Meghan Litsey, Director of Environmental Compliance, WSB

Minnesota has experienced drought before, but this year is unique. Drought conditions began earlier than normal and are anticipated to continue through October. Despite recent rainfall, it will take much more precipitation to ease drought impacts as we head into fall. Although drought has major impacts on many facets of municipal infrastructure, it can also have many impacts on ongoing construction projects.

NPDES Construction Stormwater Permit impacts

Vegetation is key to closing out any ongoing project. As construction season begins to come to an end and projects begin close-out activities, the ongoing drought presents several challenges. The NPDES Construction Stormwater General Permit requires permanent uniform perennial vegetation with a density of 70% of its final growth. Given the challenging conditions this year, some projects may need to consider delaying permanent seeding until conditions improve. 

Alternatives to consider

Rather than applying permanent seed mixtures and risking failure, waiting until conditions improve is worth considering. Another option to think about is dormant seeding. Dormant seeding can be an effective method of maximizing growth in the spring, especially when native species are involved.

Five ways to stay in compliance

1. Always be ready for the next rain event. Continue to install and maintain erosion and sediment control best practices and stabilize exposed soils within permit timeframes.
2. Control dust with water or chemical application, as needed.
3. If delaying permanent seeding, use stabilization placeholders, such as straw mulch, erosion control blanket, or hydraulic mulch, to cover exposed soils until permanent turf can be completed.
4. Continue to perform weed control to prevent excessive weed growth. This may include tilling, mowing, and/or herbicide applications.
5. If permanent vegetation has been established and there are bare areas that need to be supplemented, use interseeding and overseeding to obtain uniform coverage.

Although vegetation may be minimized when looking at a project’s big picture, it has considerable impacts on stormwater runoff. The U.S. Environmental Protection Agency estimates that 20 to 150 tons of soil per acres are lost every year to stormwater runoff from construction sites. The NPDES Construction Stormwater General Permit monitors stormwater runoff during and after construction, protecting many of Minnesota’s natural and water resources. Establishing quality vegetation, even during a drought, can be a challenging feat but is necessary to maintain compliance and protect our water resources.

Meghan Litsey is director of our Environmental Compliance team and has over eight years of experience. She specializes in providing environmental compliance services in construction site permitting, SWPPP design and inspection, and MS4 program development. 

[email protected] | 763.287.7155

By Meghan Litsey, Director of Environmental Compliance, WSB

The countdown to the release of the updated MS4 Permit has begun. The current MS4 Permit expired on July 31, 2018 and the MPCA is tentatively planning to reissue the updated Permit before the end of this year.

As a new permit approaches, take a few minutes to reflect on the progress you’ve made towards meeting your measurable goals over the last five years. We’ve developed procedures, adopted ordinances, formed partnerships, inspected and eliminated illicit discharges, monitored construction sites, and assessed our ponds…and now it is time to start thinking about the next permit cycle.

Soon we will work through the Part II application that outlines how our MS4 programs will come into compliance with the updated MS4 Permit requirements. Before the new MS4 Permit is released, there are some important to-dos to help you get organized before the permit arrives.

Here’s what you can do now:

1. Review and update your storm sewer system map. Take a close look at storm sewer, pond, outfall, and structural stormwater BMP locations and ownership information and complete updates, as needed.
2. Dust off ordinances, written procedures, enforcement response procedures, form templates, and save them in a convenient location – they’ll come in hand for the Part II application.
3. Complete a mock audit. By understanding the current state of your program compared to the existing requirements, you’ll be ready to fill in the blanks in the Part II application with ease. As a bonus, this activity will also help you start preparing for the 2020 MS4 Annual Report; a bit of preparation this fall will save hours of agony in June.
4. Organize your files and recordkeeping mechanisms. Consider creating a shared drive so everyone on your team can help track and contribute to MS4 activities. If your current set-up isn’t working, now is the time to find a system that works for easy tracking for the next permit cycle.
5. Continue the routine upkeep of your MS4 program to keep operations running smoothly, including staff training, erosion control inspections and enforcement, public education efforts, annual meeting, etc. The permit may be expired, but we must continue to implement our programs and ultimately manage our stormwater conveyance systems.   

Start checking things off your list, and in no time at all, you’ll be ready to take-on whatever the new MS4 Permit has in store.

Meghan Litsey is director of our Environmental Compliance team and has over eight years of experience. She specializes in providing environmental compliance services in construction site permitting, SWPPP design and inspection, and MS4 program development. 

