CASE STUDY 

Explosion and Fire in 

West Carrollton, Ohio 

(Four Workers Injured, 

 Community Damage) 

2009-10-I-OH 

JULY 21, 2010

Photo Courtesy of Ohio State Fire Marshal

Veolia Technical Solutions, LLC 

West Carrollton, Ohio

May 4, 2009

Key Issues: 

• Unsafe Building Siting

• Atmospheric Relief Systems

• Plant Emergency Procedures

 

This case study examines an

explosion and fire at the Veolia ES 

Technical Solutions, LLC, facility in 

West Carrollton, Ohio, that severely

injured two workers and slightly 

injured two others. Eight structures at 

the plant sustained damage, as did 

approximately 20 residences and 

businesses offsite. 

INSIDE ... 

Introduction 

Process Discussion 

The Incident 

Consequences 

Emergency Response

Findings 

Analysis

Recommendations 
Veolia ES Technical Solutions, L.L.C. Case Study JULY 2010

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1.0 Introduction

At about 12:07 a.m. on May 4, 2009, highly

flammable vapor, released from a waste 

recycling process, ignited and violently 

exploded, severely injuring two employees and 

slightly injuring two others at Veolia ES 

Technical Solutions, LLC. Multiple explosions 

afterward significantly damaged every structure 

on the site. Residences and businesses in the 

surrounding community also sustained

considerable damage. The fire was declared 

under control by 10:38 a.m. that day. 

1.1 Veolia Corporation

The West Carrollton facility opened in 1979 as 

Solvent Resource Recovery and, after several

name changes, became Chemical Waste 

Management (CWM) Resource Recovery in 

1988. In 1999, Vivendi, a French company 

purchased the facility as part of a larger 

acquisition and transferred the assets to Onyx 

Environmental Services, L.L.C. (OES). 

On July 1, 2006 the site was renamed Veolia ES 

Technical Solutions, L.L.C. (VESTS)—a 

subsidiary of Veolia Environmental Services 

North America Corp. (VESNA). VESNA is a

publicly traded subsidiary of Veolia 

Environnement, which employs more than 

300,000 worldwide. 

1.2 Company Background1

The Veolia facility is approximately 7 miles 

southwest of Dayton, Ohio, and is located on 

Infirmary Road, 0.7 miles north of the 

intersection with Farmersville West Carrollton 

Road. The surrounding land is used for 

residential, industrial, and farming purposes.

 

The company provided hazardous waste services 

for industrial and municipal customers. The 

Veolia site, an estimated 20 acres, employed 

 

1

 Part of the facility is being rebuilt and some is still 

in operation, but for the sake of consistency, and to 

avoid confusion, past tense will be used throughout 

this document.

about 72 workers on the day of the incident. Six 

employees were at work on the night of the 

incident. Veolia is a member of the 

Environmental Technology Council (ETC), a 

national trade association of commercial 

environmental firms that recycle, treat, and 

dispose of industrial and hazardous waste. 

The CSB issued two recommendations to ETC 

as the result of an investigation of a fire in 2006 

at a hazardous waste facility located in Apex, 

North Carolina. ETC has not acted upon 

either of these recommendations to date.

Governed by U.S. Environmental Protection 

Agency (EPA) regulations authorized by the 

Resource Conservation and Recovery Act 

(RCRA), Veolia is a state-permitted treatment, 

storage, and disposal facility (TSDF). The site 

was subject to inspections by the Ohio EPA 

twice a year, and customers audited between 20 

and 40 times a year. The site provided the 

following services to waste generators:

• Fuel Blending: Received flammable and 

combustible waste streams (liquids, solids, 

and sludge), consolidated them into 

marketable waste-derived fuels, and shipped

them for burning in energy-recovering 

cement kilns. Bulk and containerized wastes 

arrived in liquid, solid, or sludge/slurry 

form.

• Solvent Recovery: Distilled and reclaimed

liquid waste solvents that arrived in loads. 

The facility had three distillation units that

produced usable solvent from this waste 

material. 

• Waste Consolidation: Consolidated like 

materials into larger containers, usually 55-

gallon drums. If possible, the consolidated 

material was blended or recovered onsite; 

otherwise, it was transported to other 

locations. 

