WOOD PRESERVING RESOURCE

CONSERVATION AND RECOVERY ACT

COMPLIANCE GUIDE

A GUIDE TO FEDERAL ENVIRONMENTAL REGULATION

JUNE 1996

Office of Compliance

Office of Enforcement and Compliance Assurance

U.S. Environmental Protection Agency

401 M Street, SW (MC 2221-A)

Washington, DC 20460 

EPA-305-B-96-001
June 19, 1996

Introduction ii

******* IMPORTANT NOTICE *******

This document attempts to explain in one place the sometimes complex Federal requirements that

wood preserving facilities are subject to under the Resource Conservation and Recovery Act (RCRA).

This guidance document should not be interpreted as providing changes to existing regulations. It is

intended only as a clarification of existing regulations. Furthermore, because the Guide is designed to

summarize, in plain English, the applicable regulations and to provide additional information sources, it is

not a substitute for regulations published in the Code of Federal Regulations (CFR). In order to further

simplify the additional Federal regulations that apply to these facilities, background information on the

industry and summaries of other environmental statutes that effect this industry are included.

This document was prepared by EPA contractor Booz·Allen & Hamilton Inc. in close consultation

with an ad hoc task force composed of EPA and State inspectors. The document responds to questions

raised by industry personnel via the American Wood Preservers Institute. It has been reviewed by the

Association of State and Territorial Solid Waste Management Officials (ASTSWMO) and industry

representatives associated with the American Wood Preservers Institute.

This Guide is an outgrowth of the U.S. EPA’s Office of Compliance Sector Guide Project. During

the project, a series of 18 profiles on various industry sectors (as defined by two digit Standard Industrial

Codes) was developed containing information of general interest. The EPA document numbers of the

profiles range from EPA/310-R-95-001 to EPA/310-R-95-018. This Guide, which is in extension of the

Profile of the Lumber and Wood Products Industry (EPA/310-R-95-006), contains detailed information

on the Wood Preserving Industry (SIC 2491). The goals of the Guide are to provide environmental

professionals with useful information specific to the wood preserving industry, such as process descriptions

and the geographic distribution of the industry, and to address in plain-English many of the regulatory

interpretation questions that arose out of the RCRA drip pad standards and hazardous waste listings.

Cover photo courtesy of Universal Forest Products, Inc.
June 19, 1996

Introduction iii

The document can be purchased from the Superintendent of Documents, U.S. Government Printing Office.

All telephone orders should be directed to:

Superintendent of Documents

U.S. Government Printing Office

Washington, DC 20402

Phone (202) 512-1800

Fax (202) 512-2250

8:00 a.m. to 4:30 p.m., EST, M-F

All mail orders should be directed to:

U.S. Government Printing Office

P.O. Box 371954

Pittsburgh, PA 15250-7954

Complimentary volumes are available to certain groups or subscribers, such as public and academic

libraries, Federal, State, local, and foreign governments, and the media.

Electronic copies of this Guide are available at: www.epa.gov/oeca/metd/lumber.html

Comments or questions about this Guide should be addressed to:

U.S. Environmental Protection Agency

Wood Products Contact

Manufacturing Energy and Transportation Division (2223A)

401 M Street S.W.

Washington, D.C. 20460

Phone (202) 564-2300
June 19, 1996

Introduction iv

U.S. EPA would like to thank the many individuals from industry and government and especially the

participants on the EPA/State Wood Preserving Task Force and the American Wood Preservers Institute

RCRA Task Force for generously donating their time and expertise reviewing this Guide. EPA recognizes

that not all of those who reviewed the Guide agree with all of its content.

Wood Preserving Compliance Task Force Members

State Agency Representatives Phone

Yen Bao Virginia (804) 698-4403

Penny Brown West Virginia (304) 256-6850

Gary Calaba Oregon (503) 229-6534

Karen Cates Florida (904) 448-4320 ext. 368

Martin Herrick Wisconsin (608) 266-5798

Vonnie Kallemeyen South Dakota (605) 773-3153

Viki Leuba Washington (509) 625-5179

Jim McNamara Georgia (404) 657-8657

Andy Slusarski Maine (207) 287-2651

U.S. EPA Representatives Phone

Anthony Carrell Headquarters (703) 308-0458

Mike Fagan Region X (206) 553-6646

Bart George Region II (206) 637-3192

Bill Hamele Headquarters (202) 564-4012

Seth Heminway Headquarters (202) 564-7017

Bruce Long Region X-Oregon (503) 326-3686

Dan Patulski Region V (312) 886-0656

Bill Rothenmeyer Region VIII (303) 312-6045

Ron Shannon Region VI (214) 665-2282

Mike Silverman Region X-Idaho (208) 334-9389

Anna Torgrimson Region IV (207) 287-2651
June 19, 1996

Introduction v

Amercian Wood Preservers Institute Compliance Task Force

Gene Bartlow Scott Conklin

President Director of Wood Preservation

American Wood Preservers Institute Universal Forest Products

1945 Old Gallows Rd. Suite 150 2801 East Beltline N.E.

Vienna, VA 22182 Grand Rapids, MI 49505

(703) 893-4005 (616) 365-1563

Nick Bock Mr. Martin Rollins

Manager, Environmental Affairs and President

Regulatory Compliance H. Martin Rollins Company

Kerr-McGee Chemical Corp. P.O. Box 3471

P.O. Box 25861 Gulfport, MS 39505

Oklahoma City, OK 73125 (601) 832-1738

(405) 270-2394

Steve Smith Ross Worsham

Environmental Manager Senior Environmental Engineer

Koppers Industries, Inc. (rm. 1800) Atlantic Wood Industries Inc.

436 Seventh Ave. P.O. 1608

Pittsburgh, PA 15219-1800 Savannah, GA 31402

(412) 227- 2677 (912) 964-1234
Introduction vi

TABLE OF CONTENTS

SECTION 1 - INTRODUCTION

Introduction ................................................................. 1-1

Intended Audience ............................................................ 1-2

Scope of the Compliance Guide .................................................. 1-2

Potential for Increased State Stringency ............................................ 1-2

Using this Guide .............................................................. 1-3

References to Regulation ....................................................... 1-3

SECTION 2 - OVERVIEW OF THE WOOD PRESERVING INDUSTRY

Industry Overview ............................................................ 2-1

Surface Protection versus Wood Treatment ......................................... 2-1

Wood Preserving Process ...................................................... 2-3

Oil-Borne Processes .......................................................... 2-4

Health Concerns Associated with Wood Preserving Industry ............................. 2-8

Health Precautions for Plant Personnel ............................................ 2-10

SECTION 3 - GENERAL OVERVIEW OF RCRA

Introduction ................................................................. 3-1

Why the RCRA Program was Developed .......................................... 3-1

RCRA Program Goals ......................................................... 3-2

RCRA Subtitle C ............................................................. 3-2

Identification Of Hazardous Waste ................................................ 3-3

Hazardous Waste Under RCRA .................................................. 3-3

Characteristic Wastes .......................................................... 3-3

Listed Wastes ............................................................... 3-4

Hazardous Waste Mixtures ..................................................... 3-6

Contaminated Media .......................................................... 3-6

Derived-from Hazardous Waste .................................................. 3-7

Acutely Hazardous Waste ...................................................... 3-7

Generators Of Hazardous Waste ................................................. 3-7

Episodic Generation ........................................................... 3-9

Hazardous Waste Counting ..................................................... 3-9

General RCRA Requirements for Generators of Hazardous Waste ....................... 3-10

EPA Identification Number ..................................................... 3-10

Pre-Transport Requirements .................................................... 3-11

Accumulation Requirements .................................................... 3-11

Large Quantity Generators ..................................................... 3-11

Treatment in Generator Accumulation Units ........................................ 3-12

RCRA Air Emission Standards .................................................. 3-12
TABLE OF CONTENTS (CONT’D)

Introduction vii

Small Quantity Generators ..................................................... 3-12

Conditionally Exempt Small Quantity Generators ..................................... 3-13

Satellite Accumulation ........................................................ 3-13

Storage Requirements ........................................................ 3-14

Combined Use of Drip Pads, Containers, and Tanks/Sumps at Wood Preserving Facilities ..... 3-15

Manifest Requirements ........................................................ 3-16

Personnel Training ........................................................... 3-16

Contingency Plans ........................................................... 3-17

Recordkeeping and Reporting Requirements ........................................ 3-17

Land Disposal Restrictions ..................................................... 3-20

Waste Subject to LDR Requirements ............................................. 3-21

RCRA Permitting ............................................................ 3-22

Permit Exemptions ........................................................... 3-22

Permitting Standards ......................................................... 3-22

Permit Applications .......................................................... 3-23

Wood Preserving Facilities and Permits ........................................... 3-23

Closure Requirements at Permitted Facilities ........................................ 3-24

Post-Closure Requirements .................................................... 3-25

Closure of Wood Preserving Facilities ............................................ 3-25

Underground Storage Tanks .................................................... 3-26

State Authorization ........................................................... 3-26

SECTION 4 - RCRA WASTE GENERATED BY WOOD PRESERVING

Introduction ................................................................. 4-1

Health Concerns of Wood Preserving Wastes ........................................ 4-1

Wastewater ................................................................. 4-3

Process Residuals ............................................................ 4-3

Drippage and Process Residuals .................................................. 4-4

Contaminated Clothing and Other Materials ......................................... 4-5

Hazardous Wastes Generated by Wood Preserving Operations .......................... 4-5

Exclusions from the Definition of Solid Waste ........................................ 4-8

Closed Loop Recycling ........................................................ 4-9

Direct Use/Reuse ............................................................ 4-10

Reclaimed Spent Wood Preserving Solutions ....................................... 4-10

Wood Preserving State Authorization Issues ........................................ 4-13

Pollution Prevention Opportunities ............................................... 4-15

Pollution Prevention Case Study ................................................. 4-17

Frequently Asked Questions .................................................... 4-18

SECTION 5 - DRIP PADS
TABLE OF CONTENTS (CONT’D)

Introduction viii

Introduction ................................................................. 5-1

New vs. Existing Drip Pads ..................................................... 5-2

Drip Pad Design Standards ..................................................... 5-2

Sealed Drip Pads ............................................................. 5-5

Drip Pad Liners .............................................................. 5-5

Leak Detection Systems ........................................................ 5-6

Liquid Collection Systems ...................................................... 5-6

Run-on and Run-off Control .................................................... 5-7

Drip Pad Operation ........................................................... 5-7

Temporary Accumulation of Hazardous Waste on Drip Pads ............................ 5-7

Assessment of Drip Pad Integrity ................................................. 5-8

Existing Drip Pads ............................................................ 5-9

New Drip Pads ............................................................. 5-10

Inspections ................................................................. 5-11

The Operating Log ........................................................... 5-12

Releases of Hazardous Waste from Drip Pads ...................................... 5-13

Contingency Plans ........................................................... 5-14

Closure of Drip Pads ......................................................... 5-14

Frequently Asked Questions .................................................... 5-15

SECTION 6 - STORAGE YARDS

Introduction ................................................................. 6-1

Stormwater Run-off in Storage Yards .............................................. 6-2

SECTION 7 - TANKS AND SUMPS

Introduction ................................................................. 7-1

New vs. Existing Tanks ........................................................ 7-2

Assessment of Existing Tanks .................................................... 7-2

Assessment of New Tanks ...................................................... 7-2

Corrosion Protection .......................................................... 7-3

Leak Detection and Secondary Containment ......................................... 7-3

Leak Detection Systems ........................................................ 7-4

Secondary Containment Devices ................................................. 7-4

Exemption from Secondary Containment Requirement ................................. 7-5

Secondary Containment for Ancillary Equipment ...................................... 7-6

Operating and Maintenance Requirements .......................................... 7-6

Inspections .................................................................. 7-6

Response to Releases .......................................................... 7-7

Closure .................................................................... 7-7

Underground Storage Tanks ..................................................... 7-8
TABLE OF CONTENTS (CONT’D)

Introduction ix

SECTION 8 - ADDITIONAL STATUTORY REQUIREMENTS

Clean Water Act ............................................................. 8-1

NPDES Program ............................................................. 8-1

Stormwater Discharges ........................................................ 8-2

Pretreatment Program ......................................................... 8-3

Federal Insecticide, Fungicide, and Rodenticide Act ................................... 8-3

Clean Air Act ................................................................ 8-4

Comprehensive Environmental Response, Compensation and Liability Act ................... 8-6

Emergency Planning and Community Right-to-Know Act ............................... 8-7

Safe Drinking Water Act ...................................................... 8-19

Hazardous Materials Transportation Act ......................................... 8-110

Pollution Prevention Act ...................................................... 8-110

Toxic Substances Control Act .................................................. 8-11

APPENDICES

Appendix A Instructions on Electronic Access to this Guide

Appendix B Contact Lists

Appendix C Facility Checklist - RCRA Recordkeeping and Reporting Requirements for Wood

Preserving Facilities

Appendix D Subpart W (Drip Pad) Checklist

Appendix E Tank Systems Checklist for Generators (Subpart J)

Appendix F Facility Checklist - Other Laws
Introduction x

LIST OF EXHIBITS

Exhibit 1 Geographic Distribution of Wood Preserving Facilities ........................ 2-2

Exhibit 2 Industry Facility Size Distribution - 1992 ................................... 2-2

Exhibit 3 Wood Preserving Facility Process Schematic (oil-borne preservative) ............. 2-6

Exhibit 4 Wood Preserving Facility Process Schematic (water-borne preservative) .......... 2-7

Exhibit 5 Hazardous Waste Identification ......................................... 3-6

Exhibit 6 Code of Hazardous Waste Counting ..................................... 3-10

Exhibit 7 Requirements for Wood Preserving Facilities that are 

Generators of RCRA Hazardous Waste ............................... 3-19,20

Exhibit 8 Relationship Between State Authorization Status and 

HSWA/Non-HSWA Rulemakings ...................................... 3-28

Exhibit 9 Wood Preserving Process Inputs and Pollution Outputs ....................... 4-2

Exhibit 10 Hazardous Waste Generated at Wood Preserving Facilities ..................... 4-7

Exhibit 11 Wood Preserving Hazardous Waste Code Identification Table .................. 4-8

Exhibit 12 Codes of Hazardous Waste Identification for the Wood Preserving Industry ....... 4-12

Exhibit 13 State Authorization/Delegation of RCRA Wood Preserving Rules ............... 4-14

Exhibit 14 Side View of Typical Drip Pad .......................................... 5-4

Exhibit 15 Front View of Typical Drip Pad ......................................... 5-4

Exhibit 16 Drip Pad Construction and Certification Requirements ....................... 5-11

Exhibit 17 Responding to Drip Pad Cracks ........................................ 5-12
Introduction xi

LIST OF ACRONYMS

ACA Ammonical Copper Arsenate

ACC Acid Copper Chromate

ACQ Ammonical Copper Quat

ACZA Ammonical Copper Zinc

Arsenate

ARARs Applicable or Appropriate

Requirements

ASTSWMO Association of State and

Territorial Solid Waste

Management Officials

AWPI American Wood Preservers

Institute

CAA Clean Air Act

CAP Consumer Awareness

Program

CBA Copper Azole

CC Ammonical Copper Citrate

CCA Chromated Copper Arsenate

CDDC Copper

Dimethyldithiocarbomate

CERCLA Comprehensive

Environmental Response,

Compensation, and Liability

Act (commonly known as

Superfund)

CFR Code of Federal Regulations

CIS Consumer Information Sheet

CWA Clean Water Act

DOT U.S. Department of

Transportation

EHS Extremely Hazardous

Substance

EPA U.S. Environmental

Protection Agency

EPCRA Emergency Planning and

Community Right-to-Know

Act

FIFRA Federal Insecticide,

Fungicide, and Rodenticide

Act

FR Federal Register

HAPs Hazardous Air Pollutants

HSWA Hazardous and Solid Waste

Amendments (to RCRA)

LDR Land Disposal Restrictions

LEPC Local Emergency Planning

Committee

LQG Large Quantity Generator

MSDS Material Safety Data Sheet

NESHAPs National Emission Standards

for Hazardous Air Pollutants

NFPA National Fire Protection

Association

NIOSH National Institute for

Occupational Safety and

Health

NOI Notice of Intent

NPDES National Pollutant Discharge

Elimination System

NPL National Priorities List

NRC National Response Center

NSPS New Source Performance

Standards

OSHA Occupational Safety and

Health Act/Administration

PE Professional Engineer

PEL Permissible Exposure Limit

POTW Publicly-Owned Treatment

Works

PPE Personal Protective

Equipment
Introduction xii

RCRA Resource Conservation and

Recovery Act

RQ Reportable Quantity

SARA Superfund Amendments and

Reauthorization Act

SDWA Safe Drinking Water Act

SERC State Emergency Response

Commission

SIP State Implementation Plan

SQG Small Quantity Generator

TCLP Toxicity Characteristic

Leaching Procedure

TPQ Threshold Planning Quantity

TSCA Toxic Substances Control

Act

TSDF Treatment, Storage, and

Disposal Facility

TRI Toxic Release Inventory

UIC Underground Injection

Control

UST Underground Storage Tank

WAP Waste Analysis Plan
Introduction Section 1 - 1

SECTION 1

INTRODUCTION

Introduction The United States Environmental Protection Agency (EPA) has developed

this Wood Preserving RCRA Compliance Guide to provide summary

information on the statutory and regulatory requirements applicable to

wood preserving facilities. The document was developed for facilities that

use, or have used, wood preserving chemicals and have the potential to

generate waste that is considered hazardous under the Resource

Conservation and Recovery Act (RCRA). After numerous inspections of

wood preserving facilities, EPA has found that although many plants do

effectively control their wastes and comply with environmental regulations,

some do not. The purpose of the Guide is to help bring non-compliant

facilities into compliance by providing guidance and references to

applicable Federal environmental regulations. In addition, it will serve as

a reference tool for those facilities already in compliance so that

owners/operators may fine tune their understanding of these regulations.

This Guide was developed by a task force consisting of EPA and State

inspectors, and was a collaborative effort between these groups. In

addition, representatives of the wood preserving industry were consulted

about the questions that frequently arise within the industry and the

information that would be most useful for Guide readers. The Guide has

been reviewed by EPA and State inspectors as well as representatives of

the American Wood Preservers Institute (AWPI). EPA would like to

thank all of those who participated in the review process.

Although the Guide focuses on requirements imposed under RCRA's

hazardous waste management regulations, it also provides brief summaries

of other environmental statutes that may affect the wood preserving

industry. Explanations of regulatory requirements should help to build a

common base upon which both EPA inspectors and members of the

regulated community can form consistent interpretations of the Federal

regulations.

The discussions of the statutes and regulations in this document are not

intended to be exhaustive, but have been designed to be used for quick

reference. They are not meant to replace in-depth analysis of statutes,

regulations, or EPA guidance, and should not be considered a

replacement for knowledge of the regulations contained in the Code of

Federal Regulations (CFR). This document does not change or supersede

existing regulations, but rather seeks to clarify them.
June 19, 1996

Introduction Section 1 - 2

Intended Audience This document has been prepared for wood preserving facilities in the

United States. It is intended to provide an easy to understand summary

of the Federal environmental compliance requirements under RCRA that

regulate wood preserving facilities. EPA hopes that this Guide will assist

facility personnel by providing the information they need to achieve and

maintain compliance with applicable environmental regulations. EPA also

anticipates that the information presented here will be useful to Federal,

State, and local inspectors who may not be familiar with wood preserving

processes and the various management practices employed by the

industry. 

Scope of the 

Compliance Guide

The Guide provides a general overview of the wood preserving industry

in the United States and the Federal environmental regulations with which

the industry must comply. It is written primarily for those

owners/operators of facilities that are generators of RCRA hazardous

waste, not facilities that have RCRA permits, are operating under interim

status (see permitting discussion in Section 3), or that do not generate

hazardous waste at all (some wood preserving facilities use chemicals in

their processes that do not generate hazardous waste). The following

information is contained in this Guide:

• Size and geographic distribution of wood preserving facilities in

the United States

• General overview of RCRA requirements

• Types of wastes generated at wood preserving facilities

• Environmental compliance concerns relating to drips pads, tanks

and sumps, and storage yards at wood preserving facilities

• Additional relevant environmental statutes and regulatory schemes

• Answers to commonly asked questions concerning regulatory

requirements

• Names and phone numbers of organizations that can provide

additional information.

Potential for 

Increased State 

Stringency

It is important to note that State and local restrictions concerning wood

preserving facilities may, in fact, be more stringent than Federal

regulations. Individual State requirements are not discussed in this Guide,

but may be applicable to facilities within that State. Thus, it is imperative

that owners/operators of wood preserving facilities seek additional

guidance in determining the applicability of more stringent State and local

requirements. State authorization issues as they directly apply to the wood

preserving industry are discussed in more detail in Section 4 of this Guide.
June 19, 1996

Introduction Section 1 - 3

Using this Guide In addition to a detailed description of RCRA regulations that apply to the

wood preserving industry, this Guide also contains a general summary of

other aspects of the Federal RCRA program and its regulations. Readers

who have extensive experience with wood preserving facilities may

choose to skim over Section 2 (overview of wood preserving industry)

and Section 3 (overview of RCRA), and focus on Sections 4 through 7

(wood preserving wastes and regulations applicable to wood preserving

facilities).

References to 

Regulation

The end of each section contains a shaded box with regulatory citations

and references to information discussed in that section. Please consult

these regulations and other references for a more in-depth discussion of

applicable requirements.
Industry Overview Section 2 - 1

SECTION 2

OVERVIEW OF THE WOOD PRESERVING INDUSTRY

Industry

Overview

Note: This section has been included to give State and EPA

inspectors at wood preserving facilities a brief overview of the

industry. Much of the information presented in this section is

common knowledge to members of the wood preserving industry.

Surface Protection 

versus Wood 

Treatment

The purpose of wood preserving, also called wood treatment, is to

provide long-term protection from the damaging effects of fungi, insects,

and marine borers, thereby extending the usable life of wood products.

This is accomplished through the application of an EPA registered

preservative solution to timber. Wood treatment is different from surface

protection processes in that surface protection is characterized by nonpressure applications to the surface of the wood that are designed to

provide short-term cosmetic protection against mold and sap stains.

Wood preserving, on the other hand, involves the penetration of

preservative solutions into wood to preserve its structural integrity and

improve its resistance to weathering, water, and ground contact. Wood

surface protection and wood preserving are often confused since,

historically, chlorophenolic formulations were used in both processes.

Chlorophenolic formulations are now only used in wood preserving. In

addition, while EPA has chosen to specifically identify wastes from the

wood preserving industry that use chlorophenolic formulations as

hazardous wastes, the Agency also concluded that the regulation of

chemicals that are now used in surface protection is not warranted on the

Federal level.

Almost all timber is processed in some way before being sold. The

following wood products are normally treated in a preservation process

before commercial distribution: dimensional lumber (i.e., lumber that has

been cut to a specific shape or size) that will endure prolonged exposure

to the ground or weather, railroad ties, telephone poles, telephone cross

arms, bridge beams, fencing, window sills, doors, and pilings.

Geographic

Distribution of 

Wood Preserving

Wood preserving facilities are located in varying numbers in almost every

State. As indicated in Exhibit 1, the highest concentration of facilities is in

the Southeast and Northwest where there is a ready supply of raw wood.

Exhibit 2 illustrates the size of wood preserving operations in the industry.
June 19, 1996

Industry Overview Section 2 - 2

15

14

12

1

2

2

1

6

6

1

5

2

4

28

10

3

0

9

3

24

18

20

10

11

13

13 10

9

12

24 46 48

16

29

18

31

21

0

6

Total: 551 Puerto Rico 6

20

6

1

1

4

1

1

2

6

0

0

Exhibit 1

Geographic Distribution of Wood Preserving Facilities

Source: These figures were compiled through consultation with field personnel in each State or EPA Region. Because

exhaustive confirmation was not done on the number of facilities in all States, these numbers should be

considered estimates.

Exhibit 2

Industry Facility Size Distribution - 1992

Type of Facility

Facilities with 

1 to 19 employees

Facilities with 

20 to 99 employees

Facilities with 

100 or more employees Total

SIC 2491 - 

Wood Preserving 307 168 11 486

Source: Based on 1992 Bureau of the Census Data.

According to 1992 census data, of the total of 486 wood preserving

facilities, a large portion of them, approximately 63 percent, employed

between 1 and 19 people, 34 percent employed between 20 and 99

people, and 2 percent of the facilities employed over 100 people. The

bulk of wood preserving facilities are small operations, that are usually

supplied with preservative formulation by several larger national chemical
June 19, 1996

Industry Overview Section 2 - 3

companies. The chemical supply companies frequently offer their clients

training and guidance on complying with environmental regulations as well

as professional services such as hazardous waste management and

engineering. There also appears to be a trend in the industry toward larger

companies acquiring independent wood preserving companies and

operating them as subsidiaries.

