Stormwater Management Inspection SOP

Transcription

1 COGCC STANDARD OPERATING PRACTICES (SOP) 3.15 STORMWATER MANAGEMENT INSPECTION SOP Document Control: Created Date: May 6, 2015 Last Updated Date: May 6, 2015 Last Updated By: Dave Kulmann Review Cycle: Yearly Review Systems Used: Field Inspection Form Document Owner: Margaret Ash Background Purpose of this Document: The purpose of this standard operating practice (SOP) is to provide an internal tool for COGCC field inspectors to use during stormwater inspections of oil and gas locations with the goal of achieving greater consistency of stormwater inspections performed throughout the state. An ancillary benefit is providing greater clarity to oil and gas operators regarding what COGCC field inspectors will review related to stormwater so that operators can implement required actions to achieve greater and quicker compliance. Introduction: Stormwater management is an important part of protecting public health, safety, welfare and the environment, including wildlife resources. Sediment runoff rates from construction sites are typically 10 to 20 times greater than those from agricultural lands and 1,000 to 2,000 times greater than those from forest lands. During a short period of time, construction activity can contribute more sediment to streams than would normally be deposited over several decades, and while runoff is part of the natural hydrologic cycle, man made hydrologic modifications that accompany development has significantly increased the volume of stormwater runoff. Regulatory History: COGCC Rule 1002.f became effective, in this current language, April 1, 2009 and gives the COGCC authority over stormwater management on all oil and gas locations Stormwater Management Inspection SOP

2 during all phases of operations. It was implemented to consolidate the COGCC s previous stormwater best management practices (BMPs) that were listed in three different rules. The revised rules also complemented the existing CDPHE stormwater permit program and augment the COGCC s site preparation and stabilization rules. Below is a high level summary of Rule 1002.f: Rule 1002.f.(1) o Provides the general scope and intent of the rule. Rule 1002.f.(2) o Applies to all phases of oil and gas operations from pad construction to final reclamation. o Requires operators to implement best management practices (BMPs) to control stormwater, including run-on to a location and run-off from a location, in a manner that minimizes erosion and offsite transport of sediment and these BMPs should be implemented based on site specific conditions. o Lists six major categories of BMPs that operators should consider when they are implementing BMPs. o Tier 1 Oil and Gas Locations, as defined in the 100 series Rules, are not exempt from this section. Rule 1002.f.(3) o Applies only after the CDPHE stormwater permit is terminated, which is typically after interim reclamation is achieved. o Does not apply to Tier 1 Oil and Gas Locations as defined in the 100 series Rules. o Requires a post construction stormwater program. COGCC Program Objectives: The COGCC s stormwater program objectives are results or performance oriented whereas the CDPHE s program objectives have strong preventative focus, including a permitting process prior to site construction. While CDPHE focuses exclusively on maintaining surface water quality, COGCC focuses on the following: 1. Maintaining surface water quality (Rule 1002.f.(2)A). 2. Minimizing erosion and limit site degradation (Rule 1002.f.(2)). 3. Ensuring surface can be properly reclaimed (Rules 1002.e.(1), 1003 and 1004). 4. Minimizing alterations of natural features (Rule 1002.e.(1)). 5. Minimizing adverse impacts to wildlife habitat (Rule 1002.e.(3)). Definitions: These definitions are documented to provide additional guidance to COGCC inspectors on some commonly used terms. Last Revised 5/6/2015 Page 2 of 17