• Waste Material Transfer: Received, 

stored, packaged, and transferred waste 

which did not require treatment, fuel

blending, or disposal. 
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Figure 1. Aerial view of the Veolia facility (Montgomery County, OH GIS Photo)

1.3 Facility Description

Employees occupied a number of structures at 

the site depending on the time of day. The 

lab/operations building and the administration 

building were the two with the most employees. 

The lab/operations building was a multi-use 

structure that served as the primary workstation 

for lab technicians, lab managers, production 

clerks, plant operators, and supervisors. The 

building also housed a control room, 

break/dining area, laboratory, and locker rooms. 

Eight offices were contained within the building. 

Three boilers were located in the northwest 

section of the lab/operations building. The north 

wall of this building was less than 30 feet from 

the operating units. 

The administration building, located about 500 

feet south of the operating plant, provided office 

and meeting space for plant management, 

technical, accounting, environmental health and 

safety, and other personnel. 

The remaining structures were the decant, drum 

storage, non-hazardous waste processing, and 

maintenance buildings. The processing area 

consisted of two tank farms and three solvent 

recovery units.
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2.0 Process Discussion 

2.1 Solvent Recovery Process 

Description

Veolia processed hazardous and non-hazardous 

waste products at the West Carrollton site. The 

facility received waste solvent in bulk tanker

trucks and drums. The waste streams received 

for recovery were dirty or spent solvents from 

industrial generators. Typical solvent blends 

consisted of aliphatic hydrocarbons, chlorinated 

hydrocarbons, esters, ketones, and alcohols. The 

residue, or “still bottoms,” that remained after 

onsite distillation consisted of plasticizers, 

resins, pigments, and residual solvents. 

Tanker trucks were unloaded directly into bulk 

storage tanks (dirty tanks) at the trailer 

containment areas. Drums were unloaded into 

receiving areas for temporary staging. Waste 

was then decanted into bulk storage tanks or 

repackaged for shipment offsite. Veolia either 

returned clean solvent to the generator for reuse 

or sold the product to other industrial users after 

purifying it by distillation. Veolia also 

transported non-distillables to an offsite 

permitted hazardous waste facility for 

combustion either in a supplemental fuels 

program or in a hazardous waste incinerator for 

safe destruction. 

Figure 2. Plot plan of Units 1, 3, and 4; clean and dirty tanks; and the lab/operations building (not to scale)

Veolia recovered and recycled waste solvents to 

95 to 99 percent concentration. Twenty-three 

carbon steel “dirty” tanks and 16 stainless steel 

“clean” tanks ranging in capacity from 8,000 to 

20,000 gallons abutted Units 1, 3, and 4 to the 

east and west, respectively (Figure 2). Incoming 

solvents were unloaded into tanks in the dirty 

tank farm. Dirty tanks acted as feed tanks for the 

solvent recovery process, and clean tanks 

received and stored recovered product. 

A three-inch vapor-piping manifold, called the 

“vapor balance system,” equalized the gas 
Veolia ES Technical Solutions, L.L.C. Case Study JULY 2010

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pressure above the liquid contents when loading 

and unloading the tanks. The dirty tank farm and 

the clean tank farm had independent vapor 

balance pipe systems, though the dirty tank 

vapor balance system was connected to the 

molecular sieve unit and the drum disposal unit

at the decant building.

Units 1, 3, and 4, the three distillation units, and 

one molecular sieve processed the dirty solvents. 

The molecular sieve removed water from certain 

solvent streams and was connected to the dirty 

tank vapor balance system. Processed solvents 

were then stored in stainless steel tanks in the 

clean tank farm.

Units 1 and 3 operated continuously while Unit 

4 used a batch process. Unit 1 was composed of 

a thin film evaporator and condenser.2 Unit 3 

consisted of a wiped film evaporator, 

fractionating distillation column, and 

condenser.3 Unit 4 used a 12,000-gallon batch 

still, reboiler, fractionating distillation column, 

and condenser.4

Three natural gas-fired tube boilers produced 

120-psig steam for both process use and building 

heat. A Therminol 55® hot oil unit provided 

process heat for evaporators in Units 1 and 3. 

The facility used nitrogen to regenerate the 

molecular sieve, blanket the hot oil unit, and 

purge the drum disposal unit. 

One operator was responsible 

for operating all units under the direction of a 

shift supervisor and a reclaim supervisor. The 

units operated 24 hours a day, seven days a 

week as needed to meet production demands.