Note: EPA has not attempted to reconcile the Bureau of the Census

data with its own facility count. This data is mentioned because it

gives a valuable indication of the relative size of wood preserving

facilities.

Wood Preserving 

Process

The preservation process that is applied to a particular bundle, or charge,

of wood varies with the type of wood being treated and any particular

product specifications that the wood treater may need to consider (e.g.,

wood that is used for construction of outdoor structures warrants a higher

degree of protection due to prolonged exposure to climatic elements).

Wood is porous and each wood preserving process takes advantage of

this fact to impregnate the wood with preservative. In most cases, the

process begins with a preliminary conditioning step that assures a

prescribed moisture content in the wood. Less moisture allows more

preservative to penetrate and remain in the wood, providing increased

protection. 

To change the moisture content, a variety of steps can be taken. These

include: air or kiln drying; Boulton drying, which consists of pulling a

vacuum on the treating cylinder while the wood is immersed in a heated

oil-borne solution; or steam conditioning, which consists of heating the

wood in the treating cylinder with steam for several hours then rapidly

vacuuming the wood to remove moisture. The pressure or treatment

cylinder where the preservative is actually applied to the wood is

commonly called a retort.

After conditioning, preservative solution is applied to the wood. Most

facilities use pressurized cylinders (retorts) to apply the preservative

solution. This involves placing charges of wood into the retort and

applying the preservative under a pressure system until sufficient

penetration and retention of the preservative into the wood has occurred.

The desired degree of penetration and retention is determined by

prescribed product specifications and will dictate how long the pressure

is applied. Excess preservative is drawn from the wood through a vacuum

system, and pumped back into the process tank, where it will be used

again in the same process. 
June 19, 1996

Industry Overview Section 2 - 4

A small percentage of facilities use non-pressurized dip tanks to treat

wood. This involves simply lowering the charges into a vat of

preservative, usually an oil-borne preservative. The charge is then

allowed to soak in the vat until a predetermined degree of penetration is

reached. Penetration is sometimes aided by heating and then cooling the

preservative.

There are a number of common pressure processes currently used by the

wood preserving industry to treat wood. These include full-cell, modified

full-cell, and empty-cell processes. Also, a variety of preservatives are

used, which are either water- or oil-borne. The different wood preserving

processes and solutions are discussed below.

Oil-Borne Processes Two primary types of pressure vacuum treatments, empty-cell and fullcell, are used to apply oil-borne preservatives. Examples of oil-borne

preservatives include creosote, creosote petroleum mixtures, copper

napthenate, and pentachlorophenol. Creosote is commonly used to treat

railroad ties, telephone poles, pilings, and bridge beams, while

pentachlorophenol is most often mixed into solution with oil to treat

telephone poles. 

The most widely used process is called empty-cell. In this process, the

cells of the wood are merely coated with preservative. The empty-cell

process obtains deep penetration of preservative and attempts to leave the

cell walls of the wood treated, while leaving a minimum of excess

preservative in the void spaces of the cells. Because a smaller amount of

preservative is used compared to the full-cell processes, the product is

lighter and easier to ship. The empty-cell process also results in less

expensive treatment costs for the facility since less preservative remains in

the wood.

One type of empty-cell process is the Lowry process, which entails filling

the retort with preservative while maintaining atmospheric pressure. When

the retort is filled with preservative, pressure is applied, forcing

preservative into the wood. This compresses the air contained in the cells

of the wood, allowing preservative to fill the balance of the cell. Once the

desired amount of preservative has been injected, usually over the course

of several hours, the retort is drained and a final vacuum is applied.

During this last step, much of the preservative in the cells is forced out by

the remaining air in the cells of the wood, which expands as it is subjected

to the vacuum and then returned to ambient pressure. This vacuum also

minimizes drippage after the charge is removed from the retort and is

placed onto the drip pad.
June 19, 1996

Industry Overview Section 2 - 5

The most widely used empty-cell process is the Rueping process in

which air pressure is applied and maintained in the retort prior to filling the

retort with preservative. When the retort is completely filled with

preservative, pressure is applied to force the solution into the wood.

Once the pressure is released, the retort is drained and the final vacuum

is applied. As a result of internal pressure, even more preservative is

forced out of the wood than in the Lowry process. 

The second type of wood preserving process is called the full-cell (or

Bethell) process because it results in a higher retention level by nearly

filling the wood cells with preservative. In this process, most of the air in

the retort is pumped out, creating a strong vacuum which is then held to

draw most of the air out of the wood. The retort is then filled with

preservative without breaking the vacuum, forcing preservative into the

cell spaces that have been created by the evacuated air. When the retort

is completely filled with preservative, pressure is applied to force the

solution into the wood. Once the pressure is released, the preservative is

pumped out of the retort and a final vacuum is drawn to force out excess

preservative. When the vacuum is released, much of the remaining surface

preservative is drawn back into the wood, reducing the amount of

drippage once the charge is taken out of the retort. Exhibit 3 on the next

page illustrates the oil-borne wood preserving process.

Full-cell and modified full-cell processes are used to apply water-borne

preservatives. The full-cell process utilized at water-borne facilities is very

similar to that used for oil-borne preservatives. The modified full-cell

process applies a weaker, or lower, initial vacuum to retain more air in the

cells of the wood. Once the pressure treatment phase is complete, the

remaining air (now expanding because pressure has stopped) displaces the

preservative which is, in turn, forced out of the wood. By forcing more

preservative out of the wood, weight is minimized and subsequent shipping

costs are reduced. Exhibit 4 illustrates the water-borne wood preserving

processes.
June 19, 1996

Industry Overview Section 2 - 6

Exhibit 3

Wood Preserving Facility Process Schematic

(oil-borne preservative)
June 19, 1996

Industry Overview Section 2 - 7

Exhibit 4

Wood Preserving Facility Process Schematic

(water-borne preservative)
June 19, 1996

Industry Overview Section 2 - 8

Water-borne preservatives contain active ingredients that are inorganic

metal oxides, or less frequently salts, and are commonly used to treat

dimensional lumber and telephone poles. This type of preservative

includes oxine copper, ammonical copper citrate (CC), copper azole

(CBA), copper dimethyldithiocarbomate (CDDC), chromated copper

arsenate (CCA), ammonical copper arsenate (ACA), acid copper

chromate (ACC), ammonical copper zinc arsenate (ACZA), and

ammonical copper quat (ACQ). As this Guide will discuss, wastes that

are generated by wood preserving facilities, especially those using

creosote, chlorophenolic, or arsenical-based preservatives, have the

potential to be considered hazardous waste under RCRA. Wastes

commonly generated in the wood preserving industry are discussed in

more detail in Section 6 of this Guide.

Past mismanagement of toxic chemicals at wood preserving facilities has

caused significant contamination of soil and groundwater at some sites. As

of May 1996, more than 45 wood preserving sites had been placed on

Superfund's National Priorities List (NPL) for priority cleanup of

contamination. The majority of contamination has been found at older

facilities that operated for many years before current environmental

regulations and disposal options existed. Along with other poor waste

management practices, contamination is generally caused by excess

preservative, called kickback, that has been allowed to drip onto the

ground from treated charges of wood.

A growing concern over the presence of dioxins and furans in

chlorophenolic wastes found at some facilities, coupled with the desire to

prevent the release of arsenic into the groundwater, has led EPA to

regulate the wood preserving industry under RCRA. In 1990, the first

RCRA regulations specifically addressing many wood preserving wastes

were published. These standards require owners/ operators of many

wood preserving operations to comply with RCRA. Subsequently, EPA

promulgated rules requiring tighter management of hazardous waste

generated by the wood preserving industry. As a result, many facilities in

the industry have invested heavily in cleaning up existing contamination and

complying with regulatory standards for facility construction and proper

waste management.

Health Concerns 

Associated with 

Wood Preserving 

Industry

The primary reason behind RCRA's preservative containment

requirements is to keep preservative chemicals out of ground and surface

waters. Contamination of soil and groundwater is a serious problem

because it can move considerable distances as it is picked up by water

moving through the soil and the water table. Because there are few, if any,
June 19, 1996

Industry Overview Section 2 - 9

naturally occurring organisms in the environment that can readily break

down these chemicals. Once the contamination enters the ground it has

the potential to linger for long periods of time and cause extensive

contamination to surrounding subsurface environments.The wood

preservatives creosote, pentachloro-phenol, and inorganic arsenicals

contain toxic constituents that have the potential to cause skin, eye, and

respiratory irritation as well as more serious ailments in humans, if humans

are overexposed to them. Some of these constituents have been classified

as carcinogens through epidemiological exposure studies on animals.

Exposure of aquatic plant and animal life to these toxic constituents has

also been found to have adverse effects.

Toxic constituents in wastes generated by the wood preserving industry

have been found to have chronic systemic effects on laboratory animals as

well as humans and have been determined to be present in sufficient

concentrations to pose a substantial threat to human health and the

environment. For example, previous studies of pentachlorophenol have

shown it to be highly toxic to humans. Exposure to pentachlorophenol can

cause contact dermatitis, damage to vision, and upon ingestion, lung, liver,

and kidney damage. Inhalation of pentachlorophenol can result in acute

poisoning, centering on the circulatory system with possible accompanying

heart failure. Other studies have shown pentachlorophenol to be a

carcinogen. 

One of the most commonly used preservatives in the wood preserving

industry is chromated copper arsenate, or CCA. This formulation

contains water, arsenic acid, chromic acid, and copper oxide.

Overexposure to CCA can damage mucous membranes and tissues of the

respiratory system and cause chemical burns on the skin and even skin

lesions. Ingestion of large amounts of CCA may have more serious

effects. Chronic exposure to significant doses of the chemical components

of CAA can lead to mental confusion, loss of coordination, and impaired

senses of touch, pain, and temperature. CCA is also considered a

possible carcinogen.

From this data, it is clear that many of the chemicals used in the wood

preserving industry have the potential to threaten human health when

handled in an unsafe manner. As a result, it is crucial that plant employees,

and anyone else coming into contact with preservative solutions containing

these constituents, be extremely cautious when handling the chemicals.

Some recommended precautions are discussed below.

Health Precautions 

for Plant Personnel

In order to minimize exposure to wood preserving chemicals, operators

of wood treatment equipment should closely follow company policy and
June 19, 1996

Industry Overview Section 2 - 10

Additional information is available on the subjects discussed above:

• For more information on the wood preserving process, consult The Preservation of Wood, A Self

Study Manual for Wood Treatment. Revised by F. Thomas Milton, University of Minnesota,

College of Natural Resources, Department of Forest Products, 1994.

• Preservative Treatment of Wood by Pressure Methods. ID, McLean, USDA Agriculture

handbook, No. 4D, December 1952 (Reprinted with corrections September 1960).

• Wood as an Engineering Material; Wood Handbook, Chapters 17-19. USDA Agriculture

Handbook, No. 72, Revised 1974.

• Wood Deterioration and its Prevention by Preservative Treatment. Darrel D. Nicholas, editor,

with the assistance of Wesley E. Loos, Syracuse University Press, 1973 (two volumes).

all applicable Federal, State, and local regulations concerning use and

management of those chemicals. At a minimum, facility personnel should:

• Use preservatives in accordance with the EPA approved

manufacturer’s label.

• Follow pesticide label and Occupational Safety and Health Act

(OSHA) requirements for personal protective equipment.

• Avoid direct contact with the chemicals by wearing protective

gloves and washing hands and other exposed skin before eating,

using tobacco products, or using the rest room.

• Enter the retort or other confined space only in accordance with

an OSHA confined space entry plan.

• Wear a respirator in process areas at inorganic arsenial wood

treating plants, unless PEL air monitoring has demonstrated that

it is safe not to wear one.
RCRA Overview Section 3 - 1

SECTION 3

GENERAL OVERVIEW OF RCRA

Introduction This section of the Compliance Guide contains a basic discussion of the

requirements imposed on wood preserving facilities by RCRA. This

section will cover the following general topics:

• Why the RCRA program was developed

• Identification of hazardous waste

• Generators of hazardous waste

• Hazardous waste management

• Land disposal restrictions

• RCRA permitting

• Closure of hazardous waste management units

• Underground storage tank requirements

• State authorization.

Note:Readers who are already familiar with the RCRA program may

not find it necessary to read this section of the Guide, but rather,

should move directly to Section 4.

Why the RCRA 

Program was 

Developed

RCRA, an amendment to the Solid Waste Disposal Act, was enacted in

1976 to ensure the safe disposal of the huge volumes of municipal and

industrial solid waste generated nationwide. RCRA has been amended by

Congress several times, most significantly in November 1984, by the

Hazardous and Solid Waste Amendments (HSWA). These amendments

significantly expanded the scope and requirements of RCRA, resulting in

the regulation of much of the waste generated in this country, both

hazardous and non-hazardous.

Many of the wood preserving facilities in the United States were in

operation long before the inception of the RCRA program. Although

RCRA creates a framework for the proper management of hazardous and

non-hazardous waste, it does not directly address the problems of

hazardous waste associated with inactive or abandoned sites, or spills of

chemicals that may require emergency response. Many wood preserving

sites, both inactive and operating, already contain significant soil and

groundwater contamination as a result of years of chemical use prior to the

enactment of environmental regulations. RCRA's Corrective Action

Program plays a role in requiring the cleanup of such historically

contaminated sites; however, this type of problem can also be addressed
June 19, 1996

RCRA Overview Section 3 - 2

under the Comprehensive Environmental Response, Compensation and

Liability Act (CERCLA). CERCLA, commonly known as Superfund,

mandates the cleanup of historically contaminated sites. In addition to

such remedial activities, Superfund also requires owners/operators of

facilities to notify EPA in the event of a release of certain hazardous

substances into the environment. See Section 8 for more information on

the Superfund program.

RCRA Program 

Goals The RCRA program is based upon three distinct goals aimed at creating

a safe and effective hazardous waste management system. They are:

• Protection of human health and the environment

• Reduction of waste and conservation of energy and natural

resource

• Reduction or elimination of the generation of hazardous waste.

RCRA is divided into ten sections, or subtitles, that provide EPA with a

framework to achieve these goals. For example, Subtitle D governs the

management of non-hazardous solid waste, while Subtitle I creates a

regulatory program for the management of underground storage tanks.

Subtitle C, which addresses hazardous waste management, is the subtitle

which has the greatest impact on the regulation of wood preserving

facilities. 

RCRA Subtitle C Subtitle C of RCRA establishes a "cradle-to-grave" management system

for controlling hazardous waste from its point of generation to final

disposal. The objective of Subtitle C is to ensure that hazardous waste is

handled in a manner protective of human health and the environment.

Pursuant to Subtitle C, EPA has issued regulations regarding the

generation, transportation, treatment, storage, and disposal of hazardous

waste. Facilities affected by these regulations must be maintained and

operated in a manner that will minimize danger to human health and the

environment. Many of the regulations that specifically address the wood

preserving industry concern the construction, operation, and maintenance

of hazardous waste drip pads. These drip pad requirements are found in

a specific subsection of Subtitle C called Subpart W. Those within the

wood preserving industry commonly refer to the drip pad regulations as

the "Subpart W standards" or "RCRA Subpart W."
June 19, 1996

RCRA Overview Section 3 - 3

Subtitle C is discussed in greater detail below. Both the general

requirements of Subtitle C, as well as those specific to the wood

preserving industry, are included.

Identification of 

Hazardous Waste

The regulatory framework established under Subtitle C of RCRA was

designed to protect human health and the environment from the effects of

improper management of hazardous waste. As a result, identifying

whether a waste is hazardous is crucial in determining the applicability of

the Subtitle C regulations.

Wastes are considered hazardous for different reasons, and the

responsibility for determining if a particular waste is hazardous falls on the

generator of that waste (see the discussion of hazardous waste generators

in Section 4).

In general, RCRA defines hazardous waste as a solid waste, which

because of its quantity, concentration, or physical or chemical

characteristics may:

• Cause or contribute to significant injury or death, or

• Damage or pollute the land, air, or water.

Hazardous Waste 

Under RCRA

A solid waste, defined by RCRA as any material including liquids, sludges,

and contained gases that is disposed, burned, or recycled in a certain

manner, is considered hazardous if it:

• Exhibits any one of the characteristics of a hazardous waste

• Has been specifically listed as a hazardous waste in the

regulations

• Is a mixture containing a listed hazardous waste and a nonhazardous waste

• Is a waste derived from the treatment, storage, or disposal of a

listed hazardous waste.

Each of these four categories is discussed in greater detail below. 

Characteristic 

Wastes

Characteristic wastes, as defined under RCRA, are identified by a specific

number, or waste code, that begins with the letter "D." A waste is

hazardous if it exhibits one or more of the following characteristics:
June 19, 1996

RCRA Overview Section 3 - 4

• Toxicity (D004-D043)—The toxicity characteristic identifies a

list of constituents that, if present in concentrations greater than

specified levels, are considered a threat to human health and the

environment. A test called the Toxicity Characteristic Leaching

Procedure (TCLP) demonstrates whether a waste contains levels

of hazardous constituents above regulatory thresholds. Wastes

exhibiting the toxicity characteristic are given specific waste codes

depending on the hazardous constituent of concern. For example,

TCLP results indicating levels of arsenic or chromium greater than

5.0 parts per million (ppm) in a waste stream are toxic for arsenic

and chromium, and are given the waste codes "D004" and

"D007," respectively. Wastes generated by the wood preserving

process are likely to exhibit the characteristic of toxicity.

• Ignitability (D001)—These wastes are easily combustible or

flammable. Examples of ignitable wastes include spent solvents

and discarded fuels.

• Corrosivity (D002)—These wastes dissolve metals or other

materials, or burn the skin. Common corrosive wastes include

caustic soda and nitric acids.

• Reactivity (D003)—These wastes are unstable or undergo rapid

or violent chemical reaction with water or other materials.

Cyanide- or sulfide-bearing wastes typically exhibit the

characteristic of reactivity.

Listed Wastes In addition to the four characteristic wastes, a waste is also hazardous if

it is specifically identified on one of four lists developed by EPA. A

hazardous waste listing is a narrative description of a specific type of

waste that EPA considers dangerous enough to warrant regulation.

Hazardous waste listings describe wastes from specific sectors of industry

(e.g., the wood preserving industry), or specific chemical formulations. 

Before developing a listing, EPA thoroughly studies a particular waste

stream and the threat it can pose to human health and the environment. If

the waste poses a great enough threat to warrant regulation, EPA includes

a precise description of that waste on one of the hazardous waste lists.

Any waste that meets the narrative listing description is considered

hazardous, regardless of its chemical composition or any other potential

variable. The three types of listed wastes are:
June 19, 1996

RCRA Overview Section 3 - 5

• F-listed wastes—Wastes from nonspecific sources that are

produced by a number of manufacturing and industrial processes.

Examples of F-listed wastes commonly generated by the wood

preserving industry are wastes generated from processes that use

chlorophenolic formulations (F032), creosote (F034), and

inorganic preservatives containing arsenic or chromium (F035).

• K-listed wastes—Specific source wastes generated by

particular industries identified by EPA. Wood preserving

operations are among those identified in the regulations. As such,

many wood preserving facilities that employ processes that use

creosote and/or pentachlorophenol have the potential to generate

K-listed waste, "K001."

Note: Many owners/operators overlook the possibility of a waste

meeting the K001 description. This listing is for bottom sediment

sludge from the treatment of wastewaters from wood preserving

processes that use creosote and/or pentachlorophenol. Also, it should

be noted that any waste stream meeting the K001 waste code

description cannot also be classified as one of the F-listed wood

preserving wastes (F032, F034, or F035). These F listings

specifically exclude K001 wastes.

• P-listed wastes—Specific unused or off-specification

commercial chemical products that are being discarded. EPA

has specifically identified wastes on the P-list as being acutely

hazardous.

• U-listed wastes—Specific unused or off-specification

commercial chemical products that are being discarded. An

example of a potential U-listed waste that may be of concern to

the wood preserving industry is unused creosote (U051).

Exhibit 5 outlines some of the questions that should be asked to determine

whether a waste is hazardous under RCRA Subtitle C.
June 19, 1996

RCRA Overview Section 3 - 6

Is the Waste

Specifically

Listed?

Does the Waste Exhibit a

Characteristic of Hazardous Waste

(i.e., Ignitability, Corrosivity,

Reactivity, or Toxicity)?

No

Yes

Not Subject to

RCRA Subtitle C

No

Yes

Hazardous Waste Subject to RCRA Subtitle C

Exhibit 5

Hazardous Waste Determination

Note: This chart assumes that a number of other decisions concerning hazardous waste determination have been

made. Specifically, the information in the chart assumes that the waste in question has already been determined

to be a solid waste under RCRA (§261.2), and that the waste is not otherwise excluded from RCRA regulation in

any way (e.g., under §§260.30, 261.2, or 261.4).

Hazardous Waste 

Mixtures

RCRA also regulates the waste resulting from the mixture of hazardous

and nonhazardous wastes. A mixture involving characteristic wastes is

hazardous only if the mixture itself exhibits a characteristic. Under the

"mixture rule" for listed wastes, however, a mixture made up of nonhazardous solid waste and any amount of a listed hazardous waste is,

itself, a listed hazardous waste. The mixture will bear the same waste

code and regulatory status as the original listed component of the mixture.

This principle applies regardless of the percentage of listed waste in the

waste mixture, the actual threat posed by the waste mixture, or the

mixture's chemical composition. The mixture rule was originally created

to prevent the dilution of listed wastes as a substitute for treatment

activities.

Contaminated Media EPA's contained-in policy addresses environmental media (e.g., soil,

sediment, and groundwater) contaminated with hazardous waste.

According to this policy, any media that is contaminated with a listed

waste must be managed as that listed hazardous waste. To determine

whether a media contains a hazardous waste, owners/operators must have

complete, accurate, and historical information pertaining to past and

present waste management operations at the facility. If constituents of

concern in the soil cannot be linked to a process that generated a listed

hazardous waste, then the contained-in policy will not apply. Unlike the

mixture rule (described above), however, any media that is contaminated

with a listed waste can lose its status and become non-hazardous. This
June 19, 1996

RCRA Overview Section 3 - 7

occurs when it is demonstrated that the contaminated media no longer

"contains" the listed hazardous waste. This is accomplished by bringing

the levels of contamination below a predetermined level established by the

appropriate implementing agency. Once this demonstration is made, the

media is no longer considered to "contain" a listed waste and is no longer

regulated under Subtitle C. 

Similarly, any contaminated media that exhibits a characteristic of

hazardous waste is also considered hazardous waste and subject to

regulation. A media that exhibits a characteristic of hazardous waste can

be rendered non-hazardous by removing the characteristic.

Derived-from 

Hazardous Waste

Any residue resulting from the treatment, storage, or disposal of a listed

waste is considered a hazardous waste. Examples of derived-from wastes

include: ash resulting from the combustion of hazardous waste, and sludges

generated from the treatment of hazardous wastewaters.

Acutely Hazardous 

Waste

Some hazardous wastes are considered to be "acutely hazardous." These

are wastes that EPA has determined to be so dangerous in small amounts

that they are regulated in the same manner as large amounts of other

hazardous wastes. Acutely hazardous wastes include certain dioxincontaining wastes and those unused commercial chemical products

identified as P-listed wastes. The listed wastes generated at wood

preserving plants that use or formerly used chlorophenolic preservative

formulations are likely to contain dioxins. EPA has determined that

pentachlorophenolic wastes are toxic, not acutely hazardous.

Generators Of 

Hazardous Waste

As stated previously, RCRA regulates hazardous waste from the point of

generation through final disposal. Hazardous waste generators are the first

link in this cradle-to-grave hazardous waste management system. EPA

has established comprehensive standards for generators managing

hazardous waste, including standards for on-site accumulation, waste

tracking, labeling, recordkeeping, and reporting requirements. 

Because generators produce waste in different quantities, EPA has

established three categories of waste generators:

• Large quantity generators (LQG) generate 1000 kilograms

(kg) (approximately 2200 pounds or 300 gallons) or more of

hazardous waste per calendar month or more than 1 kg (2.2

pounds) of acutely hazardous waste. Any generator that
June 19, 1996

RCRA Overview Section 3 - 8

produces greater than 1 kg of acutely hazardous waste in a

calendar month must comply with all of the large quantity

generator requirements. Of the three classifications of hazardous

waste generators, large quantity generators are subject to the

most comprehensive standards.

• Small quantity generators (SQG) generate between 100 and

1000 kg of hazardous waste (between approximately 220 and

2200 pounds, or 25 and 300 gallons) per calendar month. Small

quantity generators are subject to a limited portion of the

regulations that apply to large quantity generators. Small quantity

generators may not accumulate more than 6000 kg of hazardous

waste or 1 kg (2.2 pounds) of acutely hazardous waste in a month

on-site at any one time. Small quantity generators who exceed

this accumulation limit must comply with the regulations for large

quantity generators.

