HomeMy WebLinkAboutNCS000158_FINAL PERMIT_20031120__ STORMWATER-DIVISION-CODINGTSHEET --
PERMIT NO.
Al LS (200 1 S�
DOC TYPE
9 FINAL PERMIT
❑ MONITORING INFO
❑ APPLICATION
❑ COMPLIANCE
❑ OTHER
DOC DATE
❑ 'A cul E l a b
YYYYM M DD
A TFRQ
Mr. William Travers
Cascade Die Casting
P.O. Box 8045
High Point, NC 27264
Dear Mr. Travers:
Michael F. Easley
Govemor
William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
�t3g Alan W. Klimek, P.E. Director
Division of Water Quality
October 17, 2003
Subject: Permit No. NCS000158
Cascade Die Casting I Atlantic
Guilford County
In response to your renewal application for continued coverage under NPDES stormwater permit NCS000158
the Division of Water Quality (Division) is forwarding herewith the subject state - NPDES permit. This permit is
issued pursuant to the requirements of North Carolina General Statute 143-215 .1 and the Memorandum of Agreemen
between North Carolina and the US Environmental Protection agency dated May 9, 1994 (or as subsequently
amended).
Please note that the Division has revised the analytical monitoring strategy for individual stormwater
permits. Based on a review of the permit monitoring data received to date, the analytical monitoring
measurement frequencies have been changed and cut-off concentrations have been removed. These changes
will be implemented for all second term individual stormwater permits with analytical monitoring requirements.
For those permits with analytical monitoring requirements, Part II - Monitoring, Controls, and Limiiations for
Permitted Discharges has been modified to reflect the change in monitoring strategy.
The qualitative monitoring strategy remains the same as the first term of the permit. Please note that the
semi-annual qualitative monitoring is a requirement of the permit. Failure to complete the monitoring as
required is a violation of the permit and any permit noncompliance constitutes a violation of the Clean Water
Act, Reference Part 111, Section A, Item 2 "Duty to Comply", Item 9 "Penalties for Tampering " and Item 10
"Penalties for Falsification of Reports" of your permit for further information.
If any parts, measurement frequencies or sampling requirements contained in this permit are
unacceptable to you, you have the right to an adjudicatory hearing upon written request within thirty (30) days
following receipt of this letter. This request must be in the form of a written petition, conforming to Chapter
150B of the North Carolina General Statutes, and filed with the Office of Administrative Hearings, Post Office
Drawer 27447, Raleigh, North Carolina 27611 -7447. Unless such demand is made, this decision shall be final
and binding.
Please take notice this permit is not transferable. Part III, B2. addresses the requirements to be followed
in case of change in ownership or control of this discharge.
This permit does not affect the legal requirements to obtain other permits which may be required by the
Division of Water Quality or permits required by the Division of Land Resources, Coastal Area Management
Act or any other Federal or Local governmental permit that may be required.
A"A
NCDENR
Customer Service Division of Water Quality 1617 Mail Service Center Raleigh, NC 27699-1617 (919) 733-7015
1 800 623-7748
Mr. William Travers
Page 2
October 17, 2003
If you have any questions concerning this permit, please contact Aisha Lau at telephone number
(919)733-5083 ext. 578.
Sincerely,
ORIGINAL SIGNED BY
WILLIAM G. MILLS
for Alan W. Klimek
cc: Mr. Roger O. Pfaff, EPA
Winston=Salem Regional Office
Stormwater and General Permits Unit
Central Files
0
NCS000158
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
PERMIT
TO DISCHARGE STORMWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
In compliance with the provisions of North Carolina General Statute 143-215.1, other lawful
standards and regulations promulgated and adopted by the North Carolina Environmental
Management Commission, and the Federal Water Pollution Control Act, as amended,
Cascade Die Casting / Atlantic
is hereby authorized to discharge stormwater from a facility located at
1800 Albertson Road
High Point, NC
Guilford County
to receiving waters designated as an unnamed tributary to Kennedy Mill Creek, a class C stream,
in the Yadkin -Pee Dee River Basin in accordance with the discharge limitations, monitoring
requirements, and other conditions set forth in Parts 1, II, III, IV, V and VI hereof.
This permit shall become effective November 1, 2003.