 

2

 Thin film evaporators heat the raw material on the 

internal surface of a heated tube until the lower 

boiling component starts to evaporate. 

3

 Wiped film evaporators increase evaporation or 

separation of heat-sensitive liquids. Feed flows 

down the inside of a cylindrical vessel wall, while 

rotating wiper blades spread the material across the 

wall and maintains a uniform film of the material. 

4

 OSHA Process Safety Management (PSM) covered 

process. 

3.0 The Incident

The incident occurred at about 12:07 a.m. on 

May 4, 2009, when highly flammable vapor 

released from a waste recycling processing area

in the dirty tank farm ignited and violently 

exploded, severely injuring two Veolia

employees. One employee suffered first-degree 

burns and a second broke his pelvis. Multiple 

explosions ensued, significantly damaging a

majority of the facility, surrounding businesses 

and residences.

The two most severely injured were both in the 

lab/operations building at the time of the 

incident. One worker was in the control room, 

located about 25 feet from the operating unit, 

when the escaping vapor ignited. He reported 

being enveloped “[in a] fireball that...went 

through the building [and that] seemed to stop as 

fast as it started.” Shortly after the first series of 

explosions, this worker was seen exiting the area 

to a pre-arranged assembly point at the main 

gate. West Carrollton Fire Department (WCFD) 

Emergency Medical Services (EMS)

immediately transported him to Miami Valley 

Hospital. 

WCFD EMS examined two other Veolia 

employees. One, whose hands were cut after he 

jumped a fence topped with barbed wire, was 

treated and released. The second, who 

experienced breathing difficulties, was treated 

with a nebulizer and released. 

One severely injured employee heard the sound 

of a release and detected a very strong odor as 

he left for a meal break in the area south of the 

lab/operations building about three minutes 

before the explosion occurred. He saw a white 

vapor cloud in the dirty tank farm advancing 

toward the lab/operations building. He returned

to the lab/operations building to notify the shift 

supervisor and other personnel, and to retrieve a 

respirator. When the vapor ignited, a bank of 

personnel lockers fell over, briefly pinning the 

employee and breaking his pelvis. 

Unable to walk, the worker sought shelter 

underneath a tractor-trailer after he dragged

himself out of the southwest door of the 

lab/operations building. When he saw flames 
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advancing toward him, he continued his egress 

along the property fence-line on the southwest 

portion of the facility until he found help near 

the administration building about two hours after 

the incident. 

An employee standing at the northwest corner of 

the lab/operations building reported that the 

sound of the release subsided noticeably just 

before the first explosion. He then saw the 

double-doors of the room housing three natural 

gas-fired boilers blow open. (Two of the boilers 

were in service at that time.) A few seconds after 

the first event, he saw a subsequent, larger 

explosion that appeared to originate in the dirty 

tank farm. The worker saw a flame-front that 

extended to the north wall of the drum storage 

building, which exhibited extensive damage 

during post-incident inspections. 

Neighboring property security/surveillance 

media recorded multiple explosions after the 

initial event. These recorded events proceeded 

for roughly 45 minutes after the initial 

explosion. 

3.1 Operations at Time of 

Incident

The plant operators worked 12-hour shifts; day 

shifts started at 5:00 am and night shifts started

at 5:00 p.m. At shift change before the incident, 

the dayshift operator told the nightshift operator 

that something had dislodged in the Unit 3 

evaporator, causing an intermittent rattle in the 

sludge pump during his shift.5 When the day 

shift operator noticed the unusual sound, he

contacted the reclaim supervisor by phone at 

home, who advised him to continue operating 

Unit 3 as outlined in the operating plan unless

the pump was disrupting plant operation. 

 

5

 The CSB investigators discovered that the cause of 

the rattling was a sheared bolt used to secure a 

blade in the evaporator. 

To demonstrate the rattle to the nightshift 

operator coming on shift, the dayshift operator 

pressured nitrogen back through the pump 

suction to the vessel serving as the source of 

material to the pump. 

Immediately prior to the release that led to the 

explosion, the unit operator had commenced the 

shutdown of a tetrahydrofuran (THF) solvent 

recovery process on Unit 3 when test results

indicated that the material had reached the 

desired azeotropic6 state. 