• Conditionally exempt small quantity generators (CESQG)

generate 100 kg or less of hazardous waste (approximately 220

pounds or 25 gallons) per calendar month. These generators are

conditionally exempt from many of the regulations governing

hazardous waste generators, provided they do not accumulate

more than 1000 kg on-site at any one time and that any hazardous

waste generated is sent to a State- or Federally-approved facility.

Note: Under RCRA, many hazardous process wastewaters that are

either reclaimed or sent for treatment or disposal must be counted

toward a generator’s monthly status. As a result, it is unlikely that

many wood preserving facilities will meet this 100kg/month threshold

and be considered conditionally exempt small quantity generators.

Only the smallest wood preserving facilities would normally qualify

for this category.

Some State regulations may be more stringent than Federal regulations.

For example, a particular State may set lower cut-off levels for generator

status, or may eliminate one of the categories completely. Some States do

not recognize the conditionally exempt generator category. Please consult

the appropriate State implementing agency when determining the

generator status of a particular facility. Owners/operators of facilities

that generate hazardous waste are responsible for making the

correct generator status determination.
June 19, 1996

RCRA Overview Section 3 - 9

Episodic Generation Facilities that generate hazardous waste may be regulated under different

rules at different times, depending on the amount of waste generated in any

given month. For example, a small quantity generator that generates over

1000 kg of waste in a particular month must comply with the more

extensive large quantity generator requirements for the amount of time that

the waste remains on site. This fluctuating hazardous waste generation

pattern is known as episodic generation.

Hazardous Waste 

Counting

In order to determine the extent to which a facility is subject to the RCRA

generator regulations, each generator must "count" the amount of

hazardous waste produced at the facility in a calendar month and

determine generator status (i.e., large quantity, small quantity, or

conditionally exempt). Counting involves adding up the weight of all

quantities of characteristic and listed hazardous wastes generated at a

particular facility. Wastes should only be counted once toward a

generator's monthly status calculation.

Exhibit 6 may assist in deciding when a hazardous waste is to be counted

when making a generator's quantity determination. EPA requires that only

those wastes that are subject to "substantive regulation" be counted.

Substantive regulation includes any regulation directly related to the

storage, transportation, treatment, or disposal of hazardous wastes.

Regulations which would not be considered substantive include

requirements to notify and obtain an EPA identification number or to file

a Biennial Report.

Another discussion on hazardous waste counting as it pertains to wastes

specifically generated in the wood preserving industry is found in Section

4 of this Guide.
June 19, 1996

RCRA Overview Section 3 - 10

Exhibit 6

Hazardous Waste Counting

COUNTED NOT COUNTED

• Wastes accumulated on-site for any period

of time prior to their subsequent

management.

• Wastes packaged and transported off site.

• Wastes placed directly into a regulated onsite treatment, storage, or disposal unit.

• Wastes meeting the definition of F032, F034,

or F035.

• Wastes removed from exempt units (e.g.,

wastewater treatment units).

• Wastes generated as sludges and removed

from product storage tanks. 

• Examples:

- Process residuals, sludges.

- Wastewater that accumulates on the

drip pad and in the collection system,

e.g., drip pad sump.

- When discarded: metal banding (unless

recycled), wood stickers, personal

protective equipment.

• Hazardous waste removed from on-site storage.*

• Hazardous waste produced by on-site treatment

(including reclamation) so long as the treated waste

has already been counted once.

• Spent materials that are generated, reclaimed, and

subsequently reused on site, so long as the spent

material has already been counted once.

• Wastes excluded from the definition of solid waste

under §261.2, i.e., wastewater discharged to a POTW

or NPDES point source discharge.

• Wastes excluded from regulation under §261.4(a)-(f)

(e.g., arsenical treated wood that is discarded off the

drip pad (261.4(b)(9).

• Recyclable materials under §261.6(a)(3).

• Wastes reclaimed on-site without prior storage or

accumulation.

• Wastes managed in exempt units (e.g., astewater

treatment units).

• Residues left in empty containers (empty as per

§261.7).

• Universal wastes managed uner Part 273.

* EPA’s counting Guidelines are designed to account for those wastes that are subject to “substantive regulation.” 

These wastes should only be counted once, and not double counted. Therefore, in this example, because

hazardous wastes removed from hazardous waste storage have already been counted once, they need not be

counted again (§261.5(d)).

General RCRA

Requirements for

Generators of

Hazardous Waste

Large and small quantity generators are subject to several specific

requirements under RCRA. Regulations require generators to:

• Obtain an EPA identification number

• Properly prepare hazardous waste for transportation

• Follow accumulation and storage requirements

• Manifest hazardous waste

• Satisfy recordkeeping and reporting requirements

• Provide personnel training

• Develop contingency plans.
June 19, 1996

RCRA Overview Section 3 - 11

The specifics of the above requirements will differ depending upon a

facility's generator status. Each of the requirements mentioned above is

discussed in more detail below.

EPA Identification

Number

Each EPA identification number consists of a series of letters and digits.

The digits represent the specific facility, and the letters indicate in which

State the facility is located. EPA identification numbers are obtained by

filing Form 8700-12, "Notification of Regulated Waste Activity," with the

appropriate EPA Regional or State RCRA office. 

Without an EPA identification number, a generator cannot treat, store,

dispose of, transport, or offer for transport any hazardous waste. A

generator is also forbidden from offering hazardous waste to a transporter

or treatment, storage, or disposal facility (TSDF) that does not have an

EPA identification number. On the Federal level, conditionally exempt

small quantity generators are not required to obtain EPA identification

numbers; however, State policy may require conditionally exempt

generators to obtain EPA identification numbers.

Pre-Transport

Requirements

EPA has adopted the pre-transport regulations used by the U.S.

Department of Transportation (DOT). DOT regulations require proper

packaging to prevent leakage of hazardous materials, and labeling,

marking, and placarding of these wastes to identify characteristics and

potential dangers. For more information on DOT prepackaging

requirements, consult the regulations in 49 CFR.

Accumulation 

Requirements

Although storage of hazardous waste generally requires a RCRA permit,

RCRA allows generators to "accumulate" hazardous waste on-site without

a permit as long as they comply with specific limits and standards set out

for each generator category. 

Large Quantity

Generators

Large quantity generators may accumulate waste on-site for up to 90 days

without a RCRA permit as long as: 

• The waste is properly stored

• The facility has an contingency plan in place

• Facility personnel are trained in proper waste handling procedures.

Large quantity generators may only accumulate hazardous waste in

containers, tanks, containment buildings, or on drip pads. Each container
June 19, 1996

RCRA Overview Section 3 - 12

and tank must be labeled with the words "hazardous waste," and

generators must mark the accumulation start date on each container.

Tanks need not have the start date marked on them because they are

continually reused. Large quantity generators must, however, be able to

demonstrate through manifests and other records that the tank has been

emptied within the specified 90-day time frame.

Treatment in 

Generator

Accumulation Units

If a generator continues to store hazardous waste for longer than 90 days,

the facility will be considered a hazardous waste storage facility and must

obtain a RCRA permit (see discussion of RCRA permits below).

Although some States prohibit such action, under Federal regulations,

generators may perform treatment (except for thermal treatment such as

combustion and incineration) of hazardous waste in accumulation units

under the condition that they continue to comply with the general

management standards discussed above and do not exceed the 90-day

accumulation time limit.

RCRA Air Emission 

Standards

On December 6, 1994, EPA finalized its air emission standards under

RCRA to reduce volatile organic air emissions from waste management

operations. These standards, known as Subpart CC, affect

owners/operators managing hazardous waste with a certain volatile

organic concentration in tanks, surface impoundments, and containers.

Large quantity generators must comply with these regulations in order to

maintain their permit-exempt status. The Subpart CC standards are in the

final stages of development and are expected to become effective October

6, 1996. The Subpart CC standards do not apply to process tanks or to

wastewater treatment units at wood preserving facilities. Oil-borne

facilities using large tanks to store hazardous waste need to carefully

consider the applicability of Subpart CC.

Small Quantity

Generators

Small quantity generators may accumulate waste on-site for up to 180

days as long as:

• The on-site quantity does not exceed 6000 kg at any time

• At least one employee who is responsible for coordinating

emergency responses is either at the facility or on-call at all times

• The facility has basic safety information, including the name and

telephone number of the designated emergency coordinator,

location of fire extinguishers, spill control materials, and the fire

department phone number posted next to the telephone
June 19, 1996

RCRA Overview Section 3 - 13

• Personnel are familiar with the emergency procedures to be

followed in the event of a spill or accident. 

Note: As an exception to the 180-day accumulation time period,

small quantity generators may only store hazardous waste on drip

pads for 90 days, but may continue to store hazardous waste in

drums and tanks for up to 180 days (accumulation time is extended

to 270 days if the generator must transport the hazardous waste over

200 miles for off-site treatment, storage, or disposal).

If waste is stored in drums for longer than 180 days, the facility will be

considered a storage facility and must obtain a RCRA permit (see

discussion of RCRA permits below). Small quantity generators may also

treat hazardous waste in accumulation units provided they comply with the

general management and time limit restrictions discussed above.

Conditionally Exempt

Small Quantity

Generators

Conditionally exempt small quantity generators may accumulate

hazardous waste on-site as long as they do not have on-site, at any one

time, more than 1000 kg of hazardous waste, or 1 kg of acutely hazardous

waste. At the Federal level, there are no accumulation time limits for

conditionally exempt small quantity generators, and no recordkeeping,

personnel training, or emergency planning is required. However,

regulations require conditionally exempt generators to send their wastes

to one of five types of facilities (either a State- or Federally-approved

municipal or hazardous waste landfill, or a recycling facility). Conditionally

exempt generators are strongly encouraged to check with their State

hazardous waste agency to determine if the State has adopted more

stringent standards for generators of less than 100 kg.

Satellite 

Accumulation

Many generators temporarily store their hazardous waste in locations at

or near the point of generation before taking the waste to a central

accumulation area at the facility (i.e., the "90-day area"). This satellite

accumulation is permissible under Federal RCRA regulation, provided

certain criteria are met. Generators may accumulate up to 55 gallons of

hazardous waste, or one quart of acutely hazardous waste, at or near the

point of generation in satellite accumulation areas without triggering the

generator's "90-day clock." For example, wastes that are temporarily

accumulated right outside of the retort could qualify for the satellite

accumulation provision. The following requirements apply to satellite

accumulation:
June 19, 1996

RCRA Overview Section 3 - 14

• Containers must be labeled as "HAZARDOUS WASTE" or with

other words that identify the contents of the container.

• Once the 55-gallon limit is reached in the satellite accumulation

area, the containers must be removed within 72 hours and taken to

a central accumulation area.

• The 90- or 180-day facility accumulation limit begins with respect

to satellite accumulation waste as soon as the waste is removed

from the satellite accumulation area.

• When the 55-gallon limit is reached, generators must mark the

container with the start date that excess waste started to

accumulate. Generators then have three days to remove the

hazardous waste to a central accumulation area where the 90- or

180- day accumulation time will begin, depending on their generator

status.

EPA does not limit the number of satellite accumulation areas allowed at

a particular facility, nor does it specify the type or size of containers that

may be used. As long as the 55-gallon limit is not exceeded,

owners/operators may use a variety of containers to accumulate wastes

in a satellite area. Proper satellite areas should be designated in

conjunction with the appropriate State hazardous waste agency.

Storage

Requirements

Hazardous waste may be stored in 55-gallon drums, tanks, or other units

suitable for the type of waste generated.

If hazardous waste is stored in containers:

• The container must be clearly marked with the words

"HAZARDOUS WASTE" and with the date the accumulation

starts.

• Containers must be kept in good condition and replaced if they

begin to leak.

• Containers must be kept closed and sealed except when being

emptied or filled.

• Containers must be inspected each week for leaks or corrosion.

• If a container is used to store ignitable or reactive waste, it must be

placed at least 50 feet (15 meters) from the facility property line to

create a buffer zone. 

• Wastes that can react together must never be stored together to

prevent dangerous reactions upon contact.

Generators may also store hazardous waste in tanks, provided they meet

certain standards. All large quantity generators accumulating hazardous
June 19, 1996

RCRA Overview Section 3 - 15

waste in tanks must comply with the standards discussed in Section 7;

however, small quantity generators accumulating hazardous waste in tanks

are subject to special standards. 

If small quantity generators are accumulating hazardous waste in tanks:

• The tank must be kept covered or, if uncovered, there must be at

least two feet of space between the top of the tank and the waste

being stored (unless the tank is equipped with secondary

containment).

• If the tanks have equipment that allows waste to flow into them

continuously, waste feed cut-off or bypass systems must be

provided to stop the flow in case of problems.

• Monitoring or gauging systems must be inspected each operating

day and the tanks themselves must be inspected each week for

leaks or corrosion.

• For tanks containing ignitable or reactive wastes, a buffer zone must

be established between the tank and the facility property line. At

a minimum, buffer zones must meet appropriate National Fire

Protection Association (NFPA) requirements. Owners/operators

can obtain this information from the local fire department.

Combined Use of

Drip Pads,

Containers, and

Tanks/Sumps at

Wood Preserving

Facilities

It is possible for a wood preserving facility to use drip pads, containers,

and tanks to manage hazardous waste in the same operation. For

example, waste may be generated and accumulated on a drip pad for a

short period of time, then drained to a collection tank or sump. In

addition, many owners/operators also keep a drum located at the edge of

the drip pad to capture debris and residues that do not drain into the

collection unit and are picked up off the drip pad.

In combined use situations, it is important to know the regulatory status of

all waste accumulation units. The drip pad is specifically identified as an

accumulation unit in the RCRA regulations. The RCRA drip pad

standards require that all tanks and sumps used as drip pad collection units

meet the RCRA tank standards in Subpart J. As a result, these

tanks/sumps will also be subject to Subtitle C controls. Although it is

possible for these tanks to be fully regulated, collection tanks can be a part

of a facility's wastewater treatment system and thus exempt from RCRA

regulation. RCRA provides an exemption from regulations for wastewater

treatment units. If this is the case, the tank or sump would not be

regulated under Subpart J, but would be subject to regulation under the

Clean Water Act. 
June 19, 1996

RCRA Overview Section 3 - 16

To take advantage of the wastewater treatment unit exemption, the tank

has to be part of a system that is either discharging to a publicly-owned

treatment work (POTW) or subject to a National Pollutant Discharge

Elimination System (NPDES) zero discharge permit. It is the

responsibility of the facility's owner/operator to make these kinds of

determinations in conjunction with the appropriate State authority.

Containers that are kept on the edges of drip pads to collect materials

such as debris may be considered satellite accumulation areas under

RCRA. RCRA allows owners/operators to accumulate up to 55 gallons

of hazardous waste in areas at or near the point of generation before it is

transferred to a central accumulation unit.

Manifest 

Requirements

A generator who transports, or offers for transportation, hazardous waste

for off-site treatment, storage, or disposal must prepare a Uniform

Hazardous Waste Manifest (Form 8700-22A). Manifests allow

generators, as well as regulators, to track the movement of hazardous

waste from its point of generation to the point of ultimate treatment,

storage, or disposal. Each party that handles the waste must sign the

manifest and retain a copy. Once the transport is complete, the receiving

facility must return a signed copy of the manifest to the generator (within

60 days for small quantity generators, and within 45 days for large quantity

generators). If no copy of the signed manifest is received by the

generator, an exception report must be filed.

RCRA manifests contain the following information:

• Name and EPA identification number of the generator, transporter,

and the designated TSDF

• DOT description of the waste

• Quantity of waste

• Address of the designated TSDF to which the waste is being

transported

• Certification that the generator has in place a program to reduce the

volume or toxicity of waste and that the treatment, storage, and

disposal method chosen by the generator is the most practical

method currently available.

Personnel Training Large and small quantity generators must satisfy certain personnel training

requirements. These requirements help to ensure that all employees in

contact with hazardous waste are knowledgeable of the dangers involved

and educated on proper waste handling procedures and precautions.
June 19, 1996

RCRA Overview Section 3 - 17

Large quantity generators are subject to the same personnel training

requirements as permitted RCRA facilities. To fulfill these requirements,

facility personnel must successfully complete a program of classroom

instruction or on-the-job training that teaches them to perform their duties

in a safe and effective manner. Employees must complete the program

within six months after beginning their employment and must take part in

an annual review of the initial training. Small quantity generators are not

required to satisfy these requirements, but are responsible for ensuring that

facility personnel are instructed in proper waste handling procedures.

Conditionally exempt small quantity generators are not subject to

personnel training requirements.

Contingency Plans Generators are required to have a contingency plan in place at the facility

that outlines the proper response procedures necessary to minimize

hazards posed by fires, explosions, or unplanned releases of hazardous

waste from the facility. Similar to personnel training requirements, large

quantity generators are subject to the same contingency plan requirements

as permitted facilities. Details of the precautionary measures that must be

taken are found in the regulations. Extensive plans are not required for

small quantity generators; rather, small quantity generators must construct

a modified version of the plan. Conditionally exempt small quantity

generators are not required to have contingency plans. 

Recordkeeping and

Reporting

Requirements

Hazardous waste generators must satisfy several recordkeeping and

reporting requirements. Large quantity generators who transport

hazardous waste off-site must submit a biennial report to the EPA

Regional Administrator (or State director if the State is authorized to

implement the hazardous waste program) by March 1 of each evennumbered year. This report details the generator's activities during the

previous calendar year, including the quantity and nature of the hazardous

waste generated; and the name, address, and EPA identification number

of each TSDF to which waste was sent and each transporter who handled

the waste for the facility. The report must also describe the facility's

efforts to reduce the volume and toxicity of the wastes generated and the

changes in volume and toxicity actually achieved compared to previous

years (waste minimization report). Neither small quantity generators

nor conditionally exempt small quantity generators are required to submit

a biennial report.

To ensure the safe and efficient transport of hazardous waste to off-site

facilities, RCRA requires facilities to return a signed copy of the manifest
June 19, 1996

RCRA Overview Section 3 - 18

to the generator within a certain time frame. Small quantity generators

must receive a copy within 60 days, large quantity generators within 45

days. Owners/operators who do not receive a copy of the manifest

signed and dated by the TSDF within the appropriate time period must

submit an exception report. Although there is no specific form, the

contents of the exception report are specified in the regulations.

Conditionally exempt small quantity generators are not required to prepare

a manifest, and thus are not subject to the exception reporting

requirements.

Generators must keep signed copies of manifests for at least three years

from the date waste was accepted by the initial transporter. The generator

must also retain a copy of each biennial report for three years from the due

date of the report. In addition, a generator must keep records of any test

results or waste analyses for at least three years. The three-year period

for retention of records is automatically extended during an enforcement

action.

Exhibit 7 summarizes the different regulatory requirements for large

quantity, small quantity, and conditionally exempt generators. 
June 19, 1996

RCRA Overview Section 3 - 19

Exhibit 7

Requirements for Wood Preserving Facilities that are Generators of RCRA Hazardous Waste

Large Quantity Small Quantity Conditionally Exempt

Hazardous Waste

Quantity Limits

(per calendar

month)

31000 Kg hazardous waste

or

3 1 Kg acute hazardous

waste

Between 100-1000 Kg

hazardous waste

< 100 Kg

or

< 1 Kg acute hazardous 

waste

Waste

Determination

Yes Yes Yes

EPA ID Number Yes Yes No

On-Site

Accumulation

Quantity Limits

None 2 6000 Kg 2 1000 Kg

2 1 Kg acute hazardous

< 100 Kg spill residue from 

acute HW

Accumulation Time 2 90 days 2 180 days*

(2 270 days if travel to

waste management facility

is > 200 miles)

None

Storage

Requirements

Comply with all Part 265

management standards

for tanks, containers, drip

pads, and containment

buildings

Comply with basic

technical requirements for

tanks and containers*

None

Off-Site Waste

Management

RCRA permitted or interim

status HW facility

RCRA permitted or interim

status HW facility

State approved or RCRA

permitted/interim status

facility or recycling facility

Contingency Plan Full plan to minimize

hazards from fires, spills,

explosion

One person at the facility

at all times responsible for

coordinating emergency

responses

None

Storage Yard

Cleanup Plan

Yes Yes No

Subpart W Drip

Pad Standards

Yes Yes No**

Treatment on Site

without a RCRA

Permit

Yes (except for thermal

treatment such as

combustion and

incineration)

Yes (except for thermal

treatment such as

combustion and

incineration)

No, unless the CESQG is

also one of the types of

waste management

facilities specified above

Manifest Yes Yes No

Biennial Report Yes No No
June 19, 1996

Exhibit 7

Requirements for Wood Preserving Facilities that are Generators of RCRA Hazardous Waste

Large Quantity Small Quantity Conditionally Exempt

RCRA Overview Section 3 - 20

Recordkeeping • Manifests

• Biennial reports

• Exception reports

• Test results 

• Records of past

management practices

• Records of storage

yard cleanup

• Documentation if any

past decontamination

of equipment to

eliminate waste codes

• Manifests

• Exception reports

• Test results 

• Records of past

management practices

• Records of storage

yard cleanup

• Documentation if any

past decontamination

of equipment to

eliminate waste codes

None

Personnel Training Formal classroom training

with annual updates

Employees must be

familiar with waste handling

and emergency procedures

relevant to their position

None

*Generators of between 100-1000Kg hazardous waste per calendar month (small quantity generators) who utilize drip pads must

comply with the standards for large quantity generators for the management of wastes on drip pads. This means that small quantity

generators can only accumulate hazardous waste for 90 days. This exception does not apply to the management of drummed

wastes, which are still subject to the 180-day accumulation time.

**Although Federal RCRA regulations do not specifically require conditionally exempt small quantity generators to comply with the

Subpart W drip pad standards, owners/operators of these facilities should note that any hazardous waste that is allowed to

accumulate on the ground (i.e., allowed to drip off of a charge and onto the ground in the storage yard) can be considered illegal

disposal of hazardous waste and subject to enforcement action. Therefore, it is advisable that conditionally exempt generators

manage their process in a manner that does not allow preservative or waste to contact the ground. 

Land Disposal

Restrictions

The RCRA Land Disposal Restrictions (LDR) require that hazardous

waste must meet specified treatment levels in order to be disposed of on

the land. An example of land disposal is the placement of wastes into a

landfill or lagoon. EPA has assigned each waste code identified under

RCRA a specific treatment standard that must be met before land

disposal can occur. Treatment standards can be expressed in two ways:

(1) as a specific technology (e.g., combustion, vitrification) that must be

applied to the waste in order to meet the standard, or (2) as specific

concentration levels. Facilities managing wastes with treatment standards

expressed as concentration levels may perform any type of treatment on

the waste stream to achieve the standard (keep in mind however, that a

generator cannot perform thermal treatment, such as incineration or

combustion, unless they obtain a RCRA permit). EPA does not allow the

dilution of hazardous waste to meet LDR treatment standards.
June 19, 1996

RCRA Overview Section 3 - 21

Wastes which do not meet treatment standards cannot be land disposed

unless EPA has granted a variance, extension, or exclusion for a particular

waste stream. Also, certain newly identified wastes (those identified on

or after November 8, 1984) have not yet been assigned treatment

standards. This is because EPA needs time to determine the best methods

available to treat these wastes in order to establish treatment standards.

Until a treatment standard has been developed, these wastes will not be

subject to LDR. Certain F-listed wastes from the wood preserving

industry (i.e., F032, F034, and F035) are among the wastes for which

EPA has not yet identified treatment standards. Until these treatment

standards are finalized, these wood preserving wastes are not subject to

LDR treatment standards. In addition, other wastes generated in the wood

preserving industry, such as K001, already have treatment standards.

K001, which is described in the listing as bottom sediment sludge from the

treatment of wastewaters from wood preserving processes that use

creosote and/or pentachlorophenol, does have an established numerical

treatment standard.

Generators and TSDFs managing hazardous wastes that are subject to

LDR have specific notification, certification, waste analysis, and

recordkeeping requirements. Similar to a hazardous waste manifest, LDR

notification and certification paperwork helps hazardous waste handlers

and EPA ensure that wastes are being properly treated before land

disposal.

Waste Subject to

LDR Requirements

Generators are responsible for determining whether their waste is subject

to LDR. This is accomplished by either testing the waste or by applying

generator process knowledge. If a waste is subject to LDR but does not

meet the applicable treatment standards, generators must provide written

notification to the TSDF to which the waste is being sent. Although there

is no specific LDR notification form, EPA does require specific

information to be included in the notice, including:

• EPA hazardous waste code

• Identification of the waste as a wastewater or non-wastewater

• Manifest number of the shipment

• Waste analysis information (if available)

• For certain specified wastes, any additional hazardous constituents

present in the waste.

If an LDR waste does meet applicable treatment standards, the generator

must certify to the receiving TSDF that the waste meets the required
June 19, 1996

RCRA Overview Section 3 - 22

treatment standards. Generators must keep a copy of all notifications and

certifications for at least five years.