This permit and the authorization to discharge shall expire at midnight on October 31, 2008.
Signed this day October 17, 2003.
ORIGINAL SIGNED BY
WILLIAM C. MILLS
for Alan W. Klimek, P.E., Director
Division of Water Quality
By the Authority of the Environmental Management Commission
Permit No. NCS000158
4. Individual Permit Modification, Revocation and Reissuance, or
Termination
5. Permit Actions
Section C: Operation and Maintenance of Pollution Controls
1. Proper Operation and Maintenance
2. Need to Halt or Reduce Not a Defense
3. Bypassing of Stormwater Control Facilities
Section D: Monitoring and Records
1.
Representative Sampling
2.
Recording Results
3.
Flow Measurements
4.
Test Procedures
5.
Representative Outfall
6.
Records Retention
7.
Inspection and Entry
Section E: Reporting Requirements
1. Discharge Monitoring Reports
2. Submitting Reports
3. Availability of Reports
4. Non-Stormwater Discharges
5. Planned Changes
6. Anticipated Noncompliance
7. Bypass
8. Twenty-four Hour Reporting
9. Other Noncompliance
10. Other Information ,
PART IV LIMITATIONS REOPENER
PART V ADMINISTERING AND COMPLIANCE MONITORING FEE
REQUIREMENTS
PART VI DEFINITIONS
III
'V
Permit No. NCS000158
SECTION C: LOCATION MAP
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Part I Page 2 of 2
Permit No. NCS000158
nonstructural measures. The stormwater management plan, at a minimum, shall
incorporate the following:
(a) Feasibility Study. A review of the technical and economic feasibility of changing
the methods of operations and/or storage practices to eliminate or reduce exposure
of materials and processes to stormwater. Wherever practical, the permittee shall
prevent exposure of all storage areas, material handling operations, and
manufacturing or fueling operations. In areas where elimination of exposure is
not practical, the stormwater management plan shall document the feasibility of
diverting the stormwater runoff away from areas of potential contamination.
(b) Secondary Containment Schedule. A schedule to provide secondary containment
for bulk storage of liquid materials, storage of Section 313 of Title III of the
Superfund Amendments and Reauthorization Act (SARA) water priority
chemicals, or storage of hazardous substances to prevent leaks and spills from
contaminating stormwater runoff. If the secondary containment devices are
connected directly to stormwater conveyance systems, the connection shall be
controlled by manually activated valves or other similar devices [which shall be
secured with a locking mechanism] and any stormwater that accumulates in the
containment area shall be at a minimum visually observed for color, foam, outfall
staining, visible sheens and dry weather flow, prior to release of the accumulated
stormwater. Accumulated stormwater shall be released if found to be
uncontaminated by the material stored within the containment area. Records
documenting the individual making the observation, the description of the
accumulated stormwater and the date and time of the release shall be kept for a
period of five .years.
(c) BMP Summary. A narrative description shall be provided of Best Management
Practices (BMPs) to be considered such as, but not limited to, oil and grease
separation, debris control, vegetative filter strips, infiltration and stormwater
detention or retention, where necessary. The need for structural BMPs shall be
based on the assessment of potential of sources to contribute significant quantities
of pollutants to stormwater discharges and data collected through monitoring of
stormwater discharges.
3. Spill Prevention and Response Plan. The Spill Prevention and Response Plan (SPRP)
shall incorporate an assessment of potential pollutant sources based on a materials
inventory of the facility. Facility personnel (or team) responsible for implementing the
SPRP shall be identified. A responsible person shall be on -site at all times during facility
operations that have the potential to contaminate stormwater runoff through spills or
exposure of materials associated with the facility operations. The SPRP must be site
stormwater specific. Therefore, a SPCC plan may be a component of the SPRP, but may
not be sufficient to completely address the stormwater aspects of the SPRP. The common
elements of the SPCC with the SPRP may be incorporated by reference into the SPRP.
4. Preventative Maintenance and Good Housekeeping Program. A preventative
maintenance program shall be developed. The program shall document schedules of
inspections and maintenance activities of stormwater control systems, plant equipment
Part II Page 2 of 5
I"
Permit No. NCS00015 $
SECTION B: QUALITATIVE MONITORING REQUIREMENTS
Qualitative monitoring requires a visual inspection of each stormwater outfall regardless of
representative outfall status and shall be performed as specified below in Table 1. Qualitative
monitoring is for the purpose of evaluating the effectiveness of the Stormwater Pollution
Prevention Plan (SPPP) and assessing new sources of stormwater pollution. No analytical tests
are required. Qualitative monitoring of stormwater outfalls does not need to be performed during
a representative storm event.