3 Best Management Practices (BMPs) -- practices that are designed to prevent or reduce impacts caused by oil and gas operations to air, water, soil, or biological resources, and to minimize adverse impacts to public health, safety and welfare, including the environment and wildlife resources. (From 100 Series Rules) Minimize adverse impacts -- wherever reasonably practicable, to avoid adverse impacts to wildlife resources or significant adverse impacts to the environment from oil and gas operations, minimize the extent and severity of those impacts that cannot be avoided, mitigate the effects of unavoidable remaining impacts, and take into consideration cost-effectiveness and technical feasibility with regard to actions and decisions taken to minimize adverse impacts. (From 100 Series Rules) Minimize erosion -- implementing best management practices that are selected based on site-specific conditions and maintained to reduce erosion. Erosion control practices include, but are not limited to, re-vegetation of disturbed areas, mulching, berms, diversion dikes, surface roughening, slope drains, check dams, and other comparable measures. (From 100 Series Rules) Natural Feature -- includes land or water features which are not man-made and can include mountains, arroyos, plateaus, rivers, lakes, ravines. Site Stabilization -- the process of implementing specific BMPs for the purpose of preventing the discharge of sediment from construction sites. Additional information on site stabilization can be found in the STORMWATER FACT SHEET CONSTRUCTION at OIL and GAS FACILITIES provided by the Colorado Water Quality Control Division. Site Degradation -- any unnecessary and undesirable change or disturbance to the location that may result from stormwater run-on, runoff, or impacts due to nonsediment pollutants Upset -- means an exceptional weather event that is outside the scope of reasonable and standard engineering design and planning. It is an incident in which there is unintentional and temporary noncompliance with the requirement to install and maintain BMPs. An upset does not include noncompliance to the extent caused by operational error, improperly designed BMPs, lack of preventive maintenance, or careless or improper operation. Best Management Practices (BMPs) Discussion and Differences: Stormwater BMPs are required per Rule 1002.f.(2) and the Rule lists six categories to consider. BMPs can come in many forms and practices and include both structural and nonstructural BMPs. Last Revised 5/6/2015 Page 3 of 17

4 Structural BMPs are used to treat stormwater at the point of generation, the point of discharge, or at any point along the stormwater "treatment train." Structural BMPs can serve many different functions based on their design. Non-structural BMPs are designed to limit the amount of pollutants available in the environment that would potentially end up in stormwater runoff. Non-structural BMPs can be achieved through such things as education, management, and development practices. Some examples include planning and design, inspection and maintenance protocols, good housekeeping, and comprehensive site planning. Erosion control BMPs are practices that prevent the erosion of soil and include (1) minimizing the amount of disturbed soil through phasing, temporary stabilization, or leaving existing vegetation and (2) diverting runoff around disturbed areas. Sediment control BMPs are practices to remove sediment from runoff and include (1) retaining stormwater in ponds or behind silt fence to settle out sediment and (2) filtering stormwater through filter fabric on inlets. The below table includes examples of both structural and nonstructural BMPs that can be implemented to manage stormwater. Both must be assessed by COGCC inspectors. Please note this list is not exhaustive and other methods not specifically listed may control stormwater. For examples of additional BMPs, refer to sources such as the EPA webpage on Construction Site Stormwater Control listed directly below and the CDOT Erosion Control Manual provided during your stormwater training. BMP Type Category BMP Example Structural BMPs Erosion and Sediment Control Straw Bales Wattles / Sediment Control Logs Silt Fences Earth Dikes Drainage Swales Sediment Traps Subsurface Drains Pipe Slope Drains Inlet Protection Outlet Protection Gabions Sediment Basins Non Structural BMPs Erosion and Sediment Control Temporary Vegetation Permanent Vegetation Mulching Geotextiles Sod Stabilization Slope Roughening Last Revised 5/6/2015 Page 4 of 17

5 Vegetative Buffer Strips Protection of Trees Preservation of Mature Vegetation Hay or straw bales Sediment traps/basins Vegetated buffers Non Structural BMPs General Good Housekeeping Waste Management Spill Prevention Inspection and Maintenance Program Planning and Design Construction Phasing and Sequencing Training for Contractors and Staff Documented Procedures Duties of the Inspector: Inspectors are expected to perform their task in a professional and diplomatic manner by objectively documenting all of the inspection findings. The inspection should be thorough, consistent, and cover all areas of the oil and gas location that require BMPs. Areas of Inspection: Areas covered by Rule 1002.f. include the following: Oil and Gas Locations as defined in the 100 series rules. Centralized E&P Waste Management Facilities as defined in the 100 series rules. Oil and gas access roads. Disturbed areas associated with Flowlines as defined in the 100 series rules. Gathering lines and public roads (see below for public roads) are not in the scope of COGCC s inspections related to stormwater. Inspection of Public Roads to the Location: The operator has no control over county or other public roads. Therefore, operators have little to no ability to maintain these roads for stormwater management and COGCC inspectors should not include any issues found on public roads in the inspection report. These could be informally discussed with the operator and the LGD if necessary or if safety issues exist. This does not apply to vehicles tracking mud or sediment offsite, which is addressed below in the Inspect vehicle tracking control BMP section. If mud or other Last Revised 5/6/2015 Page 5 of 17

