Sec. 135-4. Protection of water quality.
(a) General.
(1) Water sources. The city, through its utility enterprise, Aurora Water, will identify water sources and critical infrastructure to be depicted by operator on its site plan for an oil and gas location to be submitted with the OGP application.
(2) Water supply. The operator shall comply with applicable laws, rules, and regulations concerning the source(s) of water used in the drilling phase, completion phase, and production phase. A fully executed water delivery agreement is required prior to operations. Per City Code, all water used within the City of Aurora shall be supplied by the city unless approved by city council.
(b) Surface water protection.
(1) Maintenance. Routine field maintenance of vehicles or mobile machinery shall not be performed within 500 feet of any waters of the United States or state surface water. All fueling must occur over impermeable material.
(2) Wastewater and waste management. Operator must submit a waste management plan to the city that complies with the following:
a. All fluids shall be contained, and there shall be no discharge of fluids except for unimpacted stormwater per federal spill prevention, control, and countermeasure plan (SPCC) regulations.
b. Flowback and produced water shall be transported by pipeline once constructed and available. If a pipeline is unavailable, flowback and produced water must be stored in tanks and transported by tanker trucks. All flowback and produced water must be disposed of at a licensed disposal site or recycled for use on site.
c. No land treatment of oil-impacted or contaminated drill cuttings is permitted. Disposal of oil-impacted or contaminated drill cuttings shall be disposed of at licensed disposal or recycling sites.
d. A copy of the operator's spill prevention, control, and countermeasure plan (SPCC) will be submitted to the city as part of the wastewater and waste management plan.
e. The operator shall not dispose of any wastewater, including but not limited to flowback and/or produced water, within the city.
(3) Stormwater Management. Operator must apply for and receive a city stormwater quality discharge permit for each oil and gas location in accordance with the City of Aurora's Rules and Regulations Regarding Stormwater Discharges Associated with Construction Activities. Erosion and sedimentation control are required for each oil and gas location. Operator must inspect and maintain stormwater facilities and control devices in accordance with City of Aurora Rules and Regulations Regarding Stormwater Discharges Associated with Construction Activities and/or section 138-442.5.
(4) Setbacks.
a. Setbacks from buried infrastructure. Operator shall site the oil and gas location a minimum of 350 feet from city buried infrastructure (critical infrastructure).
b. Setbacks from floodplains. Operator shall site the oil and gas location a minimum of 500 feet from 100-year floodplains (as defined in chapter 70).
c. Setbacks from reservoirs. Operator shall site the oil and gas location a minimum of one mile from all existing or planned reservoir sites.
d. Setbacks from domestic water wells. Operator shall site the oil and gas location a minimum of 350 feet from all domestic water wells.
(c) Groundwater protection.
(1) Water quality monitoring plan. The operator shall implement a water quality and well testing plan. Operator will submit water quality monitoring reports to the city. Operator shall avoid causing degradation to surface or ground waters within the city and to wetlands within the city.
(2) Baseline sampling. Using records of the Colorado Division of Water Resources, operator must implement a water quality monitoring and well testing plan that includes the following:
a. Operator must obtain initial baseline samples from all available domestic water sources within a one-half mile distance from the edge of the oil and gas location. Operator shall also drill one down-gradient monitoring well (operator drilled monitoring well) on that oil and gas location to sufficiently evaluate the baseline water quality and possible future impacts within each aquifer (alluvial, Dawson, Denver, Laramie-Fox Hills, and Arapahoe). The operator drilled monitoring well must be drilled and sampled for baseline prior to subsurface oil and gas activity. Operator will provide the city with the geophysical logs to ensure that aquifer layers are sufficiently identified for adequate sampling to occur.
b. Operator must collect initial testing of baseline samples from available water sources, including the on-site operator drilled monitoring well prior to the commencement of the drilling phase at an oil and gas location, or prior to the restimulation of an existing well for which no samples were collected and tested during the previous 12 months.