In the event an atypical condition is noted at a stormwater discharge outfall, the Permittee shall
document the suspected cause of the condition and any actions taken in response to the
discovery. This documentation will be maintained with the Stormwater Pollution Prevention
Plan.
All qualitative monitoring will be performed twice per year, once in the spring (April - June) and
once in the fall (September - November).
Table 1. Qualitative Monitoring Requirements
Iha51 >�kC etertis
NORx
= equeri
.� aBCIOri
li�Iantiit
Color
Semi -Annual
SDO
Odor
Semi -Annual
SDO
Clarity
Semi -Annual
SDO
Floating Solids
Semi -Annual
SDO
Suspended Solids
Semi -Annual
SDO
Foam
Semi -Annual
SDO
Oil Sheen
Semi -Annual
SDO
Other obvious indicators
of stormwater pollution
Semi -Annual
SDO
Footnotes:
1 Monitoring Location: Qualitative monitoring shall be performed at each stormwater discharge outfall (SDO)
regardless of representative outfall status.
SECTION C: ON -SITE VEHICLE MAINTENANCE MONITORING REQUIREMENTS
Facilities which have any vehicle maintenance activity occurring on -site which uses more than
55 gallons of new motor oil per month when averaged over the calendar year shall perform
analytical monitoring as specified below in Table 2. This monitoring shall be performed at all
outfalls which discharge stormwater runoff from vehicle maintenance areas.
All analytical monitoring shall be performed during a representative storm event. The required
monitoring will result in a minimum of 4 analytical samplings being conducted over the term of
Part II Page 4 of 5
Permit No. NCS000158
PART III STANDARD CONDITIONS FOR NPDES STORMWATER INDIVIDUAL PERMITS
SECTION A: COMPLIANCE AND LIABILITY
Compliance Schedule
The permittee shall comply with Limitations and Controls specified for stormwater discharges in
accordance with the following schedule:
Existing Facilities: The Stormwater Pollution Prevention Plan shall be developed and implemented within
12 months of the effective date of the initial permit and updated thereafter on an annual basis. Secondary
containment, as specified in Part II, Section A, Paragraph 2(b) of this permit, shall be accomplished within
12 months of the effective date of the initial permit issuance.
Proposed Facilities: The Stormwater Pollution Prevention Plan shall be developed and implemented prior to
the beginning of discharges from the operation of the industrial activity and be updated thereafter on an
annual basis. Secondary containment, as specified in Part II, Section A, Paragraph 2(b) of this permit shall
be accomplished prior to the beginning of discharges from the operation of the industrial activity.
2. Duty to Comply_
The permittee must comply with all conditions of this individual permit. Any permit noncompliance
constitutes a violation of the Clean Water Act and is grounds for enforcement action; for permit
termination, revocation and reissuance, or modification; or denial of a permit upon renewal application.
a. The permittee shall comply with standards or prohibitions established under section 307(a) of the
Clean Water Act for toxic pollutants within the time provided in the regulations that establish these
standards or prohibitions, even if the permit has not yet been modified to incorporate the
requirement.
b. The Clean Water Act provides that any person who violates a permit condition is subject to a civil
penalty not to exceed $27,500 per day for each violation. Any person who negligently violates any
permit condition is subject to criminal penalties of $2,500 to $25,000 per day of violation, or
imprisonment for not more than 1 year, or both. Any person who knowingly violates permit
conditions is subject to criminal penalties of $5,000 to $50,000 per day of violation, or
imprisonment for not more than 3 years, or both. Also, any person who violates a permit condition
may be assessed an administrative penalty not to exceed $11,000 per violation with the maximum
amount not to exceed $137,500. [Ref: Section 309 of the Federal Act 33 USC 1319 and 40 CFR
122.41(a).]
c. Under state law, a daily civil penalty of not more than twenty-five thousand dollars ($25,000) per
violation may be assessed against any person who violates or fails to act in accordance with the
terms, conditions, or requirements of a permit. [Ref: North Carolina General Statutes 143-
215.6A]
d. Any person may be assessed an administrative penalty by the Director for violating section 301,
302, 306, 307, 308, 318, or 405 of the Act, or any permit condition or limitation implementing any
of such sections in a permit issued under section 402 of the Act. Administrative penalties for Class
I violations are not to exceed $11,000 per violation, with the maximum amount of any Class I
penalty assessed not to exceed $27,500. Penalties for Class II violations are not to exceed $11,000
per day for each day during which the violation continues, with the maximum amount of any Class
II penalty not to exceed $137,500.
