FEDERAL ENERGY REGULATORY COMMISSION FIELD INSPECTION REPORT

Transcription

1 FIELD INSPECTION REPORT Date June 19, 2018 Project Northern Natural Gas Company (Northern) Cedar Station Upgrade Project Dakota County, Minnesota Authority: Section 7(c) Personnel FERC Staff: Company Staff: David Hanobic Terry Plucker and John Bass, Jr. (Northern) Inspection Summary 1 Problem Area(s) 0 Noncompliance(s) No No Follow-Up Letter Required Refer to Enforcement Introduction On June 19, 2018, David Hanobic of the Federal Energy Regulatory Commission (FERC or Commission) performed a construction inspection of the Cedar Station Upgrade Project. The project consists of: construction of about 7.86 miles of 20-inch-diameter pipeline loop 1 ; construction of a pig 2 launcher and takeoff valve setting at milepost (MP) 0.0 within the existing Rosemount Junction facility boundaries; construction of a pig receiver, tie-in valve setting, and modification of existing regulators within the existing Cedar Station boundaries (MP 7.86); and replacing a 10-foot-long segment of 12-inch-diameter pipeline with the same size and diameter pipeline and replacing about 105 feet of 8-inch-diameter bypass pipeline with 260 feet of 10-inch-diameter pipeline, both within the Cedar Station boundaries, to facilitate tie-ins of the new pipeline to existing station piping. 1 A pipeline loop is a segment of pipe installed parallel to an existing pipeline. 2 A pig is an internal pipeline tool used to clean a pipeline and/or to inspect for damage or corrosion. 1

2 The project in-service date is tentatively scheduled for November 1, FERC staff and company representatives listed above were present throughout the inspection. The purpose of the inspection was to determine Northern s compliance with the environmental conditions of the Commission s August 22, 2017 Order Issuing Certificate for the subject project and to inspect the condition of the right-of-way (ROW) and construction workspaces. The findings of the inspection were that one problem area, but no instances of noncompliance, were observed. A site map and photographic record are also presented in this report. Inspection On June 19, 2018, the weather conditions were cloudy with and showers with temperatures in the mid 60 s (degrees Fahrenheit). Approximately 5.0 inches of rain was recorded during the past ten days, including a 3-inch, 24-hour rainfall event, and a 1.1-inch rainfall event, along the ROW. The inspection begin at Cedar Station at the northern end of the project. The entrance to the ROW at station number was inspected. During the previous inspection, the participants discussed the installation of hay bales to prevent silt-laden water from leaving the ROW (Photo Number [Photo No.] 1. It was raining during the inspection, and because this area was an active construction entrance, the hay bales were moved frequently. This prevented a seal from forming and allowed silt-laden water to exit the ROW, which resulted in a problem area. The inspection participants discussed different methods to control water leaving the ROW such as a rock entrance or matting. The inspection continued to the Horizontal directional drill (HDD) of the baseball fields (station number ), where Northern received a variance to move the exit point of the HDD on June 15, 2018 (photo No. 2). Secondary containment was installed around the frac-tanks and noise walls were installed around the drill rig. The hydrovac truck was louder than the drill rig during the time of the inspection. Orange safety fence was installed along the ROW adjacent to the residences and school in the area. Highline Trail at Johnny Cake Ridge Road (station number ) was relocated to the south side of the ROW (Photo No. 3). Orange safety fence was installed on both sides of the trail and along the edge of the ROW adjacent to houses. Silt fence was installed on the downhill side of the ROW. A sinkhole developed during reaming of the HDD in Lebanon Hills Regional Park (station number east, Photo No. 4). The HDD out of Lebanon Hills Regional Park had not resumed following the sinkhole development. Northern s initial plans are to drill adjacent to the existing pipeline to test soil resistance. Northern indicated it will install grout in the area of the sinkhole to ensure stability and then replace subsoil and topsoil. The construction entrance at Interlachen Drive (station number ) was free of mud (Photo No. 5). The HHD entry and exit points near Buck Pond were inspected. Silt-laden storm water was pumped at station number from behind the silt fence into a frac-tank. The pump was in secondary containment. The pumping and the double silt fence prevented sediment laden water from entering Buck Pond (Photo No. 6). Three inadvertent returns occurred near the HDD entry and exit points adjacent to Buck Pond and wetland W-24. The inadvertent returns occurred June 17, 18, and 19, The two older inadvertent returns occurred near station The inadvertent return that occurred on June 17 th (about 125 gallons) did impact wetland vegetation, but was cleaned and resulted 2

