Table 4.

Average percent (AVG %) inhibition of bacterial production (0% naphthalene addition control) relative to 25 μg naphthalene addition for upriver stations (1–3), at the station 4 outfall, and downriver stations (5-A2)

Stations	Distance from station 4 permitted outfall (km)	Inhibition of production by 25 μg naphthalene addition (AVG %)	Total PAH concentration (range, μg g−1)
1	4.5	61	1.9–5.9
2	2	57	<DL–1.7
3	1	40	<DL
4	0	9	0.23–3.2
5	1	25	1.3–2.6
6A–6E	3	51	0.69–4.5
10–12	7	66	<DL–4.4
17	13	60	<DL
A1	15	59	<DL–0.25
A2	11	77	<DL–0.54

Range of total PAH concentration in the surface sediment (μg g⁻¹). Naphthalene concentration at all stations ranged from below the detection limit (< DL) of 0.01–0.04 μg g⁻¹