D3 - IDDE Investigations Guidelines-April 2022

CITY OF
DURHAM
DESCRIPTION, GUIDELINES, AND PROCEDURES FOR ILLICIT
DISCHARGE DETECTION AND ELIMINATION (IDDE)
Reviewed by:
INVESTIGATIONS
City of Durham - Department of Public Works
Stormwater & GIS Services Division
Water Quality Unit
Date:
Michelle Woolfolk, Water Quality Manager
City of Durham Stormwater & GIS Services—[phone]
www.DurhamNC.gov/stormwater
Design/Plan Review—Drainage/Flooding Concerns—Floodplain Information
Stormwater Public Education —Surface Water Quality—Stormwater Billing—GIS Mapping

Preface
This document contains a description of the IDDE investigations program, in addition to
guidelines procedures for City of Durham staff conducting water quality investigations. This
document is part of a series of guidelines and procedures covering implementation of the City's
illicit discharge detection and elimination (IDDE) program.
List of Common Initialisms and Acronyms
ANSI —American National Standards Institute
GIS —Geographic Information System
GIPS —Global Positioning System
IDDE — Illicit Discharge Detection and Elimination
MS4 — Municipal Separate Storm Sewer System
NOR —Notice of Requirement
NOV — Notice of Violation
NPDES— National Pollutant Discharge Elimination System
OSHA — Occupational Safety & Health Administration
WQ— Water Quality

Table of Contents
Preface........................................................................................................................................................... i
List of Common Initialisms and Acronyms.....................................................................................................
i
Purpose.........................................................................................................................................................4
Background...................................................................................................................................................4
Introduction to Illicit Discharges...................................................................................................................4
CommonIllicit Discharges.........................................................................................................................5
Water Quality Investigations Authority........................................................................................................6
Evaluating Pollution Complaints...............................................................................................................6
Enforcement and Jurisdiction Exceptions.................................................................................................7
Matters Enforced by Other Departments and Agencies..........................................................................
7
Discharges from industrial activities allowed by NPDES Stormwater Permit...........................................7
Allowable wastewater discharges............................................................................................................7
Authorized non-stormwater discharges...................................................................................................8
Sources of Pollution Complaints.................................................................................................................10
PublicReporting Methods......................................................................................................................10
WQ Staff -Initiated Investigations............................................................................................................10
FieldObservations..................................................................................................................................11
StreamMonitoring..................................................................................................................................11
Dry Weather Outfall Screening...............................................................................................................11
SafetyOverview..........................................................................................................................................11
Personal Protective Equipment..............................................................................................................11
Injury Response and Reporting...............................................................................................................12
SafetyAssessment..................................................................................................................................12
Hazardous Materials and Conditions......................................................................................................12
HostileIndividuals...................................................................................................................................12
RoadwayHazards....................................................................................................................................13
OtherHazards.........................................................................................................................................13
ConfinedSpaces......................................................................................................................................13
InvestigationProcedures............................................................................................................................14
General Procedure Overview..................................................................................................................14
It]

Collection and Control of Evidence.........................................................................................................15
Investigation Preparation.......................................................................................................................15
Information to Collect from Complainants.............................................................................................15
Jurisdiction..............................................................................................................................................15
Equipmentand Supplies.........................................................................................................................15
Entryonto Premises................................................................................................................................15
Evidence of a violation in plain view.......................................................................................................16
Consent to enter premises......................................................................................................................17
Investigation Best Practices....................................................................................................................17
Photographsand Videos.........................................................................................................................18
SourceTracking.......................................................................................................................................18
GISMap Resources.................................................................................................................................18
TracingDye Tests....................................................................................................................................19
FieldMeters and Test Kits.......................................................................................................................20
Water Samples for Laboratory Analysis..................................................................................................20
VideoPipe Inspection.............................................................................................................................20
Sanitary Sewage Related Investigations.................................................................................................
20
Illicit Vehicle Washing Operations Investigations...................................................................................21
Identifying and Contacting Responsible Parties.....................................................................................22
BusinessInformation..............................................................................................................................23
ParcelOwnership....................................................................................................................................
23
InvestigationFollow-ups.........................................................................................................................23
CodeEnforcement..................................................................................................................................
24
SpillReporting.............................................................................................................................................24
Reporting Major Spills to State Regulators, Generally...........................................................................24
Reporting City or County Sewer Spills to the System Operator.............................................................
24
Reporting Private Sanitary Sewer Spills to State Regulators..................................................................25
Reporting Spills of Hazardous Substances to State Regulators..............................................................25
Reporting Petroleum Spills to State Regulators......................................................................................25
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Purpose
The guidelines and procedures in this document will enable a Water Quality staff member to investigate
surface water pollution reports and collect evidence in a manner that preserves individual rights,
promotes accuracy and consistency, and provides documentation to support enforcement actions.
Background
The City of Durham was issued an NPDES municipal stormwater permit (NCS000249) by the State Dept.
of Environmental Quality (DEQ). One requirement of this permit is that the City implement a program to
identify and eliminate non-stormwater discharges from its MS4.
The Water Quality Unit of the Stormwater & GIS Services Division has been conducting water quality
investigations since 1997. The Unit has developed resources critical for supporting illicit discharge
identification and tracking, including stream monitoring programs and digital GIS maps of water, sewer,
and stormwater systems. Our Outreach and Education programs have also increased public
understanding of the impacts of illicit discharges while advertising reporting mechanisms for pollution
concerns.
Eliminating illicit discharges is a cost-effective means of restoring and protecting surface water quality.
Investigations are an essential component of a comprehensive illicit discharge control program.
Investigations rely on an educated public to identify possible pollution sources for investigation by staff.
They also provide an opportunity for staff to interact with and further educate the public about adverse
impacts of illicit discharges and illicit connections on water quality. Increased public awareness of illicit
discharges results in more effective reporting by the public, aiding the City's efforts to protect water
quality. Once an investigation identifies a violation, a combination of education and enforcement is used
to eliminate sources and to remediate discharges.
Introduction to Illicit Discharges
Stormwater Quality's slogan, "Only Rain in the Drain" promotes the general rule that any substance not
entirely composed of rainwater ("non-stormwater") may not be put into the storm drainage system.