6 sediment is tracked off of the location and onto any road, including public, the COGCC inspector should note this as an issue as discussed in the Inspect vehicle tracking control BMP section. At times, it might be difficult to determine if a road is a public road or an access road. If not known, inspectors should perform the required steps listed below to determine this: Review GIS layer, which lists public roads including highways and county roads. Review county records. Contact the LGD or county planning department. Ask the operator if they have documentation on who owns this road. Contact your supervisor. Overview of COGCC Stormwater Inspection Program The four appendices at the end of this document provide a general sequence and outline for conducting stormwater inspections and more detailed examples of the COGCC stormwater inspection program. Related to stormwater, COGCC inspectors focus their inspection on the following three areas: 1. Onsite Erosion. 2. Sediment movement offsite/onsite. 3. Non-sediment pollution sources. Onsite Erosion and Sediment Movement Offsite/Onsite: Note: The three steps identified below for onsite erosion and sediment movement offsite/onsite can be performed at the same time by the COGCC inspector but the necessary steps are separately discussed for purposes of clarity. Step 1 COGCC inspections related to onsite erosion and sediment movement offsite/onsite are performance based. This means a COGCC inspector, for all areas of inspection described above, should look for the following: 1. Evidence of onsite erosion such as gullies, rills, or ruts. 2. Evidence of sediment runoff from the areas of inspection. 3. Evidence of sediment run on to the areas of inspection. If evidence of any of the above is identified, the COGCC inspector should document the impact, size, location, and associated risk level of the issues in the inspection report, including photographs. Specifically, the report should include language addressing the following: Last Revised 5/6/2015 Page 6 of 17

7 Does the issue pose a potential threat to any of the objectives listed in the COGCC Program Objectives section above? Is the issue isolated to a small area or does it cover a majority of the area? Are the actual gullies or rills large in size (use judgement on what large means)? Where on the area of inspection is the identified issue (e.g. SE corner)? As an example, if an inspector identifies an area of inspection that contains several gullies, the inspector should measure a reasonable subset of the gullies (using measuring devices including, but not limited to, range finder, measuring wheel, tape measure, GPS units, or stepping it off) and document the measurements in the inspection report. This information will help COGCC staff and operators better understand the size of the issue. Also, the above factors should be documented and considered when writing the inspection report. If any of the above items are identified, COGCC inspector must determine if an upset weather event could have caused the impact and whether the operator is proactively working to address the issue. This will help determine the steps as outlined in the Inspection Report section below. Step 2 The inspector should then inspect all sediment control BMPs that are designed to catch and store sediment onsite to ensure the following: 1. The BMPs are inventoried for the inspection report. 2. BMPs are capable of working as intended. 3. There is no imminent risk of failure or overflow of sediment. Inspectors should interpret imminent risk of failure to mean the sediment control BMP is full of sediment and one more weather event of any size would cause sediment to overflow and runoff the area of inspection. NOTE: Stormwater is allowed to leave the location as long as the stormwater is not carrying sediment offsite. If evidence of issues with these sediment control BMPs exist, COGCC inspector should clearly document these issues in the inspection report, including photographs. Step 3 The COGCC inspector should then identify the erosion control BMPs, runoff / run on control BMPs, and non-structural BMPs on the areas of inspection and perform the following: 1. Inventory the BMPs for the inspection report. 2. Perform a review of the existing BMPs looking for obvious flaws or maintenance concerns that could cause an impact. Detailed sizing calculations will not be performed. Last Revised 5/6/2015 Page 7 of 17

