Earlier this year, masses of dead fish showed up on Kekaha’s popular surf beaches. It was not the first time and certainly not the last. When the area was still a sugar town, dead fish would turn up on the beaches two to four times a year, according to one longtime resident.
The sugar plantation has closed, but some in the community have noticed an increase in the frequency and number of fish kills since a big shrimp farm made its home in the quiet, rural town in the late 1990s. Some believe there is a connection. While one has not been proven, their suspicions are not unfounded.
Thomas Crocker, who leases land adjacent to the farm, says of the episode this year, dead fish littered the coast “all the way from my property to the housing gate at the naval base, past the bird sanctuary to where two ditches converge, piled up along Major’s Bay.”
On a small, state-owned lot, where the long stretch of beach along Kaua`i’s Highway 50 merges with a long stretch of agricultural land, sits the little Sunkiss Shrimp Farm, with a tan circus tent-like building, a few round ponds with paddle wheels, and a few pick-up trucks parked in front of a small office building. Despite it’s name, Sunkiss is not actually a shrimp farm, but a hatchery for its parent company down the road, CEATECH USA, Inc.
Observing from the highway, one might not notice a 140-acre shrimp farm, capable of producing 1.6 million pounds of shrimp a year, is even there. Fields of corn and sugar line the road, and posted signs announce the Naval base (the Pacific Missile Range Facility) and the endangered bird refuge that share the long strip of coastal land with CEATECH. But while some of CEATECH’s ponds sit along the highway, raised, overgrown berms obscure them; the rest are hidden behind a wall of trees.
Almost no one who isn’t a CEATECH employee gets past the company’s locked front gate. Don Heacock of the state Division of Aquatic Resources says that CEATECH has refused every request he or members of the Soil and Water Conservation District have made to visit the farm.
Add to this secrecy an apparent increase in shark sightings and fish kills since CEATECH moved in and it helps explain why many members of Kaua`i’s west side are angry and point to CEATECH for a lot of the changes they see in the coastal waters.
Rhoda Libre, head of Kaua`i’s Westside Watershed Council, says that while the agricultural plain’s ditch sometimes receives sewage effluent, that waste alone isn’t suffocating the fish. “CEATECH blames the sewage. Both are at fault.” She says that the shrimp farm dumps its waste into the ditch and into a pond where a sand bar blocks it in. There, “The effluent seeps underneath, it still goes into the ocean, but it stands stagnant and there are dead animals all over the place.”
Like Kekaha’s coastal waters after a rain, CEATECH’s operation seems especially murky, particularly in the way it deals with its contribution to the agricultural plain’s waste stream.
Since the late 1990s, CEATECH, USA, Inc. has added increasing amounts of effluent to the area’s drainage system. When it was just starting up, it’s representatives testified that it was going to be unlike any farm Hawai`i’s shrimp industry had ever seen.
In the traditional hectare-large rectangular ponds used on O`ahu, shrimp were crowded together along with algae, bacteria, their feces, molts and uneaten food, a situation that eventually killed the shrimp or inhibited their growth. One after another shrimp farm in Hawai`i failed under this type of system.
When CEATECH started it proudly described its super-efficient waste collection system: water would swirl in round, sloped one-acre-ponds, pushing waste material into a center drain, where it would be easily removed and give the shrimp a cleaner, more stress-free environment.
CEATECH’s wastewater would be treated in a settling basin where solids were removed before discharge into the ocean. The recovered solids would be used as an agricultural soil amendment.
These innovations seemed promising and when CEATECH applied for its National Pollutant Discharge Elimination System (NPDES) permit in 1998, it drew some impressive supporters: university professors, Kaua`i mayor Maryanne Kusaka, and head of the state Department of Agriculture James Nakatani. Nine others, many of them heads of Kaua`i business associations, offered their support, most of them noting CEATECH’s genuine concern for the environment and Kaua`i’s residents.
Over the years, CEATECH has nearly filled the state Department of Agriculture’s 156-acre Kekaha Agricultural Park with these ponds. Each of its 40 ponds produces about 40,000 pounds of shrimp a year, their waste dumped into the Kawaiele channel that bypasses the farm.