Generally, an "illicit discharge" is a non-stormwater discharge into the storm drainage system. It is
important to understand that no illicit discharge occurs unless and until the substance actually enters
the drainage system.
According to City Code § 70-493, the "drainage system" is defined as:
...the system of natural and constructed conveyances for collecting and transporting
stormwater, whether publicly or privately owned. It includes lakes, ponds, rivers, perennial and
intermittent streams, connected wetlands, open ditches, catch basins and other inlets, pipes,
sewers, drains, culverts, and, in addition, created stormwater management facilities that
provide partial treatment by passive means such as wet detention ponds, detention basins, and
stormwater wetlands. The MS4 and waters of the state within the city are components included
within the drainage system, among other components.
4

The general rule prohibiting illicit discharges is found in City Code, § 70-511(a):
Prohibition. The discharge, emission, disposal, pouring, or pumping, directly or indirectly, to the
drainage system of any liquid, solid, gas, or other substance, other than stormwater, is an illicit
discharge and is prohibited, except as allowed in section 70-513. This prohibition also includes
airborne emissions where such emissions deposit pollutants into the drainage system.
Illicit discharges can be either direct or indirect. § 70-511(a) includes discharges "directly or indirectly." A
direct illicit discharge is one where the non-stormwater substance is dumped, poured, pumped, or
otherwise aimed toward and flows into the drainage system by its own force. An indirect illicit discharge
is one where the substance was deposited in an area where rainwater or snowmelt carried it into the
drainage system.
Examples:
• Direct discharge
o There is a business washing cars in a parking lot. The dirty water from the cars runs off
the pavement and into a nearby storm drain.
o A homeowner rakes leaves from their lawn into a storm drain.
o A bag of fertilizer tears open on a homeowner's driveway. The homeowner uses a hose
to wash the fertilizer into the nearby storm drain.
• Indirect discharge
o There is a business washing cars in a parking lot. The workers use a vacuum to clean car
interiors. At the end of the day, they scatter the vacuum contents on the parking lot far
from any storm drains. During the night, a rain storm washes the vacuum contents into
the storm drain.
o A homeowner rakes leaves from their yard into a pile on the edge of her property. The
next morning, a rain storm blows and washes those leaves into the street, where they
are carried into the storm drain.
o Oil leaks from a resident's car parked on the street. The resident does not clean up the
puddle of leaked oil. It rains before they clean it up. Stormwater runoff carries the oil to
the storm drain.
Common Illicit Discharges
Some of the most common illicit discharges encountered by the Water Quality Unit include:
• Sewage sources
o Overflows and leaks from municipal sanitary systems
o Overflows and leaks from private sanitary systems
• Automotive sources
o Mobile car wash wastewaters
o Improper motor oil disposal
o Fluid leaks from vehicle accidents
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• Yard waste (leaves and clippings)
• Painting wastewaters from cleaning equipment
• Soil erosion from construction sites with insufficient control measures
• Trash dumping
• Greywater discharges from improperly plumbed sinks and laundry appliances
• Concrete truck and equipment wash water
• Cooking grease and cleaning wastewater from food service
• Outdoor surface washing activities without proper containment and disposal
Water Quality Investigations Authority
Water Quality is authorized to investigate and enforce non-stormwater discharges to the drainage
system, surface waters, or both.
According to City Code §1-12, WQ only has authority to investigate matters within the City limits or
matters that are on the border and are impacting the City's drainage system or surface waters within
the City limits.
Though there may be overlaps, WQ does not directly regulate safety, waste management, groundwater,
land quality, air quality, wildlife, or other non-stormwater matters. Where WQ is involved in a matter
with multiple types of environmental impacts, WQ only has authority over the stormwater, drainage
system, and surface waters components.
Evaluating Pollution Complaints
To be investigable, a complaint must allege sufficient facts to implicate the drainage system, surface
waters, or both. Complaints that lack necessary details cannot be effectively investigated. Examples of
such necessary facts are:
• A location precise enough to direct our efforts efficiently
• There must be a discernable pollution issue via:
o Sensory description (odor, color, other unusual phenomena)
o Personal knowledge of a specific incident leading to a discharge (such as an eyewitness
to a fuel tank rupture)
o Photographic or video evidence submission that clearly shows the nature of the issue
If the complaint fails to furnish sufficient information, the investigator should attempt to contact the
complainant to gather more facts. This may lead to an investigable complaint. If sufficient additional
facts cannot be gathered, no investigation is conducted.
L

Enforcement and Jurisdiction Exceptions
Matters Enforced by Other Departments and Agencies
Certain complaints may implicate the drainage system, surface water, or both, but not fall under
investigations authority. The following are exceptions to investigable complaints:
• Construction Sites
o Sites with disturbed areas greater than 12,000 square feet are managed by Durham
County Erosion and Sediment Control.
o Sites with disturbed areas greater than 1 acre have State -issued NPDES stormwater
permits. Issues at these sites should be forwarded to the NC Division of Water
Resources Surface Water Protection (Raleigh Regional Office).
o Sites developed with public funding are also regulated by the State. Forward issues to
the Raleigh Regional Office (as above).
• Trash and other debris
o Nuisance and appearance issues at residential use properties are handled by the
Neighborhood Improvement Services Department.
o Construction debris matters are handled by Zoning Enforcement in the Durham
City/County Planning Department
• Stream Buffer Issues
o These matters are handled by the Durham City -County Planning Department.
Discharges from industrial activities allowed by NPDES Stormwater Permit
If a facility is covered by a NPDES General or Individual Stormwater Permit, then the permit authorizes
non-stormwater discharges associated with the industrial activity, provided that the facility is in
compliance with all of the requirements and conditions in the permit. The term "associated with the
industrial activity" means directly related to manufacturing, processing, or raw material storage areas at
an industrial site. Permitted discharges that are in compliance with permit conditions are allowable
under State law and are not illicit discharges under the City of Durham's ordinance.
Additional information pertinent to industrial facility inspections and NPDES industrial permits may be
found in the Water Quality document Stormwater Inspections Program Guidance and Procedures.
When a WQ investigation involves an industrial or suspected industrial activity, the investigator should
search for a description of the facility in the Inspections Database and/or discuss with a member of the
inspections team. The facility may need to be included in the inspection program or elevated in priority
if already part of it.