c. Post-completion phase samples of available domestic water sources shall be collected to test the domestic water supply for the city groundwater source in each aquifer (alluvial, Dawson, Denver, Laramie-Fox Hills, and Arapahoe). The operator drilled monitoring well at the oil and gas location will be tested annually for the Denver Basin aquifers (Dawson, Denver, Arapahoe (upper and lower) and Laramie-Fox Hills, and quarterly for the alluvial aquifer for the duration of the oil and gas location. The representative water source locations will be proposed by the operator but must be approved by the city.
d. Operator may rely on existing groundwater sampling data from any water source within the radii described above that was collected in accordance with accepted city standards, provided the data was collected within the 12 months preceding the commencement of the drilling phase for such oil and gas location, the data includes measurement of all of the constituents measured in Tables 135-4-1 through 135-4-6 below, and there has been no significant oil and gas activity within a one-mile radius in the time period between the original sampling and the commencement of the drilling phase for such oil and gas location.
e. Operator shall make reasonable efforts to obtain the consent of the owner of the water source. If the operator is unable to locate and obtain the permission of the water source, the operator must advise the city that operator could not obtain access to the water source from the surface owner. Operator shall drill one operator drilled monitoring well regardless of the existence of water sources available within a one-half mile distance from the edge of the oil and gas location and the commencement of the drilling phase for such oil and gas location.
f. Baseline water quality testing will be conducted for the analytes listed in Tables 135-4-1 through 135-4-6 below. Subsequent water quality testing will be conducted for the analytes in Table 135-4-7, annually for the Denver Basin aquifers and Laramie-Fox Hills and quarterly for the alluvial aquifer (water table existing between ground surface down to the top of the Denver Basin aquifers).
g. Operator must follow standard industry procedures in collecting samples, consistent with the current version of the COGCC Model Sampling and Analysis Plan.
h. Operator must report the location of the water source using a GPS with sub-meter resolution.
i. Operator must report results of field observations, including reporting on damaged or unsanitary well conditions, adjacent potential pollution sources, odor, water color, sediment, bubbles, and effervescence.
j. Operator must provide copies of all test results described above to the city, and the water source owners within 30 days after receiving the lab analytical results.
k. Operator must follow standard industry procedures in collecting samples, consistent with the current version of the COGCC Model Sampling and Analysis Plan.
l. If sampling shows the degradation of water quality, additional measures may be required, including:
1. If free gas or a dissolved methane concentration level higher than one milligram per liter (mg/l) is detected in a water source, determination of the gas type using gas compositional analysis and stable isotope analysis of the methane (carbon and hydrogen).
2. If the test results indicate thermogenic or a mixture of thermogenic and biogenic gas, an action plan to determine the source of the gas.
3. Immediate notification to the city, and the owner of the water source if the methane concentration increases by more than five mg/l between sampling periods or increases to more than 10 mg/l.
4. Immediate notification to the city, and the owner of the water source if benzene, toluene, ethylbenzene and xylene (BTEX) and/or total petroleum hydrocarbons (TPH) are detected. Such detections may result in required subsequent sampling for additional analytes.
5. The city may choose to sample the wells at its discretion and will provide the operator with reasonable notice to schedule a site visit. If the city chooses to perform its own sampling and testing, it will do so at its own expense.
m. Additional water well sampling may be necessary in response to verified complaints received from water source owners.
n. Timely production and distribution of test results in electronic deliverable format to the city and the water source owners.
o. All water source sampling and testing must be conducted by certified professionals.
p. If operator identifies degradation to water quality from the baseline testing as a result of its oil and gas development, operator shall report such results to the city and will be responsible for mitigating the degradation of water quality to the baseline levels.
q. If applicable, operator will submit a CDPHE Regulation 84 water user plan to comply as described in section 84.11 sections B, D, and F of Regulation 84.
