Oak Creek Power Plant
OCA Update and Hazard Review
Ammonia Tank Farm Relocation
Final 09/24/2012
ChemReport
Risk Management Plan
Revised OCA and Hazard Review
Ammonia Tank Farm Relocation
Oak Creek Power Plant
(OCPP)
1.0
Scope
ChemReport Incorporated, an environmental and safety engineering firm, was retained by
We Energies to update the existing Risk Management Plan (RMP) for the Oak Creek Power
Plant (OCPP) in response to the permanent relocation of the ammonia storage tank farm
subsequent to a bluff failure that occurred on October 31, 2011. The OCCP facility is located
at 11060 South Chicago Road in Oak Creek, Wisconsin (See Appendix A for a map of the
location). The original RMP was developed for the use and storage of aqueous ammonia
used in the facility’s Selective Catalytic Reduction (SCR) system to control NOx emissions
and all other elements of the original RMP remain applicable. However, due to the
permanent relocation of the ammonia storage tank farm, the following elements of the RMP
have been revised:

Offsite Consequence Analysis (OCA)

Process Hazard Analysis (PHA)
2.0
Background
The OCPP facility is regulated under the RMP regulations as a Program Level 2 Facility. The
SCR system consists of two reaction chambers installed with Boilers 5 and 6 ducted to one
SCR chamber and Boilers 7 and 8 ducted to the second SCR chamber. The SCR Project, as
originally constructed in 2010 and 2011, utilized two 20,000 gallon above-ground storage
tanks for the planned storage of aqueous ammonia at a concentration of approximately 29
percent.
The initial RMP was developed and finalized on July 20, 2011. Approximately three (3)
months later, on October 31, 2011, a ravine on the OCPP site, which had been filled with fly
ash in the 1960s, collapsed sending a mixture of fly ash and soil down the bluff.
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The bluff failure undermined the foundation of the storage pad for the ammonia storage
tanks, rendering the ammonia tank farm unusable. At the time of the bluff failure, the
ammonia storage tanks were empty and there was no threat of an ammonia release.
As the tank farm was unusable after the bluff failure, a temporary ammonia storage system
was designed using a staged tanker truck for ammonia storage until the tank farm could be
permanently relocated. In preparation for the use of the temporary tanker truck storage
system, the OCA and PHA were updated and revised on December 13, 2011.
While the temporary ammonia tank truck system was being used, construction began on the
permanent ammonia storage tank farm which was completed in August of 2012. As the
relocation of the ammonia storage tank farm constitutes a major process change, the RMP is
being updated with the following revised OCA and PHA.
3.0
System Design and RMP Elements
ChemReport met with We Energies on July 9, 2012 to discuss any physical or operational
changes from the original design of the ammonia storage tank farm and conducted a visual
tour of the newly reconstructed system. According to Jim Petersen of We Energies, all
aspects of the original tank farm design, specifications and operating parameters used for
the original 2010–2011 tank farm were reused for the permanent storage tank farm, including
all safety systems and DCS operating parameters.
The only change associated with the newly relocated permanent installation is the amount of
ammonia contained in the piping run to the SCR system since the new tank farm has been
located further away. (See Appendix B for the new tank farm location.) Due to the additional
volume of ammonia and changed location of the tank farm, an updated Offsite Consequence
Analysis (OCA) was performed by ChemReport.
The original Process Hazard Analysis (PHA) did not need to be fully revised as the
permanent ammonia storage tank farm has been constructed according to the original tank
farm specifications, using the same equipment and operational procedures. The original
distribution system was only changed to provide more piping to reach the more remote
location of the tank farm. The SCR system components (e.g. injection lances, DCS logic,
etc.) remain the same.
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Ammonia Tank Farm Relocation
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We Energies did however conduct the necessary evaluation(s) of the geological conditions
associated with the permanent tank farm area to ensure that it was not prone to future failure
and also evaluated the integrity of the reused ammonia storage tanks and associated system
components. This documentation is on file at We Energies and is separate from the RMP
documentation.
The PHA was updated for the construction of the final ammonia storage tank farm installation
as described in Section 15.0 of this document.
4.0
Threshold Determination
The OCPP SCR system uses aqueous ammonia (ammonia) in the SCR system at an
approximate concentration of 29%. Two 20,000 gallon, diked, above-ground storage tanks
are used to store the ammonia on-site. The ammonia is distributed to the SCR system
through piping consisting of various diameters (1-1/2”, 1”, and 3/4”) equaling a volume of
approximately 650 gallons when the piping system is full.
Each 20,000 gallon storage tank is controlled by the facility’s Distributive Control System
(DCS) and operational procedures limiting tank filling to no more than 95% of the tank’s
capacity, resulting in a maximum tank volume of 19,000 gallons per tank. At an approximate
weight of 7.66 pounds per gallon, the maximum amount of ammonia in either tank is 145,540
pounds.
The total amount of aqueous ammonia that can be contained within the entire relocated
ammonia storage tank farm is calculated as follows:
Table 1
Ammonia Threshold Determination
Tanks:
145,540 lbs/tank x 2 tanks
=
291,080 lbs
Piping:
650 gals x 7.66 lbs/gal
=
4,979 lbs
Total Maximum Ammonia in SCR System
=
296,059 lbs
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5.0
ChemReport
RMP Program Levels
The OCPP facility remains classified as a Program Level 2 facility. The complexity of the
RMP is based on one of three possible Program Levels as follows:
1
Processes with no public receptors within the distance to a toxic
endpoint concentration from a modeled worst-case release scenario are
eligible for Program Level 1 provided that no significant accidents
involving a regulated substance have occurred within the last five years.
Program Level 1 facilities must comply with limited hazard assessment
requirements and minimal prevention and emergency response
requirements.
2
Processes that are not eligible for Program Level 1 or are not subject to
Program Level 3 are placed into Program Level 2. Program Level 2
facilities must comply with more streamlined prevention program
requirements, as well as additional hazard assessment, management,
and emergency response requirements.
3
Any process that is not eligible for Program Level 1 and is subject to
OSHA's Process Safety Management (PSM) Standard under 29 CFR
1910.119 is subject to Program Level 3 requirements. Program Level 3
facilities must comply with both the OSHA PSM standard and the U.S.
EPA
RMP
rule.
Program