Allowable wastewater discharges
The following NPDES-permitted wastewater discharges are conditionally authorized:
• Non -contact cooling water, boiler blow -down, cooling tower, condensate, hydroelectric dams

• Groundwater Remediation (petroleum)
• Sand Dredging
• Fish & Seafood-Packing/Rinsing/Fish Farms
• Treated domestic wastewater from single family residences
• Pesticide application according to state and federal rules
• Irrigation or storage of reclaimed water
Authorized non-stormwater discharges
Municipal Separate Storm Sewer System
The City's Municipal NPDES Stormwater Permit (NCS000249) authorizes the discharge of stormwater
from the City's Municipal Separate Storm Sewer System (MS4). This permit also authorizes a limited
number non-stormwater discharges through the MS4, provided that they are not found to be significant
contributors of pollutants.
These authorized discharges are also listed in City Code §70-513(5):
• De -chlorinated water line flushing
• Landscape irrigation
• Diverted stream flows
• Rising ground waters
• Uncontaminated ground water infiltration
• Uncontaminated pumped ground water
• Discharges from potable water sources
• Foundation drains
• Air conditioning condensation (commercial/residential)
• Irrigation waters (does not include reclaimed water as described in 15A NCAC 2H.0200)
• Springs
• Water from crawl space pumps
• Footing drains
• Lawn watering
• Residential and charity car washing
• Flows from riparian habitats and wetlands
• De -chlorinated swimming pool discharges
• Street wash water
• Flows from emergency fire fighting
The City's permit should be referenced for the most current list of authorized discharges.
State Administrative Code
Several sections of North Carolina Administrative Code (NCAC) contain provisions authorizing discharges
by rule or regulation. Under 15A NCAC 02H.0106(f) (2003), additional non-stormwater discharges may
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be allowed, "provided that no water quality standards are contravened, or expected to be
contravened." Those discharges are:
1) filter backwash and draining associated with swimming pools;
2) filter backwash from raw water intake screening devices;
3) condensate from residential or commercial air conditioning units;
4) individual non-commercial vehicle washing operations;
5) flushing and hydrostatic testing water associated with utility distribution systems;
6) discharges associated with emergency removal and treatment activities for spilled oil authorized
by the federal or state on -scene coordinator when such removals are undertaken to minimize
overall environmental damage due to an oil spill;
7) groundwaters generated by well construction or other construction activities;
8) landscape irrigation, foundation or footing drains, or water from crawl space pumps;
9) street wash water;
10) flows from fire fighting; and
11) excluding the provision in Subparagraph (f)(6) of this Rule, discharges associated with biological
or chemical decontamination activities performed as a result of an emergency declared by the
Governor or the Director of the Division of Emergency Management and that are conducted by
or under the direct supervision of the federal or state on -scene coordinator and that meet the
following specific conditions:
a. the volume of discharge produced by the decontamination activity is too large to be
contained on -site;
b. the state Division of Water Resources is informed prior to commencement of the
discharge from the decontamination activity;
c. overland flow or other non -discharge options are deemed to be impractical by the
authorities conducting the decontamination activity; and
d. the discharge is not radiologically contaminated.
Additional sections of NCAC that provide for permitting by rule include 15A NCAC 02U.0113 regarding
utilization of reclaimed water. They also include various sections of 15A NCAC 02T which contain
requirements and procedures for permitting systems that do not discharge to waters of the state. This
section covers wastewater collection systems, reclaimed water systems, various onsite wastewater
systems that dispose of treated effluent by irrigation or infiltration, manure and biosolids land
application, and groundwater remediation systems. These permit -by -rule provisions generally do not
authorize discharges to surface waters. Both state law and wastewater collection system permits
require operators to report discharges to surface waters meeting criteria. Aside from a few pump -and -
treat groundwater remediation systems, investigators are unlikely to encounter the other listed sources
within city limits. If a discharge to surface drainage is found that involves one of these sources, the
investigator should consult with the Water Quality IDDE supervisor.
O]

Sources of Pollution Complaints
Investigations are initiated by a variety of methods including: complaints and concerns from city
residents and city employees, observations of city staff, water quality monitoring data, and dry weather
outfall screening.
Public Reporting Methods
The WQ Unit of Stormwater & GIS Services is organized to receive complaints in a variety of ways to
provide flexibility for users to report potential violations and to ensure that staff can receive the
complaints in a timely manner.
Complaint reporting methods include:
• Stormwater Pollution Hotline
o Users may call (919) 560-SWIM [7946] which will ring all investigations staff phones in
the Water Quality Unit
o After hours, or if all staff are unavailable, callers may leave a voicemail with complaint
details. All investigations staff have a duty to routinely check the hotline voicemail box
for unresolved complaints.
• Public Works Phone Directory
o Users may call [phone] and follow the automated menu to reach the Water
Quality Unit. This rings all investigations staff phones in the Water Quality Unit.
• Water Quality Unit email address
o All emails sent to [e-mail] are automatically distributed to
all Water Quality staff members.
o All investigations staff have a duty to routinely check their email for unresolved
complaints.
• Pollution Reporting Web Form
o This form is accessible via the Stormwater & GIS Services website
o All form submissions are automatically sent to [e-mail]
• Durham One Call Hotline
o The City advertises the [phone] hotline for uses to report any issue
o Durham One Call is supported by a computer decision -tree script that helps categorize
the issues in order to properly log service requests or direct calls. Water Quality
conducts training of Durham One Call staff to supplement the decision tree.
o Water Quality matters identified by One Call operators are forwarded by email to
[e-mail]
WQ Staff -Initiated Investigations
Some investigations are initiated directly by WQ Unit staff during the course of routine field work.
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Field Observations
WQ staff members are often outdoors conducting fieldwork or driving to locations throughout the city.
Staff members should use their experience and training to remain vigilant for evidence of illicit
discharges.
Stream Monitoring
The City of Durham has an extensive ambient water quality monitoring program that evaluates the
physical, chemical, and biological characteristics of local streams. In obvious cases, investigations may be
initiated by observation (including color and odor) at the time of sample collection. Data generated from
monitoring (in -situ measurements and laboratory samples) may trigger water quality investigations
when elevated pollutant indicator levels are observed. Indicator parameters and associated trigger
levels from in -situ measurements or laboratory sample results are published on the WQ Unit network
server. These triggers are assessed routinely and adjusted as necessary.