Unit 3 was processing a THF and water mixture 

that was stored in dirty tank 14 (D-14). The 

intent was to recover THF from the mixture for a 

customer. The THF was transferred to a mixing

tank in the clean tank farm where fresh water 

was added re-dilute the mixture to 20 percent 

THF and 80 percent water. The THF and water 

mixture was decanted back to D-14 for 

processing in Unit 3. When the THF and water 

mixture reached its azeotrope of 5.3 percent 

water in THF, further distillation was no longer 

effective in Unit 3 and the recovery process was

transferred to the molecular sieve to break the 

azeotrope and dry the THF to a water content of 

0.03 percent 

 

6

 An azeotrope is the threshold ratio of two or more 

liquids (chemicals) such that simple distillation 

cannot further change their composition. When two 

substances reach azeotrope, the boiled vapor has 

the same ratio of constituents as the original 

mixture. 
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Figure 3. Dirty tank, manifold, and relief systems

After completing the run, the Unit 3 shutdown 

process required clearing the pipe of remaining 

process materials. This was accomplished by 

back-blowing nitrogen through the circulation 

piping into the dirty tank prior to closing valves 

to isolate the tank from the operating unit. The 

vapor release occurred shortly after the unit 

operator started the flow of nitrogen back to the 

dirty tank. 

Employees present at the time of the incident 

reported that, about two minutes before the 

explosion, they heard a loud vapor release. Some

also recalled a very strong THF odor and 

reported the source of the release to be in the 

dirty tank area, which is about 80 feet northeast 

of the three natural gas-fired boilers located in 

the lab/operations building. In addition, they 

reported the vapor drifting back to ground level 

made normal breathing difficult for them. The 

overpowering odor knocked several employees 

to their knees. 

3.2 THF Characteristics

THF, a general purpose, flammable, organic 

solvent, is a colorless, water-miscible, stable

liquid. THF reacts readily with oxygen (e.g., on

contact with air) to form unstable peroxides 

(predominantly hydroperoxides). Adding certain 

stabilizers inhibits the formation of peroxides. 

THF has a flammability rating of 3 in 

accordance with NFPA 704, and is a class 1B 

flammable liquid. 

A solution of THF in water is flammable in 

concentrations of only 0.3 percent. Escaping 

vapors can flow along surfaces to distant 

ignition sources and result in a flashback fire. 

THF vapors form an explosive concentration in

air between 2.3 and 11.8 percent at 20 °C (68

°F). As a liquid, THF is less dense than water, 

and THF vapors are heavier than air.
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Transportation, handling, and storage 

precautions for THF urge the exclusion of 

atmospheric oxygen. THF guidance also 

suggests that reducing water content from THF

or THF mixtures can leave behind high-boiling 

inhibitors and concentrated peroxides, which 

increase the possibility of violent explosions. 

Many incidents associated with the distillations 

of peroxidizable materials occur when peroxides 

become concentrated in distillation residue. 

However, dilution, frequent peroxide testing, 

and nitrogen flushing reduce the hazards.7

Veolia procedures for THF recovery in Unit 4 

included safeguards to prevent peroxide 

formation such as purging with nitrogen, testing

for peroxides every two hours, and adding 

inhibitor as needed. Pure processed THF was 

stored in a clean tank and could be isolated with 

valves from the vapor balance line. Under 

normal operations, the water concentration in 

Unit 3 could not drop below the azeotrope of 5.3 

percent water. Given that the THF was not 

concentrated beyond the azeotrope during this 

distillation phase, precautions for peroxide 

formation were not included in the Unit 3 

operating procedure. 

3.3 Relief Systems

The U.S. Chemical Safety Board (CSB) 

concluded that uncontrolled venting allowed 

vapors to accumulate to explosive 

concentrations outside process equipment. Relief 

valves and rupture disks protected equipment in 

Units 1, 3, and 4 and relieved to the atmosphere. 

A two-inch pressure/vacuum vent relief device

provided protection for “normal breathing” 

when pressure exceeded 0.5 psig or vacuum 

exceeded 1.55 mmHg for each tank in the dirty 

and clean tank farms. This device relieved 

pressure whenever an unbalanced transfer 

occurred or brought in ambient air to avoid tank 

collapse under negative pressure. On the dirty 

 

7

 BASF. “Tetrahydrofuran (THF) Storage and 

Handling,” BASF Corporation Chemicals 

Division, 1998. 

tanks, 18-inch "long-bolt" manways8

 provided 

emergency venting. The weight of the manway 

cover kept the opening sealed against the gasket. 