Generators may treat their waste on-site to meet LDR treatment

standards. To do so, they must first develop a written waste analysis plan

(WAP). The WAP must justify the frequency of testing based on a

detailed analysis of a representative sampling of the waste, and contain

information necessary for proper treatment of the waste. Generators who

perform on-site treatment of hazardous waste that is unrelated to LDR

treatment standards are not required to develop a WAP.

RCRA Permitting Permits are an essential part of the RCRA Subtitle C program. RCRA

requires facilities that treat, store, or dispose of hazardous waste to obtain

an operating permit. A permit establishes site-specific administrative and

technical hazardous waste management standards to which a TSDF must

adhere. 

Permit Exemptions There are limited circumstances under which a facility can treat, store, or

dispose of hazardous waste without a permit:

• Large quantity generators storing hazardous waste on site for less

than 90 days, and small quantity generators storing hazardous waste

on site for less than 180 days

• Owners/operators of totally enclosed treatment facilities,

wastewater treatment units, and elementary neutralization units

• Persons engaged in containment activities during an emergency

response (e.g., spills, accidents)

• Owners/operators of solid waste disposal facilities handling only

conditionally exempt small quantity generator wastes.

Any facility that does not qualify for a permit exemption and that treats,

stores, or disposes of hazardous waste must obtain a RCRA permit.

Because treatment, storage, and disposal generally involve several

different types of units and multiple activities, the permitting regulations

impose requirements far more extensive than those imposed upon a

generator. As a result, many facilities in the wood preserving industry

have made a concerted effort to maintain generator status to avoid having

to apply for and adhere to the requirements of a permit. In light of recent

waste minimization efforts, this has become increasingly easier to

accomplish.
June 19, 1996

RCRA Overview Section 3 - 23

Permitting 

Standards

RCRA permitting standards consist of both general TSDF standards as

well as unit-specific standards. The general RCRA TSDF standards

require facilities to:

• Conduct detailed chemical and physical analyses of waste managed

at the facility

• Install security measures to protect human health, safety, and the

environment

• Develop and conduct a written facility inspection plan

• Ensure that facility personnel are trained to handle any hazardous

waste with which they may come into contact

• Properly manage all wastes to minimize the chance of ignition,

reaction, or explosion

• Comply with standards prohibiting the siting of a facility in areas

prone to flooding or seismic activity

• Develop emergency preparedness and contingency plans

• Comply with general manifesting, recordkeeping, and reporting

requirements.

All new facilities requiring a RCRA permit must apply for, and receive, a

permit before construction of the facility can begin. Owners/operators of

existing facilities must operate under RCRA's interim status standards

while seeking a permit or awaiting permit approval by EPA. With few

exceptions, RCRA's interim status standards are very similar to the

permitting standards.

Permit Applications RCRA permit applications are lengthy and comprehensive, consisting of

two parts: Part A and Part B. Both parts of the application provide EPA

with the information necessary to establish site-specific requirements. The

Part A application is submitted on Form 8700-23, and consists of basic

facility information such as the name, mailing address, and location of the

facility. The Part B application is the more complex, narrative part of the

permit application in which the applicant describes, in great detail, the

types of wastes that will be managed at the facility, precautionary

measures that will be taken to protect human health and the environment,

and all waste analysis, facility inspection, and contingency plans that will

be part of everyday activities of the facility. 

Once EPA receives this information, the application is reviewed,

presented for public comment, then approved or denied. All RCRA

permits are effective for a fixed term, not to exceed ten years. At that

time, the permit may be modified, reissued, or terminated.
June 19, 1996

RCRA Overview Section 3 - 24

Wood Preserving

Facilities and Permits

The process of obtaining a RCRA treatment, storage, and disposal permit

is difficult and lengthy, sometimes taking two years or more to complete.

Wood preserving facilities can, and often do, avoid the need to obtain a

RCRA permit by maintaining their permit-exempt status as a hazardous

waste generator. To do this, a facility must ensure that any waste

generated at the facility is removed and sent to a permitted or interim

status TSDF within the appropriate time frame (within 90 days for large

quantity generators and within 180 days for small quantity generators).

Because most wood preserving facilities do not generate large volumes of

waste, the majority of facilities do not find it difficult to remain exempt

from permitting requirements.

Closure 

Requirements at

Permitted Facilities

All hazardous waste management facilities eventually cease their treatment,

storage, or disposal activities. When ceasing operation, these facilities

must be closed and maintained in a way that ensures that they do not pose

a future threat to human health and the environment.

Closure regulations can be divided into two parts: general closure

standards and unit-specific standards. General closure standards apply to

all TSDFs entering into closure. Unit-specific standards address the

specific types of waste management units regulated under RCRA. Both

general and unit-specific standards must be satisfied to complete closure

activities. The maximum time allowed to complete closure after the unit

has received its final volume of waste is 180 days. Extensions to this 180-

day time period may be granted under certain circumstances by the EPA

Regional Administrator. All TSDFs must submit closure plans explaining,

in detail, how the facility will achieve the closure standards. Permitted

facilities must submit this plan with their Part B permit application. Interim

status facilities must have written closure plans on-site six months after

they become subject to the RCRA TSDF standards. 

Each closure plan must:

• Describe how each hazardous waste management unit at the facility

will be closed

• Estimate the maximum inventory of hazardous waste that will be onsite during the facility's operating life

• Describe closure methods necessary to remove and manage waste

present at the facility

• Describe any other steps necessary to achieve complete closure

• Contain a schedule of closure dates, including the amount of time

each closure activity will take
June 19, 1996

RCRA Overview Section 3 - 25

• Contain an expected date of final closure.

Post-Closure 

Requirements

Owners/operators who cannot "clean close" their facility by removing or

decontaminating all equipment, structures, and soils must also enter into a

period of post-closure care to prevent or control any future releases into

the environment. Post-closure is normally a 30-year period after closure

during which owners/operators must conduct groundwater monitoring and

maintenance activities to prevent releases. Facilities entering into postclosure must obtain a post-closure permit, and must also submit a postclosure plan to the EPA Regional Administrator describing how these

activities will be conducted.

Closure of Wood

Preserving Facilities

Wood preserving facilities that maintain generator status under RCRA are

subject to limited closure requirements. Large quantity generators must

close their accumulation units in a manner that minimizes or eliminates

post-closure release of hazardous waste into the environment, and must

dispose of or decontaminate equipment, structures, and soils at the facility.

Small quantity generators are not subject to generic closure requirements;

instead, small quantity generators must comply with applicable unitspecific closure requirements contained in the regulations. For example,

at closure, all accumulated hazardous waste and residues must be

removed from drip pads, treatment equipment, discharge equipment,

discharge control equipment, and discharge confinement structures. Small

quantity generators accumulating hazardous waste in tanks must also

comply with the appropriate tank closure requirements. 

Note: Small quantity generators accumulating hazardous waste on

drip pads must comply with the regulations applicable to large

quantity generators. Thus, they are subject to the general closure

requirements applicable to large quantity generators discussed

above.

Hazardous wastes generated from closure activities must be handled

according to applicable RCRA regulations. EPA has not established

specific Federal cleanup levels to verify "clean closure." Many States,

however, have established risk-based cleanup levels depending upon

projected land use at the facility. Thus, facilities must work closely with

their implementing agency to determine specific levels of decontamination

that will ensure the protection of human health and the environment.
June 19, 1996

RCRA Overview Section 3 - 26

Underground Storage

Tanks

RCRA's Underground Storage Tank (UST) program establishes a

comprehensive regulatory scheme for the management of USTs storing

petroleum and hazardous substances as defined under CERCLA. The

regulations establish minimum standards for new tanks and require

owners/operators of existing tanks to either upgrade, replace, or close

them according to the regulations.

The regulations are divided into two parts. The first part contains technical

requirements designed to reduce the chances of releases from USTs,

detect leaks and spills when they occur, and secure prompt cleanup in the

event of a release. The second part of the UST regulations consists of

financial responsibility requirements to ensure that, in the event of a spill or

leak from an UST, a facility will have the financial resources to pay for

cleanup and compensate any third parties involved. The financial

responsibility requirements apply only to USTs containing petroleum.

Most wood preserving facilities are not subject to the UST regulations; in

fact, the definition of "regulated substance" as it applies to the UST

program specifically excludes RCRA hazardous wastes. This is because

RCRA already has standards regulating the management of tanks

containing hazardous waste, whether underground or above ground. As

a result, tanks accumulating hazardous waste at a wood preserving facility,

even if underground, are not subject to the UST regulations. If, however,

a wood preserving facility does have an underground storage tank

(defined as a tank system whose volume is 10 percent or more below the

surface of the ground) on-site that contains petroleum or hazardous

substances as defined under CERCLA, it may be subject to the UST

regulations. 

Although there are no Federal RCRA standards for the management of

products in aboveground tanks, States may have established such

requirements. 

State Authorization The RCRA program grants certain States authorization to implement the

Federal hazardous waste regulations. To receive authorization, States

must demonstrate to EPA that their regulatory program is equivalent to

Federal authority, consistent with the Federal program, and at least as

stringent as the Federal regulations. Following such authorization, State

regulations operate in lieu of the Federal program in that State.

State authorization can be divided into two major categories: the "base

program" and "revisions." Before States can implement any part of the

Federal RCRA regulations, they must first obtain base authorization, which
June 19, 1996

RCRA Overview Section 3 - 27

allows a State to implement the fundamental requirements of the RCRA

program (generally anything published prior to April 1, 1983), such as

generator standards, hazardous waste identification standards, and basic

permitting provisions. For those States that do not have base

authorization (currently this list includes Iowa, Hawaii, Alaska, and some

U.S. territories), EPA implements the entire hazardous waste management

program.

Once a State receives base authorization, it must continue to revise its

program to incorporate frequent revisions to the RCRA regulations to

retain its authorized status. Because revisions to the Federal hazardous

waste management program consist of hundreds of individual rulemakings,

EPA has segmented the Federal program into different groups, or

clusters. A State may not incorporate clusters of rules into its program

until it receives base authorization. 

Note: Individual States may incorporate provisions into their own

programs that have no counterpart in the Federal program. These

additional elements of a State's program are not considered to be

part of the Federal RCRA program, and are not subject to State

authorization procedures.

Most States are not authorized for all clusters of hazardous waste

revisions. Therefore, the status of rulemakings that a State has not "picked

up" (been authorized for) depends on the statutory authority upon which

those rulemakings are based. For example, some rulemakings will be

effective immediately in all States, regardless of the rules' authorization

status in that State. Other rulemakings, however, must be picked up by

an individual State before they can become effective in that State. A

discussion of this aspect of State authorization is found below.

Within the State authorization program, it is important to distinguish

between those rulemakings that are published as a result of original RCRA

language (i.e., from statutory language from 1976), and those published

pursuant to the Hazardous Solid Waste Amendments of 1984 (HSWA).

Prior to the enactment of HSWA, a State with final authorization

administered its hazardous waste program entirely in lieu of the Federal

program. Federal requirements no longer applied in the authorized State,

but were incorporated into the individual State's hazardous waste

program. When new, more stringent requirements were enacted, the

State was obligated to enact equivalent authority within specified time

frames. New Federal requirements did not take effect in an authorized

State until the State adopted the requirements as State law. Some Federal

rules are still issued based on the original pre-HSWA authority, and
June 19, 1996

RCRA Overview Section 3 - 28

Exhibit 8

Relationship Between State Authorization Status and HSWA/Non-HSWA Rulemakings

State Authorization Status

Statutory Basis for Rulemaking

Non-HSWA HSWA

Authorized State (authorized for

base RCRA program)

Effective date = Date when State

became authorized for rule,

implementation of rule by State

Effective date = Date of rule, EPA

implements until State adopts rule

Unauthorized State (no

authorization for base RCRA

program)

Effective date = Date of rule,

implementation of rule by EPA

Effective date = Date of rule,

implementation of rule by EPA

become effective in authorized States (those States which have been base

authorized for rules published prior to April 1, 1983) only when the State

adopts the provisions as State law. These rules are known as "nonHSWA" rulemakings.

In contrast, HSWA of 1984 amended RCRA and changed the State

authorization regulations. Under the revised program, any new

requirements or prohibitions imposed by HSWA take effect immediately

in all States upon the effective date of the standards, regardless of a

State's authorization status. In those States that do not have base

authorization, EPA will implement the program until the State is granted

the authority to do so. Rulemakings that are developed pursuant to

HSWA are called HSWA rulemakings. Exhibit 8 illustrates the difference

between HSWA and non-HSWA rulemakings. The difference between

HSWA and non-HSWA rulemakings is important in determining the status

of wood preserving wastes in a particular State.
June 19, 1996

RCRA Overview Section 3 - 29

Additional information is available on the subjects discussed above: 

• For general information on RCRA, refer to EPA's RCRA Orientation Manual, 1990 Edition,

EPA/530-SW-90-036.

• For information on the specific regulations, consult the following sections of the Code of Federal

Regulations:

- Definition of Solid Waste — 40 CFR §261.2

- Definition of Hazardous Waste — 40 CFR §262.11

- Characteristic Waste — 40 CFR §§261.20-261.24

- Listed Waste — 40 CFR §§261.31-261.33

- Hazardous Waste Mixtures — 40 CFR §261.3(a)(1)(iv)

- Derived-From Hazardous Waste — 40 CFR §261.3(c)(2)

- Hazardous Waste Counting — 40 CFR §261.5

- Generators of Hazardous Waste — 40 CFR Part 262

- Accumulation Time/Storage Limits — 40 CFR §262.34 

- Satellite Accumulation — 40 CFR §262.34(c)

- Conditionally Exempt Small Quantity Generators — 40 CFR §261.5

- EPA Identification Numbers — 40 CFR §262.12

- Pre-Transport Requirements — 40 CFR §§262.30-262.33; 49 CFR Parts 172, 173, 178, and

179

- Manifest Requirements — 40 CFR §262.20

- Recordkeeping/Reporting Requirements — 40 CFR §§262.40-262.43

- Hazardous Waste Under RCRA — 40 CFR Part 261

- Permitting Under RCRA — 40 CFR Part 270

- Exemptions From Permitting — 40 CFR §270.1(c)(3)

- Exemptions from Definition of Solid Waste/Hazardous Waste — 40 CFR §261.4

- RCRA General TSDF Standards — 40 CFR Part 264/265, Subparts A-H

- Permit Application Process — 40 CFR Part 270, Subpart B

- Land Disposal Restrictions — 40 CFR Part 268

- LDR Notification Requirements — 40 CFR §268.7

- Waste Analysis Plans — 40 CFR §268.7(a)(4)

- Closure and Post-Closure — 40 CFR Parts 264/265, Subpart G §262.34 (generator closure)

- Underground Storage Tanks (USTs) — 40 CFR Part 280

- State Authorization — 40 CFR Part 271.

• For more information on EPA's contained-in policy, consult the regulatory interpretive

correspondence dated June 16, 1989, written from Cannon to Jorling. This memorandum is also

a part of the RCRA Permit Policy Compendium, #9441.1989(30).

• For more information on episodic generation and hazardous waste counting, consult the March

24, 1986, Federal Register (51 FR 10146; March 24, 1986).

• For more information on the Toxicity Characteristic Leaching Procedure (TCLP), consult the

March 29, 1990, Federal Register (55 FR 11798; March 29, 1990) and the Technical Assistance

Document for Complying with the TC Rule and Implementing the Toxicity Characteristic

Leaching Procedure (TCLP) (Revised May 1994) EPA, 902-B-94-001.
RCRA Waste Section 4 - 1

SECTION 4

RCRA WASTE GENERATED BY WOOD PRESERVING

Introduction The wastes produced from the wood preserving processes discussed in

Section 2 have been the subject of substantial regulatory action in recent

years. In 1990, EPA issued final regulations that specifically listed wood

preserving wastes from facilities that use chlorophenolic formulations,

creosote formulations, and inorganic preservatives containing arsenic or

chromium. The types of wastes identified include wood preserving

wastewaters, process residuals, preservative drippage, and spent

preservatives. In addition to these specific identified wood preserving

wastes, wood preserving facilities can also generate other "listed" and

"characteristic" wastes depending on the processes and chemicals used.

Listed and characteristics wastes, as defined under RCRA, are discussed

in Section 3 of this Guide.

This section of the Compliance Guide discusses three general types of

hazardous waste generated by wood preserving facilities: wastewaters;

process residuals; and preservative drippage. It also discusses some of

the exclusions from RCRA that may apply to these wastes at various

stages of the wood preserving.

Health Concerns of

Wood Preserving

Wastes

Wastes from the wood preserving industry can be considered hazardous

because they are listed as a hazardous waste or they exhibit a

characteristic of hazardous waste. EPA has data demonstrating that

constituents found in wastes generated by the wood preserving process,

such as chlorophenolics, creosote, and inorganics (i.e., arsenic and

chromium) are systemic toxicants and/or carcinogens. Systemic toxicants

are constituents that may have long-term chronic effects other than cancer

or mutations. Carcinogens are constituents that have the potential to cause

cancer. Some of these wastes may also contain high levels of dioxins.

Given the high concentrations of these chemicals typically present in

wastes produced by the wood preserving industry, the potential for

harmful exposure to human if chemicals are mishandled, can be significant.

Potential for exposure is most likely to occur through contact with

contaminated groundwater or chronic occupational exposure.

For example, previous studies of pentachlorophenol have shown it to be

highly toxic to humans. Exposure to pentachlorophenol can cause contact

dermatitis, damage to vision, and upon ingestion, lung, liver, and kidney

damage. Inhalation of pentachlorophenol can result in acute poisoning,
June 19, 1996

RCRA Waste Section 4 - 2

Exhibit 9

Wood Preserving Process Inputs and Pollution Outputs

Material Input Air Emissions Process Waste Other Waste

Wood; water; carrier

oils; creosote;

inorganic formulations

of arsenic, chromium,

copper, zinc; pentachlorophenol;

borates; ammonium

compounds

Boiler emissions,

air-borne arsenic,

polycyclic organics,

penta-chlorophenol,

volatile organic

compounds from

carrier oils and

creosote

Dripped formulation

mixed with

rainwater, wash

down water,

detergent, kiln

condensate, contact

cooling water

Sump and retort

sludges, process

residuals including

discarded clothing and

gloves, banding, wood

stickers, saw dust and

splinters from the drip

pad, contaminated soils

from storage yard

clean-up

centering on the circulatory system with possible accompanying heart

failure. Other studies have also shown pentachlorophenol to be a

carcinogen. 

One of the most commonly used preservatives in the wood preserving

industry is chromated copper arsenate, or CCA. This formulation

contains water, arsenic acid, chromic acid, and copper oxide.

Overexposure to CCA can damage mucous membranes and tissues of the

respiratory system, or cause chemical burns on the skin or skin lesions.

Ingestion of large amounts of CCA may have more serious effects.

Chronic exposure to significant doses of CCA can lead to mental

confusion, loss of coordination, and impaired senses of touch, pain, and

temperature. CCA is also considered a possible carcinogen.

Due to these and other health concerns, EPA found it necessary to

specifically identify wood preserving wastes as hazardous under RCRA.

Exhibit 9 provides an overview of the material inputs and pollution outputs

from the Wood preserving process.

Wastewater Wastewaters produced during the wood preserving process that are

regulated under RCRA can be generated during various stages of wood

preserving operations.These include wastewater generated during steam

conditioning wood in treatment cylinders prior to applying preservative,

preservative formulation recovery and generation wastewater, water used

to wash excess preservative from the surface of preserved wood while
June 19, 1996

RCRA Waste Section 4 - 3

sitting on the drip pad, washdown water used to clean drip pads, and

condensate from kilns used to dry preserved wood.

Other operations resulting in the generation of wastewater include the

rinsing of drums, storage tanks, process areas, and equipment. In

addition, water, including rainwater, that accumulates on drip pads and

in retort sumps, and rainwater falling on or in the treatment cylinder and

work tank secondary containment areas, is also classified as hazardous

waste.

Most wastewater generated at wood preserving facilities is considered

hazardous waste under RCRA either because it is mixed with a listed

waste or because it exhibits a characteristic of hazardous waste. As a

result, many of the tanks and other units in which these wastes are

collected, stored, accumulated, treated, and/or disposed will be subject

to RCRA regulation (a more detailed explanation of regulations concerning

management of hazardous waste in tanks is provided in Section 6 of this

Guide).

Note: Many tanks or sumps that are used to accumulate or treat

wastewaters from wood preserving may, in fact, be excluded from

RCRA regulation. Wastewater treatment units subject to regulation

under the Clean Water Act are exempt from RCRA standards. As a

result, tanks and sumps used to collect wastewaters may not be

subject to any standards. Check with the appropriate State

hazardous waste agency to determine the applicability of this

exemption.

Much confusion exists as to which wastes generated at wood preserving

facilities should be counted. Whether wastewater is counted toward a

facility's generator status will depend on a number of factors. Specific

hazardous waste counting issues as they relate to the wood preserving

industry are discussed elsewhere in this section(See Exhibit 6, Hazardous

Waste Counting).

Note: Wastewater that does not come into contact with preservative

solutions is not regulated as listed waste under RCRA. Wastewaters

can, however, exhibit a characteristic of hazardous waste depending

on the hazardous constituents in the wastewater.

Process Residuals Materials such as sawdust, wood chips, splinters, equipment and parts,

tags, labels, sand, dirt, and stones, that are attached to wood when it

enters the retort are often washed off during the treatment process. These
June 19, 1996

RCRA Waste Section 4 - 4

materials can form a residue in the retort and may settle out of the

preservative solution elsewhere in the process (e.g., in work tanks, retorts,

or sumps). They may also be intentionally filtered out of the preservative

prior to reuse in the treatment process. Other process residuals include

discarded personal protective equipment (e.g., gloves, clothing, tyvec

suites, boots that have come into contact with preservative), used banding

(that is not being recycled), and wood stickers. All of these wastes are

considered process residuals and must be handled as hazardous waste

under RCRA if they have contacted listed wastes or if they exhibit a

characteristic of hazardous waste.

Determining exactly when these materials are generated for purposes of

making a hazardous waste determination and complying with appropriate

management standards can be complicated and site-specific. Where

process residuals are continually deposited at the bottom of a work tank

or sump, hazardous waste is not generated until the work tank/sump/pit

is cleaned out and the sludge is removed. At the time the sludge is

removed, owners/operators must determine whether the waste is

hazardous.

The generation of process residuals can be significantly reduced by

employing waste minimization practices at wood preserving facilities. For

example, by power washing incoming lumber or by accepting only clean,

high grade lumber for treatment, owners/ operators can minimize the

amount of hazardous process residuals generated.

Drippage and

Process Residuals

Preservative drippage and process residuals may also accumulate on drip

pads, in pathways over which treated wood is transported, and in treated

wood storage yards. This category of waste includes drippage of

preservative from treated wood, preservative that is washed off treated

wood by rainwater, and residuals from collecting and recycling

preservative that drips off or is washed off treated wood.

Note: Preservative that is washed off treated wood in storage yards

by rainwater is not specifically identified as a RCRA listed waste, but

it may exhibit a hazardous waste characteristic. In addition,

although the Subpart W drip pad standards do not apply to storage

yard drippage, drippage of excess preservative that occurs in storage

yards may be covered by the hazardous waste listings discussed

below if certain chemical formulations are used, and must be cleaned

up immediately in accordance with the facility's contingency plan for

storage yard drippage (for a more detailed discussion of EPA's

regulation of storage yards, see Section 6).
June 19, 1996

RCRA Waste Section 4 - 5

Contaminated

Clothing and Other

Materials

Personnel working at wood preserving facilities often produce

contaminated personal protective equipment (PPE) such as disposable

cover-alls, clothing, gloves, boots, and other materials (e.g., trash). These

items are commonly sent for disposal or to a laundering facility so they can

be cleaned and used again.

Contaminated materials that are sent for disposal must be handled as

RCRA hazardous wastes and manifested to a permitted or interim status

TSDF. Contaminated materials that are sent to a laundering facility should

be handled in a safe and protective manner. Owners/operators of wood

preserving facilities should ensure that the laundering facility is instructed

on safe handling procedures, that it segregates contaminated materials

from others, and that the laundering facility's POTW is aware of the

contaminated items and what kinds of chemicals they contain. This will

enable the operator of the laundering facility to make all necessary

arrangements to comply with Clean Water Act (CWA) requirements.

Hazardous Wastes

Generated by Wood

Preserving

Operations

There are several EPA-classified hazardous wastes that may be generated

during, or as a result of, wood preserving operations:

• F027 — discarded unused pentachlorophenol.

• F032 — wastewaters, process residuals, preservative drippage,

and spent formulations from plants that use or have used

chlorophenolic formulations. This listing applies to those facilities

using "penta" wood preserving formulations.

• F034 — wastewater, process residuals, preservative drippage, and

spent formulations from plants that use creosote formulations.

• F035 — wastewater, process residuals, preservative drippage, and

spent formulations from plants that use inorganic preservatives

containing arsenic or chromium.