Contaminant: |
|---|
Antimony |
Arsenic |
Asbestos |
Barium |
Beryllium |
Cadmium |
Chromium |
Cyanide (as free cyanide) |
Fluoride |
Mercury |
Nitrate |
Nitrite |
Total nitrate and nitrite |
Selenium |
Thallium |
Contaminant: |
|---|
Propane |
BTEX as benzene, toluene, ethylbenzene and xylenes |
Total petroleum hydrocarbons (TPH) |
Vinyl chloride |
Benzene |
Carbon tetrachloride |
1,2-dichloroethane |
Trichloroethylene |
Para-dichlorobenzene |
1,1-dichloroethylene |
1,1,1-trichloroethane |
Cis-1,2 dichloroethylene |
1,2-Dichloropropane |
Ethylbenzene |
Monochlorobenzene |
O-dichlorobenzene |
Styrene |
Tetrachloroethylene |
Toluene |
Trans-1,2 dichloroethylene |
Xylenes (total) |
Dichloromethane(methylene chloride) |
1,2,4-trichlorobenzene |
1,1,2-trichloroethane |
Contaminant: |
|---|
Alachlor |
Aldicarb1 |
Aldicarb sulfoxide |
Aldicarb sulfone |
Atrazine |
Carbofuran |
Chlordane |
Dibromochloropropane |
2,4-D |
Ethylene dibromide |
Heptachlor |
Heptachlor epoxide |
Lindane |
Methoxychlor |
Polychlorinated biphenyls |
Pentachlorophenol |
Toxaphene |
2,4,5-TP (Silvex) |
Benzopyrene |
Dalapon |
Di(2-ethylhexyl)adipate |
Di(2-ethylhexyl)phthalate |
Dinoseb |
Diquat |
Endothall |
Endrin |
Glyphosate |
Hexachlorobenzene |
Hexachlorocyclopentadiene |
Oxamyl (Vydate) |
Picloram |
Simazine |
2,3,7,8-TCDD (Dioxin) |
Perfluorooctanoic acid (PFOA) |
Perfluorooctane sulfonate (PFOS) |
Contaminant: |
|---|
Combined radium-226 and radium-228 |
Gross alpha particle activity (including radium-226 but excluding radon and uranium) |
Beta particle and photon radioactivity |
Uranium |
Contaminant: |
|---|
Aluminum |
Chloride |
Color |
Copper |
Corrosivity |
Fluoride |
Foaming agents (surfactants) |
Iron |
Manganese |
Odor |
pH |
Silver |
Sulfate |
Total dissolved solids (TDS) |
Zinc |
GENERAL WATER QUALITY Alkalinity, conductivity and TDS, pH, dissolved organic carbon (or total organic carbon), bacteria, and hydrogen sulfide |
MAJOR IONS Bromide, magnesium, potassium, sodium, and nitrate + nitrite as N |
METALS Boron, lead, selenium, strontium |
DISSOLVED GASES Methane, ethane |
OTHER Water level, stable isotopes of water (oxygen, hydrogen, carbon), phosphorus |
GENERAL WATER QUALITY Alkalinity, conductivity and total dissolved solids (TDS), pH, dissolved organic carbon (or total organic carbon), bacteria, and hydrogen sulfide |
MAJOR IONS Bromide, chloride, fluoride, magnesium, potassium, sodium, sulfate, and nitrate + nitrite as N |
METALS Arsenic, barium, boron, chromium, copper, iron, lead, manganese, selenium, strontium, mercury, uranium, and radium |
DISSOLVED GASES and VOLATILE ORGANIC COMPOUNDS Methane, ethane, propane, BTEX as benzene, toluene, ethylbenzene and xylenes, total petroleum hydrocarbons (TPH) |
OTHER Water level, stable isotopes of water (oxygen, hydrogen, carbon), phosphorus |
(3) Class II underground injection control wells. For operations associated with any oil and gas location, the operator shall not develop, use, operate or contract with any third party for the use of any Class II underground injection control wells within the city limits.
(4) Wellbore integrity and aquifer protection.
a. Operator shall follow all COGCC regulations regarding wellbore integrity and aquifer protection.
b. Operator shall obtain one water sample from each aquifer accessed by the operator drilled monitoring well after all final reclamation of all oil and gas facilities on the oil and gas location. The sample(s) shall be analyzed for the constituents in Tables 135-4-1 through 135-4-6 and the results reported to the city.
(d) Water during drilling phase.
(1) Closed-loop pitless systems for the containment and/or recycling of drilling fluids. Wells shall be drilled, completed, and operated using closed-loop pitless systems for containment and/or reuse of all drilling, completion, flowback, and produced fluids. Operator shall reuse fluids unless technically infeasible. All aboveground storage, including temporary tanks and separators, for use during drilling, completion, flowback, and other produced fluids shall have secondary containment.