8 a. Examples of obvious flaws or maintenance concerns include mulching washed away or slope diversions damaged or altered. 3. Review the structural BMPs to ensure no major installation issues exist that could cause an impact. a. Example of an installation issue includes putting only one stake in a wattle. Both structural and non-structural BMPs must be assessed during this review. The appendices will go into specific examples related to access roads and location. In performing this step, the inspector must evaluate the collective performance of all BMPs installed. These means if there are issues with one BMP but other downstream BMPs are working as intended and site degradation is not occurring as a result, then the fact that, collectively BMPs are working, needs to be noted in the inspection report. Non Sediment Pollution Sources: COGCC inspectors must then identify all non-sediment pollution sources located on areas of inspection. The following is a non-inclusive list of non-sediment pollution sources: 1. Fuel cans. 2. Fueling equipment. 3. Frac tanks. 4. Water tanks. 5. Bulk drilling fluid additives and cuttings drying material. 6. Vehicle maintenance areas. 7. Vehicle fueling area. 8. Equipment storage. 9. Chemical additives. 10. Lube oil or other chemical products. Once the COGCC inspectors identify all of the non-sediment pollution sources, they must identify the BMPs that control releases from these sources. Some of the same BMPs used for sediment may apply to these sources. As with the sediment BMPs, the COGCC inspector must: 1. Inventory the BMPs for the inspection report. 2. Perform a review of the existing BMPs looking for obvious flaws or maintenance concerns. Detailed sizing calculations will not be performed. 3. Review BMPs to ensure they were appropriately installed. Portable latrines located on areas of inspection could be an issue with CDPHE s rules but not necessarily with COGCC rules. If the inspector notices a portable latrine without secondary containment, the inspector will simply put the following Last Revised 5/6/2015 Page 8 of 17

9 general comment without a corrective action date in the inspection report: CDPHE may require secondary containment around portable latrines. COGCC inspector identified a portable latrine without secondary containment. This is not a corrective action required for this report but could be an issue if the CDPHE inspects this location. The inspector should not mark this as an action required issue. Inspection Report: Field Inspection Documentation COGCC staff should use the COGCC inspection report to document BMP inventory, results from the above inspection steps, and areas that require corrective actions identified in the above steps. The report should be objective and detailed. Photographs As discussed several times above, COGCC inspectors must take photographs of impacts identified during the inspection along with BMPs and attach the photographs to the inspection report. When issues are discovered, the report must include photographs close enough to show specifics and photographs from a distance to show the surrounding background conditions. Including both types of photographs provides context for the impact or issue identified. When taking a photograph, keep perspective in mind. If the viewer will have difficulty understanding how large something is (for example, a rill/gully), then use a prop such as a person, shovel, hardhat or other object to provide perspective. Scenario Examples COGCC inspectors should contact their supervisor with questions related to documenting stormwater issues in the COGCC inspection report. Below are some scenarios that will provide inspectors guidance on how to document certain situations. These are just guidelines and a site specific analysis, such as risk to water features and repeat issues, allow COGCC inspectors to deviate from the below examples. 1. If the inspection shows that sediment or non-sediment pollution left the area of inspection and entered a water feature (such as perennial stream, intermittent stream, lake, or pond), the COGCC inspector will document an Action Required inspection report and this should be elevated to the Field Inspection manager for next steps. 2. If the inspection shows there were identified impacts as described above (e.g. erosion, gullies, rills, etc.) but sediment or non-sediment pollution did not leave the area of inspection, the COGCC inspector will document an Action Required inspection report to fix these issues and work with the operator as required. 3. If a recent upset storm event caused the impacts identified above and evidence exists that the operator has been working, prior to the inspection, to fix the BMPs, the COGCC inspector will document a Satisfactory report with Last Revised 5/6/2015 Page 9 of 17