For the last two years, discharge from CEATECH’s shrimp farm has consistently exceeded levels of nitrogen and ammonia nitrogen allowed by the company’s NPDES permit, which allows a maximum daily level of nitrogen of 1725 ug/L, and 63 ug/L for ammonia nitrogen. High levels of nitrogen in waterways can cause eutrophication and algae blooms that can kill marine fauna.
In March 2000, Mark Tomomitsu of the Clean Water Branch informed CEATECH vice president Paul Bienfang that it was not in compliance with its NPDES permit. Bienfang responded that the elevated levels of ammonia nitrogen and total nitrogen were not dangerous to aquatic life or the environment. “Quite to the contrary, this problem is the result of the excellent aquatic habitat created within the farm infrastructure,” he wrote.
Still, the non-compliance issue needed to be addressed. CEATECH explained that its high levels of nitrogen and ammonia nitrogen were the result of wild tilapia that had gathered at the farm to feast on the nutrient-rich effluent. Tilapia are an introduced species present in many of the state’s waterways, and do excrete large amounts of ammonia.
“This elevated NH4 (ammonia) is caused by the large tilapia population that has become established in the newly created aquatic habitat within the discharged canals and sedimentation basins upstream of the sampling location for effluent leaving the farm. The tilapia population originated from animals that swam up onto the farm from the ‘Suez’ and Kawaiele ditches [part of the greater Kekaha irrigation ditch system]. … These fish have subsequently become established and are breeding in the favorable aquatic habitat within the discharge infrastructure of the CEATECH Plantations farm,” Bienfang wrote.
Bienfang continued that CEATECH would resolve the problem by eradicating or removing the tilapia from the discharge canals and sediment basins within the farm. He wrote that the company expected to receive “several pieces of equipment that we have ordered to support the removal process” in a couple of weeks. He added that “If necessary, we will also supply bacterial augmentations to the canal/basin water to further reduce the NH4 levels.
“We fully expect that removal of the tilapia will mitigate the NH4 level, and that the non-compliance will be corrected by the time of the next comprehensive water quality sampling.”
Not only was the situation not corrected, but during the next sampling, the exceedances had apparently gone beyond the discharge point and into waters within an arc of 6,000 feet radius beyond it called the Zone of Mixing (ZOM).
An undated summary of ammonia reduction efforts by CEATECH indicates that the company tried trapping and netting the fish to reduce ammonia levels, it tried augmenting microbial populations with bacteria that turn NH4 to NO3, it tried increasing levels of dissolved carbohydrate, and installed an aeration device to increase the metabolic rates of aerobic bacteria. Nothing worked.
One of the methods CEATECH tried to control tilapia was to poison them. On August 17, 2000, Bienfang notified the state that CEATECH was harvesting tilapia that week from its discharge canals and basins “following repeated applications of Rotenone.”
Fish poisons such as Rotenone have been used to eradicate tilapia in Australian ponds and small dams, “but are not practical for rivers and streams as these poisons also kill native fish,” according to a Queensland Government web page on tilapia eradication efforts in Australia.
CEATECH’s application of the poison seems to violate a condition in its NPDES permit that states, “No bioactive compounds such as pesticides, antibiotics … shall be applied to the shrimp farm operations and discharged from Outfall Serial No. 001.”
Furthermore, anyone seeking to use rotenone to kill fish must, at the very least, obtain permission from the state Division of Aquatic Resources (DAR). Don Heacock, head of DAR on Kaua`i, was shocked to hear that CEATECH had used rotenone without his ever reviewing an application or request to do so. Echoing the Queensland government’s concerns about the danger of rotenone to native fish, Heacock added, “I guarantee there are baby `ama`ama and awa in March, April and May in that system.”
Francis Oishi, with DAR in Honolulu, also told Environment Hawai`i that permits to use rotenone are usually restricted to research, education, or scientific purposes. Regardless of the use, Oishi said that CEATECH probably should have been required to have permits from the state agriculture and health departments, as well.
Without permits, it seems, CEATECH killed a lot of fish. In an August 2000 fax received by the DOH, Bienfang wrote that “we removed substantial biomass,” and “The effects of the poisoning also appeared to be confined to the farm site proper. We took repeated walks downstreamÉon several days and on no occasion did we see any mortalities – but we did see many active, healthy fish. We are quite confident that the effects were restricted to the farm location proper.”
August 2000 is the only documented use of CEATECH’s rotenone applications. But despite Bienfang’s assurances that the effects were restricted to the farm site, when masses of dead fish started turning up on the beaches and in CEATECH’s canals, fingers began to point to the shrimp farm.
