diff --git a/environment-dev.yml b/environment-dev.yml
index 7a47ed7..765f2f0 100644
--- a/environment-dev.yml
+++ b/environment-dev.yml
@@ -25,6 +25,7 @@ dependencies:
   - more-itertools==8.13.0
   - pydantic>2
   - echopype
+  - haversine
   - black
   - bottleneck
   - check-manifest
diff --git a/environment.yml b/environment.yml
index 7ab5975..72f3ae4 100644
--- a/environment.yml
+++ b/environment.yml
@@ -23,6 +23,7 @@ dependencies:
   - more-itertools==8.13.0
   - pydantic>2
   - echopype
+  - haversine
   - pip
   - git
   - pip:
diff --git a/oceanstream/L2_calibrated_data/sv_interpolation.py b/oceanstream/L2_calibrated_data/sv_interpolation.py
index 06e472b..2514573 100644
--- a/oceanstream/L2_calibrated_data/sv_interpolation.py
+++ b/oceanstream/L2_calibrated_data/sv_interpolation.py
@@ -54,7 +54,7 @@ def interpolate_sv(
         dataset = read_processed(path_to_file)
 
     # Retrieve the Sv DataArray from the dataset
-    sv_dataarray = dataset["Sv"]
+    sv_dataarray = dataset["Sv"].chunk({"ping_time": -1})
 
     # Initialize an empty list to store the processed channels
     processed_channels = []
diff --git a/tests/test_nasc_process.py b/tests/test_nasc_process.py
index 2a09c10..4e674c4 100644
--- a/tests/test_nasc_process.py
+++ b/tests/test_nasc_process.py
@@ -16,11 +16,11 @@ def test_compute_per_dataset_nasc(ek_60_Sv_full_denoised):
 def test_compute_masked_nasc(ek_60_Sv_shoal):
     dataset = ek_60_Sv_shoal
     fish_nasc = mask_nasc_data(dataset, {"mask_shoal": False}, True, "fish_NASC")
-    assert fish_nasc['fish_NASC_38000.0'] == 148692889.40505505
+    assert fish_nasc['fish_NASC_38000.0'] == pytest.approx(131203167, 0.0001)
 
 
 def test_compute_full_nasc(ek_60_Sv_shoal):
     dataset = ek_60_Sv_shoal
     nasc = full_nasc_data(dataset, BASE_NASC_PARAMETERS)
     assert len(nasc) == 24
-    assert nasc['fish_NASC_38000.0'] == 148692889.40505505
+    assert nasc['fish_NASC_38000.0'] == pytest.approx(131203167, 0.0001)