(e) Use and transportation of water and hydrocarbons during completion and production phases.
(1) Pipeline construction time frame. Pipelines servicing a particular oil and gas location must be constructed before the production phase commences at such oil and gas location.
(2) Separate use of pipelines. Operator shall use separate pipelines for the transportation of raw water to and from the oil and gas location, and the transportation of hydrocarbons and produced water from the oil and gas location.
(3) During the completion phase, the operator will use flowlines and pipelines for flowback unless technically infeasible. All raw water related to completion activities shall be transported to the oil and gas location by pipeline.
(4) Permanent tanks. Tankless production sites are required unless the operator provides sufficient rationale for why permanent storage tanks are needed.
(5) Temporary use of tanks.
a. Operator shall be permitted to utilize temporary tanks during the drilling and completion phases, and during maintenance operations of the oil and gas location, flowline, or crude oil transfer line, provided operator has provided proper notice regarding location, and required screening for temporary tanks if the maintenance or temporary tanks are present longer than seven calendar days.
b. Temporary use of tanks at the start of the production phase may be approved by the oil and gas division if the operator presents a clear plan and timeline to connect to pipelines once available. In these instances, operator shall use industry-recognized alternatives to transport oil until the pipeline infrastructure is viable.
c. For maintenance operations that are expected to extend greater than seven days, operator shall give the city's oil and gas manager or designee prior notice of maintenance activities within three days of commencing the maintenance operations and the planned number of temporary tanks.
d. Operator may use temporary tanks for up to one month at an oil and gas location during any single maintenance operation without the need for adding appropriate temporary visual screening (e.g., hay bales).
(6) Water for landscape irrigation. All water use at the oil and gas location shall be pursuant to A.C.C. Chapter 138 and all other applicable regulations.
(f) Berms for fluid containment.
(1) Berm design.
a. The operator shall utilize steel-rim berms or lined earthen berms at the oil and gas location with sufficient capacity to contain one and one-half times the maximum volume of the largest tank that such oil and gas location will contain at any given time plus sufficient freeboard to prevent overflow around all permanent facility equipment.
b. All berms and containment devices shall be inspected quarterly by the operator and maintained in good condition.
c. No potential ignition sources shall be installed inside the secondary containment area unless the containment area encloses a fired vessel, or such sources are rated in accordance with industry codes and standards. Secondary containment such as duck ponds or lined earthen berms for temporary tanks may also be used.
(2) Permanent berms. Permanent containment berms shall be constructed of steel rings or lined earthen berms, designed and installed to prevent leakage and resist degradation from erosion or routine operation.
(3) Secondary containment. Secondary containment for tanks shall be constructed with a synthetic or engineered liner that contains all primary containment vessels and is mechanically connected to the steel ring to prevent leakage.
(4) Locations near surface water. For locations within 500 feet and up-gradient of a surface water body or floodplain, tertiary containment, such as a lined earthen berm, is required around production facilities.
(g) Flowlines and crude oil transfer lines.
(1) The operator shall construct a flowline or crude oil transfer line in accordance with specifications set forth in section 135-38 for the transportation of hydrocarbons and produced water. Operator shall comply with the requirements for flowlines and crude oil transfer lines set forth in COGCC regulations. All new flowlines and crude oil transfer line shall have the legal description of the location recorded with the clerk and recorder of the applicable county within 30 days of completion of their construction. Operator shall provide as-built GIS locations and maps of all flowlines, crude oil transfer lines, off-location flowlines, off-location produced water flowlines, and gathering systems.
(2) Flowline and crude oil transfer line construction.
a. The pipeline buried depth should be a minimum of 48 inches for all pipes outside of the city right-of-way (ROW). All pipes within the arterial city ROWs shall be a minimum of 20 feet depth. All pipes within all other city ROWs shall be a minimum of 15 feet depth. All pipelines installed beneath public ROW shall be bored unless otherwise approved by the city engineer.
b. Operator will conduct an x-ray or other nondestructive examination on all welds and conduct surveys and logging for every girth weld in place.
c. Operator will utilize jeeping (holiday detector) as well as visual inspection of the coating. Once a jeep (damage) is detected, pipe coating shall be repaired and rejeeped until the damage is repaired and does not cause a jeep or detection.
