.27 is amended by revising paragraphs (a)(1)(ii),

(a)(2)(ii), (b)(1)(i), and (b)(2)(i) to read as follows:

Sec. 503.27 Recordkeeping.

(a) * * *

(1) * * *

(ii) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine compliance with the pathogen requirements in

(insert Sec. 503.32(a), Sec. 503.32(b)(2), Sec. 503.32(b)(3), or

Sec. 503.32(b)(4) when one of those requirements is met) and the

vector attraction reduction requirement in (insert one of the vector

attraction reduction requirements in Sec. 503.33 (b)(1) through

(b)(8) if one of those requirements is met) was prepared under my

direction and supervision in accordance with the system designed to

ensure that qualified personnel properly gather and evaluate this

information. I am aware that there are significant penalties for

false certification including the possibility of fine and

imprisonment.

* * * * *

(2) * * *

(ii) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine compliance with the management practices in

Sec. 503.24 and the vector attraction reduction requirement in

(insert one of the requirements in Sec. 503.33(b)(9) through

Sec. 503.33(b)(11) if one of those requirements is met) was prepared

under my direction and supervision in accordance with the system

designed to ensure that qualified personnel properly gather and

evaluate this information. I am aware that there are significant

penalties for false certification including the possibility of fine

and imprisonment.''

* * * * *

(b) * * *

(1) * * *

(i) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine compliance with the vector attraction reduction

requirements in Sec. 503.33(b)(12) was prepared under my direction

and supervision in accordance with the system designed to ensure

that qualified personnel properly gather and evaluate this

information. I am aware that there are significant penalties for

false certification including the possibility of fine and

imprisonment.

* * * * *

(2) * * *

(i) The following certification statement:

I certify, under penalty of law, that the information that will

be used to determine compliance with the management practices in

Sec. 503.24 and the vector attraction reduction requirements in

(insert Sec. 503.33(b)(9) through Sec. 503.33(b)(11) if one of those

requirements is met) was prepared under my direction and supervision

in accordance with the system designed to ensure that qualified

personnel properly gather and evaluate this information. I am aware

that there are significant penalties for false certification

including the possibility of fine or imprisonment.

* * * * *

11. Section 503.31 is amended by revising paragraph (g) to read as

follows:

Sec. 503.31 Special definitions.

* * * * *

(g) pH means the logarithm of the reciprocal of the hydrogen ion

concentration measured at 25 deg. Centigrade or measured at another

temperature and then converted to an equivalent value at 25 deg.

Centigrade.

* * * * *

12. Section 503.32 is amended by revising paragraphs (b)(2)(i) and

(b)(5)(v) to read as follows:

Sec. 503.32 Pathogens.

* * * * *

(b) * * *

(2) * * *

(i) Seven representative samples of the sewage sludge that is used

or disposed shall be collected.

* * * * *

(5) * * *

(v) Animals shall not be grazed on the land for 30 days after

application of sewage sludge.

* * * * *

13. Section 503.33 is amended by revising paragraph (b)(10)(i) to

read as follows:

Sec. 503.33 Vector attraction reduction.

* * * * *

(b) * * *

(10)(i) Sewage sludge applied to the land surface or placed on an

active sewage sludge unit shall be incorporated into the soil within

six hours after application to or placement on the land, unless

otherwise specified by the permitting authority.

* * * * *

14. Section 503.41 is amended by redesignating paragraphs (c), (d),

(e) (f), (g), (h), (i),(j), (k), (l), (m), (n), and (o) as paragraphs

(d), (e), (f), (g), (h), (j), (l), (m), (n), (o), (p), (q), and (r),

respectively, and by adding new paragraphs (c), (i), and (k) to read as

follows:

Sec. 503.41 Special definitions.

* * * * *

(c) Average daily concentration is the arithmetic mean of the

concentration of a pollutant in milligrams per kilogram of sewage

sludge (dry weight basis) in the samples collected and analyzed in a

month.

(i) Incinerator operating combustion temperature is the arithmetic

mean of the temperature readings in the hottest zone of the furnace

recorded in a day (24 hours) when the temperature is averaged and

recorded at least hourly during the hours the incinerator operates in a

day.

(k) Performance test combustion temperature is the arithmetic mean

of

[[Page 42572]]

the average combustion temperature in the hottest zone of the furnace

for each of the runs in a performance test.

15. Section 503.43 is amended by revising paragraphs (c) and (d),

and by adding a new paragraph (e) to read as follows:

Sec. 503.43 Pollutant limits.

* * * * *

(c) Pollutant limit--lead. (1) The average daily concentration for

lead in sewage sludge fed to a sewage sludge incinerator shall not

exceed the concentration calculated using Equation (4).

[GRAPHIC] [TIFF OMITTED] TR04AU99.048

Where:

C = Average daily concentration of lead in sewage sludge.