Level
3
facilities
must
develop
a
comprehensive chemical release prevention program and comply with
additional requirements concerning process hazard assessments,
management techniques, and emergency response requirements.
The worst-case release modeling analysis results (discussed in Section 9.0 of this report) for
aqueous ammonia show that the distance to a toxic endpoint concentration under a rural
land classification is 1.5 miles. This distance exceeds the plant's property boundaries and
impacts off-site public receptors. Consequently, the OCPP facility is ineligible for Program
Level 1. Additionally, the OCPP facility is not subject to OSHA’s Process Safety
Management (PSM) requirements under 29 CFR 1910.119. The threshold for PSM
regulation for aqueous ammonia is 15,000 pounds of aqueous ammonia meeting or
exceeding 44% in concentration. The aqueous ammonia used at OCPP is only 29% in
concentration.
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The original review of chemical substances in inventory at OCPP in June of 2011 showed no
other substances were present in amounts that would subject the OCPP facility to the PSM
requirements and no new substances have been introduced at the facility since that time
according to We Energies personnel.
As the OCPP facility is ineligible for a Program Level 1 designation due to the distance to a
toxic endpoint concentration and is not subject to OSHA's Process Safety Management
(PSM) Standard, the OCPP facility remains classified as a Program Level 2 Facility under
the RMP rule.
ChemReport has conducted this update of the OCA and PHA in accordance with the
Program Level 2 requirements of the RMP rule. The SCR system is comprised of two main
components or sub-processes. The first component is the storage of aqueous ammonia and
its delivery system to the SCR operating system. The second component is the SCR
operating system itself. Both components are considered to be a single process under the
RMP Rule and as such, all aspects of this plan take into account the operation of the entire
process.
6.0
Facility and Process Description
The OCPP facility is located directly adjacent to Lake Michigan, straddling both Milwaukee
and Racine Counties. The location and plant layout of the OCPP facility are contained in
Appendix A.
The original two 20,000 gallon aqueous ammonia storage tanks are mounted on top of
concrete saddles located within a concrete containment dike. The original dike measured
approximately 2,000 square feet (40’ x 50’) with a depth of 2.75 feet equating to a total
volume of 5,500 cubic feet. After subtracting the volume of the concrete saddles (545 cubic
feet), the total amount of containment available was 4,955 cubic feet or 37,063 gallons
(4,955 x 7.48) of liquid material. The relocated ammonia storage tank farm has been
constructed by adding an additional three (3) feet of length to the original dike dimensions
resulting in an additional 500 cubic feet of containment or 3,740 gallons for a total
containment volume of 40,803 gallons.
The truck unloading pad does not have curbed containment. However, the pad is sloped
toward the middle where an open sewer grate would direct any discharge directly to the tank
farm containment dike via an underground 6-inch drain.
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Ammonia Tank Farm Relocation
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ChemReport
The latitude and longitude for the OCPP facility (centered on the ammonia storage tank farm)
were identified using Marplot Version 4.2.2 geospatial mapping software developed jointly by
the EPA and the National Oceanic and Atmospheric Administration (NOAA) which place the
coordinates at latitude 42o 50' 30” North and longitude -87o 49’ 46" West. The location of the
ammonia storage area is shown in Appendix B.
According to the North American Industrial Classification System (NAICS), the OCPP facility
continues to fall within major industrial grouping "22" with an assigned NAICS Code of
221112.
7.0
Land Use Classification
ChemReport previously evaluated the predominant land use surrounding the facility for the
purpose of determining whether urban or rural dispersion coefficients should be used when
modeling various release scenarios in June of 2011. A review of this analysis by
ChemReport showed it to remain current. The Auer (Auer, 1978) Land Use Classification
Scheme was used for this purpose according to the criteria detailed in Table 2 below.
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Table 2
Identification and Classification of Land Use Types
Type
Use and Structures
Vegetation
Heavy Industrial: Major chemical, steel and
I1
fabrication industries; generally 3-5 story
buildings, flat roofs
Grass and tree growth extremely rare;
< 5% vegetation
Light-Moderate Industrial: Rail yards, truck
I2
depots, warehouses, industrial parks, minor
Very limited grass, trees almost totally
fabrications; generally 1-3 story buildings, flat
absent; < 5% vegetation
roofs
C1
Commercial: Office and apartment buildings,
hotels; >10 story heights, flat roofs
Common Residential: Single family dwellings
R1
with normal easements; generally one story,
pitched roof structures; frequent driveways
Limited grass and trees; < 15% vegetation
Abundant grass lawns and light-moderately
wooded; > 70% vegetation
Compact Residential: Single, some multiple,
R2
family dwellings with close spacing; generally
Limited lawn sizes and shade trees;
<2 story, pitched roof structures; garages (via
< 30% vegetation
alley), no driveways
Compact
R3
Residential:
Old
multi-family
dwellings with close (<2 m) lateral separation;
Limited lawn sizes, old established shade
generally 2 story, flat roof structures; garages
trees; < 35% vegetation
(via alley) and ash pits, no driveways
R4
Estate Residential: Expansive family dwellings
Abundant grass lawns and lightly wooded;
on multiple-acre tracts
> 80% vegetation
Metropolitan Natural: Major municipal, state,
A1
or federal parks, golf courses, cemeteries,
campuses; occasional single story structures
A2
Agricultural Rural
A3
Undeveloped: Uncultivated; wasteland
A4
Undeveloped Rural
A5
Water Surfaces: Rivers, lakes
Nearly total grass and lightly wooded
> 95% vegetation
Local crops (e.g., corn, soybean);
> 95% vegetation
Mostly wild grasses and weeds, lightly
wooded; > 90% vegetation
Heavily wooded; > 95% vegetation
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A three (3) kilometer radius centered at the OCPP facility was superimposed on the aerial
photograph used to determine the facility’s latitude and longitude. This figure was then used
to evaluate all land uses within the circle exhibiting the characteristics of I1, I2, C1, R2 and
R3 classifications per the Auer criteria. These classifications were then shaded to indicate an
urban setting.
As illustrated in Appendix C, the urban land use within the three kilometer radius of the
facility is less than 25%, well below the 50% threshold used to determine the predominant
land use for dispersion modeling. Consequently, the predominant land use setting for the
OCPP facility was determined to be “rural” for dispersion modeling purposes which remains