• K001— bottom sediment sludge from the treatment of wastewater

from wood preserving processes that use creosote or

pentachlorophenol.

• U051 — discarded unused creosote.

• Characteristic Wastes — constituents included in the toxicity

characteristic that may be generated by the wood preserving

industry include arsenic (D004), chromium (D007), lead (D008),

pentachlorophenol (D037), and wastes containing cresols (D023,

D024, D025, D026). Wastes generated at wood preserving

facilities may also exhibit the characteristic of corrosivity (D002).

This is not an exhaustive listing of all possible waste codes that may
June 19, 1996

RCRA Waste Section 4 - 6

apply. Owners/operators must evaluate their specific waste

streams against the toxicity characteristic constituents.

• K035 — wastewater treatment sludges generated in the

manufacturing of creosote (this listing does not normally apply

to wood preserving facilities).

Wastes that meet any one of the above descriptions must be handled,

stored, and disposed of according to RCRA regulations.

Note: Most wood preserving facilities maintain tank farms where

preservative is stored before use. Although these tanks are not

holding hazardous waste, leaks from tanks and valves have the

potential to be classified as listed or characteristic wastes under

RCRA. For example, unused pentachlorophenol, when leaked, will

carry the waste code F027, while unused creosote will carry the

waste code U051. In addition, any chemical that is leaked or spilled

at a tank farm may exhibit a characteristic of hazardous waste.

Exhibits 10 and 11 illustrate the types of wastes typically generated by the

wood preserving industry. This exhibit is intended to give

owners/operators of wood preserving facilities a general idea of possible

hazardous waste codes being generated at a facility according to the type

of preservative used.
June 19, 1996

RCRA Waste Section 4 - 7

Exhibit 10

Codes of Hazardous Waste Generated at Wood Preserving Facilities

Preservative F03 F034 F03 K00 F02 D05

Toxicity

Characteristic(TC)*

Not Considered

Hazardous By US EPA

OIL-BORNE FACILITIES

Creosote T T T D023, D024,

D025,

Pentachlorophenol T T T D026

Copper Napthenate D037 T

WATER-BORNE FACILITIES

Ammoniacal Copper Arsenate

(ACA)

T

Chromated Copper Arsenate

(CCA)

T D004, D008

Oxine Copper D004, D008, D007

Ammoniacal Copper Citate

(CC)

Copper

Dimothyldithiocarbamate

(DDC)

T

Ammoniacal Copper Zinc

Arsenate (ACZA)

T

Acid Copper Chromate (ACC) T

Borates T

Ammoniacal Copper Quat

(ACQ)

T

Note: This chart contains only suggested hazardous waste codes under the toxicity characteristic. All of these presentations may

contain other hazardous constituents that would cause it to exhibit the TC for another hazardous constitutent.

* See 40 CFR §261.24 for a complete list of constituents identified under the toxicity characteristic.

** Facility is required to make a hazardous waste determination prior to disposal as non-hazardous waste (§262.11).
June 19, 1996

RCRA Waste Section 4 - 8

Exhibit 11

Wood Preserving Hazardous Waste Code Identification Table

LISTED HAZARDOUS WASTES TOXICITY CHARACTERISTICS WASTES***

Note: This general guidance may not be accurate in all

cases.

WASTE F032 F034 F035 K001 F027 U051 D002 D004 D007 D008 D023 D024 D025 D026 D037

Wastewater Treatment Unit Sludge

 penta X X

 creosote X X X X X

Dump Sump Sludge

 penta X X

 creosote X X X X X

 inorganics* X X X X X

Filter Sludge

 penta X X

 creosote X X X X X

 inorganics* X X X X X

Wastewater

 penta X X

 creosote X X X X X

 inorganics* X X X X X

Process Residuals**

 penta X X

 creosote X X X X X

 inorganics* X X X X X

Storage Yard Clean-up Material

 penta X X

 creosote X X X X X

 inorganics* X X X X X

Discarded Treated Wood End

User/Customer

 penta X

 creosote X X X X

 inorganics* X X

Discarded Unused Preservative (concentrate)

 penta X

 creosote X

 inorganics* X X X X

Tank Clean-out Bottoms

 penta X X

 creosote X X X X X

 inorganics* X X X X X

* Inorganic formulation of arsenic and/or chromium

** See process residual for examples

*** Not necessarily limited to these wastes

Note: The Toxicity Characteristic waste code apply only to those wastes that are not already covered by an F, or V waste code.
June 19, 1996

RCRA Waste Section 4 - 9

Exclusions from the

Definition of Solid

Waste

In order for a material to be considered a hazardous waste under RCRA,

it must first be classified as a solid waste. Several types of materials,

however, are expressly excluded from RCRA's definition of solid waste.

Because they are not considered solid wastes, excluded wastes cannot be

considered hazardous waste and are not subject to RCRA regulation.

Excluded wastes may include wood preserving wastes that are recycled

or reused in a manner consistent with normal product handling (e.g.,

directly returned to the treatment process). The eligibility of a particular

material for an exclusion will depend upon the part of the process from

which it is produced and the intended use of the material. 

Note: When evaluating the RCRA exclusions that may apply to the

reuse of spent wood preserving solutions, it is important to note that

wood preservative that is directly returned from the retort to storage

and mixture tanks for reuse, is not considered a waste under RCRA.

Any preservative that has not been absorbed by the wood may be

directly pumped back into the system and reused without ever

becoming subject to regulation. It is when the preservative is taken

out of this continuous process loop, either for reclamation or

disposal, that it becomes subject to regulation as a RCRA hazardous

waste (e.g., when it is on the drip pad, which is a hazardous waste

management unit and is not considered by EPA to be part of a closed

loop). Owners/operators are strongly encouraged to verify the status

of a particular waste stream with the appropriate State hazardous

waste agency.

Closed Loop 

Recycling

Closed loop recycling involves processes where secondary materials are

reclaimed and returned to the original process from which they were

generated, provided a number of conditions are met. This exclusion

requires that only tank storage be used, and that the entire process,

through completion of reclamation, be closed (e.g., there must be no

potential for releases into the environment).

Wastes generated in the wood preserving industry will not usually qualify

for the closed loop recycling exclusion. This is because a large portion of

the waste generated during the treatment process is generated when

excess preservative and process residuals accumulate on drip pads. EPA

has determined that drippage and residuals that "escape" the wood

preserving process (i.e., wastes that accumulate on drip pads) are not

eligible for this exclusion because drip pads are not considered tank

storage. 
June 19, 1996

RCRA Waste Section 4 - 10

It is possible that other wastes generated during the wood preserving

process (e.g., wastes that are not accumulated on drip pads) could qualify

for this exclusion. For example, wastes from the treatment cylinder that

are pumped back into the product holding tank, but that need some

reclamation before being returned to the tank (e.g., filtration or separation)

may meet this exclusion. This is an important exclusion to consider if

excess preservative that is removed from the treatment cylinder following

wood treatment must be reclaimed in any way before reinsertion back to

the process tank. Normally, any spent material, such as preservative

solution that cannot be used further without some reprocessing, and which

is reclaimed, is considered a solid waste and a hazardous waste under

RCRA until the point that it is reclaimed and can be used as a product

again. Owners/operators who utilize the closed loop exemption will not

have to classify these materials as hazardous waste, and will not have to

"count" these wastes each month toward their generator status.

Direct Use/Reuse RCRA also contains a specific exclusion from the definition of solid waste

for materials that are recycled through direct use or reuse. This

exclusion involves the return of a chemical to the original process from

which it was generated as a substitute for a raw material feedstock. If the

material is delivered to the process and does not require or undergo any

reprocessing to make it suitable for reuse, it may fit this exclusion. In other

words, the material must be able to be directly reinserted back into the

process without any intermediate reclamation or accumulation. For wood

preservers,reclamation can include simple filtration. This exclusion is

different from the closed loop exemption in that there can be no

reclamation of the material prior to reinsertion into the process and the

exclusion does not require a closed system. Owners/operators are

strongly encouraged to verify the status of a particular waste stream with

the appropriate State agency.

Reclaimed Spent 

Wood Preserving

Solutions

To encourage the sound recycling of reclaimed products, EPA has

exempted the following materials from the definition of solid waste:

• Spent wood preservative solutions that have been reclaimed and

are reused for their intended purpose

• Wastewaters from the wood preserving process that have been

reclaimed and are reused to treat wood.

Under this exclusion, spent wood preserving solutions that have been

reclaimed and are reused for their original intended purpose are not

considered solid or hazardous wastes under RCRA. Thus, preservative
June 19, 1996

RCRA Waste Section 4 - 11

that is reclaimed and then pumped from the retort back into the holding

tank for storage and reuse as a preservative is not regulated under RCRA.

Similarly, wastewater from the wood preserving process that is

"reclaimed" and reused to treat wood is also exempt from regulation. 

Note: This exclusion does not provide a blanket exclusion for these

materials from their point of generation through reclamation. Up

until the time the preservatives or wastewaters are reclaimed, the

materials are considereds, and must be managed as, solid and

hazardous wastes.

The exclusions discussed above are very complex. Determining whether

materials generated at a particular facility are, in fact, excluded from the

definition of solid waste is dependent upon a number of site-specific

variables. When determining whether one of these exclusions may apply

to a specific waste stream, owners/operators may begin the assessment

by using the following general rule of thumb. Materials that do not

come into contact with a hazardous waste drip pad, and that are

directly reinserted back into the holding tank without being

reclaimed first, are not considered hazardous wastes under RCRA,

unless sent for disposal. Material that is collected on the drip pad

and sent for disposal is a hazardous waste. Preservative solution

that is collected on the drip pad and reclaimed before being used as

a wood preservative is a solid and hazardous waste up until the

point it is reclaimed. Once reclaimed, these materials are no longer

hazardous waste under RCRA.

Owners/operators should refer to their implementing hazardous waste

agency for case-by-case analyses of difficult or questionable regulatory

scenarios. Exhibit 12 is a decision tree for identification of hazardous

waste that can be used by owners/operators to assist in making hazardous

waste determinations.
June 19, 1996

RCRA Waste Section 4 - 12

Is Chlorophenolic

formulation (e.g., Penta)

Now Used?

Is Waste Unused

Penta Formulation?*

Waste is F027 Yes

Yes

No

Has Chlorophenolic

Formulation

Ever Been Used?

Is Creosote

Now Used?* Waste is F034

Yes Yes

No No

Is Chromium/Arsenic

formulation Now Used?* Waste is F035 Yes

No

Does Waste Exhibit

a Characteristic?

(Toxicity, corrosivity,

reactivity, ignitability)

Waste is Characteristic

and F032**

Yes

Is Creosote

Now Used?

Is Waste Unused

Creosote?

Yes

No

Is Chromium/Arsenic

Formulation Now Used? Waste is F035

Yes

No

Does Waste Exhibit

a Characteristic?

Waste is a RCRA**

Characteristic

Hazardous Waste

Yes

No

Not a RCRA

Hazardous Waste

Waste is F032

No

Waste is F034

No

Waste is U051

Yes

Waste is F032

No

* Sludges from creosote and/or penta wastewater treatment units

are K001 waste.

** Arsenical-treated wood that is discarded by end users and that

exhibits only hazardous waste characteristics D004-17 is excluded

from RCRA regulation

Note: Possible F032 waste code deletion if equipment is cleaned

according to procedures specified in §261.35. Also see: 57

Federal Register, December 24, 1992, p61493 - Provisional

Elimination of F032 Waste Code

Exhibit 12

Hazardous Waste Identification for the Wood Preserving Industry
June 19, 1996

RCRA Waste Section 4 - 13

Wood Preserving

State Authorization

Issues

As discussed in Section 4, the status of a particular rulemaking in a State

depends on the State's authorization status for that rule. If a rulemaking

is promulgated pursuant to original RCRA (non-HSWA) language, the

rule will not become effective in a "base" authorized State until that State

adopts the rule. Rulemakings promulgated pursuant to HSWA of 1984,

however, will be effective immediately in all States until each State adopts

the rule. Until States are able to do so, EPA will implement the HSWA

provisions. The wood preserving industry is a good example of how both

HSWA and non-HSWA provisions can work in conjunction with one

another. For example, certain portions of the final wood preserving rule

(55 FR 50450; December 6, 1990) were promulgated under HSWA

authority, while others were promulgated pursuant to non-HSWA

authority. The implications of this are discussed below.

Hazardous waste codes F032, F034, and F035 were promulgated

pursuant to different statutory authorities. The F032 listing is a HSWA

provision, and is applicable in all States, regardless of whether they are

"base" authorized or not. Since the F034 and F035 listings are nonHSWA provisions, these listings are only effective in those States that are

not authorized for the "base" RCRA program, and in those States that

have incorporated the listings into their State programs and received EPA

approval for such revisions. On the other hand, the F034 and F035

listings are not applicable in base authorized States that have not yet

modified their State programs to include these listings. In order to become

authorized for these listings, a State must "pick up" the rulemaking which

promulgated the listings. In this particular case, a State would need to

become authorized for the December 6, 1990, Federal Register which is

the final rulemakings for these listings. Exhibit 13 illustrates which States

have "picked up" the wood preserving rule, and which have not.
June 19, 1996

RCRA Waste Section 4 - 14

Guam

Note: The December 6, 1990 Federal Register is not the only source of information pertaining to wood

preserving wastes and hazardous waste drip pads. it is, however, the most significant rulemaking

concerning wood preserving and subpart W drip pads. Any State that is authorized for this rule is

authorized for the majority of requirements. This map will give owners/operators a very good indication of

which States are authorized for the rule. For information on other rulemakings pertaining to the wood

preserving industry, please consult the appropriate State hazardous waste agency.

Authorized for Wood Preserving Listing/Final Drip Pad Standards

Adopted the December 6, 1990, Federal Register, but not before obtaining

final authorization for a particular rulemaking. Thus States must first

adopt the regulations as part of that State’s hazardous waste program.

Once the State has adopted the standards, Federal authorization can be

achieved.

Possibly authorized for other rules, but not for 12/6/90 Federal Register

Exhibit 13

State Authorization/Delegation of RCRA Wood Preserving Rules

Note: It is important to remember that wood preserving wastes may carry

waste codes other than F032, F034, and F035. For example, a wood

preserving waste could exhibit the toxicity characteristic for lead (D008).

Exhibit 12 focuses on the wood preserving rule because it promulgates the

listings most commonly generated at wood preserving facilities, as well as

the drip pad standards themselves. Thus, a State that has been authorized

for this rule is authorized for both the wood preserving listings and the

Subpart W standards. To determine the status of this waste stream in a
June 19, 1996

RCRA Waste Section 4 - 15

particular State, an owner/operator must check to see if that State is,

authorized for the rule which promulgated the toxicity characteristic

(March 27, 1990, Federal Register. The same type of determination

must be made for other wastes generated at the facility.

The authorization status of hazardous waste drip pads is directly tied to

that of the wastes being accumulated on such drip pads. For example,

EPA considers the drip pad standards to be HSWA requirements when

used in conjunction with the F032 listing. Thus, the Subpart W provisions

for F032 drip pads will be effective on the same date as the F032 listing,

and will be administered by EPA until the State picks up the rule. For

F034 and F035 drip pads, however, the Subpart W standards are not

immediately effective in base authorized States since these requirements

were not promulgated pursuant to HSWA authority. Therefore, the

permitted and interim status standards for drip pads associated with F034

and F035 wastes will only become effective in base authorized States

when F034 and F035 become hazardous wastes in those States, and

when those States are authorized for the drip pad standards.

Note: Many wastes generated on drip pads may also exhibit the

toxicity characteristic (TC). The TC, promulgated pursuant to

HSWA authority, is effective in all States and implemented by EPA

until each State is able to adopt the rule and implement the program.

As a result, drip pads used to manage TC wastes must meet the

Subpart W standards. This is identical to the authorization scenario

for F032 wastes.

State authorization of wood preserving wastes and Subpart W drip pads

is a particularly difficult issue, requiring an in-depth understanding of

RCRA's State authorization program. To accurately assess the status of

a waste stream in a particular State, owners/ operators must contact the

appropriate State hazardous waste agency.

Pollution Prevention

Opportunities

The best way to reduce pollution is to prevent it in the first place. Some

companies have creatively implemented pollution prevention techniques

that improve efficiency and increase profits while at the same time

minimizing environmental impacts. This can be done in many ways such

as reducing material inputs, re-engineering processes to reuse byproducts, improving management practices, and employing substitution of

toxic chemicals. Some smaller facilities are able to actually get below

regulatory thresholds through aggressive pollution prevention policies. 
June 19, 1996

RCRA Waste Section 4 - 16

In order to encourage these approaches, this section provides both

general company-specific descriptions of some pollution prevention

advances that have been implemented within the wood preserves industry.

While the list is not exhaustive, it can be used as the starting point for

facilities interested in beginning pollution prevention projects. The activities

described in this section do not necessarily apply to all facilities. Facilityspecific conditions must be carefully considered when pollution prevention

options are evaluated, and facilities must examine how each option affects,

air, land, and water pollutant releases.

Water-borne preservatives produce less waste than oil-borne

preservatives because process wastewater is reused rather than

discharged. In addition, well designed treatment plants, good treatment

practices, effective housekeeping, and employee training also help reduce

waste at the source.

Well designed treatment plants may have enclosed treatment buildings,

covered drip pads with liners, automatic lumber handling systems,

centralized tank farms with spill containment, and air ventilation systems.

Facilities can reduce waste by using drip free trams and dedicated drip

pad fork lifts that do not track debris into the drip pad. Some facility

operators prevent significant spills from incomplete door seals by using a

remote TV monitor to quickly discover and correct door leaks. Plants can

also be designed to minimize mist or droplet emissions from cylinders and

work tanks through the use of air exchange systems and cylinder and tank

venting.

Treatment practices are also important for preventing pollution. Ensuring

that wood stock is clean prior to treatment will prevent dirt, sawdust, and

other debris from accumulating in the treatment system. To prevent debris

buildup, wood can be covered during shipment and/or power-washed

before it enters the treatment plant. Strip pumps may be installed to

continuously return residual chemical solutions to the work tank, resulting

in less dripping when the cylinder doors are opened. If treating cylinders

are tilted slightly away from the drip pad, there is also less spillage when

cylinder doors are opened. 

CCA facility operators can reduce the amount of preservative that is

washed off by rainwater in the storage yard by ensuring that chemical

fixation has occured before a charge is moved off of the drip pad or out

from under an enclosure.

Housekeeping is an integral part of waste minimization efforts. All tanks,

mixing systems, treating cylinders, drip pads, and spill containments should
June 19, 1996

RCRA Waste Section 4 - 17

be inspected regularly for leaks. Drip pads and collection areas should be

kept clean. Storage yards should be inspected daily, and any drippage

should be cleaned up within 24 hours. 

Several other preservatives have been proposed as alternatives to

traditional preservatives. For example, wood can be treated with borates

using both pressure and non-pressure processes. However, because they

are highly susceptible to leaching, borates cannot be used to preserve

wood that will be in contact with the ground or exposed to the weather

(e.g., decking).

Ammoniacal copper/quarternary ammonium (ACQ) is another proposed

alternative. Initial above-ground field test data show that ACQ is effective

for softwood and hardwood protection. Other alternative preservatives

may include copper-8-quinolinolate (Cu8), copper naphthanate, zinc

naphthanate, quarternary NH4 compounds (QAC), and zinc sulfate.

Treatment processes may vary in their ability to minimize waste. For

example, the empty-cell process uses less carrier oil than the full-cell

process for oil-borne preservatives. The modified full-cell treatment

reduces the uptake of treating solution and minimizes the amount of

dripping from wood that has been treated with water-borne preservatives.

Pollution Prevention

Case Study

Perry Builders, Inc. employs 20 people at its pressure wood preserving

manufacturing facility. Perry Builders recognizes that each wood treater

has an important responsibility in properly handling and disposing of the

wastes it produces, and is committed to meeting this challenge. Perry uses

a water-borne chemical preservative, chromated copper arsenate, to treat

lumber, plywood, timbers, and other wood products for decks, fences,

and other outdoor uses. Hazardous waste results when sawdust, wood

chips, and dirt comes in contact with the preservative.

Perry has successfully minimized its hazardous waste generation by 80

percent in two years with the implementation of a low-cost waste

minimization program. In 1987, Perry generated 15 drums of hazardous

waste with a disposal cost of $2,380. By 1989 Perry reduced its disposal

cost to $310 by generating only two drums.

This reduction was achieved by changing both equipment and processes

to achieve a fully integrated closed system in which the application,

receipt, transfer, and storage of the preservative takes place in a contained

area.
June 19, 1996

RCRA Waste Section 4 - 18

The goal is to apply the preservative to the wood while minimizing the loss

of the preservative as a waste. By holding the lumber in the treatment

chamber longer to allow drippage, and by using a vacuum pump to further

dry the lumber, the treatment solution remains in the chamber and does not

come into contact with scrap material and dirt. A roof over the area

housing the treated lumber prevents runoff during rainfall. As an incentive

to ensure adequate drying time, employ pay is based on hourly wages

rather than the amount of lumber treated.

Perry Builders estimates that the cost of the vacuum pump, the roof, and

the increased drying time will be recovered in five years through reduced

disposal costs. There is also another economic benefit — since the drier

lumber weighs less, more footage of lumber can be shipped on each truck,

reducing freight costs.

Frequently Asked

Questions

The following are frequently asked questions concerning regulatory

scenarios encountered at wood preserving facilities. In every case, it is

imperative that owners/operators consult the appropriate RCRAdelegated agency for final regulatory determinations. Responses to these

questions assume that the facility uses creosote, pentachlorophenol, or

inorganic arsenic or chromium, and that it has the potential to generate

RCRA hazardous wastes.

Question 1

Counting Hazardous

Waste

• At what point is drippage that is returned to the treatment

chamber from the drip pad no longer considered a solid and

hazardous waste?

Assuming the drippage is sent for recycling before reinsertion, once

drippage passes through the final filter into a holding or process

tank (not a waste sump), the solution is no longer considered a

hazardous waste provided it is to be used for its originally intended

purpose (i.e., to treat wood). However, the quantity of waste that

was returned to the process must be "counted" at least once as

waste that was generated at the facility, and must be applied toward

determining generator status.

Question 2

Rainfall

• Is it acceptable to use meteorological data (e.g., rainfall per

year) to calculate the contribution of rainfall accumulating on

a drip pad toward a facility's generation of hazardous waste?

Precipitation hitting a Subpart W drip pad is considered hazardous

waste. Using meteorological data to calculate the contribution of

rainfall to wastewater is acceptable, provided the facility uses the
June 19, 1996

RCRA Waste Section 4 - 19

appropriate equipment (e.g., a rain gauge) and is able to

demonstrate to inspectors how the calculation was performed.

Question 3

Kiln Wastewater

• Does EPA consider wastewater condensate generated from

kiln drying treated wood hazardous waste under RCRA?

Yes, any drippage, condensate, or wastewater generated as a result

of kiln drying after the treatment of wood meets the definition of a

listed waste under RCRA (57 FR 61498; December 24, 1992).

The specific listing (i.e., F032, F034, or F035) will depend upon

the chemical formulation being used at the facility (the material could

also exhibit a characteristic of hazardous waste). It is important to

note, however, that steam or condensate which does not come into

contact with treated wood or preservative (i.e., condensate from

steam coils) does not meet the definition of a listed hazardous

waste.

Question 4

Liquid Separation of

Wastes

• A large quantity generator employing water-borne processes

is air drying residual wood preserving solution prior to the

disposal of wood chips. Is this considered "treatment" under

RCRA, and thus subject to permitting under 40 CFR Part

270?

Air drying is considered a form of treatment under RCRA.

According to Federal regulations, however, generators may treat

waste in accumulation units as long as they continue to comply with

all appropriate management standards described in 40 CFR

§262.34 (i.e., the chips are accumulated in tanks or containers that

meet the technical standards for such units in part 265 of the RCRA

regulations). As a result, no permit is required for air drying

activities unless the generator accumulates the waste on site for

longer than the allowable 90-day period provided to large quantity

generators (180 days for small quantity generators).

In addition, if the intent of the air drying process is liquid or

preservative recovery, this treatment is considered reclamation, and

is exempt from permitting under 40 CFR §261.6(c). Any materials

generated as a result of this drying (e.g., the wood chips that are

sent for disposal) are still considered a listed hazardous waste (via

the derived-from rule) and must be handled according to RCRA

regulations regardless of whether the drying was for treatment or for

reclamation. An exception is if the reclaimed liquids are to be used

again for wood treatment, in which case it is no longer be

considered a hazardous waste once reclamation is complete.
June 19, 1996

RCRA Waste Section 4 - 20

Process residuals can be placed on screens or racks over the sump

or drip pad to allow separation of liquid from solids. Liquid

separation of residuals and sludge must be performed in a closed,

labeled, mesh box in a well-ventilated area. Special precautions

should be taken against the release of process residual dust once

the material has dried.