10 comments to encourage the operator s continued repair of the BMPs. The inspection report should clearly document what the operator has already performed and their proposed fixes that are not yet completed. 4. If the inspector did not identify impacts as described above but did identify minor issues with maintenance or installation of BMPs, the COGCC inspector will document a Satisfactory report with comments and note the minor issues and required actions in the comments of the inspection report. 5. If the inspection shows no stormwater issues, the COGCC inspector will document a Satisfactory report, assuming no other inspection related issues existed. 6. Other scenarios should be discussed with the inspector s supervisor and determined on a case-by-case basis. Corrective Action Language and Timing The following will be the corrective action language for most stormwater related issues: Perform required actions by [30 DAYS FROM WHEN REPORT SENT TO THE OPERATOR] or if not possible to complete required actions by this date, provide a work plan, with associated timeframes, by [10 DAYS FROM REPORT SENT TO OPERATOR] that details the actions the operator will perform within the associated timeframes. Generally, it is important for inspectors to provide operators 30 days to perform the required actions or 10 days for a work plan from the date the inspection was sent to the operator and not the date of inspection. For example, if the inspection was February 22, 2015 but the report was not sent to the operator until March 1, 2015, then the corrective action dates should be March 31, 2015 to correct or March 11, 2015 for the work plan. For action required inspection reports, inspectors must request that operators submit a Form 42 when corrective actions have been completed. Inspectors will then reinspect at an appropriate time after receipt of that Form 42. Some exceptions to the 30 days listed above include the following: 1. Instances where there is an immediate threat to surface water quality. In those cases, the operator should correct the issue immediately. 2. Instances where a COGCC inspector found the same stormwater issues on the same location in the same general area in a previous inspection report. In those cases, a shorter duration may be appropriate and discuss with your supervisor. 3. Perimeter controls during construction of the location. Since construction of the location will end within 30 days, these controls should be implemented immediately. In these cases the inspector should contact the operator to set a timeframe and schedule. Last Revised 5/6/2015 Page 10 of 17

11 It is important to note that these are guidelines for COGCC inspectors and 30 days provides a reasonable timeframe for a COGCC inspector to be able to reinspect the location. COGCC strongly prefers for operators to correct issues as soon as possible and not wait until day 29, and inspectors should share this preference with operators. If asked, inspectors should also remind operators that if CDPHE inspects the location within the 30 days and finds the same issues, the operator is at risk of an NOV from the CDPHE. Natural Erosion Areas The COGCC inspector, after discussions with a supervisor, should document in the inspection report areas of inspection that have significant natural erosions features nearby, which the natural areas might contribute to the stormwater issues. Sediment movement confined to the oil and gas location, related to natural erosion, and which is an indication of alteration of natural features should not warrant an NOAV, but may require corrective actions to reduce sediment movement and site degradation. Staff should work with operators to assist in identifying higher risk sites that have significant natural erosion features that may require a higher frequency of inspections and BMP maintenance by the operator due to these natural erosion features. These high risk factors may include proximity to drainage areas, proximity to streams, slope gradients, and potential for flooding. NOAVs: NOAVs will not be issued to an operator for stormwater related issues unless first reviewed by both the Field Inspection Manager and the Hearings Manager. The Field Inspection Manager and the Hearings group will review to ensure that adequate physical evidence exists to support the issuance of an NOAV. Appendix 1 General Construction Inspection SOP A note about construction activity: Construction activity, by its very nature, is a dirty business. In many cases, land is cleared and graded to conform to the new site requirements. During a rain event or snow melt, even the best-managed construction sites will look muddy. An inspector s role during an inspection is to perform the inspection with the objectives listed in the COGCC Program Objectives section above in mind. Inspection Sequence: 1. Plan your inspection Last Revised 5/6/2015 Page 11 of 17