(3) Flowline and crude oil transfer line safety.
a. On all flowlines and crude oil transfer lines, leak protection and detection shall be provided through differential metering to meet zero tolerance levels for migration of product from the pipe envelope. Operator shall conduct additional leak detection through aerial surveys at least two times per year.
b. On all flowlines and crude oil transfer lines, operator shall annually hydrostatic test to the maximum operating pressure for four hours for exposed pipe and eight hours for buried pipe.
c. On all flowlines and crude oil transfer lines, operator shall utilize automated systems for overpressure protection and low pressure detection that shut-in the pipe in order for operator to investigate.
(4) Flowline and crude oil transfer line maintenance.
a. Operator shall conduct routine pigging on applicable flowlines and crude oil transfer lines (based on size).
(h) Floodplains.
(1) Additional regulations related to water preservation or protection may be imposed by the city staff during the OGP application process in order to mitigate risks of potential contamination to a floodplain.
(i) Drainage.
(1) Planning process and preliminary drainage reports. The OGP process requires the submittal of a preliminary drainage report for the oil and gas location and pumping stations. Preliminary drainage letters in place of a report will not be permitted.
(2) Civil plans—Process. Public works engineering will require a civil plan pre-submittal meeting to be held. To set up a meeting, please contact the engineer on call.
(3) Civil plans—Content and naming convention. Applications and checklists for oil and gas locations have been developed using the term "stormwater management plans (SWMPs)" in reference to the civil plans for these sites. The civil plans for oil and gas locations include features that go beyond typical SWMPs. Drainage reports (both preliminary and final) and civil plan submittals will be reviewed using city standards.
(4) Civil plans—Submittal package. Public civil plan submittals for an oil and gas location shall include the final drainage report, stormwater management report, and an inspection and maintenance plan as outlined at the civil pre-submittal meeting. Any grading within an existing utility easement may require structural loading evaluation to handle trucking loads as determined at the civil plan pre-submittal meeting. The structural loading evaluation shall be submitted with the first submittal of civil plans.
(5) Hydrologic analyses for drainage reports. The city's Storm Drainage Design and Technical Criteria Manual, along with Mile High Flood District Urban Storm Drainage Criteria Manual, shall be used to develop the hydrology for oil and gas locations. For oil and gas locations, 100-year precipitation depths shall be used for major storm event analyses. The entire tributary area, including the oil and gas location, draining to water quality/full spectrum (EURV)/detention BMPs shall be used to size those BMPs. Gravel surfaced pads shall use imperviousness (40 percent) and runoff coefficients consistent with the city's SDDTC Table 1.
(6) Hydrologic analyses—Conveyances, detention, WQ. For oil and gas locations, WQ/EURV/detention BMPs will be sized and designed in accordance with the standard requirements of the city SDDTC (e.g., extended detention basins). Stormwater detention and infiltration (SDI) data sheets shall be uploaded to the state website prior to civil plan approval. Culverts, open channels, and grass lined swales shall satisfy the standard requirements of the city SDDTC.
(7) Subsurface utility investigation—Loading information. For oil and gas location civil plans, the City of Aurora Roadway Specifications Subsurface Utility Engineering (SUE) Note 22 (which refers to C.R.S. 9-1.5-101 et seq.) is a required note to be placed on the plans. In addition, Aurora Water requires any crossing of existing utilities or tie-ins to provide pre-design potholing.
(8) Drainage easements—License agreements. For all oil and gas locations, the need for easements and license agreements shall be evaluated on a case-by-case basis. For oil and gas locations where the lease agreement with the property owner includes provisions for removing WQ/detention BMPs, the I&M plan for such BMP will negate the need for a drainage easement or license agreement for that BMP. If there is a need for a drainage or license agreement, these documents must be executed prior to civil plan approval. (Ord. No. 2021-15, § 4, 6-14-2021)