Question 5

Switching

Formulations to

Nonhazardous

Generating

Preservatives

• Does a wood treater (large quantity generator) who switches

to a chemical that does not generate any RCRA hazardous

waste need to close the facility's drip pad before switching

processes?

Yes, the drip pad must be closed pursuant to applicable regulations

if the wood treater wishes to stop managing the drip pad as a

hazardous waste management unit (i.e., complying with Subpart W

standards). Closure of a drip pad is not required just because the

facility switches chemicals. However, if an owner or operator

changes chemicals without first performing clean closure according

to the RCRA drip pad closure requirements, the drip pad must

continue to be operated as a Subpart W drip pad and all

wastewater, preservative drippage, and process residuals

subsequently managed on the drip pad must continue to be treated

as hazardous waste.

To operate the drip pad as a non-hazardous waste management

unit (i.e., non-Subpart W drip pad), the large quantity generator

must follow the general closure standards set forth in 40 CFR

§265.111 and §265.114. This self-implementing performance

standard allows for the full decontamination of equipment,

structures, and soils. If decontamination cannot be accomplished,

the drip pad must satisfy full closure requirements under RCRA for

landfills. Finally, the decontamination process should be fully

documented. Generators must also follow the §262.34

accumulation time provisions to accommodate the safe disposal of

any hazardous wastes generated during closure activities.

Question 6

Discarded Treated

Wood

• The F032, F034, and F035 hazardous waste listings apply to

spent formulations from wood processing generated at plants

using pentachlorophenol, creosote, or chromated copper

arsenate. Are scrap pieces of wood treated with these

preservatives considered wastes when discarded?

Wood stickers, slabs, splinters, sawdust, or bark that are generated

as a result of the treatment process (i.e., particles that fall off of
June 19, 1996

RCRA Waste Section 4 - 21

wood into the cylinder, door pit, or drip pad during the treatment

process) are considered process residuals and thus listed hazardous

wastes under RCRA. These types of wastes are the direct result

of the treatment process and are considered part of the facility's

waste generation. Pieces that are cut off of finished products,

however, or that result from damage to the finished product after it

has been removed from the drip pad, are not considered listed

hazardous waste. However, waste scraps of wood may still exhibit

a characteristic of hazardous waste and thus be subject to

regulation under Subtitle C of RCRA.

Note: Discarded wood products that fail the toxicity

characteristic for D004-D017 are not hazardous wastes due to

an existing exclusion under RCRA for arsenical-treated wood

in §261.4(b)(9).

The post-consumer disposal of wood products that have been

treated with chemicals normally considered to be hazardous waste

(when generated at wood preserving facilities), are not considered

listed wastes under RCRA. For example, creosote treated railroad

ties are not listed hazardous wastes when disposed; however, they

may exhibit a characteristic of hazardous waste, in which case they

must be managed as hazardous waste.

Question 7

Retroactivity of

Waste Listings

• During remediation activities at a wood preserving facility,

soil is excavated and sent for disposal. Because of limited

records concerning past operations, the facility is having

difficulty determining the applicability of hazardous waste

listings. How is this type of waste usually characterized?

Wastes released prior to the development of the wood preserving

listings in 1990 that meet the listing description are not hazardous

wastes unless/until they are "actively managed." Active

management has been defined by EPA to comprise the physical

disturbance of accumulated hazardous waste (57 FR 37284;

August 18, 1992). The excavation of contaminated soils is one

example of an activity that EPA considers to be active management.

Once a waste is actively managed, hazardous waste listings

retroactively apply (i.e., waste that is actively managed will be

tested against the current listing description regardless of when it

was disposed). 

In determining whether the material in the soil meets a hazardous

waste listing, an owner/operator must gather enough evidence of
June 19, 1996

RCRA Waste Section 4 - 22

processes employed at the facility (both present and past) to reach

an accurate hazardous waste determination. EPA recognizes that

soil may contain preservative constituents due to rainwater wash-off

which does not meet the listing description (i.e., wash-off from a

storage yard does not meet a listing but still contains the same

constituents as a listed hazardous waste). Therefore, soils may

contain constituents and not meet the listing definition, but instead

may exhibit a characteristic of hazardous waste.

EPA has made a clear distinction between drippage and rainwater

wash-off:

“...The term ‘drippage’ refers to excess preservative that is kicked

back from the wood following treatment. It does not apply to

precipitation that drips from a stack of wood in the storage yard

when it falls from wood that has ceased to drip on the process area

drip pad before being moved to the storage yard (55 FR 50452;

December 6, 1990).”

Question 8

Underground Storage

Tanks

• A wood treatment plant stores copper sulfate in underground

storage tanks for use in a preservative process. Do the

requirements of 40 CFR Part 280 concerning underground

storage apply to these product tanks?

Yes, these types of tanks would be regulated under 40 CFR Part

280.

Question 9

De minimis Wastes

• What constitutes “de minimis” drippage for purposes of

Subpart W compliance?

The term “de minimis“ is not used by EPA in conjunction with

wood preserving wastes or the Subpart W drip pad standards. De

minimis drippage refers to an exempt volume of drippage, and no

volume of drippage of hazardous waste is exempt in the wood

preserving industry. Instead, EPA refers to drippage from

kickback in the storage yard as "infrequent and incidental

drippage." Kickback refers to wood preservative that is generated

from treated wood as the wood begins to return to normal pressure

after a pressure treating process.

Facilities must clean up kickback within 24 hours of the drippage

hitting the ground in accordance with a facility contingency plan. If

the release coincides with a holiday or weekend, the incidental

drippage must be cleaned up within 72 hours.
June 19, 1996

RCRA Waste Section 4 - 23

Additional information is available on the subjects discussed above: 

• For general information on RCRA, refer to EPA's RCRA Orientation Manual, 1990 Edition,

EPA/530-SW-90-036.

• For information on the specific regulations, consult the following sections of the Code of Federal

Regulations:

- Hazardous Waste Under RCRA — 40 CFR Part 261

- Definition of Solid Waste/Recycling Exemptions — 40 CFR 261.2

- Equipment Cleaning Procedures — 40 CFR 261.35

- Closed Loop Recycling — 40 CFR 261.4(a)(8)

- Direct Use/Reuse — 40 CFR 261.2

- Solid/Hazardous Waste Exclusions — 40 CFR 261.(4)(a)(8), (b)(9).

• For more information on hazardous waste counting, consult the May 11, 1995, Federal Register

(60 FR 25510).

• For more information on EPA's decision not to regulate wood surface protection wastes, please

consult the January 4, 1994, Federal Register (59 FR 458).

Question 10

Surface Protection

versus Wood

Treatment

• What is the difference between surface protection and wood

treatment?

If the purpose of the operation is to temporarily protect wood

against sap stains or other discoloration that may form on the

surface of the wood after cutting, it is considered by EPA to be

a wood surface protection process. Wastes from surface

protection operations are currently not regulated as listed hazardous

wastes by EPA. Wood preserving, on the other hand, involves the

application of chemicals to provide long-term protection against

structural problems in wood as a result of ground contact,

weathering, or insect damage.
Drip Pads Section 5 - 1

SECTION 5

DRIP PADS

Introduction Subpart W drip pads are hazardous waste management units that are

unique to the wood preserving industry. Drip pads are used to accumulate

and manage excess wood preserving formulations following the treatment

of virgin timber. In many cases, excess formulation dripping from the

treated wood is considered hazardous waste under RCRA.

EPA has issued specific regulations listing wood preserving process

wastes as hazardous. These hazardous wastes include wastewaters,

process residuals, preservative drippage, and spent formulations from

wood preserving operations using chlorophenolic formulations (F032),

creosote formulations (F034), and inorganic preservatives containing

arsenic or chromium (F035) (see Section 4 for a discussion of wastes

generated in the wood preserving industry).

Due to the nature of wood preserving wastes and the manner in which

they are generated (i.e., over a very large surface area), EPA discovered

that the regulations governing traditional RCRA hazardous waste

management units were not particularly useful. To accommodate this

uniqueness and to ensure proper and consistent waste management, in

1990 EPA developed specific standards for the design, installation,

operation, and closure of hazardous waste drip pads by recognizing drip

pads as a new type of hazardous waste management unit under RCRA.

This section of the Compliance Guide discusses these standards, which

are referred to as RCRA Subpart W standards.

Note: Owners/operators of wood preserving facilities can use tanks

or containers instead of drip pads to accumulate hazardous wastes

that are generated in the wood preserving industry, but no drippage

may occur outside the tank. Due to the unique manner in which

wood preserving wastes are generated (e.g., over a very large surface

area), use of a drip pad is often the most feasible way to contain and

accumulate hazardous waste that is generated from the treated

wood. Use of tank storage may be feasible at facilities using dip

tanks instead of pressure treatment. Also, tanks and containers can,

and often are, used elsewhere at wood preserving facilities to

accumulate other types of hazardous waste generated at other

locations on site.
June 19, 1996

Drip Pads Section 5 - 2

Regardless of the management practice used at a particular facility,

drippage that meets a listing description or exhibits a characteristic of

hazardous waste that is allowed to fall onto the ground or onto a nonregulated unit (e.g., a non-regulated drip pad) is considered illegal disposal

of a hazardous waste, and may be subject to enforcement action.

Incidental drippage in storage yards from charges of wood that remained

on drip pads until all drippage ceased is not considered a listed hazardous

waste. However, owners/ operators must maintain contingency plans for

cleanup of this type of drippage.

New vs. Existing

Drip Pads

Distinctions are made between new and existing drip pads. A drip pad is

considered existing if construction was completed prior to December 6,

1990. All other drip pads are considered new. A "new prime" drip pad

is one that contains both a leak detection and leak collection system as

specified in the regulations. Owners/operators of new drip pads must

comply with all of the standards discussed below. Existing drip pads may

need to be modified or "upgraded" to ensure adequate protection of

human health and the environment. EPA's regulation of existing drip pads

is also discussed below.

Drip Pad Design 

Standards

EPA has established specific drip pad design standards to ensure that drip

pads have sufficient structural strength to prevent failure of the drip pad

under the weight of wood and equipment. To accomplish this, all drip

pads must:

• Be constructed of non-earthen materials (this excludes wood and

non-structurally supported asphalt); drip pads are typically

constructed of concrete or steel

• Be sloped to ensure that drippage, wastewater, and other liquids

flow to a collection system and do not "puddle" on the drip pad

surface

• Have a curb or berm around the perimeter to prevent run-on and

run-off

• Be strong enough to stand up to daily operational activities, fork

lifts, traffic, and remain structurally sound and crack-free.

One of the main goals of the drip pad design standards is to prevent the

flow of waste from the drip pad to the surrounding environment. Subpart

W requires owners/operators to protect against the migration of hazardous

wastes and their constituents into the environment. An owner/operator

has two design options. 
June 19, 1996

Drip Pads Section 5 - 3

The first option is to apply a sealant or coating to the drip pad surface

to prevent hazardous wastes generated on the drip pad from seeping

through the drip pad and into the surrounding environment. Sealants

penetrate the surface of concrete drip pads and solidify to form an

impermeable surface. Coatings do not penetrate the surface of the drip

pad, but rather bond to the surface.

Because concrete, the most common construction material for drip pads,

is inherently porous, Subpart W dictates the following performance

standard for any sealant or coating:

• Once a sealant or coating is applied to an uncracked drip pad, the

drip pad must meet the hydraulic conductivity permeability

rating of 1 x 10-7 cm/sec (for more information see Appendix

B for contacts).

In general, sealants tend to hold up better than coatings under the stresses

of vehicle traffic, but tend to crack easily in conjunction with cracking

concrete underneath. Coatings do not bond as well to the concrete, but

tend to flex and protect the drip pad against micro-cracks.

Although the regulations were established under the assumption that

concrete would be used to construct the drip pad, other materials, such

as steel, are acceptable provided the hydraulic conductivity permeability

rating of 1 x 10-7 cm/sec is achieved. Because uncracked steel meets this

rating by itself, a sealer or coating is not necessary to satisfy RCRA

requirements.

The second option is to install a synthetic liner and leak detection

system/leak collection system below the drip pad to prevent leakage into

the adjacent subsurface soil, groundwater, or surface water. 

Owners/operators of both new and existing drip pads must employ at least

one of these methods to comply with the Subpart W standards (drip pads

that were constructed between December 6, 1990, and December 24,

1992 do not have to install a leak collection system with their leak

detection system). EPA does not recommend one option over the other,

but believes that installation of a liner and leak detection system will

require less maintenance and be less costly than repeated application of

surface coatings or sealants. Each of the design options for drip pads is

discussed in more detail below.

Exhibits 14 and 15 provide a side and front view of a typical drip pad.
June 19, 1996

Drip Pads Section 5 - 4

A B C D E F G H

A Curb or Berm

B Sealer/Coating

C Reinforced Concrete Pad: Design will be Determined by Wheel Load

D Drainfield of Graded Fill

E Perforated or Slotted Pipe Leading to Sump for Leak Detection System

F Synthetic Liner

G Base to Support Liner

H Existing Soil Substrate

SOIL SUBSURFACE

LEAK DETECTION SYSTEM

Water Stops

Structurally 

Reinforced 

Concrete

Impermeable 

Surface/ 

Coating

Curb

Exhibit 14

Side View of Typical Drip Pad

Exhibit 15

Front View of Typical Drip Pad
June 19, 1996

Drip Pads Section 5 - 5

Sealed Drip Pads Owners/operators electing to apply a coating or sealant to a drip pad must

cover the entire surface of the drip pad. The material used to seal the drip

pad must be compatible with the wood preservatives used by the facility

and must meet the hydraulic conductivity requirement of 1 x 10-7 cm/sec

specified in the regulations. Additional factors that should be considered

to ensure that the coating selected will achieve its standard for a particular

use: 

• Chemical resistivity

• Physical compatibility with service

• Adhesion capacity to substrate

• Temperature resistance

• Flexibility

• Scrubability

• Resistance to abrasion and impact

• Toxicity

• Drying and curing time

• Method and ease of application.

In addition to selecting a compatible sealant or coating, proper application

of the product is crucial in meeting the drip pad design standards. Proper

installation not only ensures that the hydraulic conductivity standard will be

achieved, but may also prolong the effectiveness of a particular coating,

reducing the necessity and frequency of reapplication. Coatings and

sealers should be chosen based on the service they will see on the drip

pad. For example, forklifts operating on a common area have been

known to tear coatings, while sealers have been found to better withstand

this type of pressure.

Drip Pad Liners Owners/operators who choose to install a liner and leak detection system

must also follow certain design criteria. Specifically, each liner must:

• Prevent leakage during the active life of the drip pad

• Resist absorption of waste

• Be constructed of material that is strong and thick enough to

prevent failure of the system

• Be placed on a foundation or base which can support the liner

• Cover all surfaces that could come in contact with waste or

leakage.

During construction or installation, each liner must be inspected for

structural defects. After construction, a registered, independent,

professional engineer must certify that the pad meets all requirements set
June 19, 1996

Drip Pads Section 5 - 6

forth in the Subpart W regulations. This certification must be kept in the

facility's operating log. 

Leak Detection

Systems

There are several specifications for the drip pad leak detection systems

that are used in conjunction with the synthetic liner. Leak detection

systems must be: 

• Located immediately above the liner

• Constructed of materials which can chemically resist waste and

physically resist pressure from above

• Designed to detect drip pad failure or the release of hazardous

waste or accumulated liquid at the earliest practicable time

• Designed and operated to function without clogging.

Liquid Collection

Systems

Owners/operators of Subpart W drip pads installed after December 24,

1992 choosing to comply with the synthetic liner option must also equip

the drip pads with a leak collection system to remove waste accumulating

on the liner. If this collection system involves the use of a tank or sump to

collect any excess liquids, the tank or sump will be subject to the

management standards applicable to hazardous waste tanks under RCRA

Subpart J. 

Tanks and sumps that are part of wastewater treatment units may be

exempt from RCRA regulation if they are otherwise subject to regulation

under the Clean Water Act (CWA). A discussion of Subpart J is

provided in Section 7.

Drip pad leak collection systems must be:

• Located immediately above the liner

• Designed, constructed, maintained, and operated so that leakage

can be removed from below the drip pad

• Designed and operated to convey, drain, and collect liquid in a way

that prevents run-off

• Emptied as necessary to ensure that the capacity of the system is

maintained.

Note: Leakage collection systems must be a collection device

separate from the sump or tank system used to collect liquid flowing

off of the drip pad.
June 19, 1996

Drip Pads Section 5 - 7

Run-on and Run-off 

Control

Drip pads that are not inside or otherwise covered must be equipped with

run-on and run-off control systems able to collect and control the

volume of rainwater from a 24-hour, 25-year storm. This system must be

designed and operated to stop the flow of water both onto and off of the

drip pad. In addition, any collection units associated with such systems

must be emptied as soon as possible after storms to maintain the system's

design capacity.

Note:Regardless of whether a pad is covered, a curb or berm around

the perimeter of the drip pad is required.

Drip Pad Operation There are several requirements concerning the operation of drip pads.

• The entire surface of the drip pad must be cleaned to allow for

weekly inspection. The frequency and method of cleaning must be

documented in the operating log (residues from drip pad cleaning

are hazardous waste and must be managed accordingly).

• Drip pads must be maintained free of cracks that would otherwise

adversely affect hydraulic conductivity, corrosion, or deterioration

that could result in leakage.

• The drip pad must be operated in a way that minimizes the tracking

of hazardous waste off of the drip pad by personnel and equipment.

This may be accomplished by controlling employee access and

having a dedicated forklift on the drip pad.

• After treatment, wood must remain on the drip pad until all

drippage has ceased. The operating log must document that each

charge has stopped dripping before it is removed from the pad.

• Collection systems and holding units for run-on and run-off control

must be emptied as soon as possible after storms.

Temporary

Accumulation of

Hazardous Waste on

Drip Pads

As discussed in Section 3 of this Guide, generators may use drip pads as

hazardous waste accumulation units to temporarily store hazardous waste.

A generator who accumulates hazardous waste on a drip pad for 90 days

or less is not required to obtain a RCRA storage permit as long as: 

• The drip pad satisfies technical standards set out in the regulations

• The facility has written procedures to ensure that wastes are

removed from the pad and collection system at least every 90 days

• Records are kept documenting that these procedures are followed,

the date and time of removal, and the quantity removed. 
June 19, 1996

Drip Pads Section 5 - 8

This 90-day limit applies to both large quantity and small quantity

generators. While small quantity generators may normally accumulate

hazardous waste in accumulation units for up to 180 days, this is not the

case for small quantity generators accumulating waste on Subpart W drip

pads. Owners/operators of wood preserving facilities who generate

between 100-1000 kg of hazardous waste per calendar month and who

accumulate the waste on drip pads are not eligible for the reduced

standards normally provided for small quantity generators. Instead, these

generators must comply with all the management requirements for large

quantity generators accumulating hazardous waste on drip pads.

Note: Hazardous waste that is generated elsewhere at the wood

preserving facility and accumulated in tanks or containers (i.e., not

accumulated on drip pads) will remain subject to small quantity

generator standards. Only waste that is accumulated on drip pads

must adhere to the large quantity generator standards.

Conditionally exempt small quantity generators are not subject to the

90-day accumulation limit, nor are they required to accumulate their

hazardous wastes in any particular type of unit, including drip pads.

Allowing hazardous waste to fall onto the ground is viewed as illegal

disposal, and may result in an enforcement action if inspectors determine

that such disposal threatens human health or the environment. As such, it

is prudent for all wood preserving facilities, even if conditionally exempt,

to ensure that they are operating their drip pads in an environmentally safe

and responsible manner.

Assessment of Drip

Pad Integrity

Many wood preserving facilities were already in existence when the drip

pad standards were first issued. In fact, many facilities had been in

operation for a number of years prior to development of the standards,

and had been using drip pads to collect drippage from treated wood. In

light of the potential cost to the existing facilities to upgrade every drip

pad, EPA developed a certification program that allows owners/operators

to assess and certify the integrity of existing drip pads until all repairs or

upgrades have been made. By upgrade, EPA means the installation

of a leak detection and leak collection system, not the application

of a sealant or coating. Although owners/operators may still select

which compliance option to implement, only a drip pad that has a leak

detection/leak collection system will be considered "upgraded" for

purposes of these standards.
June 19, 1996

Drip Pads Section 5 - 9

Existing Drip Pads Until a drip pad has been upgraded to include a liner and leak

detection/leak collection system, owners/operators must evaluate each

existing drip pad to determine the extent to which it meets all Subpart W

design and operating requirements. A written assessment of the drip pad,

attesting to the results of the evaluation, must be certified by an

independent, qualified, registered professional engineer and kept on file at

the facility. This assessment must be renewed, updated, and recertified

annually until all upgrades have been made.

Although owners/operators may choose to apply a sealant and not install

a liner in order to comply with applicable requirements, only those who

install a liner and leak detection/leak collection system are relieved of the

responsibility to conduct an annual assessment of the drip pad's integrity.

Even if a facility installs a new drip pad and chooses to apply a coating or

sealant instead of a liner system, the Subpart W standards still require an

annual drip pad assessment. Thus, when determining which upgrade

option is most suitable to a particular facility, owners/operators should

compare the cost of performing annual assessments to the cost of installing

a liner system. 

Note: Existing drip pads constructed between December 6, 1990,

and December 24, 1992, that are being upgraded only require the

installation of a leak detection system, and not a leak collection

system as well. Any drip pad constructed after December 24, 1992,

must include both a leak detection and leak collection system to be

considered "upgraded" for purposes of Subpart W. EPA does

recommend installation of both to ensure protection of human health

and the environment. See Exhibit 16 for design and certification

requirements.

Although there is no specified date by which all facilities operating Subpart

W drip pads must demonstrate that existing drip pads meet upgrade

requirements, EPA feels that most facilities will choose to upgrade their

drip pads with a liner and leak detection/leak collection system in light of

long-term cost savings to the facility. Once a facility has upgraded its drip

pads to comply with the leak detection/leak collection system and has

obtained proper certification, no further annual assessment is required.

New Drip Pads New drip pads must be assessed upon initial construction. During

construction or installation, all liners and cover systems must be evaluated

for uniformity, damage, and imperfections (e.g., holes, cracks, spots) that

could potentially affect the drip pad's ability to protect against preservative

leakage to the surrounding environment. Once construction is complete,
June 19, 1996

Drip Pads Section 5 - 10

the drip pad must be inspected by an independent, qualified, registered

professional engineer to ensure that it meets all applicable design

requirements. All certifications must be kept as part of the facility's

operating log. Unlike existing drip pads that have not yet been fully

upgraded, there are no annual recertification requirements for new drip

pads that have been constructed with a liner and leak detection/leak

collection system. Exhibit 16 contains a summary of the drip pad

construction and certification requirements.

Note: EPA strongly encourages the use of both a liner system and

application of a coating or sealant to the drip pad to ensure safe

hazardous waste management. This will help to prevent present and

future threats to human health and the environment posed by

accidents, leaks, or general wear and tear.
June 19, 1996

Drip Pads Section 5 - 11

Existing Drip Pad 

(Constructed* Before

December 6, 1990)

Apply Impermeable 

Sealant or Coating

Upgrade Drip Pad to Install 

Liner and Leak Detection/ 

Collecting System

New Drip Pad

(Constructed* Between

December 6, 1990) 

and 

December 24, 1992)

Sealant or Coating that 

meets 1x10-7cm/sec

Install Liner and Leak

Detection System

New Drip Pad

(Constructed* After

December 24, 1992)

Sealant or Coating that

meets 1x10-7cm/sec

Upgrade Drip Pad to Install 

Liner and Leak Detection/ 

Collecting System

OR

OR

OR

Annual Professional

Engineer (PE) Certification

One-Time PE Certification of

Drip Pad Liner

Annual PE Certification of

Drip Pad

One-Time PE Certification of

Drip Pad and Liner

Annual PE Certification of

Drip Pad

One-Time PE Certification

of Drip Pad and Liner

* “Under Construction” includes those drip pads for which an owner/operator signed or entered into a 

binding financial agreement for construction prior to this date.

Type of Drip Pad Construction Options Type of Certification Required

Exhibit 16

Drip Pad Construction and Certification Requirements

Inspections Drip pads must be inspected weekly and after storm events. The

inspection must include checks for deterioration of the run-on and run-off

control systems, the presence of leakage, proper functioning of the leak

detection system, and deterioration of the drip pad surface. Records of

drip pad inspections should be maintained at the facility for at least three

years from the date of inspection. Exhibit 17 contains information

concerning a facility's obligations with respect to drip pad inspection and

maintenance.
June 19, 1996

Drip Pads Section 5 - 12

Does the 

Drip Pad 

Have any Cracks?

No

N o

Obtain 

Recertification

1. Obtain Recertification 

2. Renotify EPA Regional 

Administrator and 

Provide Copy of 

Recertification

Check Pad 

Frequently

(Recommended)

Does Crack 

Effect the 

Hydraulic 

Conductivity 

of the Pad?