3 in little impact on the wetland and no impacts were noticeable in the open water (Photo No. 7). The inadvertent return that occurred on June 18 th (about 100 gallons) did not enter the wetland and was contained to the upland (Photo No. 8) and was cleaned during the inspection. The third inadvertent return occurred close to the exit in the HDD workspace (30-40 gallons) and was mostly vacuumed up by the time of the inspection. The HDD entry into Lebanon Hills Regional Park from the southern side was inspected (station number ). The HDD was not active because the drill rig for the more northern HDD of Lebanon Hills Regional Park was on top of the planned exit point. Topsoil piles were placed on the edges of the HDD workspace and were stable with annual oats sown and growing (Photo No. 9). The inspection continued to wetland W-07 (station number 73+67). Silt fence was installed at the wetland boundary (Photo No. 10). The wetland was matted for both pipe stringing and for a travel lane; the former will be removed when the pipe is installed in the wetland. Conclusions and Recommendations A follow-up letter is not required at this time because no instances of noncompliance were observed. Overall, conditions along the ROW were acceptable. In response to the problem area, Northern committed to provide the steps it will take to minimize the amount of sediment laden water that could leave the ROW at station number , which may include installing a rock entrance or matting. Another construction inspection is scheduled for the week of July 9, 2018, to inspect and document the environmental conditions of the Project. 3

4 SITE MAP 4

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6 PHOTOGRAPHIC RECORD Company: Northern Natural Gas Company Project: Cedar Station Upgrade Project Spread/Loop/Facility: Pipeline Loop Photo No.: 1 Sta. No.: Direction: West Assessment: Problem Area Comments: Residential/Commercial Area. The hay bales were not effective as erosion control devices in the travel lane to keep silt-laden water from leaving the ROW. Northern was asked to replace the entrance with rock or other measure to prevent or minimize future silt-laden stormwater from leaving the ROW. Photo No.: 2 Sta. No.: Direction: West Comments: Residential area. Secondary containment was installed around the drilling equipment and frac tanks. Orange safety fence was installed along the adjacent ROW. No problems noted. 6

7 PHOTOGRAPHIC RECORD Company: Northern Natural Gas Company Project: Cedar Station Upgrade Project Spread/Loop/Facility: Pipeline Loop Photo No.: 3 Sta. No.: Direction: West Comments: Residential area/utility ROW. Highline trail was relocated along this section of ROW. Topsoil was stable with temporary vegetation growth. Orange safety fencing was installed adjacent to residences. No problems noted Photo No: 4 Sta. No.: Direction: East Comments: Forested area. Lebanon Hills Regional Park. A sinkhole developed during drilling. Northern indicated it would test, grout, and then backfill in this area. The sinkhole was fenced with orange safety fencing because of its depth. 7

8 PHOTOGRAPHIC RECORD Company: Northern Natural Gas Company Project: Cedar Station Upgrade Project Spread/Loop/Facility: Pipeline Loop Photo No.: 5 Sta. No.: Direction: West Comments: Interlachen Drive. The road was kept mud-free. Orange safety fence was installed adjacent to the residential areas. No problems noted. Photo No.: 6 Sta. No.: Direction: West Comments: Forested area/meadow/buck Pond. Heavy rain occurred during the inspection and pooled at the silt fence. A pump was installed to move the water to a frac tank to prevent it from entering Buck Pond. Double layered silt fence was installed in this area. The pump was in secondary containment. No problems were noted. 8

9 PHOTOGRAPHIC RECORD Company: Northern Natural Gas Company Project: Cedar Station Upgrade Project Spread/Loop/Facility: Pipeline Loop Photo No.: 7 Sta. No.: Direction: East Comments: Wetland W-24. The inadvertent return that occurred on June 17 was cleaned. No residual drilling mud was noted. Although mud entered the wetland, it did not appear that it entered the open water of this wetland. Photo No.: 8 Sta. No.: Direction: East Comments: Upland adjacent to Wetland W-24. The environmental crew was cleaning up the inadvertent return that occurred on the day prior to the inspection. A hydrovac truck was parked within the drill site and mud was vacuumed out. No problems noted. 9

10 PHOTOGRAPHIC RECORD Company: Northern Natural Gas Company Project: Cedar Station Upgrade Project Spread/Loop/Facility: Pipeline Loop Photo No.: 9 Sta. No.: Direction: South Comments: Open area. The drill pad for the entry into Lebanon Hills Regional Park. Activity at the site was minimal. Topsoil piles were seeded with oats and stable, and erosion controls were installed around the perimeter of the site. No problems noted. Photo No.: 10 Sta. No.: Direction: East southeast Comments: Wetland W-07. Northern had stripped the topsoil from the wetland and matted the area for the HDD #2 pullback pipe. Eventually the mats will be removed and Northern will install the pipeline using the open trench method across the wetland. The second set of mats are the travel lane. Silt fence was installed and functional at the edge of the right-of-way. 10

11 Document Content(s) CP Cedar Station Inspection PDF