[email protected] | 763.287.7155

Soon Minnesota’s Municipal Separate Storm Sewer System (MS4) communities will continue the reissuing process and applying for coverage under the revised MS4 General Permit. The updated MS4 General Permit is expected to be reissued by the Minnesota Pollution Control Agency (MPCA) this Summer of 2020. This will create significant changes in the ways that MS4 permittees will operate, starting with modifications to address any procedural and programmatic changes needed as a result of the updated rules.

Below are the Top 5 Proposed Changes – What You Need to Know

1. Volume control requirements to treat all new and fully reconstructed impervious surfaces equal to one or more acres.
2. New performance-based responses to chloride, bacteria, and temperature TMDLs; including a written plan to identify and prioritize activities to achieve reductions.
3. Additional education and outreach efforts on salt use and pet waste.
4. Increased responses to snow and ice control operations. Improved management of salt storage at commercial, institutional and non-NPDES permitted industrial facilities.
5. Additional documentation requirements to better evaluate permit compliance and SWPPP effectiveness.

The MS4 permit application process is a two-part process. The first includes the permit application fee, contact information for the applicant, and applicant certification. Existing permittees have already completed this step in late 2017 or early 2018. The second part, known as the Part II Stormwater Pollution Prevention Program (SWPPP) Reauthorization Application document, includes information about the applicant’s current SWPPP. It compares it to the revised permit rules and identifies action permittees will take to be compliant with the updated MS4 rules.

Once the MS4 permit is reissued by the MPCA, there will be a 5-month (150 days) period for applicants to submit an application electronically through the MPCA’s website to the MPCA Commissioner for review. After permit applications have been approved by the MPCA, the new SWPPP document will be placed on public notice for 30 days with the opportunity for a hearing on the preliminary determination. Following the public notice, permittees will have 12 months to update their MS4 programs to meet the new permit requirements. Our Environmental Compliance group is familiar with every step of this MS4 permit reissuance period and available to assist.

In the meantime, MS4s must continue to implement their programs and follow the expired MS4 permit’s rules. This means that routine efforts to provide education and training, identify illicit discharges, and monitor and maintain the MS4 system must continue. MS4 permittees are also expected to continue their erosion control inspection schedules and monitor active construction projects despite the COVID-19 pandemic. Inspectors are encouraged to wear masks and maintain social distancing standards while out on site. Our Environmental Compliance team is available to help your community meet this permit requirement. We can help augment site audits by regulators, provide temporary inspection support, carry out enforcement protocol, and provide any other support to help local erosion control programs.

Please contact us for additional assistance or questions.

Meghan Litsey is director of our Environmental Compliance team and has over eight years of experience. She specializes in providing environmental compliance services in construction site permitting, SWPPP design and inspection, and MS4 program development. 

[email protected] | 763.287.7155

By Meghan Litsey, Sr. Environmental Scientist, WSB

Municipal Separate Storm Sewer System (MS4) communities tend to dread the words “compliance audit”. The auditing process can be intimidating, but it can also provide an opportunity to highlight positive aspects of your community. Local agencies like the Minnesota Pollution Control Agency (MPCA) can offer insight about the process and help generate ideas for your MS4 program. Right now, the MPCA is conducting regular compliance audits despite the new MS4 permitting that is anticipated to take effect later this year.

So, it’s important to keep your MS4 program up to standard and audit-proof all year round.

Why does the MPCA perform audits?

The MPCA performs audits on MS4 programs per the Environmental Protection Agency (EPA). The EPA requires routine audits to evaluate permittees for program compliance, best management practices, and identified performance goals. To meet this mandate, the MPCA has committed to completing approximately 33 MS4 program audits per year to ensure a timely and proper evaluation of each permittee.

Getting ready for an MS4 audit?

Try these tips to keep your MS4 program audit-proof.

1. Conduct a mock audit. Use guidance documents from the MPCA and EPA to conduct a mock audit. Now is the time to identify potential areas of improvement before you’re faced with an actual MS4 audit.
2. Plan ahead. Create a 12-month schedule for specific requirements to stay on track. For example, you should schedule MS4 inspection and training dates well in advance. You may also want to include publication deadlines to ensure any article submissions are delivered on time.
3. Document everything. Documentation is your best ally in an audit scenario. Find a recordkeeping system that works and stick to it. And be sure to take credit for your work.
4. Partner up. Why recreate the wheel? Consider partnering with other MS4s or local groups and share permit responsibilities. Otherwise, you can also utilize existing partnerships and discuss sharing responsibilities.
5. Invest in your staff. Field staff are the first line of defense when it comes to protecting your MS4 system from illicit discharges. Ensure all field staff, including seasonal and contracted staff, are trained on the importance of their role in protecting water quality.