Did the Crack(s)

Lead 

To a Release 

To the 

Environment?

Note Cleaning 

in Log

No

No

1. Take Cracked Portion of 

the Pad Out of Service 

2. Notify the EPA Regional 

Administrator or 

Delegated State Director 

Within 24 Hours 

3. Record Release in 

Operating Log

Take Cracked Portion of Drip

Pad Out of Service and 

Repair

1. Clean Up Waste 

2. Repair Crack 

Yes

Yes

Yes

Exhibit 17

Responding to Drip Pad Cracks 

Operating Log A drip pad owner/operator must comply with several recordkeeping

requirements. Facilities are required to keep an operating log to document

many of their activities with respect to drip pad maintenance and the

management of hazardous waste. It is advisable to keep all information

related to hazardous waste management activities in the operating log.

The following operations and activities must be documented in the facility's

operating log:

• Leakage/drippage — date, time, and quantity of leakage

collected and removed from leakage collection system, drip pad,

and sump

• Drip Pad Cleaning — date and time of each drip pad and all

cleaning procedures

• Drip Pad Operation — documentation that all treated wood is

held on the pad until drippage has ceased
June 19, 1996

Drip Pads Section 5 - 13

• Inspections — documentation of all inspections conducted in

accordance with the requirements of Subpart W. To inspect a drip

pad, owners/ operators must look for deterioration, malfunctions or

improper operation of run-on and run-off control systems, proper

operation of leak detection systems and leakage from these

systems, and deterioration or cracking of the drip pad's surface.

• Waste Handling — documentation of facility waste handling

practices, including preservative formulations used in the past,

drippage management practices, and treated wood storage and

handling practices. The log must describe the operation that will be

followed to ensure that all wastes are removed from the drip pad

and collection system at least once every 90 days.

Releases of 

Hazardous Waste 

from Drip Pads

There are several steps a facility must take in the event of a release of

hazardous waste from a drip pad. Upon discovery of a release,

owners/operators must:

• Discontinue operations on the affected portion of the drip pad

• Record the leak in the facility operating log, noting the date and time

• Determine what repairs are required, remove leakage from below

the pad, and establish a schedule for cleanup and repair

• Notify the EPA Regional Administrator or delegated State director

within 24 hours of discovery, and provide a written description of

the planned cleanup and repair within 10 days

• Promptly perform repairs

• Following completion of repairs, notify the EPA Regional

Administrator in writing that the cleanup and repairs were

completed in accordance with the previously submitted plan. This

notification must be certified by a registered, professional engineer.

Note:It is not EPA's intent to require owners/operators to notify the

EPA Regional Administrator for every repair made to a Subpart W

drip pad. The owner/operator must notify the EPA Regional

Administrator or State director only when there has been an actual

release of hazardous waste from the drip pad. Cracks and other

conditions that have the potential to lead to a release in the future

need not be reported. Owners/operators must still make all

appropriate repairs in a timely fashion and note the repairs in the

facility log.
June 19, 1996

Drip Pads Section 5 - 14

Contingency Plans Each facility must develop a contingency plan that describes the steps an

owner/operator will take in response to a leak of hazardous waste from

drip pads. Large quantity generators are required by regulation to

develop such plans and amend them whenever necessary. A copy of the

contingency plan must be maintained at the facility and submitted to all

local police departments, fire departments, hospitals, and State and local

emergency response teams. Contingency plans must contain the following

information:

• General information about the facility

• The name, address, and phone number of the emergency

coordinator and an alternate emergency coordinator

• Emergency procedures to be followed in the event of a spill, fire, or

explosion

• The evacuation plan and a list of all emergency equipment at the

facility.

Small quantity generators are also required to have contingency plans.

These plans may be less detailed than those required for large quantity

generators. However, because they are held to the same standards as

large quantity generators when accumulating hazardous waste on drip

pads, small quantity generators are required to develop full contingency

plans identical to those required of large quantity generators.

Conditionally exempt small quantity generators are not required to

maintain contingency plans under RCRA, but are encouraged to do so.

Note:This facility contingency plan is different from the storage yard

clean-up plan that is also required under the drip pad standards.

Closure of Drip Pads To ensure that drip pads are properly managed when operations have

ceased, all drip pads must be "closed" in a way that prevents future

migration of contaminants into the environment. Closure of a drip pad

involves removal or decontamination of all waste residue, contaminated

soils, and equipment. If it is impossible or impractical to remove all

contaminated soil, the unit must be treated and closed in a manner similar

to a hazardous waste landfill. Generators accumulating hazardous waste

on drip pads are also subject to certain closure requirements. For a more

detailed discussion concerning generator closure requirements, see

Section 3 of this Guide.

Upon closure, owners/operators may also choose to remove and dispose

of old drip pads at a facility. These drip pads will most likely be

considered listed hazardous waste by virtues of being debris which is
June 19, 1996

Drip Pads Section 5 - 15

contaminated with a listed hazardous waste (e.g., F032, F034, F035). In

such cases, it is possible to grind and separate the drip pad into those

portions which do contain listed hazardous waste, and those that remain

uncontaminated because they never had any contact with a listed waste at

all. By separating the two waste streams, owners/operators can reduce

waste management costs by sending only those portions of the drip pad

that are contaminated with listed hazardous waste to a hazardous waste

landfill.

Frequently Asked

Questions

The following are frequently asked questions concerning regulatory

scenarios encountered at wood preserving facilities. Please consult the

appropriate implementing agency for final regulatory determination

regarding site-specific situations.

Question 1

Closure Timeframe

• Once a large quantity generator begins closure activities on

a Subpart W drip pad, is there a specific timeframe during

which closure activities must be completed?

There is no specified time frame during which generators

accumulating hazardous waste on drip pads must complete closure

activities; however, other RCRA regulations may prevent

owners/operators from accumulating hazardous waste on-site

longer than 90 days without obtaining a RCRA permit. Section

262.34 allows large quantity generators to accumulate hazardous

waste on-site for up to 90 days. A large quantity generator in the

process of closing a drip pad will, in fact, lose its generator status

if closure activities necessitate storing hazardous waste on site for

longer than 90 days. If the 90-day limit is exceeded, the facility will

enter interim status, and all applicable closure timelines for interim

status facilities will apply. 

Although no timeframes exist for generator closure activities on the

Federal level, owners/operators should consult the appropriate

State hazardous waste agency to learn of possible State regulations.

Many States allow no more than 180 days to complete closure

activities.

Question 2

Drip Pad Cleaning

• Subpart W requires owners/operators to clean the hazardous

waste drip pads to allow for weekly inspections. Is shoveling

the drip pad considered an appropriate method for meeting

this requirement?
June 19, 1996

Drip Pads Section 5 - 16

EPA intentionally developed the drip pad cleaning requirements to

be performance-based. Thus, any method that allows

owners/operators to effectively conduct the required weekly

inspection of the drip pad is appropriate. When performing

cleaning activities, owners/operators must take special precautions

to avoid damage to the impermeable surface of the drip pad (if

owners/operators have chosen to comply with that design option).

Question 3

Curbs on Covered

Drip Pads

• If a drip pad is covered by a roof, is a curb required?

In order to meet the Subpart W drip pad design criteria, a drip pad

must have a curb to prevent precipitation run-off and run-on.

However, if a drip pad is inside or under a cover (i.e., a roof) and

the surrounding landscape is graded so that run-on cannot occur,

the drip pad curb need not be very high to prevent run-on and

 run-off of rain occurring during a 24-hour, 25-year storm. The

requirement in §265.443(f) is designed for those facilities that do

not have enclosed drip pads.

Structures built over drip pads should meet the following

specifications:

1. The structure must cover the drip pad entirely and have

eaves that extend beyond the curb of the drip pad to prevent

most wind-blown rain from hitting the drip pad.

Owners/operators may also install walls outside the curb to

serve the same purpose.

2. Owners/operators should install rain diverters, gutters, or

similar devices that prevent water from running off the roof

and onto the drip pad.

Question 4

Certification of

Operating Practices

• Is the professional engineer (PE) certification required to

address operating conditions at the facility in addition to

assessing and certifying the drip pad's integrity?

No, the purpose of the PE certification is to assess the physical and

structural aspects of the drip pad, not the facility's operating

practices.

Question 5

Upgrading Drip Pads

• Are owners/operators of existing drip pads required to

upgrade their pads to meet all of the design criteria of

Subpart W? If so, when must these upgrades be complete?
June 19, 1996

Drip Pads Section 5 - 17

No, the final drip pad standards do not contain a final deadline by

which owners/operators must upgrade their drip pads to install

liners and leak detection systems. Instead, owners/operators of

existing pads that have not been upgraded must continue to annually

certify the integrity of their existing drip pad until such upgrades are

completed. A written plan for upgrading is only required if the

treater plans to upgrade the drip pad to include a liner. Such plans

must be submitted at least two years prior to upgrading.

Question 6

Collection System

and Drip Pad 

Clean-out

• After cleaning the drip pad and the collection system (sumps)

every 90 days, as required for large and small quantity

generators, how long can the hazardous waste remain on

site?

If the hazardous waste is placed in satellite accumulation areas, the

waste can remain there until the drum is full. Once the drum is full,

it must be dated and moved to the hazardous waste storage area.

The 90 or 180 day accumulation clock starts once the hazardous

waste has been sealed into a drum or placed in a tank.
June 19, 1996

Drip Pads Section 5 - 18

Additional information is available on the subjects discussed above: 

• For general information on RCRA, refer to EPA's RCRA

Orientation Manual, 1990 Edition, EPA/530-SW-90-036.

• For information on the specific regulations, consult the following

sections of the Code of Federal Regulations:

- New vs. Existing Drip Pad — 40 CFR 265.440

- Assessment of Existing Drip Pad Integrity — 40 CFR

265.441

- New Drip Pad Design Standards — 40 CFR 264.573 and

265.443

- Sealed Drip Pads — 40 CFR 265.442

- Drip Pad Liners — 40 CFR 264.573 and 265.443

- Leak Detection/Collection Systems — 40 CFR 264.573

and 265.443

- Uncovered Drip Pads — 40 CFR 265.440

- Drip Pad Operations — 40 CFR 265.443

- Temporary Accumulation of Hazardous Waste on Drip

Pads — 40 CFR 262.34 

- Releases of Hazardous Waste from Drip Pads — 40 CFR

265.443, 265.445

- Recordkeeping and Reporting Requirements — 40 CFR

265.444

- Contingency Plans — 40 CFR 265.440

- Closure of Drip Pads — 40 CFR 265.111, 265.114,

265.445.
Storage Yards Section 6 - 1

SECTION 6

STORAGE YARDS

Introduction Most wood preserving facilities maintain storage yards to hold treated

charges of wood until they are sent off-site for sale. Because of the

high cost of controlling wastes in storage yards (e.g., building storage

sheds and paving storage yards), EPA has imposed minimal RCRA

regulation on the management of storage yards at wood preserving

facilities. Because of enhanced waste minimization efforts throughout

the wood p5reserving industry and the drip pad operating standards of

Subpart W, little waste, if any, is generated in these areas.

The drip pad regulations require that all treated wood (from both

pressure and non-pressure processes) be held on drip pads until

drippage has ceased. Incidental and infrequent drippage in the storage

yard from a charge that stopped dripping before it was removed from

the drip pad is not considered illegal disposal if it is cleaned up within

24 hours (or 72 hours if the drippage occurs on a holiday or weekend)

in accordance with the facility's contingency plan. Drippage that is

cleaned up must be handled as hazardous waste.

The contingency plan must be developed and maintained on file at the

facility. The contingency plan must describe how the facility will:

• Clean up any drippage within 72 hours of occurrence (not

detection)

• Document the cleanup of such drippage, and retain records of

the cleanup for a period of three years

• Manage any contaminated media (e.g., soil, water) as F-listed

hazardous waste or characteristic hazardous waste.

EPA expects an adequate storage yard contingency plan to include

frequent storage yard inspections, to ensure that incidental drippage and

soils are cleaned up within 24 hours (72 hours if over a holiday or

weekend).

EPA encourages owners/operators of facilities to develop grid locator

systems in their storage yards to facilitate the tracking of cleanup

activities. In addition, EPA also recommends constructing covered

storage yards to reduce the potential of run-off contamination.
June 19, 1996

Storage Yards Section 6 - 2

Additional information is available on the subjects discussed above: 

• For information on the specific regulations, consult the following section of the Code of Federal

Regulations:

- Storage yard contingency plans — 40 CFR §265.440(c).

• For more information on the management of drippage in storage yard, consult the regulatory

interpretive correspondence dated May 31, 1991, written from Lowrance to Hazardous Waste

Management Division Directors. This memorandum is also a part of the RCRA Permit Policy

Compendium, #9489.1991(02).

Stormwater Run-off in

Storage Yards

Generally, stormwater runoff in storage yards is not considered a listed

waste. EPA has clarified that the hazardous waste listings for wood

preserving chemicals do not apply to precipitation run-off from treated

wood in storage yards without drip pads, where the owner or operator

has allowed the treated wood to sit on the drip pad until all drippage

has ceased. This is consistent with EPA's general position that the

derived-from rule does not apply to precipitation run-off (see 40 CFR

261.3(c)(2) and 45 FR 33096; May 19, 1990). Stormwater that falls

onto the drip pad, however, and that is collected and disposed, will be

considered a listed waste and subject to RCRA regulation.

As discussed above, owners/operators must keep treated wood on

drip pads until all drippage has ceased. In order for precipitation runoff in storage yards not to be considered a listed hazardous waste, an

owner/operator must show through its records that the facility complies

with this requirement. In the case of incidental drippage in storage

yards, owners/operators must maintain a spill contingency plan for such

occurrences. If the facility does not have documentation that it is in

compliance with Subpart W, EPA can assert that the stormwater

transported a listed hazardous waste and that the resulting sludge also

carries the listing. 

EPA encourages the construction of stormwater run-off mitigation

systems and the appropriate handling of sediments generated as a result

of such management. In addition, any of these wastes may exhibit a

characteristic of hazardous waste, even though they may not meet a

listing description.
Tanks and Sumps Section 7 - 1

SECTION 7

TANKS AND SUMPS

Introduction Tanks are used by wood preserving facilities in a number of ways. Some

tanks are used to mix and store preservative solution, while others are

used to store and treat hazardous waste generated as a result of wood

preserving operations. Tanks that are used to mix and store preservative

solution which does not contain RCRA hazardous waste are not covered

by the regulations described below. If, however, tanks are used to

accumulate, store, or treat waste from the wood preserving process, such

as hazardous waste drippage from Subpart W drip pads, the tanks are

governed by RCRA Subpart J requirements. 

Both large and small quantity generators accumulating hazardous waste in

tanks are required to comply with the requirements in Subpart J. Large

quantity generators must follow the interim status tank standards in 40

CFR Part 265, and small quantity generators are governed by special tank

standards, also in Part 265, Subpart J.

Note: A small number of wood preserving facilities perform nonpressurized wood treatment using large tanks of preservative

formulation in which charges of wood are submerged. If the facility

has not been equipped with a Subpart W drip pad, the charge must

remain over the tank until all drippage has ceased.

Sumps are man-made reservoirs built into the ground that are designed

to capture waste from troughs or trenches. Sumps meet the definition

of tanks under RCRA, and are subject to regulation under Subpart J.

Both tanks and sumps are often used to capture waste from drip pads.

Tanks and sumps that are part of wastewater treatment units may be

exempt from RCRA regulation if they are otherwise subject to regulation

under the Clean Water Act (CWA).

This section of the Compliance Guide will discuss the following RCRA

requirements that apply to tanks:

• Tank Assessment

• Secondary Containment and Leak Detection

• Ancillary Equipment

• Operating and Maintenance Requirements

• Inspections
June 19, 1996

Tanks and Sumps Section 7 - 2

• Response to Releases

• Closure

• Underground Storage Tanks (USTs).

New vs. Existing

Tanks

Different regulatory requirements apply depending on whether tanks are

classified as "existing" or "new" under RCRA. The "new" versus "existing"

distinction dictates when secondary containment systems must be installed.

Tanks which held hazardous waste before July 14, 1986 (the effective

date of applicable EPA regulations), are classified as "existing," while

tanks that began holding hazardous waste after that date are considered

"new." New tanks also include reinstalled and replacement tanks or

components.

All tanks must be assessed to evaluate structural integrity and compatibility

with the wastes that the tank will hold. The assessment must address

design standards, corrosion protection, testing, and the age of the tank.

Assessment of 

Existing Tanks

Most existing tanks do not have to meet the technical standards for new

tanks until the tank system is 15 years old. To ensure the tank's structural

integrity until then, existing tanks without secondary containment systems

(secondary containment systems are discussed in detail below) must be

assessed for leakage and overall fitness. The assessment must show that

the tank is not leaking and is otherwise fit for use. This assessment was

to have occurred by January 12, 1988.

An assessment of an existing tank must verify that the tank was designed

and maintained to contain the particular wastes stored or treated without

failing, collapsing, or rupturing. The written assessment must be certified

by a registered professional engineer and placed in the facility's operating

log.

Assessment of New

Tanks

New tanks must satisfy the following requirements:

• The system must have adequate foundations, structural support, and

corrosion protection to prevent collapse, rupture, or failure.

• All seams and connections must be adequately sealed.

• Facilities must prepare a written design assessment, which must be

certified by a registered professional engineer and kept in the

operating log.
June 19, 1996

Tanks and Sumps Section 7 - 3

New tanks must be inspected prior to use by a registered professional

engineer to ensure no damage to the tank occurred during tank installation

or that necessary repairs were properly performed. All new tanks and

ancillary equipment must be tested for tightness, and any leaks must be

remedied before the tank may be used. The assessment must ensure the

following:

• Design and method of operation will protect underground

components from damage caused by vehicle traffic.

• Tank foundations will support the load of a full tank.

• Tank is anchored to prevent floating or dislodgment.

• Tank can withstand the effects of frost.

• Backfill, used for underground tank systems, made up of

noncorrosive, porous, and homogeneous materials, has been placed

to ensure proper support.

• Ancillary equipment has been supported and protected against

physical damage.

Corrosion Protection New tanks and tank system components made in whole or in part of metal

must have adequate corrosion protection if the system will be in contact

with soil or water. One or more of the following corrosion protection

methods is required:

• Use of materials that are corrosion-resistant.

• Corrosion-resistant coating in combination with cathodic protection

(cathodic protection prevents corrosion by reversing naturally

occurring electrical current in tanks, for example through the use of

sacrificial anodes).

• Electrical isolation devices.

Regardless of the protection method used, installation of the corrosion

protection system must be supervised by an independent corrosion expert.

Leak Detection and

Secondary

Containment

Secondary containment and leak detection systems allow detection of

leaks from the primary or inner tank and provide an emergency, shortterm secondary barrier to contain releases and prevent them from entering

into the environment. These systems also provide protection from spills

caused by operational errors, such as overfilling. Large sumps under

retort areas should not be considered secondary containment if they

routinely hold hazardous wastes generated from the retort.
June 19, 1996

Tanks and Sumps Section 7 - 4

All new hazardous waste tank systems not otherwise exempted from

regulation must have secondary containment and leak detection.

Secondary containment and leak detection for existing tanks is to be

phased in over time, based on the age of the tank and its hazardous waste

contents. For example, existing tanks of known and documented age

must have detection and containment within two years after January 12,

1987, or when the tank system has reached 15 years of age.

A secondary containment system must satisfy the following requirements:

• Designed, installed, and operated so that no waste is released to

surrounding soil, groundwater, or surface water

• Constructed of material or liner that is compatible with the waste

being stored or treated in the tank

• Capable of containing accumulated waste until it is removed

(accumulations must be removed within 24 hours)

• Structurally strong enough to prevent failure

• Foundation must be capable of resisting failure due to normal

movement of the surrounding soils.

Leak Detection

Systems

As part of the secondary containment system, hazardous waste tanks must

be equipped with a leak detection system capable of detecting failure

either in the primary or secondary containment structures. The presence

of accumulated materials in the secondary containment system must be

detected within 24 hours or at the "earliest practicable time." Thermal

conductivity sensors, electrical resistivity sensors, and vapor detectors are

common leak detection devices. Daily visual inspections may be used

where tanks and tank components are accessible.

Secondary

Containment Devices

Secondary containment systems prevent waste leaking from the tank from

migrating to the soil, groundwater, or surface water. The containment

device must be capable of detecting and collecting releases and must be:

• Constructed of or lined with materials compatible with the waste to

be contained

• Strong enough to prevent failure from pressure, contact with the

waste, climate, and the stress of daily operations

• Placed on a foundation capable of supporting the system

• Equipped with a leak detection system

• Sloped or otherwise designed to drain or remove liquids resulting

from spills, leaks, or rain.
June 19, 1996

Tanks and Sumps Section 7 - 5

Hazardous waste tank regulations require the use of one of the following

four secondary containment systems:

• Anexternal liner designed to work in connection with a barrier —

the liner must be free of cracks and should completely surround the

unit with an impermeable material. The liner can be made of many

different types of materials, including synthetic membranes,

concrete, clay, cement, or asphalt, and must be large enough to

contain 100 percent of the capacity of the largest hazardous waste

tank within its boundary. The liner must be designed to prevent

run-on and run-off.

• A vault, which is an underground area designed to contain releases

not visible to the operator — if the vault is constructed of concrete,

it must have a waterproof exterior and must be lined inside with a

leak proof sealant. The vault must be large enough to contain 100

percent of the capacity of the largest hazardous waste tank within

its boundary and must be equipped with protection against the

formation and ignition of vapor within the vault.

• A double-walled tank ("tank within a tank") — this option is

considered to be the most protective. A double-walled tank must

be designed and constructed so that any release from the inner tank

is completely contained by the outer tank. Such tanks must be

equipped with built-in, continuous leak detection.

• An alternative equivalent device, subject to the approval of the

EPA Regional Administrator.

Exemption from

Secondary

Containment

Requirement

Some tanks may automatically qualify for an exemption from secondary

containment and leak detection requirements. One exemption applies to

tanks, including sumps, that serve as part of a secondary containment

system. This exemption does not apply to drip pad sumps as these sumps

serve as primary, not secondary, containment systems.

Secondary

Containment for

Ancillary Equipment

All ancillary equipment must have full secondary containment. Ancillary

equipment includes devices such as piping, fittings, flanges, valves, and

pumps, that are used to distribute, meter, or control the flow of hazardous

waste from its point of generation to a storage or treatment tank.

Examples of secondary containment for ancillary equipment include use of

a trench, jacketing, or double-walled piping. If inspected daily, the

following equipment is exempt from this requirement:
June 19, 1996

Tanks and Sumps Section 7 - 6

• Aboveground piping

• Welded flanges, joints, and connections

• Seal-less or magnetic coupling pumps

• Aboveground pressurized piping systems with automatic shut-off

devices.

Operating and

Maintenance

Requirements

Hazardous waste tanks and secondary containment systems must be

operated so that releases will be minimized or eliminated. Spills or

overflows from the tank or secondary containment system must be

prevented by:

• Using spill prevention controls, such as check valves

• Using overfill prevention controls such as alarms and automatic feed

cutoffs

• Maintaining sufficient distance between the top of the tank and the

surface of the waste in the tank (freeboard).

Inspections To verify that hazardous waste tanks, components, and secondary

containment systems are operated and maintained in satisfactory condition,

routine inspections are required. Records of all tank inspections should

be kept in the operating log.

The following tank system components must be inspected at least once a

day:

• Overfill/spill control equipment to ensure it is in good working order

• Aboveground portions of the tank system to detect corrosion or

release of waste

• Data gathered from monitoring and leak detection equipment

• Construction materials and the area immediately surrounding the

accessible portion of the tank system, including secondary

containment structures, to detect corrosion or waste release.

The cathodic protection system must be inspected within six months of

installation and annually thereafter. All sources of impressed current (a

specific type of corrosion protection using direct current from an external

source) must be inspected and/or tested at least every other month.

Response to

Releases

A tank system or secondary containment system that has leaked must be

taken out of operation immediately. The flow of waste into the tank must

be stopped, and the system must be inspected to determine the cause of
June 19, 1996

Tanks and Sumps Section 7 - 7

the release. All visible contamination must be removed and properly

disposed. Any waste remaining in the tank must be removed within 24

hours.

Unless the release is exempt (leaks of less than one pound that are

immediately contained are exempt from Federal reporting obligations), the

facility must immediately notify the EPA Regional Administrator or the

National Response Center (NRC) and submit a follow-up written report

to the EPA Regional Administrator within 30 days. 

The tank must then be repaired, equipped with secondary containment (if

not already equipped), or closed. If the leaking component is

aboveground and can be inspected visually, secondary containment does

not need to be provided after repair. 

If any of the repairs are major, they must be certified by a registered

professional engineer; this certification must be submitted to the EPA

Regional Administrator within seven days after returning the system to

service. Except for the notification and reporting requirements, the above

procedures apply even if a release has been contained by a secondary

containment system. 

