On Point newsletter for April 2015

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On Point - News and updates for wastewater discharge permit holders

April 2015

St. Cloud wastewater project

The project team for the Nutrient Recovery pilot at the St. Cloud  Wastewater Treatment Facility included, from left, Shane Lund, Brian Schoenecker, Erin McMahon, Tracy Hodel, Lisa Vollbrecht, Emma Larson, Wayne Ethen, Patrick Shea and Scott Schaefer (AE2S). (Photo courtesy of St. Cloud WWTF) 

St. Cloud pilot project: Harvesting phosphorus from a wastewater side stream for fertilizer

St. Cloud wastewater treatment plant

Harvesting phosphorus for fertilizer from a wastewater side stream shows promise according to a recent pilot project at the St. Cloud Wastewater Treatment Facility (photo at right).

The facility receives 10 million gallons a day of wastewater from the cities of St. Cloud, St. Joseph, Sartell, Waite Park, Sauk Rapids and St. Augusta. It received a Clean Water, Land and Legacy grant to test nutrient recovery, an emerging technology in wastewater treatment.

Harvesting nutrients offers several benefits, including:

  • Removing a form of phosphorus that can lead to problems in the treatment process. Magnesium ammonium phosphate – also called struvite – can cause significant operational issues when precipitation is uncontrolled.
  • Achieving nutrient limits to help lakes and rivers. Removing the phosphorus can help treatment plants reduce the nutrient level in their discharge to surface waters where phosphorus can cause algal blooms.
  • Meeting the demand for farm fertilizers. Harvesting the phosphorus for fertilizers helps agriculture because the world is depleting its available amount of phosphorus.

For the pilot project, the city of St. Cloud and its consultant, Advanced Engineering and Environmental Services (AE2S), tested harvesting struvite from the biosolids supernatant to help maintain effluent phosphorus at the current concentration of 0.3 mg/L. After trial and error, the project team used a precipitation process to harvest useable phosphorus from the biosolids supernatant. The project showed that struvite can be harvested from biosolids waste streams with some modifications to the waste streams.

For additional information about this project please contact Bruce Henningsgaard at the MPCA at 651-757-2427 or bruce.henningsgaard@state.mn.us, or Emma Larson at the city of St. Cloud at 320-255-7226 or emma.larson@ci.stcloud.mn.us.

The pilot project will also be the subject of a Mississippi River Forum. "No such thing as wastewater: St. Cloud's innovations in resource recovery," will be presented on Friday, April 24 from 8-9:30 a.m. in St. Cloud and Friday, June 19 from 8-9:30 a.m. in Minneapolis. See the forum webpage for more information. 

eDMR news

MPCA working to resolve calculator inaccuracies


Based on comments from permit holders and from MPCA enforcement staff, the agency has found that its eDMR calculations are not always accurate. It appears that maximum calendar week average values for CBOD and TSS may sometimes be calculated incorrectly, especially for permits that require twice-per-month sampling. There may be problems with other maximum calculations too.

Because the problems occur randomly, they require more investigation to resolve. MPCA’s priority at this time is testing and preparing the new eDMR and calculator services. Because of this priority, corrections to existing services may take additional time.

Until the MPCA announces that the existing calculations are fixed, the agency urges you to review the results of all MPCA calculations to ensure you report valid numbers on your eDMR. Also, be sure to look at the calculated values to ensure they make sense. For example, if the pH is calculated as 20, that can’t be correct.

New sampling requirement for MNG490000 non-metallic mining permit holders

Entities with permits for non-metallic mining should be aware of new sampling requirements if they have dewatering discharges. For parties with coverage under the MNG490000 Nonmetallic Mining and Associated Activities General Permit, the 2016 permit reissuance process will require additional monitoring data of dewatering discharges.

The sampling and analysis of additional parameters is required prior to permit expiration and should be submitted with application for permit re-issuance.  Permit applications for the next reissuance will be due May 4, 2016.  Because the application deadline is in late spring, sampling and analysis of dewatering discharges may be difficult depending on weather conditions. The MPCA advises doing the additional dewatering monitoring requirements this year. 

Applications submitted without this required monitoring data will be considered incomplete.  Please see part 8.20, page 20, of the MNG490000 permit for the specific list of parameters and other details. 

If you have any questions, please contact Theresa Haugen at theresa.haugen@state.mn.us or 218-316-3920.

Wastewater conference: Thank you to participants, congrats to award recipients

The MPCA thanks all the presenters and 600-plus attendees at the 78th annual Wastewater Operations Conference March 25-27 in Brooklyn Park.

Congratulations to the 120-some Wastewater Treatment Facilities that received Operational Awards for outstanding operation, maintenance and management practices at their facilities in 2014. And congratulations to the operators who received the awards on their facility’s behalf. The awards are based on a facility demonstrating full compliance with MPCA operating permits. They also require that facilities are overseen by properly certified operators; all required monthly and annual reports are timely and properly completed; and facilities have no unauthorized releases or bypasses, enforcement actions or inspections identifying compliance issues.

Look for the list of winners to be posted soon on the MPCA website.

MCES - Empire WWTF taking the initiative to sustain environment

Nominees for Environmental Initiative Awards include a sustainability project at the Empire Wastewater Treatment Plant - Metropolitan Council Environmental Services (MCES) on the Vermillion River in theTwin Cities metro area.

Thanks to partners and volunteers, the project included, according to the Environmental Initiative:

  • Stabilizing 1,200 feet of severely eroded streambank;
  • Installing “lunker boxes” in a stream to provide trout habitat;
  • Restoring a 50-acre wet meadow wetland;
  • Removing invasive buckthorn vegetation from the floodplain; and
  • Enhancing species and plant diversity in a 34-acre grassland.
Start of streambank restoration at Empire WWTF

In addition, when the MCES-Empire WWTP expanded from 2004 to 2007, the facility relocated its effluent conveyance pipe to divert treated wastewater from the environmentally sensitive Vermillion River. The expansion also included many low impact development improvements designed to achieve zero runoff in rainfall events:

  • A green roof;
  • Permeable pavers;
  • Infiltration basins; and
  • Recycling treated wastewater for use in other WWTP processes.
Streambank during restoration at Empire WWTF
Streambank fully restored at Empire WWTF

The project has resulted in increased diversity of birds and other wildlife at the site, improved water quality and presence of fish in the state-designated trout stream, and achievement of zero runoff after rainfalls of up to 5 inches contributing to replenishment of groundwater resources.

For more information, read about the project on the Environmental Initiative website.

Top photo: Streambank at start of stabilization. Middle photo: Streambank during the restoration work. Bottom photo: Fully restored streambank flourishing with plants. Photos courtesy of Karen Schik/Friends of the Mississippi River

In the news and online: Wipes, recycling and nitrate costs

“ 'Flushable' wipes can cost thousands to fix clogged pipes” in the StarTribune

“San Francisco plan requires new buildings to recycle water” in the Pioneer Press

“A drop in the bucket, a hit to the wallet” in the Duluth News Tribune

“Water Works winter nitrate costs: $540,000” in the Des Moines Register

“For the love of water, become a volunteer monitor today” on the MPCA website

Governor’s Jobs Bill Would Create 23,900 Minnesota Jobs ” (includes $21.6 million for wastewater infrastructure projects in Tracy, Grove City, Clarissa, Wauburn, Brownton, Hoffman, Lakefield, and other communities around the state) on the Gov. Mark Dayton website