Document ID: EPA-HQ-OAR-2021-0133-0010
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2022-03-07T05:00Z

﻿                  UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
           SECTOR POLICIES AND PROGRAMS DIVISION
           OFFICE OF AIR QUALITY PLANNING AND STANDARDS
           OFFICE OF AIR AND RADIATION

DATE:January 19, 2021 

SUBJECT:Documentation of Phone Conferences with Railway Tie Association

FROM:John Bradfield (EPA/OAR/OAQPS/SPPD/NRG)

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TO:EPA-HQ-OAR-2021-0133
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The purpose of this memorandum is to discuss the phone conference between John Bradfield of the U.S. Environmental Protection Agency (EPA) with Ashley Goodin of Railway Tie Association (RTA) on December 23, 2020 regarding wood preservatives used in the railway tie industry. This information will be used in the technology review for the National Emission Standards for Hazardous Air Pollutants for Wood Preserving Area Sources (Subpart QQQQQQ).  RTA provided the following information regarding current wood preservation treatments for railway ties. 
 
Wood Preservation Treatments
85% of ties are treated with creosote, most of them are dual treated with a dual treatment of borates, followed by creosote.
15% of ties are treated with copper naphthenate. Most of the ties used for bridges are copper napthenate and are pine.
Dual treatment extends tie life 15-20%.  Dual treatment is required for class 1 railroads except in cold weather/low termite areas (e.g. Canada). Many of the ties in cold weather areas are dual treated, regardless, because of their superiority against fungal attack, too.
92% of railway ties are wood treated in North America.
Effective use of creosote, with dosages being adjusted to reflect actual preservative effectiveness requirements, is a recent development.
Concrete/Wood Considerations
8% of railway ties are concrete in North America, though there is a higher percentage usage in Europe.
Wood and concrete ties cannot be alternated in the same section. However, ties can alternate on longer sections of track (e.g., a mile) between wood and concrete.
More ballast is required beneath concrete tracks.
The elastic properties of wood are better than concrete and they can withstand greater loads. With the trend towards heavier, longer trains, wood has an advantage.
For areas of track where there are potential derailment issues, wood is preferred due to its elasticity and greater flexibility.