Dry Weather Outfall Screening
The dry weather outfall screening program is a requirement in the City of Durham's NPDES permit and
was designed to specifically target stormwater outfalls to detect and eliminate pollution sources. The
document entitled "Dry Weather Outfall Screening Guidelines and Procedures" details the methodology
and procedures that WQ staff members follow for this type of IDDE effort. Like stream monitoring,
outfall screening also generates data that may trigger water quality investigations. Indicator parameters
and associated trigger levels from in -situ measurements or laboratory sample results are published on
the WQ Unit network server. These triggers are assessed routinely and adjusted as necessary.
Safety Overview
The City of Durham's most valuable resources are its employees. Under any set of circumstances, an
employee's safety is a priority over any investigation task. Investigators must continually be aware of
potential hazards when conducting an investigation. Where potential hazards exist, investigators must
evaluate the potential hazard and take appropriate precautions to decrease the chance of injury.
City employees must read and understand the City's safety policies. Safety Policy S-201: Safety Program
indicates that "Each individual is in the very best position to ensure his/her own personal safety, which
will impact, not only the individual but others in his/her immediate work environment." S-201 goes on
to list requirements that every City employee must observe. Safety Policy S-206: On the Job Accident
Reporting and Procedures establishes requirements for employees and supervisors that will result in
prompt and accurate reporting of an accident, injury, or near miss.
Personal Protective Equipment
All city employees are required to use Personal Protective Equipment (PPE) appropriate for the task or
work assignment. Staff may procure most commonly needed PPE from the dispensary at the Public
Works Operations Center. Please talk to your supervisor if you need a particular type of PPE not
otherwise provided.
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As a baseline, steel- or composite -toed safety shoes are so often required to enter certain premises that
investigators should always wear them in the field. Safety shoes should be oil- and slip -resistant, since
oil residue is frequently encountered on the ground during investigations. Investigators will also
encounter requirements for hard hats and safety glasses often enough that they should be kept on hand
as well.
Injury Response and Reporting
The City of Durham general safety procedures are located on the City's intranet portal and in each
employee's hard -copy policy handbook. In the event of an emergency, call 911 or transport the injured
employee to the nearest hospital.
Employees are required to promptly report on-the-job accidents, injuries, and illnesses to their
supervisor and the Public Works Safety Officer, and follow the additional reporting requirements of
Safety Policy 5-206-2: On the Job Accident Reporting.
All employees must be familiar with and follow procedures and deadlines for all Workers' Compensation
claims. If an injury occurs during field operations, the supervisor or another team member will be
responsible for transporting the injured employee for medical attention as warranted.
Safety Assessment
Field investigators must react to a variety of scenarios when responding to complaints. Potential safety
concerns should be evaluated upon arrival at an investigation location.
Hazardous Materials and Conditions
911 should be called immediately if hazardous materials have been released or there are other
conditions that present danger to the public. WQ investigations staff are not trained in emergency
response and therefore should not remain within a hazard site during active control or remediation.
Durham County Emergency Response and the Fire Department are typically the first responders to a
release of hazardous material. WQ investigations staff should refrain from entering the area until
emergency response deems it is safe for non -emergency personnel.
Hostile Individuals
If at any time while conducting an investigation, investigators find themselves in a confrontational
situation with a hostile person or persons, the investigator should attempt de-escalation. If de-
escalation is unsuccessful, the investigator should withdraw.
After safely withdrawing, the City of Durham police department should be contacted and requested to
arrive on -scene to assist in completing the investigation.
Animals, both domestic and wild, can also present a danger and investigators should use their best
judgment in determining their safety risk.
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Roadwav Hazards
In some cases, it may be necessary to park along a roadway, or it may be necessary to inspect, observe,
or sample from a catch basin or other structure along a roadway. Staff must be aware of potential
hazards from roadway traffic. Safety measures (such as activating vehicle safety strobe lights, wearing
reflective safety vests, and setting out traffic cones) should be implemented to reduce road hazards.
In rare cases, it may be necessary to implement a traffic control plan to safely access manholes or other
structures. Most often, a traffic control plan is implemented during investigations conducted jointly with
Water and Sewer Maintenance, which involves blocking a lane of traffic and providing traffic control -
signal staff to safely route traffic. Investigators not familiar with traffic controls should consult with
more experienced staff, their supervisor, or the Public Works Safety Officer.
Other Hazards
Staff must be aware of other dangers of working in urban areas. Hazards that may be present include
sharps (glass shards, needles, wire, etc.), construction debris, uneven and slippery terrain, and trash.
Investigators must be vigilant to reduce the possibility of accidents and injury while conducting
investigations.
Staff should be aware of seasonal hazards such as exposure to cold, exposure to heat, insects and
snakes, and poisonous plants. Ticks and mosquitoes may carry insect -borne diseases such as Lyme
disease, Eastern Equine Encephalitis, and West Nile virus. Staff should take appropriate precaution in
selection of clothing, selective use of insect repellants, and a thorough check for ticks after every day in
the field. If an employee is especially sensitive to poison ivy, oak, or sumac then protective lotions or
clothing should be used.
Confined Spaces
Investigators need to be especially aware of OSHA regulations regarding confined space entry. During
the course of an investigation WQ staff members may need to enter a confined space, but certain types
of confined spaces should not be entered. A brief discussion on confined spaces follows below;
however, investigators should familiarize themselves with the specific regulations regarding confined
spaces.
29 CFR 1910 defines a confined space for general industry as follows:
Configurations of a work area that hinder the activities of employees who must enter, work in,
and exit them. A confined space has limited or restricted means for entry or exit, and it is not
designed for continuous employee occupancy. Confined spaces include, but are not limited to
underground utility vaults, tanks, storage bins, manholes, pits, silos, process vessels, and
pipelines.