When pressure developed to lift the cover, the 

bolts allowed the cover to lift at least 1.5 inches. 

Both of these relief devices vented directly to

the atmosphere. 

All relief valves and rupture disks for pressure 

vessels relieved directly to the atmosphere. Units 

3 and 4 rupture disks were oriented upward

toward the north while the relief valves vented

to the east or the north. Tanks and vessels that 

suffered the most severe damage were located 

near the D-14 tank that served as the source of 

feed to Unit 3. The unit operator blew nitrogen 

into this tank just prior to the release. 

 

8

 A manway is a large opening at the top of the tank 

to allow access.
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4.0 Consequences

4.1 Onsite Damage

Most of the buildings on the site were 

constructed of steel frames with metal siding. 

Overpressure damage to these buildings was 

extensive, most notably to the decant building, 

located about 75 feet due east of the likely 

source of the release. Overpressure forces hit the 

steel frames on the western side of this building 

with such force that their anchoring tore loose 

from the foundation and deflected to the east.

The explosion and fire damaged all buildings 

and operating units at the site. These areas 

included the administration, drum storage, 

decant storage, maintenance, and non-hazardous 

waste processing buildings, and Units 1, 3 and 4, 

where several dirty tanks were destroyed. The 

tops of two stainless steel clean tanks also blew

off during the incident. 

Solvent mixtures spilled from the damaged tanks 

and pooled under the dirty tanks. Tank legs in 

the area immediately east of Unit 3 sagged from 

the intense heat generated by the pool fire that 

erupted after the flammable vapor ignited. 

Several tanks appear to have toppled due to the 

intense heat. When falling over they released 

material that fueled a pool fire, which extended 

the burn time of the fire. 

The lab/operations building, which is likely the 

point of origin for the initial ignition of 

flammable vapor, was also severely damaged. 

The interior of the structure displayed minimal 

fire damage based on post-incident inspection; 

however, the masonry block, drywall, and doors 

in the boiler room deflected in an outward 

direction from the center of the room (Figure 4). 

Walls throughout the structure were similarly

oriented outward, including most of the exterior 

south wall of the lab/operations building. Roof 

panels above the boiler area blew upward. The 

north side of the building, directly facing the 

operating plant, remained intact with the 

exception of the northeast corner, which was due 

south of the suspected source of the release

(Figure 2). 

The Veolia facility has a water storage tank 

intended for use during a fire, which normally

contains about 500,000 gallons of water. 

Rendered inoperative due to ruptured pipes, the 

system failed to suppress the fires

Figure 4. Boiler and locker room damage

4.2 Community Damage

The West Carrollton Code Enforcement Officer 

and company records estimate that about 20 

residences sustained damage from the explosion. 

Residents reported broken windows, bent garage 

doors, and chimney detachment. The Code 

Enforcement Officer condemned the garage of 

one residence. About five neighboring 

businesses also sustained damage. One local 

business less than a quarter-mile away suffered

extensive damage, including cracked masonry 

block walls, broken windows, cracked walls, 

misaligned doors, broken ceiling light fixtures,

foundation shift, bent steel framing, and fallen 

ductwork. Some offices displayed damage, 

suggesting workers may have been injured had 

they been present at the time of the explosion. 

Preliminary estimates, including lost production, 

property damage, and business disruption, place 

total costs at about $27 million. 
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Figure 6. Neighboring business office damage Figure 5. Residential damage

5.0 Emergency Response

The WCFD dispatch center received the first 

9-1-1 calls at 12:07 a.m. on Monday, May 4, 

2009. Engine and truck companies from the 

WCFD were the first to respond. Upon arrival, 

WCFD officers immediately activated the 

National Incident Command System (NIMS) 

and assigned roles and responsibilities to 

manage the incident. All responding 

jurisdictions were conversant and compliant 

with NIMS, and all facets of the response were 

conducted through a multi-jurisdictional Unified 

Command Structure with no reported logistical, 

jurisdictional, or communication issues. 

Shortly after their arrival, West Carrollton 

responders directed a request to the Montgomery 

County Sheriff’s Office Foam Bank9

Mutual aid response to the incident included: 

 to help

extinguish the fire in the dirty tank area. Based 

on air sampling and observations, responders did 

not issue a shelter-in-place during the response 

to this incident. 