NAAQS = National Ambient Air Quality Standard for lead in micrograms

per cubic meter.

DF = Dispersion factor in micrograms per cubic meter per gram per

second.

CE = Sewage sludge incinerator control efficiency for lead in

hundredths.

SF = Sewage sludge feed rate in metric tons per day (dry weight basis).

(2) The dispersion factor (DF) in equation (4) shall be determined

from an air dispersion model in accordance with Sec. 503.43(e).

(i) When the sewage sludge stack height is 65 meters or less, the

actual sewage sludge incinerator stack height shall be used in the air

dispersion model to determine the dispersion factor (DF) for equation

(4).

(ii) When the sewage sludge incinerator stack height exceeds 65

meters, the creditable stack height shall be determined in accordance

with 40 CFR 51.100(ii) and the creditable stack height shall be used in

the air dispersion model to determine the dispersion factor (DF) for

equation (4).

(3) The control efficiency (CE) for equation (4) shall be

determined from a performance test of the sewage sludge incinerator in

accordance with Sec. 503.43(e).

(d) Pollutant limit--arsenic, cadmium, chromium, and nickel. (1)

The average daily concentration for arsenic, cadmium, chromium, and

nickel in sewage sludge fed to a sewage sludge incinerator each shall

not exceed the concentration calculated using equation (5).

[GRAPHIC] [TIFF OMITTED] TR04AU99.049

Where:

C = Average daily concentration of arsenic, cadmium, chromium, or

nickel in sewage sludge.

CE = Sewage sludge incinerator control efficiency for arsenic, cadmium,

chromium, or nickel in hundredths.

DF = Dispersion factor in micrograms per cubic meter per gram per

second.

RSC = Risk specific concentration for arsenic, cadmium, chromium, or

nickel in micrograms per cubic meter.

SF = Sewage sludge feed rate in metric tons per day (dry weight basis).

(2) The risk specific concentrations for arsenic, cadmium, and

nickel used in equation (5) shall be obtained from Table 1 of

Sec. 503.43.

Table 1 of Sec. 503.43.--Risk Specific Concentration for Arsenic,

Cadmium, and Nickel

------------------------------------------------------------------------

Risk specific

concentration

Pollutant (micrograms

per cubic

meter)

------------------------------------------------------------------------

Arsenic.................................................. 0.023

Cadmium.................................................. 0.057

Nickel................................................... 2.0

------------------------------------------------------------------------

(3) The risk specific concentration for chromium used in equation

(5) shall be obtained from Table 2 of Sec. 503.43 or shall be

calculated using equation (6).

Table 2 of Sec. 503.43.--Risk Specific Concentration For Chromium

------------------------------------------------------------------------

Risk specific

concentration

Type of Incinerator (micrograms

per cubic

meter)

------------------------------------------------------------------------

Fluidized bed with wet scrubber.......................... 0.65

Fluidized bed with wet scrubber and wet electrostatic 0.23

precipitator............................................

Other types with wet scrubber............................ 0.064

Other types with wet scrubber and wet electrostatic 0.016

precipitator............................................

------------------------------------------------------------------------

[GRAPHIC] [TIFF OMITTED] TR04AU99.050

Where:

RSC=risk specific concentration for chromium in micrograms per cubic

meter used in equation (5).

r=decimal fraction of the hexavalent chromium concentration in the

total chromium concentration measured in the exit gas from the sewage

sludge incinerator stack in hundredths.

(4) The dispersion factor (DF) in equation (5) shall be determined

from an air dispersion model in accordance with Sec. 503.43(e).

(i) When the sewage sludge incinerator stack height is equal to or

less than 65 meters, the actual sewage sludge incinerator stack height

shall be used in the air dispersion model to determine the dispersion

factor (DF) for equation (5).

(ii) When the sewage sludge incinerator stack height is greater

than 65 meters, the creditable stack height shall be determined in

accordance with 40 CFR 51.100(ii) and the creditable stack height shall

be used in the air dispersion model to determine the dispersion factor

(DF) for equation (5).

(5) The control efficiency (CE) for equation (5) shall be

determined from a performance test of the sewage sludge incinerator in

accordance with Sec. 503.43(e).

(e) Air dispersion modeling and performance testing. (1) The air

dispersion model used to determine the dispersion factor in Sec. 503.43

(c)(2) and (d)(4) shall be appropriate for the geographical, physical,

and population characteristics at the sewage sludge incinerator site.

The performance test used to determine the control efficiencies in

Sec. 503.43 (c)(3) and (d)(5) shall be appropriate for the type of

sewage sludge incinerator.

(2) For air dispersion modeling initiated after September 3, 1999,

the modeling results shall be submitted to the permitting authority 30

days after completion of the modeling. In addition to the modeling

results, the submission shall include a description of the air

dispersion model and the values used for the model parameters.