Permit -required confined spaces (29 CFR 1910.146) contain hazardous conditions that pose a definite or
potential health risk which could result in a serious injury or death. These conditions include noxious
gasses, trapping and asphyxiating hazards, exposed live electrical wires, or unguarded machinery. WQ
investigators should never attempt to enter a permit -required confined space. If an investigator is
13

unsure of the conditions of a work area, then the Public Works Safety Officer or the Safety Officer from
the City of Durham's Risk Management Department should be contacted to determine if the work area
requires a permit to enter. WQ staff members should keep in mind that if a space does not meet the
regulatory requirements of being a confined space, this does not imply that the space is without
hazards. Relevant examples of categorically classified spaces are listed below:
• Sanitary sewer manholes, lift stations, and wet sumps — Permit -required Confined Spaces
(noxious gasses)
• Stormwater pipes less than or equal to 18 inches in diameter— Not a Confined Space
• Stormwater pipes greater than 18 inches in diameter — Non -permit Confined Space'
• Catch basins less than or equal to 36 inches deep — Not a Confined Space
• Catch basins greater than 36 inches deep — Non -permit Confined Space*
• Stormwater manholes — Permit -required Confined Spaces (oxygen deficiency)
Investigation Procedures
General Procedure Overview
Investigations vary, but generally all follow this routine:
1. Assess the complaint for critical details. Does WQ have authority over the matter? Is there
sufficient information to investigate? If necessary and possible, contact the complainant for
additional information.
2. Notify the WQ unit staff (typically via email) that the complaint is "claimed."
3. Create an entry in the WQ Investigations Database for the investigation.
4. Use the City GIS map and WQ Investigations Database to search for investigation and
enforcement history of the location and/or alleged responsible party named in the complaint.
5. Assemble necessary field equipment and PPE. Calibrate field meters if needed.
6. Travel to the complaint location and begin the investigation.
7. Gain lawful entry to premises as necessary.
8. Observe and collect evidence of non-stormwater discharges to the drainage system and/or
surface waters.
9. Trace evidence of the discharge upstream/upgradient to determine the source of the discharge,
if possible.
10. If the source can be ascertained, collect evidence of the party responsible for the source.
11. Contact the responsible party to discuss the findings of the investigation and direct corrective
action.
12. Enter investigation data into the Investigations Database, upload photos.
13. Issue a Notice of Requirement or Violation, if appropriate.
' Requires the investigator to remain in constant contact with another staff member residing outside of the
entered space.
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14. Return to investigation site to confirm corrective action completion, as necessary.
15. Conduct further enforcement and follow-up, as necessary.
16. Contact initial complainant to discuss investigation results.
Collection and Control of Evidence
When conducting an IDDE investigation, it is important that evidence be gathered using procedures
intended to recognize property and privacy rights.
All physical evidence (notes, forms, and pictures) is stored in a secured area on the third floor of City Hall
that is inaccessible to the general public. Additionally, electronic records stored on the WQ unit network
server are only accessible to staff with the proper network credentials. Only WQ staff and City
Technology Services staff have full access to these records.
Investigation Preparation
Information to Collect from Complainants
The essential information needed to begin investigating a complaint is a description of the
problem and a specific location.
Other helpful information is the name and address of the complainant (for calling back if
information isn't clear and to provide results of the investigation if requested), time of day
when the observation was made, associated stream or stormwater structure, citizen -provided
pictures and video, and any information about a business if one was involved in the possible
violation.
Jurisdiction
Before anything else, an investigator should use the City and County boundary GIS map
datasets to determine if the complaint is within the City's jurisdiction. Complaints outside of the
City's jurisdiction may not be investigated and should be forwarded to the appropriate County
or State agency.
Equipment and Supplies
Investigators should verify that they have the necessary equipment and supplies needed to
carry out the investigation. An investigator must use their judgment to decide what equipment
might be needed to identify, document, and track down a potential pollution source. Sampling
equipment, tracing dyes, water chemistry meters, field test kits, and tools may be required.
Some equipment and supplies are typically kept in vehicles, while other equipment is stored in
the office or WQ lab until needed.
Entry onto Premises
As detailed below, the City's process of collecting evidence is first to observe from public areas,
then ask for permission to enter property to conduct an investigation. In many cases, it is
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possible to fully document a violation without entering property. Other times, entry is
necessary to help assess the source and cause, and to evaluate what may be needed to remedy
the problem.
As a government agent, an investigator has a duty not to intrude on peoples' privacy. The
Fourth Amendment to the U.S. Constitution provides people with protection against
unreasonable searches by the government. In the context of WQ investigations, a "search"
occurs when an investigator enters upon property seeking out evidence of an ordinance
violation. It is considered unreasonable and illegal for an investigator to search an area that a
person (or business) takes steps to keep private.
If, during an illegal search, an investigator collects evidence of a violation, that evidence will be
excluded from use in enforcement actions against the accused violator (this includes any
"hearing" held by WQ, as well as any civil or criminal proceedings).
In the absence of permission to search a property, only the acceptable way for an investigator
to enter property to conduct a search is to obtain a search warrant. Investigators considering
this option must discuss the situation with the IDDE supervisor. Refer to the WQ unit document
"Guidance on Administrative Search Warrants" for instructions and best practices should this be
deemed necessary.
An investigator may conduct a search in a way that is not "unreasonable" when it is conducted either:
• from an area covered by the "plain view" doctrine; or
• on the premises with the consent of a person with authority to give it.
Evidence of a violation in plain view
If the investigator is lawfully present in a place where they can plainly see, smell, or hear the evidence,
there is no infringement of rights if the investigator records observations and uses them as evidence.
This means that evidence may be collected by observing conditions and violations from places like:
• City streets and sidewalks
• City easements
• City property
• Public areas such as parks
• Adjacent private property once the investigator is granted consent (or a warrant) to enter
• Business areas open to the public such as:
o Customer parking lots
o Sales floor
o Reception area
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Consent to enter premises
Consent of a person who has control over, the right to joint access of, or authority over a property must
be granted before an investigator records observations or collects evidence from areas that would be
unreasonable to search.
Who may izrant consent?
Often, investigators will be dealing with resident property owners, business owners, managers, and
supervisors who are explicitly authorized to grant consent to entry.
Tenants who lease property from landlords have possession of the property and the power of consent
to entry. A landlord may not grant valid consent to enter property leased to a tenant (unless the lease
specifies an exception). When dealing with co -tenants or co -owners, any of the tenants or owners may
grant valid consent to enter the premises. However, it only takes a single co -tenant or co-owner to
object or revoke the consent.