• Miami Township Fire Department 

• Moraine Fire Department 

• Miamisburg Fire Department

• Dayton Regional Hazardous Material 

(HazMat) trailer and foam truck

 

9

 A foam bank is a storage system that maintains a 

supply of fire-fighting foam intended for use by a 

network of firefighting agencies.

Other responding agencies included

• U.S. EPA 

• Ohio State EPA

• Ohio State Fire Marshal

• Occupational Safety and Health 

Administration (OSHA)

• U.S. Department of Homeland Security 

• Department of Power and Light 

• Vectren (gas supplier)

• Jefferson Regional Water

Due to environmental concerns, responders 

allowed the fires on the Veolia property to burn 

without applying water because of the proximity 

of the facility to a nearby creek and the high area 

water table. Firefighters applied foam at about 

10:00 a.m. the next day to extinguish the 

remaining fires in the dirty tank farm.10

The EPA, notified by the National Response 

Center, deployed a trailer to sample the air 

around the perimeter of the plant, and found no 

hazardous concentrations of toxins. 

 

 

10 Ohio State Fire Marshal’s Office report.
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6.0 OSHA PSM Standard

In a post-incident inspection, OSHA issued 

citations for numerous violations of the Process 

Safety Management (PSM)

11

The citations alleged that the company failed to 

conduct compliance audits every three years to 

ensure that policies and procedures were in place 

for the handling of flammable liquids. They also 

cited worker training deficiencies, inadequate 

testing and inspections of piping and processes, 

a lack of written standards for operating 

procedures, maintaining mechanical integrity of 

equipment, and other items involving process 

safety.

 Standard. The 

OSHA PSM Standard (29 CFR 1910.119) 

requires employers to prevent or minimize the 

consequences of catastrophic release of highly 

hazardous chemicals as well as flammable 

liquids and gases. Hexane and acetone are listed 

chemicals, and Unit 4 processed more than the 

threshold quantity so the PSM standard applied. 

 

11 Process Safety Management is a regulation

promulgated by the U.S Occupational Safety and 

Health Administration (OSHA). A process is any 

activity or combination of activities including any 

use, storage, manufacturing, handling or the on-site 

movement of Highly Hazardous Chemicals 

(HHCs) as defined by OSHA and the 

Environmental Protection Agency. 

7.0 Findings

7.1 Veolia 

• The vent devices were not designed to 

contain or control hazardous and/or toxic 

vapor. 

• Two natural gas-fired boilers were in service 

in the lab/operations building at the time of 

the incident and most likely provided the 

ignition source. 

• The lab/operations building, which housed 

the source of the ignition, was located about 

30 feet south of the operating plant and 

served as a mixed-use structure, which was 

occupied primarily by non-essential 

personnel throughout the day shift. 

• The operating plant had an electrical 

classification of Class 1, Division 112

• No record existed of a process hazard 

analysis (PHA) to evaluate the siting of the

lab/operations building so close to the 

operating units. 

 and 

was compliant with electrical code 

requirements. However, the lab/operations 

building was not classified under the 

National Electrical Code (NFPA 70). 

• The two most seriously injured workers 

were in the lab/operations building at the 

time of incident. While one worker was 

attempting to mitigate the vapor release in 

the plant, the second was donning personal 

protective equipment (PPE) to assist in the 

effort.

 

12 NFPA 70, National Fire Protection Association 

National Electric Code designation for the location 

and necessary protection of electrical equipment in 

areas where flammables are likely to exist.
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Figure 7. Roof and north wall of lab/operations 

building and boiler room

8.0 Analysis

8.1 Overpressure Event

The CSB was unable to determine conclusively 

the cause of the overpressure event due to the

extensive damage in the process area. Based on 

employee observations and the characteristics of 

the materials being processed, two possible 

scenarios could have resulted in a release of 

flammable vapor during the nitrogen blowback 

process: 

• Accumulated THF residue containing 

peroxides suddenly became active when

exposed to oxygen through the vacuum 

breaker or long-bolt manway. 

• The line to the dirty tank was inadvertently 

mis-manifolded prior to the nitrogen

blowback, resulting in the pressurization of 

a nearby dirty tank containing unprocessed, 

flammable, or peroxide-containing liquid. 