current through August of 2012.
Prior reconnaissance of the area was performed by ChemReport in June of 2011 to confirm
interpretations made on the site imagery. New surveillance was conducted in July of 2012 to
assess any significant new developments that may have occurred in the vicinity of the
facility. While a few residential structures were noted to be under construction, they were
determined to not be significant enough to shift the land use classification above the 50%
threshold.
8.0
Climatological Parameters
ChemReport evaluated local climatological conditions for the last 36 months to be used as
data inputs for the release modeling scenarios. Data for this evaluation was obtained from
the National Oceanic and Atmospheric Administration’s (NOAA) weather station located at
the Mitchell International Airport in Milwaukee, Wisconsin. NOAA annual summary data was
available for 2010 and 2011. To complete the data set needed for the most recent 36
months, NOAA monthly data was used for August through December of 2009, and January
through July of 2012. Meteorological data for the last 36 months is summarized in Table 3
below.
[ This Section Intentionally Left Blank ]
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Table 3
NOAA Climatological Data
3-Year Annual Averages and Maximums
% Relative
Humidity
Temp oF
Max
Temp oF
AVG
Wind (mph)
AVG
Aug 2009
68.0
90.0
68.8
8.6
Sep 2009
73.0
85.0
63.9
6.2
Oct 2009
72.0
69.0
48.3
9.7
Nov 2009
71.0
71.0
44.9
8.3
Dec 2009
73.0
51.0
26.4
10.2
2010
68 / 816.0*
92.0
50.3 / 603.6*
9.0 / 108.0*
2011
70 / 840.0*
98.0
48.6 / 583.2*
9.4 / 112.8*
Jan 2012
69.0
55.0
28.4
9.9
Feb 2012
70.0
53.0
31.2
9.4
Mar 2012
67.0
84.0
48.8
10.4
Apr 2012
65.0
74.0
46.3
10.3
May 2012
62.0
90.0
61.0
9.2
Jun 2012
57.0
96.0
81.3
9.5
Jul 2012
65.0
103.0
87.3
8.3
Date
Data Summary For Dispersion Modeling (Bold Font)
Average
68.6
-
50.7
9.2
Maximum
73.0
103.0
-
10.4
Minimum
57.0
-
-
6.2
Data Source(s):
* Annual average multiplied by 12 to obtain weighted datum
Annual Local Climatological Data – NOAA, National Climatic Data Center
Monthly Data – National Weather Service, Monthly Data Summary
General Mitchell International Airport (MKE)
Milwaukee, WI – WBAN: 14839
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Atmospheric stability classifications of “F” and “D” were used for the worst-case and
alternative-case modeling scenarios, respectively. U.S. EPA requires that worst-case
modeling scenarios use an atmospheric stability classification of “F” which represents the
most stable atmospheric conditions and provides for the most conservative distance to a
toxic endpoint concentration.
ChemReport used the RMP standard defaults of “F” and “D” because site-specific
atmospheric stabilities could not be accurately determined. Atmospheric stabilities are based
on minimum wind speed and cloud cover as indicated in Table 4 taken from the User’s
Manual for the Aerial Locations of Hazardous Atmospheres (ALOHA) dispersion modeling
software program used by ChemReport to determine the distances to toxic endpoint
concentrations for the OCPP facility.
Table 4
ALOHA Atmospheric Stability Chart
Surface Wind Speed
DAY TIME
NIGHT TIME
Incoming Solar Radiation
Cloud Cover
Strong
Moderate
Slight
> 5/10
< 5/10
Miles per hour
Meters per second
<4
<2
A
A-B
B
E
F
4 to 7
2 to 3
A-B
B
C
E
F
7 to 11
3 to 5
B
B-C
C
D
E
11 to 13
5 to 6
C
C-D
D
D
D
> 13
>6
C
D
D
D
D
Facility cloud cover for the 36 month time frame needed for modeling was not available to
determine a specific atmospheric stability rating. As a result, the default value of
“F” was used for the worst-case release scenario and default value of “D” was used for the
alternative-case scenario.
In addition to using atmospheric stability ratings for dispersion modeling in ALOHA, the
software program requires additional inputs for cloud cover. The “F” stability classification
used for the ALOHA worst-case modeling analysis assumed a conservative worst-case cloud
cover value of zero (no cloud cover). The “D” stability classification used for the alternativecase analysis assumed an average cloud cover value of 50%. The meteorological
parameters used for all modeling are summarized in Table 5 below.
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Table 5
ALOHA Meteorological Modeling Parameters
Conditions
Worst-Case
Alternative-Case
Wind Speed
1.5 meters/second
3.0 meters/second
Assumed Wind Direction
From West
From West
EPA Stability Rating
F
D
Cloud Cover
0
50%
Temperature/Humidity
103F + 69% RH
50.7F + 69% RH
Liquid Temperature
103F
50.7F
ALOHA allows for additional meteorological data to be input into the model for inversions. An
inversion is an atmospheric condition in which an unstable layer of air near the ground lies
beneath a very stable layer of air above. The height of the abrupt change of atmospheric
stability is called the inversion height. An inversion can trap pollutant gases below the
inversion height. This may cause ground-level concentrations of a pollutant to reach higher
levels than would otherwise be expected.
The type of inversion of concern for dispersion modeling is a low-level inversion that could
trap a pollutant cloud near the ground. Low ground fog is a good indicator of the presence of
this type of inversion. However, inversions are unpredictable and should only be input into
the ALOHA model for real-time modeling during an actual chemical release. As a result, all
ALOHA modeling was performed without assuming that an inversion existed.
ChemReport used the prevailing westerly wind direction as a default variable only. For RMP
purposes, ALOHA is used to calculate the radius to a toxic endpoint of 0.14 mg/l (200 ppm)
of ammonia. The calculated distance is independent of the wind direction that is input into
the ALOHA modeling program.
ChemReport verified that the wind direction used in the ALOHA model is immaterial by
running the model using several different wind direction inputs with all of them resulting in the
same distance to the toxic endpoint.
The assumption under the RMP program is that during a release, the wind may be blowing
from any direction. This is particularly true during the summer months when diurnal wind
variation is common along Lake Michigan as air that is cooler and more dense above the
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water blows inland from the east off the lake during the day, replacing air over the land that is
warmer and therefore, rising. Cooling at night tends to cause the wind to shift back to the
prevailing direction (west).
As a consequence, the RMP standard requires that a radius be used to define a circle that
encompasses the entire area surrounding the source that may exceed 200 ppm during a
release. The actual area within that circle that would be affected during a release would be
dependent on the wind direction at that time.
9.0
Worst-Case Release Scenario
Worst-case release dispersion modeling was performed on the greatest volume that could be
released from the largest storage vessel and associated SCR system piping. For worst-case
release modeling purposes, ChemReport used the maximum volume of ammonia contained