A non -owner or non -manager business employee may have authority to grant valid consent to enter the
premises if: 1) a higher-up has given him the appearance of authority (such as a uniform or "manager"
name tag/title); and 2) the inspector reasonably believes the employee to have authority, based on that
appearance.
When in doubt as to the validity of consent, an investigator should not enter the premises. Except in the
case of emergency, if an owner, manager, or other supervisor is not available, it is usually best to return
another time when such a person is available.
No person is required to give consent. Threats, tricks, bluffs, or coercion should not be used to gain
consent for entry. A valid tactic, however, is to inform the individual that your duties require you to
investigate, so you will be forced to apply for a search warrant. ("Apply" is emphasized, since to say
"get" is both hasty and borderline -threatening.)
Steps to follow in requesting consent to enter and inspect:
1. Identify yourself by name
2. Show your City ID badge
3. Request to speak with an owner, tenant, manager, supervisor, or other person in charge
4. Explain the purpose of your visit
S. Request permission to enter and conduct your investigation
The investigator should always include in their notes the names of individuals who granted, denied, or
revoked consent to enter.
Remember: Once granted, consent may be limited or revoked at any time.
Investigation Best Practices
Investigators responding to a water quality complaint should look for other water quality violations in
addition to observing evidence regarding the original complaint. Some investigations require only direct
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visual observations, such as illicit vehicle washing activities, while others require field testing to confirm
a violation has occurred. WQ investigators typically use field sampling equipment, indicator test kits, and
other water quality testing instruments to measure for indications of potential pollution.
Below are descriptions of common investigation techniques and practices.
Photographs and Videos
This is the most common form of tangible evidence collected during investigations. All WQ investigators
in the field must carry with them personal or City -issued mobile devices equipped with cameras (or, a
stand-alone camera in the alternative).
Photographs and videos valuable as evidence will help to establish several facts:
1) The nature of the violation;
2) The extent/scope of the violation; and
3) A link between the violation and responsible party.
Images must be framed such that the subject matter is in clear focus and there is sufficient context in
frame to be able to identify the location of the subject matter. If a series of photos is taken, then the
investigator should ensure that one or more photos in the series can establish location.
Source Tracking
Once contamination is suspected, there are various strategies and techniques that can be used to trace
the source. All of these techniques were developed to find and eliminate illicit discharges, but it is up to
the investigator to decide which is the most appropriate for a specific situation.
Tracing upstream sources using field meters and test kits is a reliable technique for tracking pollution
sources. However, a measureable parameter must be first observed to track upstream following an
increasing presence of that parameter or indicator. For example, ammonia used as an indicator for
sanitary sewage is reliable for tracking upstream sources. Low level measurements at the end of a pipe
or in a catch basin can be compared to upstream sources for increasing concentrations. This method can
also help determine which pipe at an intersection leads to the pollution source, while eliminating
another pipe/potential source. The pipe is then followed up to the next intersection where samples can
be taken. Investigators should then follow the increasing concentrations until a source is identified.
GIS Map Resources
Investigators have access to a range of GIS data on personal or City -issued mobile devices that can be
used to more efficiently guide efforts to locate a source. Mobile GIS applications can provide detailed
maps of sewer, storm, and potable utility networks, topography, surface waters, parcel ownership,
zoning, aerial photography, locations of industrial stormwater permits, etc. These resources can be used
to identify the general area of interest where the source should be located. They can also identify critical
branches in the drainage system, and sometimes identify potential sources to investigate.
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The GIS coverage of the drainage network is extensive. Stormwater pipes 12-inches and larger are
mapped throughout the City including on both public and private property. Generally, pipes smaller than
12-inches serve an individual parcel (home or business) and are not extensively mapped.
Having access to these GIS resources in the field facilitates using the more efficient source tracking
strategy of "splitting the trunk" and testing strategic locations. Testing at the midpoint of a long pipe
segment essentially cuts the target area in half; if the midpoint does not show contamination, the
investigator can back -track to another downstream location. If contamination is present, then the target
search area is upstream. A variation of this procedure is to sample at strategic locations where two or
more pipes come together, sampling each to determine which tributary is contributing the
contaminated flow.
Targeted investigation of specific candidate locations can be very efficient in certain situations. It is
sometimes possible to narrow the search to a small number of locations, based on knowledge of
businesses in the area, zoning, or other information so that the likely target may be related (i.e.,
automotive maintenance).
Tracing Dye Tests
Non -toxic tracing dyes are helpful when testing for suspected illicit connections or confirming properly
connected systems. Dye introduced into illicit or damaged connections will appear in the drainage
system, surface waters, or both. (Dye may also surface from underground pipe networks in some
circumstances.) Alternatively, dye introduced into a properly connected system will show up in the
sanitary sewer system.
Most typically, tracing dye is introduced into a toilet or sink in a residence or business. Best practice is to
flush water through the fixture after dye application. This will move the dye through the system and
may decrease the time it takes for the dye to be detected. If more than one suspected pipe or system is
involved, different tracing dye colors should be used to pinpoint the source. In some circumstances, it
may take several hours before the tracing dye is visible. Investigators should make sure to return to
check for dye in such circumstances.
If there is a potential for the tracing dye to discharge into the MS4 or surface waters, investigators must
send an alert message to [e-mail]. The message must contain the following
details:
• Date and time of dye test
• Location where dye was introduced
• Dye color(s)
• Nearest receiving stream
This is a distribution list that notifies multiple work groups and emergency responders that dye may be
expected to appear in a stream.
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Field Meters and Test Kits
Commonly used water testing devices include pH pens, conductivity pens, dissolved oxygen probes, and
turbidity meters. All devices must be calibrated before and post -checked after each use. Refer to the
document, "Standard Operating Procedures for Water Quality Field Meter Calibration and Maintenance"
for instructions. A log must be completed to document device performance during each of these steps.
WQ also has test kits stocked with supplies for evaluating ammonia, chlorine, and detergents
concentrations in samples. Ammonia is a common indicator of sewage discharge. Chlorine is a common
indicator of potable or pool water discharge. Detergents is a common indicator of wash water discharge.
Instructions for use of these test kits are included in their carry case.