Part III Page 1 of 8 Pages
y
Permit No. NCS000158
permit, including monitoring reports or reports of compliance or noncompliance shall, upon conviction, be
punished by a fine of not more than $10,000 per violation, or by imprisonment for not more than two years
per violation, or by both.
SECTION 8: GENERAL CONDITIONS
Individual_ Permit Expiration
The permittee is not authorized to discharge after the expiration date. In order to receive automatic
authorization to discharge beyond the expiration date, the permittee shall submit forms and fees as are
required by the agency authorized to issue permits no later than 180 days prior to the expiration date. Any
permittee that has not requested renewal at least 180 days prior to expiration, or any permittee that does not
have a permit after the expiration and has not requested renewal at least 180 days prior to expiration, will be
subjected to enforcement procedures as provided in NCGS § 143-2153.6 and 33 USC 1251 et. seq.
2. Transfers
This permit is not transferable to any person except after notice to and approval by the Director. The
Director may require modification or revocation and reissuance of the permit to change the name and
incorporate such other requirements as may be necessary under the Clean Water Act. Permittee is required
to notify the Division in writing in the event the permitted facility is sold or closed.
3. Signatory RqQuirements
All applications, reports, or information submitted to the Director shall be signed and certified.
a. All applications to be covered under this individual permit shall be signed as follows:
(1) For a corporation: by a responsible corporate officer. For the purpose of this Section, a
responsible corporate officer means: (a) a president, secretary, treasurer or vice president
of the corporation in charge of a principal business function, or any other person who
performs similar policy or decision making functions for the corporation, or (b) the
manager of one or more manufacturing production or operating facilities employing more
than 250 persons or having gross annual sales or expenditures exceeding 25 million (in
second quarter 1980 dollars), if authority to sign documents has been assigned or
delegated to the manager in accordance with corporate procedures.
(2) For a partnership or sole proprietorship: by a general partner or the proprietor,
respectively; or
(3) For a municipality, State, Federal, or other public agency: by either a principal executive
officer or ranking elected official.
b. All reports required by the individual permit and other information requested by the Director shall
be signed by a person described above or by a duly authorized representative of that person. A
person is a duly authorized representative only if:
(1) The authorization is made in writing by a person described above;
(2) The authorization specified either an individual or a position having responsibility for the
overall operation of the regulated facility or activity, such as the position of plant
manager, operator of a well or well field, superintendent, a position of equivalent
responsibility, or an individual or position having overall responsibility for environmental
Part III Page 3 of 8 Pages
Permit No. NCS000158
weather. This condition is not satisfied if adequate backup controls should have been installed in
the exercise of reasonable engineering judgment to prevent a bypass which occurred during normal
periods of equipment downtime or preventive maintenance; and
C. The permittee submitted notices as required under, Part III, Section E of this permit.
If the Director determines that it will meet the three conditions listed above, the Director may approve an
anticipated bypass after considering its adverse effects.
SECTION D: MONITORING AND RECORDS
1. Representative Sampfing
Samples collected and measurements taken, as required herein, shall be characteristic of the volume and
nature of the permitted discharge. Analytical sampling shall be performed during a representative storm
event. Samples shall be taken on a day and time that is characteristic of the discharge. All samples shall be
taken before the discharge joins or is diluted by any other waste stream, body of water, or substance.
Monitoring points as specified in this permit shall not be changed without notification to and approval of
the Director.
2. Recording Results
For each measurement, sample, inspection or maintenance activity performed or collected pursuant to the
requirements of this individual permit, the permittee shall record the following information:
a. The date, exact place, and time of sampling, measurements, inspection or maintenance activity;
b. The individual(s) who performed the sampling, measurements, inspection or maintenance activity;
C. The date(s) analyses were performed;
d. The individual(s) who performed the analyses,
e. The analytical techniques or methods used; and
f. The results of such analyses.