in a single 20,000 gallon storage tank which was aggregated with the 650 gallons of
ammonia contained in the ammonia piping system, as shown in Table 6 below:
Table 6
Worst-Case Release Scenario Aqueous Ammonia Volume
Gallons
Pounds
Storage Tank:
20,000 gallons @ 95% Full x 7.66 lbs/gal
=
19,000
145,540
Piping:
650 gals x 7.66 lbs/gal
=
650
4,979
=
19,650
150,519
Total Maximum Aqueous Ammonia Release
Under the RMP rule, only the contents of a single and largest vessel and associated piping
within the regulated process containing aqueous ammonia must be modeled. The worst-case
release scenario assumed that the entire contents of the storage tank aggregated with the
entire contents of all associated piping were released into the secondary containment area.
9.1
Worst-Case Release Scenario Modeling
ALOHA Version 5.4.3 (March 2012), the most current version available as of August 2012
was used to perform the modeling of a worst-case release scenario. Although there are
many different release scenarios that can be evaluated in ALOHA, the two primary methods
applicable to the OCPP system are the “direct release” and “puddle release” models.
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With the direct release model, ALOHA uses the chemical properties of pure ammonia vapors
when calculating the distance to a toxic endpoint concentration from the release source. In
order to do this, ALOHA requires that the evaporation rate (in lbs/min) of a puddle formed by
the release into a dike to be manually calculated and entered into the program.
Although the National Oceanic and Atmospheric Administration (NOAA) has developed a
puddle evaporation rate calculator for aqueous ammonia which can be used in ALOHA, it
yields overly conservative distances to a toxic endpoint concentration because it treats the
evaporating vapors as anhydrous ammonia. In actuality, the evaporative properties of
aqueous ammonia solution are vastly different from those of anhydrous ammonia.
While the use of the direct release method is suitable for RMP planning purposes, further
analysis of ALOHA’s capabilities show that the “puddle release” method is more appropriate
for aqueous solutions of ammonia when the puddle has a large surface area such as with the
OCPP secondary containment system of 2,120 square feet calculated as indicated in Table 7
below:
Table 7
Worst-Case Release Scenario Containment Volume
Surface Area (ft2)
Containment Dimensions
Tank Farm Containment
53’L x 40’W x 2.75’H
=
2,120
According to NOAA, ALOHA mathematically treats the “Direct Release Model” as a point
source and states that ALOHA’s results are less accurate when a puddle is very large and
recommends that the user consider a different modeling method in ALOHA.
With the puddle release model, the user enters the concentration of the ammonia solution,
the total area of the puddle, and the puddle’s volume. ALOHA then calculates the
evaporation rate of the puddle as an ammonia solution, eliminating the need for the user to
manually calculate it with NOAA’s evaporation rate calculator. After taking into account all
atmospheric and other source data inputs from the user, the program calculates the distance
to a toxic endpoint concentration.
The ALOHA puddle method has been used by the U.S. Department of Energy for dispersion
modeling of aqueous ammonia solutions and was selected by ChemReport as the most
appropriate method for OCPP. The parameters entered into ALOHA are detailed in Table 8
below.
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Table 8
Worst-Case Release Scenario Modeling Parameters
ALOHA
Modeling Method:
Puddle Release of 29% Aqueous Ammonia
Release Scenario:
Diked Release of Storage Tank and Associated Piping
Release Duration:
ALOHA Default Limited To Duration of 1 Hour
Toxic Endpoint:
0.14 mg/L (200 ppm)
Passive Mitigation Measures:
Dike (2,120 ft2 area)
Active Mitigation Measures:
Not Allowed
Quantity Released:
19,650 gallons (150,519 lbs)
Height of Release:
Ground Level
Dense or Neutrally Buoyant Gas:
Neutrally Buoyant Gas
Wind Speed/Stability:
1.5 Meters per Second (3.4 MPH)
EPA Stability Rating:
F
Cloud Cover:
None (For “F” Stability)
Ambient Temperature/Humidity:
103 oF and 69 % Humidity
Surface Roughness:
Rural Topography
Temperature of Substance:
103 oF
According to the ALOHA puddle model, a worst-case scenario involving the release of the
entire contents of a single aqueous ammonia storage tank and its related piping would result
in a distance of 1.5 miles to the defined toxic endpoint concentration of 0.14 mg/l (200 ppm)
with a rural land use classification. The ALOHA modeling results are indicated below.
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WORST-CASE SCENARIO
SITE DATA:
Location: MILWAUKEE, WISCONSIN
Building Air Exchanges Per Hour: 0.54 (unsheltered single storied)
Time: August 8, 2012 0925 hours CDT (using computer's clock)
CHEMICAL DATA:
Chemical Name: AQUEOUS AMMONIA
Solution Strength: 29% (by weight)
Ambient Boiling Point: 81.0° F
Partial Pressure at Ambient Temperature: greater than 1 atm
Ambient Saturation Concentration: 1,000,000 ppm or 100.0%
Hazardous Component: AMMONIA
Molecular Weight: 17.03 g/mol
AEGL-1 (60 min): 30 ppm AEGL-2 (60 min): 160 ppm AEGL-3 (60 min): 1100 ppm
IDLH: 300 ppm
LEL: 150000 ppm UEL: 280000 ppm
ATMOSPHERIC DATA: (MANUAL INPUT OF DATA)
Wind: 1.5 meters/second from W at 3 meters
Ground Roughness: open country
Cloud Cover: 0 tenths
Air Temperature: 103° F
Stability Class: F (user override)
No Inversion Height
Relative Humidity: 69%
SOURCE STRENGTH:
Evaporating Puddle (Note: chemical is flammable)
Puddle Area: 2120 square feet
Puddle Volume: 19650 gallons
Ground Type: Concrete
Ground Temperature: 103° F
Initial Puddle Temperature: 81° F
Release Duration: ALOHA limited the duration to 1 hour
Max Average Sustained Release Rate: 316 pounds/min (averaged over a minute or more)
Total Amount Hazardous Component Released: 5,960 pounds
THREAT ZONE:
Model Run: Gaussian
RESULTS
5.6 miles
3.5 miles
1.8 miles
1.5 miles
1.2 miles
0.7 miles
--- (25 ppm = ERPG-1)
--- (50 ppm = OSHA TWA PEL)
--- (150 ppm = ERPG-2)
--- (200 ppm = RMP 0.14 mg/l End Point)
--- (300 ppm = IDLH)
--- (750 ppm = ERPG-3)
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Alternative-Case Release Scenario
Alternative-case release scenarios are designed to represent a more realistic scenario of a
potential release that may occur during the operation of the SCR system. Although a
probability analysis of the alternative release scenario does not have to be conducted, a
release scenario that is more probable to occur should be selected.
ALOHA Version 5.4.3 (March 2012), the most current version available as of August 2012
was used to perform the modeling of an alternative-case release scenario using the “puddle
model” as discussed in Section 9.0 on this report.
For alternative-case release scenarios, facilities are allowed to consider active mitigation
systems, such as interlocks, shutdown systems, pressure relieving devices, emergency
isolation systems, and fire water and deluge systems, as well as passive mitigation systems.
The permanent ammonia storage and delivery system has the following mitigation systems
installed:
Passive Mitigation