Water Samples for Laboratory Analysis
At the direction of Water Quality supervisors or managers, investigators may collect laboratory samples
to confirm and quantify specific pollutants that field equipment is not able to detect. Samples must be
collected in accordance with the document, "Standard Operating Procedures for Water Chemistry
Sampling."
The investigator will be directed to communicate with a specific laboratory service provider to arrange
for sample bottle pickup and drop off.
Video Pipe Inspection
Sources of pollution can enter the MS4 through cracks or holes in underground utility lines. These often
cannot be identified without camera inspection. When City -maintained utility lines are implicated,
investigators may request camera inspection assistance from Stormwater Infrastructure or Water &
Sewer Maintenance. Such requests must first be discussed with the IDDE supervisor.
Sanitary Sewage Related Investigations
From the City -owned or operated system
A common investigation type is response to a Water & Sewer Maintenance report of a sanitary sewer
overflow. WQ investigators assist by tracking the sewage from its discharge point to its farthest extent in
surface waters. Ammonia test kits are used to evaluate stream water in these cases. The farthest extent
of a sewage discharge in stream is typically the point at which ammonia concentration is less than 2
mg/L. This extent is reported to the Water & Sewer crew, who will determine a feasible location for a
pump to be placed, then undertake remediation efforts. Pumps will typically run for 24 to 48 hours,
after which Water & Sewer will request an in -stream ammonia test from WQ to determine if the stream
flush successfully removed detectable ammonia.
From a privately -owned or operated system
Other sewage -related investigations involve private on -site wastewater treatment failures (from septic
and sand filter systems), illicit connections to a receiving stream or stormwater system, and leaking or
overflowing private sewer service laterals or pumping stations. Some of these may be discovered by
tracking high ammonia or fecal coliform numbers to a source, but are often reported by private citizens.
If a private system is found to be discharging, the investigators should work with the owners to ensure
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that they properly control and remediate the discharge. Enforcement should be used as necessary to
resolve the discharge.
General Practices applicable to both types of systems
If a discharge of sewage is suspected, investigators should test samples of the contaminated water using
ammonia field test kits. Ammonia concentrations of 2 mg/L or greater usually indicate the presence of
sewage and should initiate procedures to trace the source. Ammonia levels between 1 mg/L and 2 mg/L
should be viewed as suspicious, triggering additional evaluation by the investigator, which may be to
perform additional field tests for other indicators (conductivity, detergents, etc.) or to proceed to source
tracing, depending upon the circumstances. Care must be taken when sampling water using a
colorimetric indicator test kit to compensate for the background color of the water sample itself when
interpreting the results.
Illicit Vehicle Washing Operations Investigations
Vehicle wash water is considered to be a wastewater carrying in it many stormwater pollutants. Illicit
discharges of vehicle wash water may be either direct or indirect, depending on the circumstances.
Typically, investigations of improper vehicle washing are initiated by eyewitness reports from either WQ
investigators, other City employees, or from the public. A WQ investigator should respond to a
complaint of a vehicle washing violation as soon as possible to attempt to observe the responsible party
in commission of a violation.
To be in compliance with City Code, mobile vehicle washing operations must properly:
1) contain,
2) collect, and
3) dispose of vehicle wash water into the sanitary sewer system.
The WQ unit developed an authorization program for mobile car wash businesses to receive guidance
and approval of proper washing practices. To become authorized, the mobile washing business must
perform a demonstration for WQ staff to prove that its washing staff can properly and effectively
perform the above three requirements. If the demonstration is successful, an authorization form is given
to the business to keep with them at all times of operation and present upon request.
Vehicle Washing Rules Exemptions
Water Quality does not enforce the illicit discharge of these wastewaters under certain residential and
charity circumstances. The below rule exemptions were defined by the City Attorney's Office.
Residential Car Washing
Defined as vehicle washing which occurs at an individual's place of residence for the purpose of the
washing their vehicle(s) under the following conditions:
• Vehicle washing occurs on property zoned for residential use only.
• Vehicle being washed is not used for business purposes.
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• Individual(s) conducting vehicle washing reside at the location where the vehicle washing
occurs.
• Each vehicle being washed has a current vehicle registration card (available upon request) and
address listed on the vehicle registration card matches location where vehicle is being washed.
• No money is exchanged for services rendered.
Charity Car Washing
Defined as an occasional vehicle washing which occurs at a fixed location (non -mobile) for charitable
purposes by registered nonprofit corporations.
• Occasional is defined as no more than one occurrence per two months and no more than 3
occurrences per year.
• Occurrence is defined as a single event which does not exceed duration of more than 8 hours.
• Registered nonprofit corporations are defined as corporations that: (1) have properly filed their
company's Articles of Incorporation with the North Carolina Secretary of State Corporations
Division, (2) qualify as exempt organizations under sections 501(c)(3) and 170(c)(2) of the
Internal Revenue Code of 1986, and (3) have made required annual corporate and tax filings.
Charity Car Washing does not include regular vehicle washing activities conducted by nonprofit
corporations engaged in a business. Such corporations have the some impact on surface waters as for -
profit businesses engaged in the some activity.
Identifying and Contacting Responsible Parties
Investigators should keep in mind that if they find a problem or violation, they should contact the
responsible party as soon as possible; however, it may take some time and research to identify the
responsible party and to acquire contact information. The responsible party should be made aware of
the problem, expectations of corrective actions, and potential penalties associated with the
investigation.
Identifying a party responsible for property, a violation, or an issue can often be completed in the office.
Sometimes, if an investigator cannot get this information while in the field, this phase must be
conducted from the office.
Responsible, according to the City Code § 70-493(b), is defined as:
a person or party having direct or indirect control over the occurrence of an action, incident, or
condition. Responsibility includes the ability to control what occurs on property through
ownership of property, or through ownership, control, or management of a business,
organization, or other entity whose activities occur on property and cause in part or in whole
the action, incident, or condition. Causation may be through deliberate action or through
negligence, omission, or inattention.
"Person" and "party" are defined under § 70-493(b) as:
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any individual, partnership, co -partnership, LLC, firm, company, corporation, unincorporated
association, organization, joint-stock company, trust, estate, institution, governmental entity or
any other entity that owns a property, conducts a business, or controls management or
activities.