8.2 NFPA

The National Fire Protection Association 

(NFPA) is an international, nonprofit 

organization that develops, publishes, and 

disseminates more than 300 consensus codes 

and standards intended to minimize the 

possibility and effects of fire and other similar 

risks. NFPA also provides research, training, and 

education and has a membership of over 75,000 

individuals around the world. 

NFPA codes and standards are widely adopted 

because they are developed using an open, 

consensus-based process, in accordance with 

American National Standards Institute standard 

development process. Volunteer committee 

members, with a wide range of professional 

expertise develop and review all NFPA codes 

and standards.

Currently, there are no industry standards 

available to TSDF owners, permitting agencies, 

and local fire officials to establish safety 

requirements addressing fire and similar risks. 

While the NFPA does publish occupancy 

standards for many industrial facility types (e.g., 

NFPA 820, Standard for Fire Protection in 

Wastewater Treatment and Collection

Facilities), there is no standard specific to 

TSDFs.

NFPA 30, Combustible Liquids Code, applies to 

the storage, handling, and use of flammable and 

combustible liquids. As defined by NFPA 

Section 3.3.6.1, Veolia considered the 

lab/operations structure an “important building.” 

An important building is an occupied structure 

where egress within two minutes cannot be 

reasonably expected, or process control 

buildings that require skilled personnel for the 

orderly shutdown of important or hazardous 

processes.13

• Once the unit operator discovered the 

release, he began efforts to mitigate the leak 

by approaching shut-off valves located in 

the plant, but could not because of the 

overpowering odor of the released material. 

If the lab/operations building had a 

centralized shutdown capability and was 

located farther away from the operating 

plant, the unit operator would have been 

 

13 NFPA 30, Flammable and Combustible Liquids 

Code, Annex A.
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able to conduct a safe and orderly shutdown 

of the plant. 

NFPA 30, Section 22.4.1.1, guidance for control 

room location, allows for siting as close as 10 

feet to an operating unit processing “stable 

combustible liquids.” 

• While Veolia appeared to be compliant with 

NFPA guidance for stable combustible 

liquids using Class 1, Division 1 guidance 

for the operating units, the location of the 

electrically unclassified lab/operations

building less than 30 feet away provided 

multiple potential ignition sources

(including three-fired boilers) for any 

released material.

8.3 Center for Chemical Process 

Safety (CCPS)

The Center for Chemical Process Safety 

(CCPS)is a division/directorate of the American 

Institute of Chemical Engineers, which is a 501 

(c)(3) not for profit educational organization. 

The organization identifies and addresses 

process safety needs within the chemical, 

pharmaceutical, and petroleum industries

through the development of best practice 

guidelines to prevent or mitigate catastrophic 

chemical releases. The CCPS publication, 

“Guidelines for Evaluating Process Plant 

Buildings for External Explosions and Fires,” 

provides guidance for siting buildings in areas 

processing Class 1B liquids. All criteria listed in 

an example for Class 1B liquids would have 

been met by Veolia under the summary 

statement that “a long and successful operating 

history exists to support the low explosion 

potential of NFPA Class 1B flammable liquids 

when handled under the conditions indicated.”14

These criteria state that explosions are extremely 

unlikely because: 

 

14 Center for Chemical Process Safety, Evaluating 

Process Plant Buildings for External Explosions 

and Fires, New York, 1996.

• Potential for a vapor cloud explosion (VCE) 

is low due to the inherent properties of Class 

1B liquids under storage and release 

conditions (lack of confinement, congestion, 

and release of material under low pressure). 

– However, at the West Carrollton facility, 

considerable congestion and 

confinement was created by tanks, 

pumps, and related equipment. 

• The material being released has no potential 

for chemical reactions or for condensedphase explosions. 

– However, the materials processed at the 

West Carrollton facility sometimes had 

the potential for chemical reaction.

• In addressing the fact that the potential for 

explosions cannot be entirely eliminated, a 

reliance on alarms and operating procedures 

along with procedures to minimize potential 

ignition sources was considered sufficient. 

– However, the electrically unclassified

lab/operations building was close 

enough to the plant to provide the initial 

source of ignition for the incident. 
Veolia ES Technical Solutions, L.L.C. Case Study JULY 2010

14

9.0 Recommendations

9.1 Veolia ES Technical 

Solutions

2009-10-I-OH-R1

During the rebuild of the plant, revise policy to 

restrict occupancy of non-essential personnel in 

buildings in close proximity to operating plants. 