Diked containment of Ammonia Delivery Pad
Active Mitigation

Emergency shutdown systems located at ammonia pump skid designed to stop the flow
of ammonia from the pumps in the event of a release

Excess flow valve on the delivery trailer designed to stop flow from the trailer if excess
flow is detected

Manned loading operations with associated safety equipment so that rapid on-site
response and containment can be accomplished

Ammonia sensors and alarms located at ammonia pump skid
In order to determine which alternative-case release scenario to utilize for the modeling,
several scenarios were considered by ChemReport and the PHA Team who believed that
the highest potential for a release to occur continues to be during loading activities.
The selection of this scenario is consistent with the original OCPP alternative-case release
scenario evaluated in June of 2011 and is also consistent with alternative-case release
scenarios that have been evaluated at other We Energies facilities that utilize aqueous
ammonia.
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For the OCPP alternative-case release scenario, it was assumed that the unloading hose
from the delivery tanker truck to the storage tank either ruptured or somehow became
detached from its connections. We Energies provided the information associated with
aqueous ammonia delivery by Tanner Industries, the OCPP ammonia supplier in Table 9
below.
Table 9
Ammonia Tanker Truck Parameters
Parameter
Tanner Industries
Release Duration
5 minutes (estimated)
Amount Released
660 gallons (5,056 lbs)
Truck Capacity
6,500 gallons
Delivery Rate
132 gpm
Size And Length of Delivery Hose
2” Diameter – 3 lengths @ 20 feet each
Size And Length of Vapor Return Hose
¾” – 50 feet
Excess Flow Valve on Delivery Line
Equipped with emergency remote control
Vapor Return Via Compressor
Yes
Type of Quick Disconnect (Liquid Line)
Male Evertite
Type of Quick Disconnect (Vapor Line)
Chicago Fitting
Length of The Truck
57’ long x 12’ high x 10’ wide
Height of Hose Connections (Liquid Line)
18 – 36 inches
Height of Hose Connections (Vapor Line)
60 inches
The alternative-case release scenario assumed that a hose became detached during
unloading operations from the delivery trailer and that the release would last for no more
than five (5) minutes.
ChemReport believes the five-minute value is conservative as the truck operator has the
means to stop such a release much sooner, either with remotely controlled valves or through
the use of the tanker’s excess flow valve. Additionally, the unloading operations are
monitored by plant personnel, who are capable to bring such a release under control within
five minutes. The actual time it would take to bring such a release under control is estimated
to be less than two (2) minutes.
Containment for the delivery truck unloading area is provided through a sloped unloading
pad that drains into the storage tank containment structure. For the alternative-case release
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scenario modeling, it was assumed that the truck would release 132 gallons per minute for a
period of 5 minutes into storage tank containment structure for a total release of 660 gallons
(660 gal x 7.66 lb/gal = 5,056 pounds).
10.1
Alternative-Case Release Scenario Modeling
ALOHA’s puddle release model was again used as previously discussed in Section 9.0 of
this report, to determine the distance to a toxic endpoint concentration for the alternativecase release scenario. The parameters entered into ALOHA are presented in Table 10
below.
Table 10
Alternative-Case Release Scenario Modeling Parameters
ALOHA
Modeling Method:
Puddle Release of 29% Aqueous Ammonia
Release Scenario:
Detached Transfer Hose From Truck
Release Duration:
ALOHA Default Limited To Duration of 1 Hour
Toxic Endpoint:
0.14 mg/L (200 ppm)
Administrative Controls:
Manned Operation
Passive Mitigation Measures:
Dike (2,120 ft2 area)
Active Mitigation Measures:
Excess Flow Valve / Alarm System / Operator Shut-Off
Quantity Released:
660 Gallons (132 gpm x 5 minutes)
Height of Release:
Ground Level
Dense or Neutrally Buoyant Gas:
Neutrally Buoyant Gas
Wind Speed/Stability:
3.0 Meters per Second (6.7 MPH)
EPA Stability Rating:
D
Cloud Cover:
50%
Ambient Temperature/Humidity:
50.7 oF
Relative Humidity:
69%
Surface Roughness:
Rural Topography
Temperature of Substance:
50.7 oF
According to the ALOHA model, the alternative-case release scenario involving a five-minute
release from a ruptured or detached tank truck delivery hose would result in a distance of
0.22 miles to the defined toxic endpoint concentration of 0.14 mg/l (200 ppm) within a rural
land use classification. The ALOHA modeling results are indicated below.
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ALTERNATIVE-CASE SCENARIO
SITE DATA:
Location: MILWAUKEE, WISCONSIN
Building Air Exchanges Per Hour: 0.70 (unsheltered single storied)
Time: August 8, 2012 0937 hours CDT (using computer's clock)
CHEMICAL DATA:
Chemical Name: AQUEOUS AMMONIA
Solution Strength: 29% (by weight)
Ambient Boiling Point: 81.0° F
Partial Pressure at Ambient Temperature: 0.47 atm
Ambient Saturation Concentration: 477,064 ppm or 47.7%
Hazardous Component: AMMONIA
Molecular Weight: 17.03 g/mol
AEGL-1 (60 min): 30 ppm AEGL-2 (60 min): 160 ppm AEGL-3 (60 min): 1100 ppm
IDLH: 300 ppm
LEL: 150000 ppm UEL: 280000 ppm
ATMOSPHERIC DATA: (MANUAL INPUT OF DATA)
Wind: 3 meters/second from W at 3 meters
Ground Roughness: open country
Cloud Cover: 5 tenths
Air Temperature: 50.7° F
Stability Class: D (user override)
No Inversion Height
Relative Humidity: 69%
SOURCE STRENGTH:
Evaporating Puddle (Note: chemical is flammable)
Puddle Area: 2120 square feet
Puddle Volume: 660 gallons
Ground Type: Concrete
Ground Temperature: 50.7° F
Initial Puddle Temperature: Ground temperature
Release Duration: ALOHA limited the duration to 1 hour
Max Average Sustained Release Rate: 90.7 pounds/min (averaged over a minute or more)
Total Amount Hazardous Component Released: 1,106 pounds
THREAT ZONE:
Model Run: Gaussian
RESULTS
0.62 miles
0.45 miles
0.26 miles
0.22 miles
0.18 miles
0.11 miles
--- (25 ppm = ERPG-1)
--- (50 ppm = OSHA TWA PEL)
--- (150 ppm = ERPG-2)
--- (200 ppm = RMP 0.14 mg/l End Point)
--- (300 ppm = IDLH)
--- (750 ppm = ERPG-3)
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11.0
ChemReport
Summary and Discussion of Modeling Technique
Table 11 below summarizes the distances calculated by the ALOHA dispersion modeling
program to the predefined toxic endpoint concentration of 0.14 mg/l (200 ppm) for aqueous
ammonia for both the worst-case and alternative-case aqueous ammonia release scenarios.
Table 11
OCPP Facility ALOHA Modeling Summary
Distance To Toxic Endpoint Concentration of 0.14 mg/l (200 ppm)
Scenario
June 2011
August 2012
Original Tank Farm
Relocated Tank Farm
Worst-Case (Rural)
1.5 miles
1.5 miles
Alternative-Case (Rural)
0.21 miles
0.22 miles
U.S. EPA allows regulated entities to utilize a variety of different modeling techniques to
estimate the distance to a toxic endpoint concentration for both the worst-case and
alternative-case release scenarios. The agency recognizes that modeling results can vary
considerably from model to model.
U.S. EPA recommends that more precise chemical release modeling techniques be
considered for use when performing the offsite consequence analysis (OCA) if the regulated
entity has the expertise and data needed to use them, although such techniques are not
required to be used under the RMP rule. Site-specific meteorological conditions have a large