3. Flow Measurements
Where required, appropriate flow measurement devices and methods consistent with accepted scientific
practices shall be selected and used to ensure the accuracy and reliability of measurements of the volume of
monitored discharges.
4. Test Procedures
Test procedures for the analysis of pollutants shall conform to the EMC regulations published pursuant to
NCGS 143-215.63 et. seq, the Water and Air Quality Reporting Acts, and to regulations published pursuant
to Section 304(g), 33 USC 1314, of the Federal Water Pollution Control Act, as Amended, and Regulation
40 CFR 136.
To meet the intent of the monitoring required by this individual permit, all test procedures must produce
minimum detection and reporting levels and all data generated must be reported down to the minimum
detection or lower reporting level of the procedure.
Part III Page 5 of 8 Pages
Permit No. NCS000158
Availability of Reports
Except for data determined to be confidential under NCGS 143-215.3(a)(2) or Section 308 of the Federal
Act, 33 USC 1318, all reports prepared in accordance with the terms shall be available for public inspection
at the offices of the Division of Water Quality. As required by the Act, analytical data shall not be
considered confidential. Knowingly making any false statement on any such report may result in the
imposition of criminal penalties as provided for in NCGS 143-215.613 or in Section 309 of the Federal Act.
4. Non-Stormwater Discharges
If the storm event monitored in accordance with this individual permit coincides with a non-stormwater
discharge, the permittee shall separately monitor all parameters as required under the non-stormwater
discharge permit and provide this information with the stormwater discharge monitoring report
5.. Planned Changes
The permittee shall give notice to the Director as soon as possible of any planned changes at the permitted
facility which could significantly alter the nature or quantity of pollutants discharged. This notification
requirement includes pollutants which are not specifically listed in the individual permit or subject to
notification requirements under 40 CFR Part 122.42 (a).
6. Anticipated Noncompliance
The permittee shall give notice to the Director as soon as possible of any planned changes at the permitted
facility which may result in noncompliance with the individual permit requirements.
7. Bypass
a. Anticipated bypass. If the permittee knows in advance of the need for a bypass, it shall submit
prior notice, if possible at least ten days before the date of the bypass; including an evaluation of
the anticipated quality and affect of the bypass.
b. Unanticipated bypass. The permittee shall submit notice within 24 hours of becoming aware of an
unanticipated bypass.
8. Twenty-four How Reporting
The permittee shall report to the central office or the appropriate regional office any noncompliance which
may endanger health or the environment. Any information shall be provided orally within 24 hours from
the time the permittee became aware of the circumstances. A written submission shall also be provided
within 5 days of the time the permittee becomes aware of the circumstances.
The written submission shall contain a description of the noncompliance, and its causes; the period of
noncompliance, including exact dates and times, and if the noncompliance has not been corrected, the
anticipated time compliance is expected to continue; and steps taken or planned to reduce, eliminate, and
prevent reoccurrence of the noncompliance.
The Director may waive the written report on a case -by -case basis if the oral report has been received
within 24 hours.
Other Noncompliance
The permittee shall report all instances of noncompliance not reported under 24 hour reporting at the time
monitoring reports are submitted.
Part III Page 7 of 8 Pages
Permit No. NCS000158
PART IV LIMITATIONS REOPENER
This individual permit shall be modified or alternatively, revoked and reissued, to comply with any applicable
effluent guideline or water quality standard issued or approved under Sections 302(b) (2) (c), and (d), 304(b) (2) and
307(a) of the Clean Water Act, if the effluent guideline or water quality standard so issued or approved:
a. Contains different conditions or is otherwise more stringent than any effluent limitation in the individual
permit; or
b. Controls any pollutant not limited in the individual permit.
The individual permit as modified or reissued under this paragraph shall also contain any other requirements in the
Act then applicable.
PART V ADMINISTERING AND COMPLIANCE MONITORING FEE
REQUIREMENTS
The permittee must pay the administering and compliance monitoring fee within 30 (thirty) days after being billed by
the Division. Failure to pay the fee in timely manner in accordance with 15A NCAC 2H .0105(b)(4) may cause this
Division to initiate action to revoke the Individual Permit.