As such, "responsible parties" may include individuals or business owners that directly or indirectly
control the activities for a property where a violation has occurred.
Investigators have access to tools for determining ownership of property (land, buildings, etc.),
businesses, vehicles, and more.
Business Information
The Corporation search function on the NC Secretary of State website is useful in identifying business
owners that are difficult to track down by other means. Certain business filings (annual reports, etc.)
publicly available on this website may contain additional contact information, such as phone numbers.
Search results may vary. Not all business entity types require registration. Some businesses may be
unregistered or operating under a different assumed name.
Parcel Ownership
The investigator has two options for determining parcel ownership: 1) use of the "identify" function
within the City GIS parcel dataset; and 2) searching by address on the Durham County tax records
website.
Both methods will reveal the parcel owner name(s) and mailing address. Importantly, if the owner's
mailing address is not the parcel address, this is an indicator that the property is likely a rental unit and
may be tenant -occupied.
If the responsible party is a business operating in the City, the investigator may be able to contact the
City Finance Department to get phone numbers for the business. If the responsible party owns land in
the City, the Stormwater Billing unit may be able to find phone numbers as well.
Investigation Follow-ups
Follow-up investigations are conducted to document corrective actions taken by a responsible party, as
directed, in response to a water quality violation. Depending on the severity of the violation, how much
progress the responsible party has made, and deadlines for corrective actions, multiple follow-up
investigations may be required to ensure and document compliance.
All details, findings, and actions taken for the follow-up investigation must be entered into the WQ
Investigations Database.
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Code Enforcement
Before pursuing enforcement, the WQ investigator must have assembled sufficient evidence to link a
code violation to a responsible party.
This evidence may be assembled from multiple sources, including from the initial complainant. The
amount and quality of information that investigators get from the complainants varies widely. On some
occasions, a complainant will name a party allegedly responsible for a violation. Such an allegation
cannot stand on its own as evidence unless also accompanied by photo or video evidence. Only witness
accounts made by sworn officers and WQ staff may stand alone as evidence.
Collection of evidence using a combination of the best practices described earlier in this document often
creates the most solid foundation for justified enforcement.
WQ investigators must comply with the enforcement processes detailed in the document "Guidelines
for Enforcement of the Stormwater Management and Pollution Control Ordinance."
Spill Reporting
Reporting Major Spills to State Regulators, Generally
Per its MS4 NPDES stormwater permit (Reporting and Record Keeping Requirements section), the City is
required to report to State Emergency Management "all discharges that constitute an imminent threat
to health or the environment."
Investigators should report discharges if they might be toxic, if they involve a sufficient volume of
sewage that actually or might cause a fish kill, if they are likely to be reported to Emergency
Management because of the public impact (odor over a large area), etc.
These reports are to be made "within 24 hours by phone or email to the Division Regional Office during
business hours, or to the NC Division of Emergency Management State Operations Center hotline
outside of business hours."
The Emergency Management State Operations Center hotline number (also known as the State Warning
Point number) is 1-800-858-0368.
Reporting City or County Sewer Spills to the System Operator
The City and the County each operate a sanitary wastewater collection system within portions of the
City of Durham. The system operator is responsible for reporting spills from its system to the State. If a
sanitary sewer overflow or other discharge is identified, the investigator should report it immediately to
the appropriate City or County utility staff for assessment, repair, remediation, and reporting.
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Reporting Private Sanitary Sewer Spills to State Regulators
Discharges from private sewer lines and pumping stations "that constitute an imminent threat" should
be reported as soon as reasonably possible, but within 24 hours, by the investigator. In addition to the
guidelines in the previous paragraph, private sewage discharge should be considered an imminent
threat when:
• 1,000 gallons or more are discharged to the ground; or
• any amount of discharge to surface waters that causes dissolved oxygen less than 4 mg/L; or
• any discharge to a ditch or storm drain of 100 gallons or more.
The Emergency Management State Operations Center hotline number (also known as the State Warning
Point number) is 1-800-858-0368
Reporting Spills of Hazardous Substances to State Regulators
Hazardous substances are reportable only if the spill exceeds a reportable quantity threshold.
Reportable quantities for hazardous substances are available at the following website:
https://www.epa.gov/epera/consolidated-list-lists
The State DEQ Environmental Emergency phone hotline is 1-800-858-0368. When calling, be prepared to
give a statement including: the time and date of the spill, a description of the incident causing the spill,
the type of substance spilled, the approximate volume of the spill, the responsible parties, and any
containment or remedial actions done or underway. The investigator should make a note of the time
and date of the call, as well as the contact person. As of the time of this writing, the State does not
assign report numbers to these types of hotline calls.
Reporting Petroleum Spills to State Regulators
The reporting requirements for petroleum products are in North Carolina's Oil Pollution and Hazardous
Substances Control Act of 1978, N.C.G.S § 143-215.85(a) and (b):
IF the petroleum discharged, released or spilled:
• is 25 gallons or more, OR
• causes a sheen on nearby surface water, OR
• is 100 feet or less from surface water body,
THEN the person owning or having control over the oil must immediately take measures to collect
and remove the discharge, and report the discharge to NCDEQ within 24 hours of discharge, and
begin to restore area affected by discharge.
IF the petroleum released or spilled:
• Is less than 25 gallons, does not cause a sheen on nearby surface water,
• AND is more than 100 feet from surface water bodies,
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THEN the person who owns or has control over the oil must immediately take measures to collect
and remove the discharge. If it cannot be cleaned up within 24 hours of the discharge or causes a
sheen on nearby surface water, the person must immediately notify the NCDEQ.
If the petroleum released or spilled in any circumstances does not meet one of the above requirements,
or is not permitted by GS 143-215.1, or it is not pursuant to a rule adopted by the Environmental
Management Commission or, a regulation of USEPA, it must be reported to NCDEQ immediately.
The State DENR Environmental Emergency phone hotline is 1-800-8S8-0368. When calling, be prepared
to give a statement including: the time and date of the spill, a description of the incident causing the
spill, the type of petroleum spilled, the approximate volume of the spill, the responsible parties, and any
containment or remedial actions done or underway. Make a note of the time and date of the call, as
well as the person you spoke to. As of the time of this writing, the State does not assign report numbers
to these types of hotline calls.
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