Letter: The wisdom of treating Waughop Lake with alum needs to be questioned

Submitted by Don Russell, Lakewood.

Lakewood’s $200,000 Brown & Caldwell Waughop Lake Management Plan recognized that Waughop Lake’s toxic algae blooms are the result of 65 years of Western State Hospital discharging slaughtered animal waste, manure and human sewage and 40 years of Pierce College intermittently discharging human sewage into Waughop Lake.

The Plan stated that the appropriate action to mitigate the effect of these discharges is to remove the nutrient rich layer of sediment that has built up on the bottom of the lake as a result of these discharges. B&C assigned a $2.7 to $17.9 million cost estimate to remove this layer of nutrient polluted sediment “depending on disposal and treatment requirements”.

The Plan also indicated that the phosphorus contained in the water column and 10 cm of bottom sediment could be inactivated by a $210,000 lake-wide alum treatment. Such a treatment would likely prevent harmful Cyanobacteria blooms from occurring in the lake for from 3 to 5 years, after which ongoing repeated alum treatments would be necessary until the lake fills in as a result of these alum treatments and becomes a hydrogen sulfide emitting marsh.

What the Plan did not indicate was that an alum treatment would pollute Waughop Lake’s bottom sediments with aluminum hydroxide and a variety of toxic sulfur compounds (sulfates, sulfites, sulfides). The existence of these pollutants will not only negate the commercial value of Waughop Lake’s nutrient rich sediment as a soil amendment material, it will significantly increase the cost of any future sediment removal and disposal operation.

No effort was made by City staff to explore how the lake’s nutrient rich layer of sediment could be removed for $2.7 million. No request for State funding to remove the layer of nutrient rich sediment laid down by the discharges of two State owned institutions was made. No opportunity was afforded the public to be involved and participate in considering various sediment removal and/or treatment options.

Instead City staff recommended that Council approve the alum treatment option. Not satisfied with Brown & Caldwell’s cost estimates the City staff requested a second opinion from Harry Gibbons of TetraTech. TetraTech came back with dredging cost estimates of from $7.9 to $31.6 million and an alum treatment estimated cost of $780,000.

It appears that the City, in spite of all of the above, is determined to proceed with a local rate payer funded expensive and environmentally questionable alum treatment of Waughop Lake.

It is important to consider the ramifications of the City’s action.

Brown & Caldwell’s proposed alum treatment will involve the tank truck delivery of 20,000 gallons of liquid aluminum sulfate and 10,000 gallons of liquid sodium aluminate weighing a total of 343,000 pounds to the shoreline of Waughop Lake. This delivery will require 8 tank trucks weighing close to 80,000 pounds each traveling over the park’s roadway and onto the pedestrian trail. TetraTech’s alum treatment proposal more than doubles (2.3 times) the material prescribed by B&C. Such a treatment would require 18 80,000 pound gross weight tank truck deliveries of liquid aluminum sulfate and sodium aluminate to the shoreline of Waughop Lake.

Under B&C’s proposal 343,000 pounds of delivered liquid material will then be transferred to a large specialized barge and discharged into Waughop Lake. The barge and its tractor trailer rig will come from the upper Midwest since there is no local provider of such equipment. Upon its arrival the barge will be launched into and retrieved from the lake over the fragile edge of the pedestrian trail since there is no boat launch ramp available on the lake.

One has to ask whether or not the park’s roadway and pedestrian trail was designed to handle this much weight and tank truck traffic and barge launching and recovery operation.

By contrast an annual application of an Ecology approved herbicide (to control aquatic plant growth), an algaecide (to prevent nuisance green algae blooms) and approximately 1,500 pounds of finely granulated iron powder (to prevent harmful Cyanobacteria blooms by inactivating phosphorus in the water column) delivered by a pickup truck towing a light weigh trailer and portable barge having a combined weigh of less than 10,000 pounds for a cost of from $50,000 to $75,000 per year is a real and environmentally sound bargain compared to Brown & Caldwell’s estimated cost of $210,000 and TetraTech’s $780,000 estimated cost for an alum treatment.

Furthermore such a light application of Ecology approved chemicals by an Ecology licensed local applicator would not aluminum hydroxide and sulfur compound pollute Waughop’s bottom sediments. Such a light annual Ecology permitted combination chemical application would control the lake’s excessive plant growth and prevent nuisance filamentous green algae and harmful Cyanobacteria blooms and preserve the value of the lake’s nutrient rich bottom sediments as a soil amendment material until such time that State money becomes available to fund a $2.7 million removal of the nutrient rich layer of sediment that exists as a result of past discharges of polluted material from two State owned institutions.

Editor’s Note: Read Don’s prior two letters on the topic:

• Letter: Lakewood City Council condones City staff’s nonfeasance (March 1)
• 2nd Letter: Lakewood City Council condones City staff’s nonfeasance (March 7).