2009-10-I-OH-R2

During the rebuild, design and install a closed 

relief system and develop a policy for safe 

venting (e.g., use of a flare) for relief systems to 

the atmosphere. 

2009-10-I-OH-R3

Conduct a process hazard analysis on all OSHA 

Process Safety Management covered processes 

to ensure all buildings and structures at the West 

Carrollton facility are located and designed in 

accordance with electrical classification and 

spacing as defined in NFPA 70. 

9.2 NFPA

2009-10-I-OH-R4 

Revise NFPA 30, Chapter 17, to include a 

section requiring a written engineering analysis 

to determine the safe separation distance for 

occupied buildings, control rooms, and operating 

areas. The analysis must be acceptable to the 

authority having jurisdiction.

9.3 Center for Chemical Process 

Safety (CCPS)

2009-10-I-OH-R5 

Revise control room siting guidelines to reflect 

the diversity of characteristics that Class 1B 

flammable liquids can exhibit (e.g., heavy vapor,

and plant areas that provide congestion and 

confinement). 

9.4 Environmental Technology 

Council

2009-10-I-OH-R6

(Supersedes 2007·01·I·NC·R2)

Petition the National Fire Protection 

Association, following the guidelines of their 

"Codes and Standards Development Process" 

(www.nfpa.org), to develop an occupancy 

standard specific to hazardous waste treatment, 

storage, and disposal facilities. The purpose of 

the standard would be to prescribe technical 

requirements for the safety to life and property

from fire, explosion, and release; and to 

minimize the resulting damage from a fire, 

explosion, and release. At a minimum, but not 

limited to, the standard should address:

• Hazard Identification 

• Chemical Fire and Release Protection and 

Prevention 

• Facility and Systems Design

• Employee Training and Procedures 

• Inspection and Maintenance

2009-10-I-OH-R7 

(Supersedes 2007·01·I·NC·R3)

Develop and issue standardized guidance for the 

processing, handling and storage of hazardous 

waste to reduce the likelihood of fires, 

explosions, and releases at hazardous waste 

treatment storage and disposal facilities. Include 

the incident findings, consequences, 

conclusions, and recommendations from the

CSB investigations of the Environmental 

Quality facility and the Veolia ES Technical 

Solutions.
Veolia ES Technical Solutions, L.L.C. Case Study JULY 2010

15

The U.S. Chemical Safety and Hazard Investigation Board (CSB) is an independent Federal agency 

whose mission is to ensure the safety of workers, the public, and the environment by investigating and 

preventing chemical incidents. The CSB is a scientific investigative organization; it is not an enforcement 

or regulatory body. Established by the Clean Air Act Amendments of 1990, the CSB is responsible for 

determining the root and contributing causes of accidents, issuing safety recommendations, studying 

chemical safety issues, and evaluating the effectiveness of other government agencies involved in 

chemical safety. 

No part of the conclusions, findings, or recommendations of the CSB relating to any chemical accident 

may be admitted as evidence or used in any action or suit for damages. See 42 U.S.C. § 7412(r)(6)(G). 

The CSB makes public its actions and decisions through investigation reports, summary reports, safety 

bulletins, safety recommendations, case studies, incident digests, special technical publications, and 

statistical reviews. More information about the CSB is available at www.csb.gov.

CSB publications can be downloaded at 

www.csb.gov or obtained by contacting:

U.S. Chemical Safety and Hazard 

Investigation Board

Office of Congressional, Public, and Board Affairs

2175 K Street NW, Suite 400

Washington, DC 20037-1848

(202) 261-7600

CSB Investigation Reports are formal, 

detailed reports on significant chemical 

accidents and include key findings, root causes, 

and safety recommendations. CSB Hazard 

Investigations are broader studies of significant 

chemical hazards. CSB Safety Bulletins are 

short, general-interest publications that provide 

new or noteworthy information on 

preventing chemical accidents. CSB Case 

Studies are short reports on specific accidents 

and include a discussion of relevant prevention 

practices. All reports may include safety 

recommendations when appropriate. CSB 

Investigation Digests are plain-language 

summaries of Investigation Reports.