impact when estimating the distance to a toxic endpoint concentration during a release
event. Conditions such as wind speed, temperature, humidity, cloud cover, etc. will greatly
influence the extent of a chemical’s ability to migrate away from the release source. The
preferred modeling technique that takes these factors into consideration, along with
chemical-specific (density, vapor pressure, etc.) and release-specific (diked containment)
factors is ALOHA.
ALOHA is the primary modeling technique used by emergency responders when estimating
impact zones during an actual chemical release emergency as ALOHA is designed to
simulate an actual release under conditions observed at a specific site during a release
event.
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ChemReport
Affected Populations – Worst-Case Release
Marplot Version 4.2.2 (current as of August 2012) mapping software was used to estimate
the population impacts within the 1.5 mile distance to the toxic endpoint concentration of 0.14
mg/L (200 ppm) of ammonia. A circle encompassing a 1.5 mile radius from the center of the
relocated ammonia storage tanks was superimposed on the Marplot map to estimate
populations that could be affected by a worst-case release (See Appendix D). Affected
populations are based on data obtained from the U.S. Census Bureau and linked to the
mapping software program. Population data contained in the mapping system is based on
calendar year 2010 census data which represents the most current population estimates
available from the U.S. Census Bureau.
The "Census Blocks" method of calculation was used to estimate populations affected by the
worst-case release scenario which is the only option available in Marplot 4.2.2 to estimate
populations affected. As the census data does not contain information on populations using
Lake Michigan for recreational purposes (boaters and fishermen), ChemReport developed a
conservative estimate by assuming that 100 boats could potentially be within a 1.5 mile
radius of the OCPP facility with an average of five (5) persons per boat. Additionally, it was
assumed that there would be up to 25 people on the OCPP on-site fishing pier during the
time of the release. A summary of all affected populations is provided in Table 12 below.
Table 12
Affected Populations
ALOHA Worst-Case Release Scenario
Worst-Case Release Scenario
June 2011
August 2012
Original Tank Farm
Relocated Tank Farm
Distance To Endpoint of 0.14 mg/l
1.5 miles
1.5 miles
Population Affected (2010 Census)
638
638
Population Affected (Lake Michigan Boaters)
500
500
Population Affected (Fishing Pier)
25
25
1,163
1,163
Total Population Affected
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12.1
ChemReport
Public Receptors – Worst-Case Release
Marplot Version 4.2.2 (current as of August 2012) mapping software and public information
systems maintained by the United States Geological Survey, Racine and Milwaukee County
Schools, Wisconsin Historical Society, Wisconsin Register of Historical Places, National Park
Service Historical Landmark Survey, Racine and Milwaukee County Parks Systems,
Wisconsin Department of Corrections and aerial photographs provided by the Southeastern
Wisconsin Regional Planning Commission were used to identify the affected receptors within
the distance to the toxic endpoint. Affected receptors are identified in Table 13 below:
Table 13
Affected Receptors
ALOHA Worst-Case Release Scenario
Public Receptors
Schools:
Residences:
Hospitals:
Prisons / Correctional Facilities:
Recreational Areas:
Deerfield Elementary School
Scanlon School
Lamberton School
254 Housing Units (638 occupants)
None
None
Other Recreational Area
Cliffside Park
On-Site Fishing Pier
Major Commercial Office Industrial
Facilities:
None
Other Public Receptors:
Recreational Users of Lake Michigan and
Shoreline
Environmental Receptors
National Parks, Forests, Monuments:
Designated Sanctuaries, Preserves,
Refuges:
Federal Wildness Areas:
Other Environmental Receptors:
None
None
None
Lake Michigan and Shoreline
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Affected Populations – Alternative-Case Release
Marplot Version 4.2.2 (current as of August 2012) mapping software was also used to
estimate the population impacts within the 0.22 mile distance to the toxic endpoint
concentration of 0.14 mg/L (200 ppm) of ammonia. A circle encompassing a 0.22 mile radius
from the center of the ammonia delivery trucks was superimposed on the Marplot map to
estimate populations that could be affected by an alternative-case release (See Appendix E).
Affected populations are based on data obtained from the U.S. Census Bureau and linked to
the mapping software program. Population data contained in the mapping system is based
on calendar year 2010 census data which represents the most current population estimates
available from the U.S. Census Bureau.
The "Census Blocks" method of calculation was used to estimate populations affected by the
alternative-case release scenario which is the only option available in Marplot 4.2.2 to
estimate populations affected.
As the census data does not contain information on
populations using Lake Michigan for recreational purposes (boaters and fishermen),
ChemReport developed a conservative estimate by assuming that 10 boats could potentially
be within a 0.22 mile radius of the OCPP facility with an average of five (5) persons per boat.
No individuals were accounted for on the OCPP on-site fishing pier during the time of the
release as the pier is outside of the 0.22 mile radius. A summary of all affected populations is
presented in Table 14 below.
Table 14
Affected Populations
ALOHA Alternative-Case Release Scenario
Alternative-Case Release Scenario
June 2011
Original Tank Farm
August 2012
Relocated Tank
Farm
Distance To Endpoint of 0.14 mg/l
0.21 miles
0.22 miles
Population Affected (2010 Census)
0
0
Population Affected (Lake Michigan Boaters)
50
50
Population Affected (Fishing Pier)
0
0
Total Population Affected
50
50
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13.1
ChemReport
Public Receptors – Alternative-Case Release
Marplot Version 4.2.2 (current as of August 2012) mapping software and public information
systems maintained by the United States Geological Survey, Racine and Milwaukee County
Schools, Wisconsin Historical Society, Wisconsin Register of Historical Places, National Park
Service Historical Landmark Survey, Racine and Milwaukee County Parks Systems,
Wisconsin Department of Corrections and aerial photographs provided by the Southeastern
Wisconsin Regional Planning Commission were used to identify the affected receptors within
the distance to the toxic endpoint. Affected receptors are identified In Table 15 below:
Table 15
Affected Receptors
ALOHA Alternative-Case Release Scenario
Public Receptors
Schools:
Residences:
Hospitals:
Prisons / Correctional Facilities:
Recreational Areas:
Major Commercial Office Industrial Facilities:
Other Public Receptors:
Environmental Receptors
National Parks, Forests, Monuments:
Designated Sanctuaries, Preserves, Refuges:
Federal Wildness Areas:
Other Environmental Receptors:
None
None
None
None
None
None
Recreational Users of Lake Michigan and
Shoreline
None
None
None
Lake Michigan and Shoreline
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14.0 RMP Registration
Under 40 CFR Part 68.36(b), the RMP is required to be updated within six (6) months after
completion of a revised or updated OCA if the updated OCA shows a two-fold increase or
decrease (doubled or halved) in the distance to a toxic endpoint. Table 16 below provides a