(3) The following procedures, at a minimum, shall apply in

conducting performance tests to determine the control efficiencies in

Sec. 503.43(c)(3) and (d)(5) after September 3, 1999:

(i) The performance test shall be conducted under representative

sewage sludge incinerator conditions at the highest expected sewage

sludge feed rate within the design capacity of the sewage sludge

incinerator.

(ii) The permitting authority shall be notified at least 30 days

prior to any performance test so the permitting authority may have the

opportunity to observe the test. The notice shall include a test

protocol with incinerator operating conditions and a list of test

methods to be used.

(iii) Each performance test shall consist of three separate runs

using the applicable test method. The control efficiency for a

pollutant shall be the arithmetic mean of the control

[[Page 42573]]

efficiencies for the pollutant from the three runs.

(4) The pollutant limits in Sec. 503.43 (c) and (d) of this section

shall be submitted to the permitting authority no later than 30 days

after completion of the air dispersion modeling and performance test.

(5) Significant changes in geographic or physical characteristics

at the incinerator site or in incinerator operating conditions require

new air dispersion modeling or performance testing to determine a new

dispersion factor or a new control efficiency that will be used to

calculate revised pollutant limits.

16. Section 503.45 is amended by revising paragraphs (a)(1), (b),

(c), (d), (e), and (f), and by adding a new paragraph (h) to read as

follows:

Sec. 503.45 Management practices.

(a)(1) An instrument that continuously measures and records the

total hydrocarbons concentration in the sewage sludge incinerator stack

exit gas shall be installed, calibrated, operated, and maintained for a

sewage sludge incinerator.

* * * * *

(b) An instrument that continuously measures and records the oxygen

concentration in the sewage sludge incinerator stack exit gas shall be

installed, calibrated, operated, and maintained for a sewage sludge

incinerator.

(c) An instrument that continuously measures and records

information used to determine the moisture content in the sewage sludge

incinerator stack exit gas shall be installed, calibrated, operated,

and maintained for a sewage sludge incinerator.

(d) An instrument that continuously measures and records combustion

temperatures shall be installed, calibrated, operated, and maintained

for a sewage sludge incinerator.

(e) Operation of a sewage sludge incinerator shall not cause the

operating combustion temperature for the sewage sludge incinerator to

exceed the performance test combustion temperature by more than 20

percent.

(f) An air pollution control device shall be appropriate for the

type of sewage sludge incinerator and the operating parameters for the

air pollution control device shall be adequate to indicate proper

performance of the air pollution control device. For sewage sludge

incinerators subject to the requirements in subpart O of 40 CFR part

60, operation of the air pollution control device shall not violate the

requirements for the air pollution control device in subpart O of 40

CFR part 60. For all other sewage sludge incinerators, operation of the

air pollution control device shall not cause a significant exceedance

of the average value for the air pollution control device operating

parameters from the performance test required by Sec. 503.43 (c)(3) and

(d)(5).

* * * * *

(h) The instruments required in Sec. 503.45(a)-(d) shall be

appropriate for the type of sewage sludge incinerator.

17. Section 503.46 is amended by revising paragraphs (a)(1),

(a)(3), and (c) to read as follows:

Sec. 503.46 Frequency of monitoring.

(a) Sewage sludge.

(1) The frequency of monitoring for beryllium shall be as required

in subpart C of 40 CFR part 61, and for mercury as required in subpart

E of 40 CFR part 61.

* * * * *

(3) After the sewage sludge has been monitored for two years at the

frequency in Table 1 of Sec. 503.46, the permitting authority may

reduce the frequency of monitoring for arsenic, cadmium, chromium,

lead, and nickel.

* * * * *

(c) Air pollution control device operating parameters.

For sewage sludge incinerators subject to the requirements in

subpart O of 40 CFR part 60, the frequency of monitoring for the

appropriate air pollution control device operating parameters shall be

the frequency of monitoring in subpart O of 40 CFR part 60. For all

other sewage sludge incinerators, the appropriate air pollution control

device operating parameters shall be at least daily.

18. Section 503.47 is amended by revising paragraph (f) to read as

follows:

Sec. 503.47 Recordkeeping.

* * * * *

(f) The operating combustion temperatures for the sewage sludge

incinerator.

* * * * *

19. Appendix B to 40 CFR part 503 is amended by revising the

description No. 6 under B. Processes to Further Reduce Pathogens (PFRP)

to read as follows:

Appendix B to Part 503--Pathogen Treatment Processes

* * * * *

B. * * *

(6) Gamma ray irradiation--Sewage sludge is irradiated with

gamma rays from certain isotopes, such as \60\ Cobalt and \137\

Cesium, at dosages of at least 1.0 megarad at room temperature (ca.

20 deg. Celsius).

* * * * *

[FR Doc. 99-18604 Filed 8-3-99; 8:45 am]

BILLING CODE 6560-50-P