Closure When a tank containing hazardous waste at a wood preserving facility is

no longer used, or abandoned, owners/operators must complete proper

closure activities to complete their regulatoryresponsibilities. Whenever

possible, a storage or treatment tank system must be "clean closed" by

removing or decontaminating all waste residues, contaminated containment

system components, and contaminated soils, structures and equipment.

If clean closure is not possible, the facility may opt to leave the

contamination in place. If this occurs, the facility must develop a plan for

taking care of the remaining waste for a number of years after closure,

similar to that developed for a landfill.

Underground 

Storage Tanks

EPA has developed a separate regulatory program for underground

storage tanks (USTs). Tanks regulated under this program contain what

are called "regulated substances" which include petroleum products and

hazardous substances as defined under CERCLA. The primary distinction

between the regulations described above and USTs is the content of the

tanks. Specifically, underground storage tanks are those underground

tanks storing "regulated substances." The definition of regulated substance

specifically excludes any RCRA hazardous wastes. Thus, any tank

holding a RCRA hazardous waste will not be subject to the Part 280

underground storage tank regulations.
June 19, 1996

Tanks and Sumps Section 7 - 8

Additional information is available on the subjects discussed above: 

• For general information on RCRA, refer to EPA's RCRA Orientation Manual, 1990 Edition,

EPA/530-SW-90-036.

• For information on the specific regulations, consult the following sections of the Code of Federal

Regulations:

- Exclusion from Tank Regulations — 40 CFR §§ 264.1(c)(10); 270.1(c)(2)(v)

- New vs. Existing Tanks — 40 CFR §260.10

- Assessment of Existing Tanks — 40 CFR §265.191

- Design of New Tanks — 40 CFR §265.192

- Secondary Containment and Leak Detection — 40 CFR §265.193

- Variance from Secondary Containment Requirements — 40 CFR §265.193(g)

- Secondary Containment for Ancillary Equipment — 40 CFR §265.193(f)

- Operating and Maintenance Requirements — 40 CFR §265.194

- Inspections — 40 CFR §265.195

- Response to Releases — 40 CFR §265.196

- Closure — 40 CFR §265.197

- Underground Storage Tanks — 40 CFR Part 280.
Drip Pads Section 8 - 1

SECTION 8

ADDITIONAL FEDERAL STATUTORY REQUIREMENTS

Clean Water Act In 1972, Congress passed the Federal Water Pollution Control Act,

commonly referred to as the Clean Water Act (CWA). The goal of the

CWA is to restore and maintain the chemical, physical, and biological

integrity of the nation's surface waters by prohibiting the discharge of

pollutants to surface waters in toxic amounts.

The CWA regulates both direct and indirect discharges. Direct discharges

or "point source" discharges are from sources such as pipes and sewers.

Indirect discharges through publicly-owned treatment works (POTWs)

are regulated by the industrial waste pretreatment program.

NPDES Program The National Pollutant Discharge Elimination System (NPDES),

promulgated pursuant to CWA §402, is the national program for issuing,

monitoring, and enforcing permits for direct discharges of pollutants to the

navigable waters of the United States. NPDES permits, issued by either

EPA or an authorized State, contain industry-specific, technology-based

and/or water quality-based effluent limits, and establish pollutant

monitoring and reporting requirements. A facility that intends to discharge

into the nation's waters must first obtain an NPDES permit. A permit

applicant must provide quantitative analytical data identifying the types of

pollutants present in the facility's effluent discharge. The permit will then

set forth the conditions and effluent limits under which a facility may

discharge.

The NPDES permit application, whether for a new discharge or for an

existing discharge, requires extensive information about the facility and the

nature of the discharge from the facility. EPA application forms include

Form 1 (general information), Form 2 (detailed information on existing

sources), Form 2D (detailed information on new sources and new

discharges), Form 2E (for facilities that discharge only non-process

wastewater), and Form 2F (for stormwater discharges). State

application forms must, at a minimum, require the information required by

EPA's forms. 

One of the primary purposes of the NPDES permit is to establish effluent

limitations. The CWA mandates a two-part approach to establishing

effluent limitations. First, all dischargers are required to meet specific

established treatment levels. The effluent limitations for the wood
June 19, 1996

Drip Pads Section 8 - 2

preserving industry are found in 40 CFR Part 429. Second, more

stringent requirements must be met where necessary to achieve water

quality goals for the particular body of water into which the facility

discharges. 

Stormwater

Discharges

In 1987, Congress amended the CWA and created a program for the

comprehensive control of stormwater discharges. Pursuant to that

delegated authority, EPA established a stormwater program which

requires facilities to obtain a permit for stormwater discharges associated

with industrial activity, including discharges to a municipal storm sewer.

All wood treating plants, regardless of size, must obtain an NPDES permit

for stormwater discharges. The permit is a legally enforceable agreement

between the regulatory agency (either EPA or the State) and the industrial

facility that governs the quality of stormwater effluent released into

receiving waters, such as creeks, streams, ponds, and rivers.

EPA published permit application requirements for stormwater discharges

associated with specific industrial activities in the Federal Register on

November 16, 1990 (55 FR 47990). The regulations outline three permit

application options for stormwater discharges associated with industrial

activity:

1 - Submit an individual application. An individual permit application

requires detailed quantitative information based on sampling of stormwater

discharges collected during storm events.

2 - Participate in a group application. Group applications allow similar

dischargers to apply as a group for a permit. This type of permit reduces

the cost of compliance for group members and the administrative costs for

regulators. Additional information on group applications is provided in the

September 29, 1995, Federal Register (60 FR 50804).

3 - File a Notice of Intent (NOI) to be covered under a general multisector stormwater permit. Under the multi-sector permit, stormwater

dischargers have to develop site-specific pollution prevention plans based

on industry-specific best management practices specified in the permit.

NPDES stormwater permits are issued by the EPA Regional office or by

States authorized by EPA to administer the program. Contact your EPA

Regional office to determine who is administering the program in your

facility's jurisdiction.
June 19, 1996

Drip Pads Section 8 - 3

Pretreatment

Program

Industrial discharges that do not discharge directly into waters of the U.S.,

but instead discharge into a public sanitary sewer system are regulated

under the CWA pretreatment program (CWA §307(b)). The national

pretreatment program controls the indirect discharge of pollutants to

POTWs by industrial users. Facilities regulated under §307(b) must

pretreat their wastewater before discharging. The goal of the pretreatment

program is to protect municipal wastewater treatment plants from damage

that may occur when hazardous, toxic, or other wastes are discharged into

a sewer system. Discharges to a POTW are regulated primarily by the

POTW itself, rather than by the State or EPA. EPA has developed

technology-based pretreatment standards for categories of industrial users

of POTWs; different standards apply to existing and new sources within

each category. 

EPA's Office of Water, at (202) 260-5700, will direct callers with

questions about the CWA to the appropriate EPA office. EPA also

maintains a bibliographic database of Office of Water publications

which can be accessed through the Ground Water and Drinking

Water resource center, at (202) 260-7786.

Federal Insecticide,

Fungicide, and

Rodenticide Act

(FIFRA)

The Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA),

regulates chemicals with pesticidal properties that are sold in commerce

as poisons. Many of the chemicals used by the wood preserving industry

are regulated under FIFRA. 

Wood preserving formulations must be registered with EPA by the

producer. To register a chemical, an application package that includes

product chemical composition and health risk data must be submitted to

EPA.

Under FIFRA, products are classified as either a restricted-use or

general-use pesticide. This classification must appear on product labels.

Wood preserving formulations containing creosote, pentachlorophenol,

and inorganic salts such as chromated copper arsenate are classified as

restricted-use pesticides. The application of such formulations is therefore

limited to licensed pesticide applicators or an individual under the direct

supervision of a licensed pesticide applicator. Wood preserving facilities

using these formulations must have at least one employee who is licensed

to apply restricted-use pesticides. The standards for licensing are

established by the Federal government or by State governments with

Federal approval. (A list of State contacts for licensing is provided in

Appendix B).
June 19, 1996

Drip Pads Section 8 - 4

In addition to the licensing requirements, wood preserving facilities using

arsenic are required to either conduct air monitoring on personnel working

in areas where arsenic exposure might occur or require operators to wear

respirators. This air monitoring and associated recordkeeping must be

done in accordance with EPA's Permissible Exposure Limit (PEL)

Monitoring Program. The analytical results from the PEL Monitoring

Program must be submitted annually to PEL Monitoring, U.S. EPA.

Wood Products Contact 

PEL Monitoring (2223A) 

Manufacturing Branch 

U.S. Environmental Protection Agency

401 M Street, SW

Washington, D.C. 20460

In order to educate consumers on the safe and proper handling of wood

treated with creosote, pentachlorophenol, and inorganic arsenicals, a

voluntary Consumer Awareness Program was established jointly by

EPA and the wood preserving industry. Through the program, a

Consumer Information Sheet (CIS) containing information about treated

wood is distributed to end-users at the time of sale or delivery. The CIS

contains language agreed upon by EPA and the wood treatment industry.

The primary responsibility for ensuring that the CIS is distributed to the

consuming public resides with the wood treaters. They are responsible for

distributing CISs and signs and placards to their retailers, wholesalers, and

distributors, and attaching a CIS to each bundle or batch of pressure

treated wood as well as to each invoice.

EPA's National Pesticides Telecommunications Network, at (800)

858-PEST, answers questions and distributes guidance regarding the

registration of pesticides, labeling, the PEL Modeling Program, and

the Consumer Awareness Program. The Network operates weekdays

from 6:30 a.m. to 4:30 p.m., PST, excluding Federal holidays.

Clean Air Act The Clean Air Act (CAA) is the principal Federal statute governing air

pollution and is administered by EPA. EPA may grant States the authority

to administer certain provisions of the CAA following approval of State

Implementation Plans (SIPs).

Currently, the CAA does not impact wood preserving processes directly,

however several portions of the Act may affect facility operations. For

instance, boilers burning sawdust for fuel may be regulated for particulates

emitted to the atmosphere. Some States regulate kilns using natural gas
June 19, 1996

Drip Pads Section 8 - 5

for fuel, and require a permit for their use. If you use a fuel oil or diesel

back-up, your State may require emissions data on sulfur dioxide.

Title I of the CAA established New Source Performance Standards

(NSPSs), which are national emission standards for new stationary

sources falling within particular industrial categories. The NSPS

regulations in 40 CFR 60.110b - 60.117b might apply to an oil borne

wood processing facility if the facility uses a process tank that has a design

capacity of over 40 cubic meters and was built after July 23, 1984.

Pursuant to the CAA, EPA has established National Emission Standards

for Hazardous Air Pollutants (NESHAPs). NESHAPs are national

standards oriented toward controlling particular hazardous air pollutants

(HAPs). Wood treating plants are not currently regulated under these

rules. Although arsenic, copper, chromium, and pentacholorphenol are

listed as HAPs, no standards have been established for them. 

Under the CAA Title V, each industrial source of air emissions that is

defined as a Òmajor sourceÓ must submit a permit application. One

purpose of the permit is to include all air emissions requirements that apply

to a given facility in a single document. A Òmajor sourceÓ is defined as

a stationary source that:

• Emits or has the potential to emit 100 tons per year of any pollutant

listed under §302 of the CAA.

• Emits or has the potential to emit certain criteria pollutants (volatile

organic compounds, nitrogen oxides, sulfur oxides, carbon

monoxide, lead, and particulates) in non-attainment areas

designated under Title I.

• Emits or has the potential to emit 10 tons per year of any HAP

(listed in CAA §112(b)), or 25 tons per year of any combination of

HAPs, or any source subject to NSPSs or NESHAPs.

Most wood treating facilities will be considered minor sources of air

pollution; however, documentation to establish this classification may be

requested by EPA or the State. One method of calculating emissions

potential is to review equipment specifications provided by the designer

or supplier. Other calculation methods include evaluating the quantities of

chemicals purchased and processed per year.

In the 1990 Clean Air Act Amendments, Congress added subsection (r)

to CAA section 112 for the prevention of chemical accidents. The goals
June 19, 1996

Drip Pads Section 8 - 6

of the chemical accident prevention provisions are to focus on chemicals

that pose significant hazard to the community should an accident occur, to

prevent their accidental release, and to minimize the consequences of such

release. Regulations for the §112(r) Risk Management Program are

currently being established by EPA. To date, EPA has established the list

of chemicals and thresholds for on-site storage and use, but not the

requirements for risk management plans. These rules may be applicable

to wood preserving facilities. EPA's EPCRA Hotline will be able to

provide specific information about this reporting requirement when it is

published in the Federal Register.

EPA's Control Technology Center, at (919) 541-0800, provides

general assistance and information on CAA standards. The

Stratospheric Ozone Information Hotline, at (800) 296-1996,

provides general information about regulations promulgated under

Title VI of the CAA, and EPA's EPCRA Hotline, at (800) 535-0202,

answers questions about accidental release prevention under CAA

§112(r). In addition, the Technology Transfer Network Bulletin

Board System (modem access (919) 541-5742) includes recent CAA

rules, EPA guidance documents, and updates of EPA activities.

Comprehensive

Environmental

Response,

Compensation, And

Liability Act

The Comprehensive Environmental Response, Compensation, and

Liability Act (CERCLA) of 1980, commonly known as Superfund,

authorizes EPA to respond to releases, or threatened releases, of

hazardous substances that may endanger public health, welfare, or the

environment. CERCLA also enables EPA to force parties responsible for

environmental contamination to clean it up or to reimburse the Superfund

for response costs incurred by EPA. The Superfund Amendments and

Reauthorization Act (SARA) of 1986 revised various sections of

CERCLA, extended the taxing authority for the Superfund, and created

a free-standing law, SARA Title III, also known as the Emergency

Planning and Community Right-to-Know Act (EPCRA). A discussion of

the EPCRA regulations follows the discussion of CERCLA.

The CERCLA hazardous substance release reporting regulations found in

40 CFR Part 302 direct persons in charge of facilities to report to the

National Response Center (NRC) any release of a hazardous substance

which within a 24-hour period equals or exceeds a designated reportable

quantity (RQ). The NRC, located at U.S. Coast Guard Headquarters

((800) 424-8802), is a national communications center continuously

staffed to handle activities related to spills and releases. 
June 19, 1996

Drip Pads Section 8 - 7

Hazardous substances and RQs are defined and listed in 40 CFR §302.4.

Arsenic, chromium, cresote, and pentachlorophenol are a few of the

hazardous substances listed in 40 CFR §302.4 often found at wood

preserving facilities and for which reporting may be required. The RQs for

these substances are:

• Arsenic - 1 lb.

• Chromium - 5,000 lbs.

• Creosote - 1 lb.

• Pentachlorophenol-10 lbs.

The Superfund Hotline can provide RQs for other specific hazardous

substances and assist in determining which releases are reportable. A

report of a release may trigger a response by EPA, or by one or more

Federal or State emergency response authorities.

EPA implements hazardous substance responses according to procedures

outlined in the National Oil and Hazardous Substances Pollution

Contingency Plan (NCP) (40 CFR Part 300). The NCP includes

provisions for permanent cleanups, known as remedial actions, and other

cleanups referred to as "removals." EPA generally takes remedial actions

only at sites on the National Priorities List (NPL), which currently includes

approximately 1300 sites. As of May 1996, approximately 45 sites were

on the NPL because of contamination stemming from wood preserving

operations.

EPA's RCRA/Superfund/UST Hotline, at (800) 424-9346, answers

questions and references guidance pertaining to the Superfund

program. The Hotline operates weekdays from 9:00 a.m. to 6:00

p.m., EST, excluding Federal holidays.

Emergency Planning

And Community

Right-To-Know Act

The Superfund Amendments and Reauthorization Act (SARA) of 1986

created the Emergency Planning and Community Right-to-Know Act

(EPCRA), also known as SARA Title III. This law was designed to

improve community access to information about potential chemical

hazards and to facilitate the development of chemical emergency response

plans by State and local governments. EPCRA required the establishment

of State Emergency Response Commissions (SERCs), responsible for

coordinating certain emergency response activities and for appointing

Local Emergency Planning Committees (LEPCs).
June 19, 1996

Drip Pads Section 8 - 8

EPCRA regulations, at 40 CFR Parts 350-372, establish four types of

reporting obligations for facilities which store or manage specified

chemicals:

• EPCRA §302 - Emergency Planning requires facilities to notify

their SERC and LEPC of the presence of any extremely hazardous

substance (EHS) in excess of the substance's threshold planning

quantity (TPQ) (the list of EHSs and TPQs is in 40 CFR Part 355,

Appendices A and B). EPCRA §302 also directs facilities to

appoint an emergency response coordinator. It is unlikely that this

section of EPCRA is applicable to the wood preserving industry

because the types of chemicals generally stored do not meet the

regulatory definition of an extremely hazardous substance.

• EPCRA §304 - Emergency Release Notification requires

facilities to notify the SERC and LEPC in the event of a release

exceeding the reportable quantity of either a CERCLA hazardous

substance or an EPCRA extremely hazardous substance which may

affect persons beyond the facility's boundaries.

• EPCRA §§311/312 - Hazardous Chemical Inventory

Reporting requires facilities at which a hazardous chemical, as

defined by the Occupational Safety and Health Act, is present in an

amount exceeding a specified threshold to submit material safety

data sheets (MSDSs) and hazardous chemical inventory forms (also

known as Tier I and II forms) to the SERC, LEPC, and local fire

department by March 1 of every year. This information helps the

local government respond to a spill or release of the chemical.

Many of the chemicals used by wood treaters are defined as

hazardous chemicals.

• EPCRA §313 - Toxic Chemical Release Inventory requires

manufacturing facilities included in SIC codes 20 through 39, which

have ten or more full-time employees, and which manufacture,

process, or use specified chemicals in amounts greater than

threshold quantities, to submit an annual toxic chemical release

report by July 1 of every year. The SIC code for lumber and wood

products is 24. This report, commonly known as the Form R,

covers releases and transfers of toxic chemicals to various facilities

and environmental media, and allows EPA to compile the national

Toxic Release Inventory (TRI) database.

All information submitted pursuant to EPCRA regulations is publicly

available, unless protected by a trade secret claim. 
June 19, 1996

Drip Pads Section 8 - 9

EPA's EPCRA Hotline, at (800) 535-0202, answers questions and

distributes guidance regarding EPCRA regulations. A guidance

document, ÒTitle III Section 313 Release Reporting Guidance,

Estimating Chemical Releases from Wood Preserving Operations,Ó

is available from the Hotline. The EPCRA Hotline operates

weekdays from 9:00 a.m. to 6:00 p.m., EST, excluding Federal

holidays.

Safe Drinking Water

Act 

The Safe Drinking Water Act (SDWA) mandates that EPA establish

regulations to protect human health from contaminants present in drinking

water. The law authorizes EPA to develop national drinking water

standards and to create a joint Federal-State system to ensure compliance

with these standards. The SDWA also directs EPA to protect

underground sources of drinking water through the control of underground

injection of liquid wastes.

The SDWA may be of concern to the wood preservers if dry wells are

used. If water contaminated with wood preservative is allowed to drain

into a dry well, it could lead to contamination of underground sources of

drinking water. Under the SDWA, a permit program for the safe disposal

of wastes through controlled underground injection has been established.

The Underground Injection Control (UIC) program (40 CFR Parts 144-

148) regulates five classes of injection wells and may be applicable to

wood treaters. UIC permits include design, operation, inspection, and

monitoring requirements. Wells used to inject hazardous wastes must also

comply with RCRA corrective action standards to be granted a RCRA

permit, and must meet applicable RCRA land disposal restriction

standards.

EPA's Safe Drinking Water Hotline, at (800) 426-4791, answers

questions and distributes guidance pertaining to SDWA standards.

The Hotline operates from 9:00 a.m. through 5:30 p.m., EST,

excluding Federal holidays.

DOT's Hazardous

Materials

Transportation Act

(HMTA)

The Department of Transportation (DOT) regulates all aspects of the

shipping and receiving of hazardous materials when those activities are

performed in commerce. ÒIn commerceÓ includes the shipping of

hazardous materials typically found at wood treatment sites, such as

chromium, pentachlorophenol, arsenic, and creosote, to an industrial

facility for use in industrial processes. 
June 19, 1996

Drip Pads Section 8 - 10

Hazardous materials are those materials that DOT has determined may

harm human health and the environment during shipping. Hazardous

materials include specific hazardous chemicals, such as arsenic acid, but

also include general hazardous categories, or classes. The DOT

Hazardous Materials Table (49 CFR Part 172.101) includes a list of all

hazardous materials, as well as requirements for proper shipment of listed

items. The Hazardous Materials Table also provides information on

proper containers and labels, as well as vehicle requirements.

DOT requires that proper shipping papers accompany all shipments of

hazardous waste or hazardous materials. Shipping papers indicate what

is being shipped, the quantity being shipped, and the particular hazards of

the material. When shipping wood preserving chemicals, an Annotated

Bill of Lading may be used that includes all required DOT shipping

information. For shipping hazardous waste, a RCRA hazardous waste

manifest must be used.

DOT's Hazardous Materials Information Line, at (800) 467-4922,

provides general assistance and information on HMTA regulations.

The Information Line operates weekdays from 8:00 a.m. to 5:30 p.m.,

EST, excluding Federal holidays.

Pollution Prevention

Act

Congress enacted the Pollution Prevention Act in 1990 to promote

pollution prevention in existing regulatory programs, including EPCRA,

RCRA, CWA, and CAA. The first step in pollution prevention is the

development and implementation of a pollution prevention plan. Wood

preserving facilities are impacted by pollution prevention regulations

related to the generation of hazardous and non-hazardous waste in the

treating process, and through other activities and stormwater control

measures.

For assistance in developing a facility pollution prevention plan,

contact the regulatory Hotlines for the EPCRA, RCRA, CWA, and

CAA programs.

Toxic Substances

Control Act

The Toxic Substances Control Act (TSCA) grants EPA the authority to

create a regulatory framework to collect data on chemicals in order to

evaluate, assess, mitigate, and control risks which may be posed by their

manufacture, processing, and use. Wood treating plants may be affected

by a TSCA reporting requirement promulgated pursuant to section 8(c)

of TSCA and found at 40 CFR §717. These regulations enable

employees, consumers, the general public, or environmental advocacy
June 19, 1996

Drip Pads Section 8 - 11

groups to allege that the chemicals used by a plant caused an adverse

effect to their health or the environment that had not been previously

identified. If such an allegation is made, it should be documented on

company letterhead and placed in the company's TSCA 8(c) file for future

reference.

EPA's TSCA Assistance Information Service, at (202) 554-1404,

answers questions and distributes guidance pertaining to TSCA

standards. The Service operates from 8:30 a.m. through 4:30 p.m.,

EST, excluding Federal holidays.
June 19, 1996

Drip Pads Section 8 - 12

Additional information is available on the subjects discussed above. The following is a list of Code of

Federal Regulation citations applicable to the wood preserving industry.

• For regulatory information on Clean Water Act, consult the following sections of the Code of Federal

Regulations:

- National Pollutant Discharge Elimination System - 40 CFR Parts 122 and 125

- Effluent Guidelines and Standards for the Timber Products Processing Point Source Category -

40 CFR Part 429

• For regulatory information on FIFRA, consult the following sections of the Code of Federal

Regulations: 

- Worker Protection Standards - 40 CFR Part 170

- Certification of Pesticide Applicators - 40 CFR Part 171

- For information about the PEL monitoring program, see Federal Register Vol.49, no.136, July 13,

1984, p28666-28689.

• For regulatory information on the Clean Air Act, consult the following sections of the Code of Federal

Regulations: 

- New Source Performance Standards - 40 CFR §60.110b - 60.117b

- National Emission Standards for Hazardous Air Pollutants - 40 CFR Part 61

- Risk Management Programs - 40 CFR Part 68

- National Emission Standards for Hazardous Air Pollutants for Source Categories - 40 CFR Part

63

• For regulatory information on the Superfund program, consult the following sections of the Code of

Federal Regulations: 

- National Contingency Plan - 40 CFR Part 300

- Hazardous Substance Release Reporting - 40 CFR Part 302

• For regulatory information on EPCRA, consult the following sections of the Code of Federal

Regulations: 

- Emergency Planning - 40 CFR Part 355

- Release Reporting - 40 CFR §355.40

- Hazardous Chemical Inventory Reporting - 40 CFR Part 370

- Toxic Chemical Release Reporting - 40 CFR Part 372

• For regulatory information on the Safe Drinking Water Act, consult the following sections of the Code

of Federal Regulations: 

- Underground Control Program - 40 CFR Parts 144-148

• For regulatory information on DOT's Hazardous Materials Transportation Act, consult the following

sections of the Code of Federal Regulations: 

- Hazardous Materials Table - 49 CFR §172.101

• For regulatory information on TSCA, consult the following sections of the Code of Federal

Regulations: 

- Records and Reports of Chemical Health Effects - 40 CFR Part 717