comparison and summary of the current OCA results versus previous modeling.
The distance to a toxic endpoint did not change by a two-fold increase or decrease.
Consequently, updating of the original RMP is not required based on the re-calculated
distance to a toxic endpoint.
Table 16
OCA Results
Comparison of Modeling Data
Worst-Case Scenario
June 2011
December 2011*
August 2012
Alternative-Case Scenario
Population
Toxic Distance
Population
Toxic Distance
1,163
1.5 miles
50
0.21 miles
528
0.91 miles
50
0.14 miles
1,163
1.5 miles
50
0.22 miles
* During use of temporary drop tanker for ammonia storage
However, under 40 CFR Part 68.190(b)(5), the RMP is required to be updated within six (6)
months of a change that requires a revised PHA or hazard review. As the relocated ammonia
storage tank farm required a revised hazard review, (conducted on July 9, 2012), an updated
RMP must be submitted to U.S. EPA within six (6) months of the hazard review date.
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15.0
ChemReport
Updated Hazard Review
A detailed Process Hazard Analysis (PHA) was originally performed November 17 and 18,
2010 using a combination of "What If" scenarios and a process safety checklist (See
ChemReport June 2011 RMP Plan) for the original SCR system.
The original PHA and safety checklist developed in 2010 continues to remain valid for the
components of the SCR system that were unaffected by the October 31, 2011 bluff failure.
The PHA also continues to remain valid for the ammonia storage tank farm since the
relocated tank farm was designed to original specifications reviewed during the 2010 PHA
and uses the same original equipment that was installed prior to the bluff failure.
A limited Hazard Review was conducted on July 9, 2012 with Jim Petersen and Dan Adams
of We Energies, and Michael Boozer and Sean Cranley of ChemReport. At that meeting, Mr.
Petersen explained that the newly constructed ammonia storage tank farm utilized the
original equipment that was installed prior to the October 2011 bluff failure and that all
procedures and process logic and controls remain valid at the permanent tank farm. The
following aspects of the permanent tank farm were discussed and reviewed:
1. As the same tanks that were installed prior to the bluff failure were being re-used,
there was no increase in the amount of ammonia stored onsite except that due to the
location of the new tank farm, additional piping to the SCR injection system had to be
installed. According to We Energies, this additional piping resulted in an additional
221 gallons of ammonia in the piping system. ChemReport accounted for this
additional volume in its Worst-Case release scenario.
2. Due to the location of the new tank farm, it was necessary to run a section of the
piping from the tank farm to the injection system underneath a local haul road. This
section of piping (approximately 25 feet) is installed inside of an underground
concrete trench that runs underneath the road. Should the pipe ever leak, the
released material would be contained and would drain back into the ammonia
storage tank farm dike. Additionally, it was necessary to run a section of the piping
inside one of the onsite buildings. However, no valves or drains were installed in the
piping run inside of the building so the potential for an indoor ammonia release was
determined to be virtually non-existent and should one occur, the facility’s emergency
response plan was adequate to address the release.
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3. The tank farm’s dike has a sump installed in the corner to be used to pump out any
released ammonia into a transport vehicle. Prior to the bluff failure, the old dike’s
sump had the potential to overflow into an adjacent pond. The pond was removed
after the bluff failure and no longer exists.
4. There exists a series of liquid above-ground storage tanks directly across from the
ammonia storage tank farm. However, these tanks contain process water, boiler
water and other inert liquid mixtures that would not adversely impact the ammonia
tank farm should a release occur.
5. The Washington Group conducted an exhaustive review of a previously performed
Geotechnical Engineering Report (prepared in 2007 by Wagner Komurka
Geotechnical Group) and determined that the location of the new ammonia storage
tank farm would not subject it to any future unexpected geological events such as the
one that occurred in October of 2011.
6. The Washington Group would ensure, through appropriate documentation, that the
relocated tanks are still suitable for service and that they were not subjected to nonvisual stresses during the bluff collapse that could precipitate or cause a future
release of ammonia from either tank.
7. Prior to filling the tanks with ammonia, We Energies will utilize the safety and hazard
review checklist developed for the original installation to ensure that all appropriate
hazard mitigation controls have been addressed. A copy of the checklist is contained
in Appendix F.
Subsequent to the July 9, 2012 meeting, We Energies provided ChemReport with additional
information indicating that the permanent tank farm dike was extended three (3) feet in
length adding an additional 500 cubic feet of containment to the system. ChemReport
accounted for this additional containment volume in its Worst-Case and Alternative Case
release scenarios modeling analyses.
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ChemReport
Prevention Program Elements
The following additional prevention program elements apply to the SCR aqueous ammonia
system as described in Table 17 below.
Table 17
Program Level 2 RMP Required Program Elements
Citation
§ 68.48
§ 68.50
§ 68.52
§ 68.54
§ 68.56
§ 68.58
§ 68.60
Section Title
Safety Information
Hazard Review
Operating Procedures
Training
Maintenance
Compliance Audits
Incident Investigation
The prevention program requirements for RMP Program Level 2 facilities from 40 CFR Part
68 are presented in the sub-sections that follow. All of the previously developed prevention
program elements remain valid as the construction and use of the new ammonia storage
tank farm uses the same original equipment and procedures that were in place prior to the
October 2011 bluff failure.
16.1
Management System
The OCPP facility has developed a management system to oversee the risk management
program to ensure that all of the risk management program elements are integrated and
implemented on an ongoing basis. All affected individuals at OCPP have been trained to
understand their respective lines of responsibility and communication.
The management system originally developed by OCPP has not changed. As a result, the
original management system structure provided in the June 2011 RMP program remains
valid and unchanged.
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16.2
ChemReport
Safety Information
The original safety information on the SCR system was developed jointly by Washington
Group, Riley Power, We Energies and OCPP personnel.
The process safety information for the ammonia storage tank farm and SCR system
originally developed by OCPP has not changed as the permanent ammonia storage tank
farm uses the same original equipment installed prior to the October 2011 bluff failure.
16.3
The
Operating Procedures
original
operating
procedures
for
the
entire
SCR
system
and
ammonia
storage/unloading processes were developed jointly by Washington Group, Riley Power, We
Energies and OCPP personnel. These procedures are separate from this document and are
not appended to this report. The procedures covered the following operations:

