Sewage Sludge Utilization In Maryland

Land Management Administration

Sewage Sludge Utilization Section

www.mde.maryland.gov

Laws and Regulations

• Sewage sludge has been regulated in Maryland since 1974

• Annotated Code of Maryland, Environment Article,

– §§ 9-230-249, 269, and 270

• Code of Maryland Regulations

– COMAR 26.04.06

• New regulations effective May 26, 2014

• A site specific permit must be issued prior to sewage sludge utilization

• Sewage sludge is not raw sewage. It is one of

the final products of the treatment of municipal

wastewater at a wastewater treatment plant.

• After treatment breaks down the organic

compounds and kills disease–causing

organisms, the remaining fine particles

ultimately become sewage sludge which is a

nutrient-rich organic product.

• Further treatment of sewage sludge is required

in order to be land applied.

What Is Sewage Sludge?

How is Sewage Sludge Regulated?

• At the wastewater treatment plant

• Through a site specific permit

• Compliance and Enforcement

• Recordkeeping and reporting

Treatment Requirements

• For land application, at a minimum, sewage sludge must meet Class B standards as defined by EPA’s 40 CFR Part 503

• Sewage sludge sources are permitted for land application

– Review of historical sewage sludge analysis

– Review and monitoring of the treatment method

– Facility inspections

– On-going monitoring of nutrients, metals, and PCBs content

– Record keeping and annual reporting

• 38 Class B sources currently approved

Treatment Requirements

• Constituent Limits

– Arsenic, Cadmium, Copper, Lead, Mercury, Nickel, Selenium, Zinc, PCBs

• Pathogen Reduction

– Class A – pathogens are below detectable limits

– Class B – pathogens are detectable but reduced to levels that do not pose a threat to public health and the environment with proper controls.

• Vector Attraction Reduction

– Vectors are organisms, such as rodents and insects, that can spread disease by carrying and transferring pathogens

Treatment Requirements

• Sewage sludge land applied for agricultural sites must meet

constituent limits.

– Table 1 — Ceiling Concentrations (milligrams per kilogram)

– Table 2 — Cumulative Constituent Loading Rates (kilograms per

hectare)

– Table 3 — Constituent Concentrations - Monthly Average

Concentration (milligrams per kilogram)

– Table 4 — Annual Constituent Loading Rates (kilograms per

hectare per 365 day period)

• Bulk sewage sludge applied to an agricultural site must have

no constituents that exceed Table 1 limits, and must meet

either Table 2 or Table 3 limits.

Pathogen Destruction• Class B (Three Alternatives)

– Monitoring of Indicator Organisms

– Use of PSRP (Process to Significantly Reduce Pathogens)

– Use of a Process Equivalent to PRSP

• Class A (Six Alternatives)

– Thermally Treated Biosolids

– Biosolids Treated in a High pH-High Temperature Process

– For Biosolids Treated in Other Processes

– Biosolids Treated in Unknown Processes

– Use of a PFRP (Process of Further Reduce Pathogens)

– Use of a Process Equivalent to PFRP

PSRP Treatment Methods• Aerobic Digestion

– Biological treatment in presence of oxygen (time-temperature requirement)

• Anaerobic Digestion– Biological treatment in absence of oxygen (time-temperature

requirement)

• Lime Stabilization– Addition of lime to raise the pH above 12 for two hours

• Air Drying – Dried in open air for a minimum of three months

• Composing– Aerobic decomposition of organic material (time-temperature

requirement)

PFRP Treatment Methods• Composting

– Aerobic decomposition of organic material (time-temperature requirement)

• Heat Drying

– Heat used to reduce moisture content to <10%

• Heat Treatment

– Sewage sludge exposed to temperatures of >180°C for 30 minutes

• Thermophilic aerobic digestion

– Biological treatment in presence of oxygen and heat (time-temperature requirement)

• Beta ray or Gamma ray irradiation

– Pathogen destruction from radiation

• Pasteurization

– Sewage sludge is heated to temperatures of 70°C for 30 minutes

Vector Attraction Reduction Options

• Option 1: Reduce the mass of volatile solids by a minimum of 38 percent

• Option 2: Demonstrate vector attraction reduction with additional anaerobic digestion in a bench-scale unit

• Option 3: Demonstrate vector attraction reduction with additional aerobic digestion in a bench-scale unit

• Option 4: Meet a specific oxygen uptake rate (SOUR) for aerobically treated biosolids

• Option 5: Use aerobic processes at greater than 40°C (average temperature 45°C) for 14 days or longer (e.g., during biosolidscomposting)

Vector Attraction Reduction Options

• Option 6: Add alkaline materials to raise the pH under specified conditions

• Option 7: Reduce moisture content of biosolids that do not contain unstablized solids from other than primary treatment to at least 75 percent solids

• Option 8: Reduce moisture content of biosolids with unstabilizedsolids to at least 90 percent

• Option 9: Inject biosolids beneath the soil surface within a specified time, depending on the level of pathogen treatment

• Option 10: Incorporate biosolids applied to or placed on the land surface within specified time periods after application to or placement on the land surface

How Is Sewage Sludge Utilized?

