County Concrete's Black River Restoration Plan - What isn't Said

by Brian Lynch

I had a chance to review the County Concrete plan to restore the Black River, a noble idea on its face.

The Upper Black River before it flows into Sunset Lake

First, the idea of restoring the Black River to its original condition (with natural vegetation of course) has merit. The concept of reconnecting the upper and lower reaches of the Black River and restoring it to its natural state is a fantastic prospect. The plan as presented in the application appears to be okay and fairly complete as far as the river goes. Some technical discussions and terms are beyond me. An independent scientific review of the plans is needed.

What I didn't see in the application was a comprehensive testing plan of the proposed fill material to be certain it doesn't contain any contaminants. I would like some assurances that the fill material won't be mixed with concrete kiln dust (CKD) or other materials containing constituents that can cause health problems.

Cement manufacturing, in general, is a high pollution industry but also a vital industry. The cement sector is the third largest industrial source of pollution, emitting more than 500,000 tons of sulfur dioxide, nitrogen oxide, and carbon monoxide per year. The main pollutants from cement production include; cement dust, air pollution, water pollution, solid waste pollution, noise pollution, ground vibration, and resource depletion due to raw material extraction. There are technologies, processes, and regulations to help reduce the negative environmental impacts of cement production while keeping the industry economically viable. We rely on the NJ DEP and the goodwill of County Concrete to strike an equitable balance. 

The next question is, where is all this fill material coming from? It most likely didn't originate from Sunset Lake as the "legacy" fill described in the application. I know of no sand mining operation at Sunset Lake in the 40 years I've lived in town. If the fill material in question is the same material piled above the vegetation line seen from the north shore, it is being brought in from elsewhere.  I've seen that pile rapidly accumulate for several years now. I suspect it comes from their very active quarry on W. Dewey Avenue. There may still be a sand quarry operation at Kenvil Lake to the North, but the material being shipped into the plant is dry, not wet. County Concrete tandem dump trucks ship material into the plant all day long. 

Then there is the bigger question not addressed by the application. What is to become of Sunset Lake? 

Northern end of Sunset Lake from Mine Hill Beach

This former sandpit is today an ecologically productive and recreationally active lake. Recreational activities include fishing, swimming, and boating. To the best of my knowledge, the ecology of Sunset Lake has not been scientifically studied, but it obviously supports a large variety of aquatic plants and animals. 

The lake has three main water sources, the "Lamington" tributary in the Northeast, which originates at the spring along Canfield Avenue; the Black River in the Northwest that originates on the former Hercules Powder property; and the general flow of groundwater through the sand that travels in a North to South direction. The volume of groundwater that flows into the lake is undetermined. Of the two surface water inlets, the Black River supplies perhaps ten times more volume of water. It is likely that some of the surface water in the upper Black River also filters into Chesler Lake, so the exact volume of water it contributes to Sunset Lake is undetermined.

Sunset Lake has three outlets. A spillway at the lake's southern end rejoins the Black River north of Black River Pond. The Black River itself reforms by infiltrating a sandy channel that runs along the southwest shore of Sunset Lake. It is separated from the lake by a narrow, heavily vegetated sandbar. This sandbar is essential to filter out most of the suspended solids introduced into the Lake by the concrete plant operations. On the other hand, the spillway introduces some turbidity into the water entering Black River Pond. This is evident in surface water coloration differences seen in aerial photographs. The third outlet is by general filtration through the sand, including infiltration into Randolph Pond, which has no surface inlets or outlets and little turbidity. 

Sunset Lake supplies County Concrete with the water needed for plant operations.  An unknown amount of water is pumped from Sunset Lake daily, and operational wastewater with a high concentration of suspended solids is discharged back into the lake during plant operations. The County Concrete application states that Sunset Lake's shallowness raises water temperatures in the Black River, reducing oxygen levels. The application does not mention the impact of warm wastewater temperatures and increased turbidity on the lake during plant operations. Wastewater from the plant first passes through three shallow, narrow, and very turbid settling ponds exposed to direct sunlight during the day. This discharge must certainly raise the temperature of the lake. 

The three settling ponds are apparently inadequate in size and volume to meet their purpose of reducing suspended solids. The exceedances of turbid effluent resulted in County Concrete being cited by the DEP several years ago. County Concrete dredged the settling ponds (increase their volume) to lower the concentration of particulates. I see little visual evidence from satellite images that this made a significant difference. In the meantime, the water entering the lake from Mine Hill has a high classification for protection by the DEP. This probably increases the regulatory hurdles County Concrete faces in discharging its wastewater.  

The Black River Restoration plan proposes reconnecting the upper and lower Black River without discharging into Sunset Lake. If I am reading this correctly, the plan also connects the Lamington Tributary with the Black River at the lake's northern end. Creating these new channels would involve filling in a large volume of the lake and reducing the lake's surface area by over eight acres. The plan also appears to eliminate the spillway at the lake's southern end. This would lower the lake's total volume while eliminating all the surface water inlets and outlets. Sunset Lake would become a very large settling pond with exceptionally high levels of suspended solids and even warmer temperatures. Allowing the Lamington Tributary to bypass the lake eliminates some of the regulatory burdens on the company. 

Lamington Tributary 

 I fear that the lake's ecology under this plan would most likely be severely impacted. Very high levels of suspended solids and higher temperatures could result in uninhabitable conditions for aquatic plants and animals.  Swimming and other recreational activity on the lake might cease. 

 Is this an acceptable balance? Are there other possible planning options that might preserve an ecologically viable portion of Sunset Lake? 

 For example, what if the Mine Hill section of the lake were to be isolated from the County Concrete section by a sand bar running along the County Concrete property line and allowing the Lamington tributary to continue flowing into the Mine Hill Lake? The spring feed lake could then reconnect with the Black River at the southern end of the property as it does now, but without the suspended solids it carries. 

Shouldn't an environmental impact study be conducted on the lake to help answer these sorts of questions? Given environmental changes to our weather patterns, conserving as much fresh water as possible is imperative in the months and years ahead. If County Concrete can get by without despoiling the entire lake, that should be everyone's goal. 

Please note: This is all my personal opinion based on my review of the application, my personal observations, and what I have come to learn in my own research. We must wait for expert analysis by actual scientists for a more definitive assessment.