12 Stormwater inspections could be conducted during initial construction activity when clearing, grubbing, grading or other earth disturbing actions are in progress. Stormwater construction inspections will also be part of any COGCC Location Inspection at sites that have not passed an interim reclamation inspection. Initial construction (earth moving) inspections will typically be conducted by the reclamation specialist. Review the aerial photographs or site map in the 2A and plan how you will conduct the inspection (this is particularly important for large construction sites). Identify the significant sources of pollutants and BMPs to inspect such as silt fence installation, sediment basins, slope stabilization, material storage areas, etc. Consider the stormwater flow direction as you plan the inspection. Consider beginning your inspection at the low point on the location, observing all discharge points and walk up the slope to inspect the rest of the site. 2. Areas to inspect Refer to the Areas of Inspection section above to identify sites that are within COGCC jurisdiction. 3. Inspect discharge points and downstream, off-site areas for signs of impact When inspecting discharge points from the site, if it appears that sediment is leaving the site, walk downstream to document the extent of travel and impact on receiving waters or storm drain systems, such as road ditches. Walk down slope if necessary to inspect off-site areas for signs of discharge. Inspect catch basin inlets to ensure that they are adequately protected. Note in the inspection report all environmental impacts and document these impacts with photographs. Appendix 2 -- Inspection of Access Roads to the Location Access roads are those roads built and/or maintained by operators for the main purpose of accessing the oil and gas location. The operator, or group of operators, has direct control over the road. Access roads are not public roads. Inspect condition and slope of the access road: COGCC inspectors may look for the following: 1. Access road not stabilized. Last Revised 5/6/2015 Page 12 of 17

13 2. Access road not constructed or maintained appropriately to allow stormwater to drain from the road to drainage ditches, culverts, or other sediment catchment basins. 3. Pot holes and ruts. o Ruts on access roads of 4 inch depth or evidence of vehicles avoiding ruts or pot holes should require corrective actions. o Ruts less than 4 inch depth should be noted in the comments of the inspection report but generally should not have a corrective action associated with the comment. 4. Areas where vehicle traffic is driving off established road surface to avoid ruts, pot holes, or standing water. 5. Evidence that cut slope stabilization is introducing sediment to the access roads. 6. Evidence that road maintenance activities are, or potentially are, allowing sediment to approach water features. Inspect drainage channels on both sides of the access road: COGCC inspectors may look for the following during this review: 1. Evidence of erosion. 2. Road damage (from operations or maintenance) that may cause run off. 3. Evidence of wash out, gullies, rilling, and erosion channels along the edge of the road. Inspect all check dams, wattles, water bars, and retention ponds located along access roads and inspect outlet protection around retention ponds: COGCC inspectors will look for the following during this review: 1. Retention ponds not armored to prevent undercutting. 2. Check dams not installed properly to prevent erosion. 3. BMPs not installed, not installed correctly, or not maintained. Inspect all culverts along the access roads and inspect outlet protection at culverts: COGCC inspectors will look for the following during this review: 1. Damage to culverts or evidence of poor maintenance of culverts. 2. Sediment build up around or in culverts that prevents the culvert from functioning as designed. 3. Inadequate inlet and outlet protection that prevents the culvert from functioning as designed. 4. Improperly constructed retention pond or catchment basin within the culvert. 5. Improperly designed or installed culvert that allows energy of moving water to cause erosion. Last Revised 5/6/2015 Page 13 of 17

14 How to Address Issues Found with Access Roads: If issues with access roads are identified from the above review where an action required inspection report is issued, the inspector should perform the following based on the below situations: 1. Access road is used by only one operator (No evidence that it is a private road): o Inspector should send the report to that operator. The inspector should also add the following language to the inspection report: The COGCC has no information that this is a private road or a road shared or owned by other private interests (other than the landowner). If this is the case, as part of your corrective action, please provide information related to what responsibilities you have to maintain the access road. The COGCC is available to discuss this issue as required. 2. Access road is shared by more than one operator: o Inspector should send a separate report to each operator describing the issue found. The reports must include the following language in the stormwater section: The COGCC recognizes that multiple operators use this access road. However, the COGCC does not have the ability to know which operator is responsible to maintain the access road and has therefore sent a similar inspection report to OPERATOR NAME. The COGCC encourages you to coordinate with OPERATOR NAME to resolve the issue. The COGCC is available to discuss this issue as required. o Inspector, with inspection supervisor as required, will meet with the operator or operators to discuss if requested. o Generally, an NOAV will not be issued unless a discussion with the operator first occurs. 3. Access road is shared with, and/or owned by, private non-oil and gas interests: o Inspector should send the report to the operator. The report must include the following language in the stormwater section: The COGCC recognizes that this road is shared, and potentially owned, by private interests other than oil and gas operators. However, the COGCC does not have the ability to know what responsibility the operator has to maintain the access road. As part of your corrective action, please provide information related to what responsibilities you have to maintain the access road. The COGCC is available to discuss this issue as required. o Inspector, with inspection supervisor as required, will meet with the operator to discuss if requested. o Generally, an NOAV will not be issued unless a discussion with the operator first occurs. Last Revised 5/6/2015 Page 14 of 17