Utilization Options

• Agricultural land application

• Reclamation (Marginal) land application

• Distribution

• Energy generation

• Disposal and alternative utilization at municipal landfills

• Incineration

• Innovative and research projects

Why Is Sewage Sludge Land Applied?

• Recycling a byproduct

• Returns essential nutrients to the soil

– Nitrogen, phosphorus, zinc and copper

• Adds organic matter to the soil

• Reduce fertilizer costs to farmers

• High water content

• Some sewage sludge contains a significant amount of lime that raises the pH of soil

Land Application of Sewage Sludge

• Regulated to…

– Protect the public health and the environment

– Ensure that the sewage sludge is treated to reduce and/or kill pathogens

– Ensure that the concentrations of metals are safe for land application

– Protect the quality of ground and surface water of the State

Information Required for a Agricultural Land Application Permit

• SSU Permit Application Form

• Owner's Consent Form signed by all legal

owners of the site

• Site Information Form

• Coastal Plain Soil pH Management Advisory

Form (if applicable)

• Sewage sludge sources

Information Required for a Agricultural Land Application Permit

• Topographic map

• Site specific map

• Sewage sludge analysis if not on file

– Percent solids and pH

– Nutrients

– Metals

– Others depending on treatment type

Information Required for a Agricultural Land Application Permit

• Soil survey map

• Tax map

• Detailed operational plan

• Documentation of haul route

• Performance bond or other financial security

Information Required for a Agricultural Land Application Permit

• A Nutrient Management Plan (NMP) prepared by a certified and licensed nutrient management consultant or certified operator in accordance with the COMAR 15.20.04 and in compliance with COMAR 15.20.07 and 15.20.08 (MDA Regulations)

– The NMP is a plan that is used to manage the amount, placement, timing and application of animal waste, fertilizer, sewage sludge or other plant nutrients in order to prevent pollution and maintain the productivity of soil when growing agricultural products.

Land Application Site Requirements

• Minimum Soil pH of 6.0

• Slope restrictions

• Adverse weather condition restrictions

• Trucks must be cleaned on site to prevent drag-out of soil or sewage sludge onto public roads

• Buffers areas are clearly marked with stakes or flags prior to sewage sludge application

Buffered Areas

Surface Application

of

Sewage Sludge with

no Incorporation

Injection of Sewage

Sludge or Surface

Application of Sewage

Sludge with

Incorporation

Bedrock 20 inches 20 inches

Bedrock outcrops 50 feet 25 feet

Field ditches 10 feet 10 feet

Incorporated municipality boundary lines 1,000 feet 400 feet

Occupied off-site dwelling 200 feet 100 feet

Occupied on-site dwelling 200 feet 100 feet

Property lines 50 feet 25 feet

Public roads 25 feet 15 feet

Surface waters unless Equivalent Best

Management Practices are installed100 feet 35 feet

Water table 20 inches 20 inches

Wells, Nonpotable 25 feet 25 feet

Wells, Potable 100 feet 100 feet

Buffer Requirements for Land Application

Land Application Site Requirements

• Following sewage sludge land application

– Signs may be posted at edges of fields

– Animal grazing is restricted for 30 days

– Public access to the site must be controlled for

one year

– No crops can be eaten raw by humans for

three years

General Permit Provisions

• Land application permits are issued for a period up to 5 years with renewal options

• Prior to sewage sludge land application the permittee informs

– MDE

– County Health Department, Environmental Health Division

General Permit Provisions

• Recordkeeping and reporting

– Source, type and quantity of sewage sludge received and applied on each field

– Cumulative and annual constituent loading rates

– Records kept on site during operations

– Records sent to MDE

• MDE’s control measures are designed to

protect the public health and the

environment.

• There have been no known cases of

disease transmission or contamination of

domestic drinking water supplies in

Maryland as a result of the application of

sewage sludge on agricultural land.

Informational Websites

• Maryland Department of the Environment

– www.mde.maryland.gov

• U.S. Environmental Protection Agency

– www.epa.gov

1800 Washington Boulevard | Baltimore, MD 21230-1718410-537-3000 | TTY Users: 1-800-735-2258

www.mde.state.md.us

Maryland Department of the Environment

Land Management AdministrationResource Management Program

Biosolids DivisionSewage Sludge Utilization Section

Phone (410) 537-3314Fax (410) 537-3321