Normal operations

Emergency shutdown

Emergency operations

Normal shutdown

Start-up following a normal or emergency shutdown or a major change

Consequences of deviating

Steps to avoid, correct deviations

Equipment inspections

Maintenance
All of the above procedures remain valid as the new ammonia storage tank farm uses the
same original equipment installed prior to the October 2011 bluff failure.
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16.4
ChemReport
Training
OCPP has trained all SCR system employees in the operating and maintenance
procedures described above, and maintains documentation of all training activities.
All training programs previously developed remain valid as the new ammonia storage tank
farm uses the same original equipment installed prior to the October 2011 bluff failure and
the same operating procedures.
16.5
Maintenance
Maintenance procedures were previously developed by We Energies using a combination of
manufacturers’ or vendors’ recommendations as well as generally acceptable, good
engineering practices. Documentation of all preventative maintenance, inspection and testing
procedures are maintained at the facility. Maintenance employees have been trained in
these procedures. Additionally, a daily operator walk-down checklist has been developed by
We Energies so that all major system components are inspected on a daily basis.
All maintenance procedures remain valid as the new ammonia storage tank farm uses the
same original equipment installed prior to the October 2011 bluff failure.
16.6
Compliance Assessments
We Energies corporate environmental staff conduct the requisite compliance assessments of
each regulated We Energies facility at least once every three (3) years.
16.7
Incident Investigation
We Energies has in place a well-defined Incident Investigation procedure to ensure the
prompt investigation of all incidents. The Incident Investigation procedure remains valid as
the construction of the new ammonia storage tank did not change how incidents are
investigated.
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ChemReport
Community Emergency Response Plan
The Emergency Planning and Community Right-to-Know Act (EPCRA), was designed to
prevent or mitigate accidental releases of certain chemical substances. Section 302 of
EPCRA requires facilities possessing more than a specified threshold of a listed Extremely
Hazardous Substance (EHS) to participate in community wide emergency planning activities
that are directed by the local offices of emergency management.
Prior to 2001, aqueous ammonia solutions of greater than 20% were listed as an Extremely
Hazardous Substance under Section 302 with a threshold planning quantity of 500 pounds.
However, in 2001 U.S. EPA specifically exempted aqueous ammonia solutions (regardless
of concentration) from Section 302 planning requirements. Consequently, the OCPP facility
is not subject to Section 302 emergency planning as a result of its use of aqueous ammonia.
OCPP has coordinated its existing emergency response program with the Milwaukee County
and Racine County Offices of Emergency Management, Local Fire Departments, and other
applicable agencies. Although aqueous ammonia is not regulated under Section 302, its use
at the OCPP facility may be factored into the site-specific community emergency response
plan(s) developed by Milwaukee and Racine Counties and the facility will notify each agency,
including the Oak Creek Fire Department of the planned filling and use of the permanent
ammonia storage tanks prior to startup.
18.0
Facility Emergency Response Plan
The OCPP facility will implement its own Emergency Response Plan (ERP) that takes into
account facility-specific response actions which will be implemented in the event of an
emergency (e.g. chemical spill, weather, fire).
The chemical response provisions of the ERP provide basic response actions to be taken
such as emergency exit routes, evacuation areas, notification procedures, spill kit and
Personal Protective Equipment (PPE) locations, etc. Additional response activities are
contained in OCPP’s Spill Prevention, Control and Countermeasure (SPCC). The ERP is
maintained as a separate document to this RMP Plan.
The Emergency Response Plan remains valid as the construction and use of the new
ammonia storage tank will not change emergency response procedures.
OCPP OCA Update & Hazard Review – Ammonia Tank Farm Relocation
Page 31 of 32
Oak Creek Power Plant
OCA Update and Hazard Review
Ammonia Tank Farm Relocation
Final 09/24/2012
ChemReport
Questions concerning the contents of this revised OCA and Hazard Review should be
addressed to Mr. Dan Adams, Senior Environmental Consultant for We Energies at (414)
221-4674.
CHEMREPORT, INCORPORATED
_______________________________
Michael G. Boozer/CHMM
Certified Hazardous Materials Manager
Project Manager
187769-1
OCPP OCA Update & Hazard Review – Ammonia Tank Farm Relocation
Page 32 of 32