In May 2001, the odor of dead fish was so strong that one of CEATECH’s neighbors complained. A report by DOH inspector Gary Ueunten read, “A strong odor was detected and dead Tilapia were observed in the canal leading from the CEATECH facility to the ocean outfall. Approximately 100 dead Tilapia were floating in the canal.”
For this fish kill, CEATECH did not take the blame. “Landis Ignacio [who runs Sunkiss] … said that the fishkill was caused by low dissolved oxygen in the canal and that this type of fishkill happened around the same time last year. He was cleaning the dead fish out of the canal and lagoon and was considering putting in aerators.”
Whatever was killing the fish, it didn’t seem to help CEATECH’s ammonia/nitrogen problem. CEATECH continued to exceed its effluent discharge levels through most of 2001, with ammonia nitrogen levels as high as 557.76 ug/L, and nitrogen as high as 3244.8 ug/L. It did, however, cause the neighboring Pacific Missile Range Facility to call the DOH and complain of “lots of dead fish in stream near the PMRF ‘Housing Gate’ causing odor,” according to an October 26, 2001 inspection report, which named CEATECH as the responsible party. A follow-up the next day by the DOH found no odor and no dead fish.
In response to claims that low dissolved oxygen is killing the tilapia, Sharon Ziegler-Chong of UH-Hilo Sea Grant says that tilapia don’t easily die from low dissolved oxygen because they can breathe air at the water’s surface. Longtime residents say that historically, after a rainfall, some dead fish turn up on the beach, but never in the large amounts seen since CEATECH’s arrival.
Steve Arnold, a fisherman who surfs Kekaha’s breaks, says, “In 25 years of living here, there are occasions where you see a few, not even a dozen dead tilapia on the beach. This year, it was over and over and over again. And that’s just the stuff on the beach. What else is floating out in the water?”
But is it all CEATECH’s fault? In an email to Environment Hawai`i, Paul Bienfang writes that CEATECH has only undertaken tilapia control efforts bi-annually, and primarily through netting and cage capture, “natural biological control via carnivores and rotenone applications. The latter is no longer used, and the former three have showed limited effectiveness.”
“We are now planning a re-engineering design of the discharge conduit that we feel will provide improved effectiveness over all previous practices,” Bienfang writes.
Whether or not the dead fish are the result of CEATECH’s actions, still others question company’s tilapia control efforts. For one thing, they say, it’s unlikely that tilapia can ever be controlled in an open canal system like Kekaha’s, where they can come and go as they please.
The DOH’s Mark Tomomitsu says. “Despite all their efforts, it’s been difficult. The tilapia bury themselves under sediment. … Once they get into ecosystem, it’s hard to get them out.”
Tomomitsu, an engineer, accepts CEATECH’s tilapia explanation. Others don’t.
Tilapia expert Kevin Hopkins of the University of Hawai`i at Hilo’s Sea Grant program says, “Tilapia cannot create nitrogen. They’re converting it. The ammonia comes from an external source … like the digestion of shrimp.” Even if there were no tilapia, he says, the algae in the system would convert the farm’s effluent into ammonia/nitrogen, anyway.
Even so, Bienfang points to the fish: “The fish populations are at a level that they undoubtedly contribute very significantly. Naturally, the farm effluent also contributes to the total. The farm’s portion reflects in part the effectiveness of the extensive sedimentation system for collection/retention of the settleable particulates. It is very effective at retaining particulate waste materials, and the subsequent microbial digestion of this material will contribute dissolved nitrogenous compounds. The company also has plans for an advanced in-line biological treatment system within the collection/conveyance infrastructure.”
While he disagrees with the tilapia theory, Hopkins is quick to point out that having a high level of ammonia or nitrogen at the discharge point is not automatically a danger to the marine environment. Under NPDES permits, levels of certain chemicals are measured at the discharge point and within a Zone of Mixing (ZOM), which is an area of open ocean area where high levels of those chemicals are allowed. In CEATECH’s case, it has rarely had violations in the ZOM. “If the Zone of Mixing is fine, why look at the discharge point?” he asks.
Libre disagrees. “They are not in compliance and they’re planning expansion,” she says.
— Teresa Dawson
Volume 12 Number 12 June 2002
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