15 Appendix 3 -- Inspection on the Location: Determine all non-sediment pollution sources located on the location: As documented in the Non Sediment Pollution Sources and Associated BMPs section above. Inspect all temporary berms implemented around equipment located on the location (not perimeter berm): COGCC inspectors will look for the following during this review: 1. Berms not compacted or damaged. 2. Berms not maintained properly. NOTE: This SOP is not stating temporary berms are required around all such equipment. The SOP is simply stating if a temporary berm is being used as a stormwater BMP, then these BMPs, like any other BMP, must be working appropriately. Inspect for site degradation on the location: COGCC inspectors will look for the following during this review: 1. Location is not stabilized appropriately, which would include lack of compaction, insufficient gravel, or existence of ruts, etc. o Ruts on a pad in three or more different areas that are all 4 inches or deeper should require corrective actions. o Ruts below the above criteria should be noted in the comments of the inspection report but not have a corrective action associated with it. 2. Areas of site degradation on the location exist that can cause run off. 3. Evidence of erosion (riling, gullies, channeling). 4. Catchment basins are at imminent risk of discharging sediment. 5. Rig wash allowed to run onto location with no control. 6. Spills and releases of chemicals uncontrolled on location. 7. Insufficient BMPs for the size of the location. For example, location sloped to direct stormwater to one area, but the ditch in that area is not sufficient in size to contain the sediment. Inspect vehicle tracking control BMP: COGCC inspectors will look for the following during this review: 1. Evidence of tracking sediment or mud off of location, and may include tracking, onto an access road or public road. 2. Look for BMPs (tracking pad, wash rack, scraping, or other sediment controls). 3. Review condition of vehicle tracking pad if present. Last Revised 5/6/2015 Page 15 of 17

16 4. Review condition of cattle guard, if cattle guard is being used as a stormwater BMP. Observe run on and run off potential on all sides of the location: COGCC inspectors will walk the perimeter of the location and look for the following during this review: 1. Evidence of run off or run on of sediment due to lack of appropriate control measure. 2. Perimeter berm, if one exists, not compacted, damaged, or otherwise stabilized. Appendix 4 - Common Compliance Problems The following compliance problems are commonly found at small construction sites. Inspectors should keep these common problems in mind while conducting inspections. Problem #1 No temporary or permanent cover. In areas of the site where construction has temporarily or permanently ceased, exposed soil areas should be stabilized. Problem #2 No sediment controls on site. No sediment control practices (e.g., sediment traps/ basins, down-gradient silt fences or sediment barriers, check dams, etc.) were implemented on down-gradient perimeters before up-gradient land disturbing activities begin. Problem #3 No sediment control for temporary stock piles. Temporary stockpiles should have silt fence or other effective sediment BMPs. Problem #4 No BMPs to minimize vehicle tracking of sediment or mud off of the area of inspection. Vehicle exits should use BMPs such as stone pads, wash racks, or equivalent systems to prevent vehicle tracking of sediment or mud off of the area of inspection. Problem #5 Improper solid waste or hazardous materials management. Trash and other debris should be disposed of properly, and hazardous materials (including oil, diesel fueling, glycol, etc.) should be properly stored and have specific BMPs in place, such as secondary containment. Last Revised 5/6/2015 Page 16 of 17

17 Document Change Log: Change Date May 6, 2015 Description of Changes Document created and finalized Last Revised 5/6/2015 Page 17 of 17