Meghan Litsey is a Senior Environmental Scientist on our environmental team with over eight years of experience. She specializes in providing environmental compliance services in construction site permitting, SWPPP design and inspection, and MS4 program development. 

When people think of slope failure or geohazards, they think of landslides and mudslides in mountainous regions like California. Those of us living in the Midwest don’t typically worry about property damage or disruptions in public services due to slope failure. Unfortunately, slope failure impacts a wide range of landscapes, even those considered relatively level. In fact, in the Twin Cities there have been increasing numbers of slope failures that significantly impacted infrastructure and property. The most recognizable example is probably the 2014 slope failure along the West River Parkway in Minneapolis. This slope failed after more than 11 inches of rain fell in two days, impacting a popular recreational trail as well as a major health care facility. Repairs were completed in 2016, and cost $5.639 million [i].

Slope failure is a geohazard that impacts many types of infrastructure, from individual homes to municipal storm sewer networks to oil and gas pipelines. In fact, the Pipeline and Hazardous Materials Safety Administration requires that natural gas and hazardous liquids pipelines develop risk assessment programs for slope failures in their systems. Likewise, many municipalities are beginning to incorporate these types of risk assessment programs into their own planning activities.

So what causes slope failures? Like all geohazards, the causes are myriad and complex. Establishing a framework of how the physical processes behind slope instability function is crucial in determining risk.
Simply put, slope stability is based on the interaction of two forces: driving forces and resisting forces. Slope failures occur when driving forces overcome resisting forces. The driving force is typically gravity, and the resisting force is the slope material’s shear strength.

When assessing a slope’s stability look for indications that physical processes are decreasing shear strength. These can include:

• Weathered geology: Weak, weathered bedrock, jointed rock, or bedrock that dips parallel to the slope can decrease stability.
• Vegetation removal: Droughts, wildfires and humans can remove vegetation from the slope, decreasing stability.
• Freeze/thaw cycles: Water in rock joints or in soils can decrease slope stability.
• Stream action: Rivers can erode the bottom of the slope, called the toe, decreasing stability. This can occur over time through normal stream action or catastrophically during flood events.
• Human modifications: Humans modify stability through actions such as excavation of the slope or its toe, loading of the slope or crest, surface or groundwater manipulation, irrigation, and mining.
• Slope angle: Steeper slopes tend to have greater risks for instability.
• Soil type: Soils have variable amounts of shear strength, dependent on factors such as soil texture, pore water, and particle cohesion.
• Water sources: Water works in many ways to reduce shear strength. For example, pore water pressure in soils decreases shear strength, and saturated soils are more likely to lead to slope failure. Perched water tables, groundwater seeps, and excessive precipitation are some examples of water sources that may lead to slope failure in certain conditions.

Many things can impact the stability of a slope. Just like with stream crossings, all geomorphic factors affecting slope stability should be considered when determining the risk of slope failure.
After the geomorphic factors for each slope crossing have been adequately assessed, these indicators can be fed into our geomorphic framework of slope stability to determine how likely slope failure is at a particular location.

An example of a risk matrix developed for slope stability is below. This matrix is determining the likelihood that a slope failure will occur and multiplying that by a known consequence to derive a risk factor (from the formula above). For this type of risk matrix to work, robust rational and consequence definitions should be developed to support the risk estimation. In this example, geomorphic analyses have resulted in a specific set of justifications for the likelihood of slope instability. These categories are then assigned risk factors. Very Low stability slopes, as defined by the rational in the matrix, have an Almost Certain (5) risk factor.

Detailed definitions have also been determined for the Failure at Road consequence, and those definitions are assigned risk factors. A slope failure at a road is considered Critical (5) if the road is a critical evacuation route, major transportation corridor, or restricts access to emergency facilities. Almost Certain (5) slope failures at Critical (5) roads have a Risk Factor of 25 and require mitigation.

While this example matrix only lists one consequence category (Failure at Road), a risk matrix can be designed to include as many consequences as necessary to capture the complete risk profile. Additionally, the application of five risk factors is merely an example. Risk matrices can be designed with as many or as few risk factor categories as necessary.

The outcome of this analysis is a set of risk factors that pipeline operators, city planners, engineers, or transportation officials can use to prioritize capital spending in a non-biased way, proactively estimate capital budget, manage interim risks, and more accurately estimate maintenance budgets.

[i] https://www.minneapolisparks.org/_asset/hwlxv3/west_river_parkway_faq.pdf
Photo: http://www.windomdam.com/CSS/2008-11-18%20Letter%20to%20City%20Responding%20to%20the%20SEH%20Feasibility%20Report.htm