PART VI DEFINITIONS
Act
See Clean Water Act,
2. Arithmetic Mean
The arithmetic mean of any set of values is the summation of the individual values divided by the number of
individual values.
3. Allowable Non-Soormwater Discharges
This permit regulates stormwater discharges. Non-stormwater discharges which shall be allowed in the
stormwater conveyance system are:
(a) All other discharges that are authorized by a non-stormwater NPDES permit.
(b) Uncontaminated groundwater, foundation drains, air -conditioner condensate without added
chemicals, springs, discharges of uncontaminated potable water, waterline and fire hydrant
flushings, water from footing drains, flows from riparian habitats and wetlands.
(c) Discharges resulting from fire -fighting or fire -fighting training.
4. Best Management Practices (BMPs}
Measures or practices used to reduce the amount of pollution entering surface waters. BMPs may take the
form of a process, activity, or physical structure.
Parts IV, V and VI Page I of 5
Permit No. NCS000158
16. Permittee
The owner or operator issued a permit pursuant to this individual permit.
17. Point Source Discharge of Stormwater
Any discernible, confined and discrete conveyance including, but not specifically limited to, any pipe, ditch,
channel, tunnel, conduit, well, or discrete fissure from which stormwater is or may be discharged to waters
of the state.
18. Representative Storm Event
A storm event that measures greater than 0.1 inches of rainfall and that is preceded by at least 72 hours in which no
storm event measuring greater than 0.1 inches has occurred. A single storm event may contain up to 10 consecutive
hours of no precipitation. For example, if it rains for 2 hours without producing any collectable discharge, and then
stops, a sample may be collected if a rain producing a discharge begins again within the next 10 hours.
19. Representative Outfall Status
When it is established that the discharge of stormwater runoff from a single outfall is representative of the
discharges at multiple outfalls, the DWQ may grant representative outfall status. Representative outfall
status allows the permittee to perform analytical monitoring at a reduced number of outfalls.
20. Rinse Water Discharge
The discharge of rinse water from equipment cleaning areas associated with industrial activity. Rinse
waters from vehicle and equipment cleaning areas are process wastewaters and do not include washwaters
utilizing any type of detergent or cleaning agent.
21. Secondary Containment
Spill containment for the contents of the single largest tank within the containment structure plus sufficient
freeboard to allow for the 25-year, 24-hour storm event.
22. Section 313 Water Priority Chemical
A chemical or chemical category which:
a. Is listed in 40 CFR 372.65 pursuant to Section 313 of Title III of the Superfund Amendments and
Reauthorization Act (SARA) of 1986, also titled the Emergency Planning and Community Right -
to -Know Act of 1986;
Is present at or above threshold levels at a facility subject to SARA title III, Section 313 reporting
requirements; and
C. That meet at least one of the following criteria:
(1) Is listed in Appendix D of 40 CFR part 122 on either Table II (organic priority
pollutants), Table III (certain metals, cyanides, and phenols) or Table IV (certain toxic
pollutants and hazardous substances);
(2) Is listed as a hazardous substance pursuant to section 311(b)(2)(A) of the CWA at 40
CFR 116.4; or
(3) Is a pollutant for which EPA has published acute or chronic water quality criteria.
Part VI Page 3 of 5 Pages
Permit No. NCS000158
32. Upset
Means an exceptional incident in which there is unintentional and temporary noncompliance with
technology based permit effluent limitations because of factors beyond the reasonable control of the
permittee. An upset does not include noncompliance to the extent caused by operational error, improperly
designed treatment or control facilities, inadequate treatment or control facilities, lack of preventive
maintenance, or careless or improper operation.
33. Vehicle Maintenance Activity
Vehicle rehabilitation, mechanical repairs, painting, fueling, lubrication, vehicle cleaning operations, or
airport deicing operations.
34. Visible Sedimentation
Solid particulate matter, both mineral and organic, that has been or is being transported by water, air,
gravity, or ice from its site of origin which can be seen with the unaided eye.
35. 25-year, 24 hour storm event
The maximum 24-hour precipitation event expected to be equaled or exceeded, on the average, once in 25
years.
Part VI Page 5 of 5 Pages